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Mitral valve replacement versus reconstruction
Mitral valve replacement versus reconstruction An analysis of indications and results of mitral valve procedures in a consecutive series of 80 patients Case histories of 80 patients undergoing mitral valve procedures over a 2 year period were analyzed to determine the preoperative and intraoperative factors favoring reconstruction. Of 34 patients undergoing valve reconstruction, 31 (90 per cent) were women, and the average age of patients undergoing reconstruction was 41 versus 51 for patients who underwent replacement. Absence of calcification on fluoroscopic study and at operation favored reconstruction, as did the finding of good leaflet mobility by preoperative echocardiograms and operative assessment. Pure lesions, i.e., stenosis or insufficiency, favored reconstruction. In this regard, the use of new annuloplasty techniques has facilitated the surgeon's ability to reconstruct regurgitant mitral valves. No operative deaths and excellent functional and clinical results obtained in 80 per cent of patients undergoing mitral reconstruction justify the aggressive application of this technique in properly selected patients.
James H. Oury, M.D.,* Kirk L. Peterson, M.D.,** Theodore L. Folkerth, Commander (MC) USN,*** and Pat O. Daily, M.D.,* San Diego, Calif.
1/ ollowing early pioneering efforts at open reconstruction of the mitral valve, 1-4 prosthetic replacement has been utilized as the primary treatment for mitral valve disease by cardiac surgeons in the United States.5' 7 Several reasons for this may be cited: (1) recent technical advances in prosthetic valves and their ready availability; (2) the greater ease of prosthetic replacement as compared to the more tedious and often less reliable functional results of mitral reconstruction together with the uncertain long-term durability of the repair procedure; (3) the fact that valve replacement often involves a decision made preoperatively on the basis of cardiac catheterization and angiographic data, and requires less intraoperative judgment. As a consequence of these reasons, a fourth may be mentioned, that is, the resultant failure of young surgeons to learn Read at the Second Annual Meeting of The Samson Thoracic Surgical Society, Banff, Alberta, Canada, June 1-4, 1976. Address for reprints: James H. Oury, M.D., 7930 Frost St., Suite 305, San Diego, Calif. 92123. *Division of Cardiac Surgery, University Hospital, University of California, San Diego, 225 West Dickinson Street, San Diego, Calif. 92103. **Division of Cardiology, University Hospital, University of California, San Diego. ***Department of Cardiothoracic Surgery, Naval Hospital, San Diego, Calif.
and acquire the techniques and skills of more experienced surgeons gifted in the art of reconstruction. Advocates of reconstructive procedures claim the advantage of preservation of a more physiological valve mechanism as well as a lower thromboembolic rate with freedom from anticoagulation in most cases. The conviction that prosthetic mitral valve replacement is associated with numerous and significant longterm complications served as the stimulus to review a consecutive series of 80 patients undergoing mitral valve procedures over a 2 year period from 1973 to 1975 at the Naval Hospital, San Diego, California. The feasibility and long-term efficacy of mitral reconstructive procedures in selected patients has been reported by others. 8-14 We wish to amplify those preoperative and intraoperative factors leading toward a reconstructive procedure. Patients The group analyzed consisted of 80 patients; 46 underwent mitral valve replacement, and 34 underwent mitral valve reconstruction. Fifteen patients (19 per cent) underwent a mitral valve procedure in conjunction with other valvular procedures, and 8 patients (10 per cent) had concomitant coronary artery bypass grafts (CABG). All operations were performed with cardiopulmo825
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8 2 6 Oury et al.
Table I. Spectrum of mitral valve surgery at the Naval Regional Medical Center San Diego, California, from 1973 to 1975
7pts. (20.5%)
Cases Preoperative diagnosis I. II. III. IV.
Simple Commissurotomy
No.
17 37 21 5
Rheumatic mitral stenosis Rheumatic mitral stenosis and insufficiency Pure mitral insufficiency Prosthetic valve failure
22 46 26 6
,
nut —
80
7
.
*
*
'
-
.
■
'
-
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8ubvafvutef '"
Table II. Preoperative profile of patients undergoing mitral valve replacement and reconstruction (77 patients, 80 procedures) Mitral replacement (N = 46)
Mitral reconstruction (N = 34)
Preoperative profile Age (average and range) Sex(M:F) N.Y.H.A. Class III-IV Previous mitral procedures Presence of calcification
51 (32-67) 16:30 32 (70%) 17 (37%) 22 (48%)
41 (21-66) 3:31 26 (76%) 7 (20%) 6(16%)
Preoperative diagnosis I. Pure stenosis II. Mixed lesions III. Pure regurgitation IV. Replace prosthesis
3 21 17 5
14 (40%) 16 (50%) 4(10%) 0
Totals
46
(6.5%) (45.5%) (37%) (10%)
34
nary bypass (CPB) by use of moderate hypothermia (30 to 32° C ) , aortic cross-clamping, and myocardial surface cooling for myocardial protection.15 Patients were routinely given Warfarin for 6 weeks postoperatively. Anticoagulation was then discontinued unless there remained a strong indication to continue anticoagulation, such as a history of thromboembolism, giant left atrium, or unstable atrial fibrillation. Table I presents the preoperative diagnosis in these 80 patients with mitral valve disease. Seventeen patients (22 per cent) had pure mitral stenosis, 37 patients (46 per cent) had mixed rheumatic stenosis and insufficiency, and 21 patients (26 per cent) had pure mitral insufficiency; 5 patients (6 per cent) had replacement of previous mitral prostheses. The preoperative profile is given in Table II. The average age of patients undergoing replacement was 51 years as compared to an average age of 41 years in patients having mitral reconstruction. The over-all ratio
Fig. 1. Summary of operative procedures performed on patients undergoing open mitral reconstruction.
of men to women was 19:61, with the most marked preponderance of women in the reconstructive series 3:31 (90 per cent). New York Heart Association (N.Y.H.A.) classification preoperatively was similar in the two groups, with the majority of patients (70 and 76 per cent, respectively) in Classes III and IV. Calcification was present according to fluoroscopic studies in 48 per cent of the patients having mitral valve replacement and 16 per cent of patients who subsequently underwent mitral reconstruction. In 1974, midway in the series, the technique of annuloplasty employing the Carpentier ring was initiated. This technique provided a method of remodeling the mitral annulus on a frame to provide a more predictable annuloplasty.16 Results Table II provides a breakdown of the diagnostic categories and procedures performed in this series of patients. Forty-six patients underwent valve replacement, 7 with Beall valves followed by 39 patients with porcine heterografts. There were six deaths in the mitral valve replacement series (13 per cent). Thirty-four patients underwent valvular reconstruction, 7 with the Carpentier ring. There were no deaths in this series. Significant calcification was found in 22 of 41 patients (54 per cent) undergoing mitral valve replacement (5 patients or 10 per cent undergoing replacement of a previous prosthesis were excluded from this calculation), and in only 6 of 34 patients undergoing mitral reconstruction (16 per cent). The actual operative pro-
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Mitral valve replacement versus reconstruction
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Fig. 2. Preoperative (A) and postoperative (B) systolic left ventricular cineangiograms in a patient with severe mitral insufficiency secondary to ruptured posterior leaflet chordae. Note the competent valve mechanism seen postoperatively (B). cedure employed in the patients having valvular reconstruction is shown in Fig. 1. Simple commissurotomy without extensive subvalvular reconstruction was performed in 7 patients (20.5 per cent) with pure valvular stenosis. Commissurotomy plus subvalvular reconstruction was used in 20 patients (59 per cent) and consisted of splitting or tailoring of chordae and papillary muscle, resection of secondary chordae, and debridement of the valve. Ring annuloplasty was utilized to restore competence in 7 patients (20.5 per cent) undergoing mitral reconstruction. Postoperative hemodynamic studies were obtained in all patients undergoing mitral reconstruction with the Carpentier ring and have been presented elsewhere.17 One example of a patient in this category is shown in Fig. 2, A andfi. Fig. 2, A demonstrates free regurgitation in this patient with ruptured chordae to the posterior leaflet. Following resection of the midportion of the posterior leaflet and annuloplasty with the Carpentier ring, the postoperative angiogram (Fig. 2, B) demonstrates a competent mitral mechanism with no regurgitation. No transvalvular gradient was noted at the time of postoperative catheterization. The resected portion of the posterior leaflet is shown in Fig. 3 and illustrates the fact that as much as one half of the posterior leaflet may be resected without compromising the functional result. Fig. 4 summarizes the anatomic and functional results in patients undergoing mitral reconstruction. There were no operative deaths, and follow-up was 100 per cent in this group of patients with a mean interval of
Fig. 3. Resected portion of the posterior leaflet with ruptured chordae. 30 months. No residual murmur could be detected in 12 patients (35 per cent), and in an additional 51 (44 per cent) a Grade 1-2/6 murmur not regarded as hemodynamically significant was noted. This group represents the patients considered to be in N.Y.H.A. Class I at an average follow-up interval of 18 months. Four patients were found to have a Grade 3/6 murmur and, although clinically improved, were classified in N.Y.H.A. Class II from a functional standpoint. In 3 patients, valvular reconstruction was considered to have failured during
The Journal of Thoracic and Cardiovascular Surgery
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FUNCTIONAL CLASSIFICATION
referred
ANATOMIC RESULTS
for valve" replacement
subsequent valve . replacement . # « ! „
IjnB
Qr CRnlcally Improved
kSpto.
No MR Murniw 18 pit. (95%)
Qr I - II MR Murmur 15pts. (44%) operative mortality t o
Fig. 4. Summary of the functional and anatomic results in 34 patients undergoing mitral reconstruction. MR, Mitral regurgitation. RECONSTRUCTION
REPLACEMENT
preop
Fig. 5. Summary of functional result (according to N.Y.H.A. classes) in patients undergoing mitral valve replacement and reconstruction at a mean follow-up interval of 30 months. the first 18 months of follow-up, and all 3 have subsequently undergone valve replacement. The comparison between the functional results in patients having valve reconstruction and replacement is shown in Fig. 5. As expected in a younger age group and in patients with a less-advanced form of the disease, the majority of patients undergoing valve reconstruction progressed to Class I (80 per cent). By comparison, 66 per cent of patients undergoing mitral valve replacement progressed to Class I. Subsequent follow-up to a mean of 30 months has revealed one late death in the mitral replacement series owing to chronic obstructive pulmo-
nary disease, and no deaths in the mitral reconstruction series. There has been gradual deterioration in the clinical status of some patients in the over-all series, with 6 additional patients going from Class I to Class II in the mitral reconstruction series and 3 patients going from Class I to Class II in the valve replacement series. Operative techniques Several techniques are helpful in the intraoperative assessment of the mitral valve and the subsequent procedure employed. In all patients, a median sternotomy was used, the incision of choice in view of the fre-
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Fig. 6. Postoperative systolic angiogram in patient with mitral insufficiency owing to coronary artery disease following surgical repair of annular dilatation and coronary artery bypass graft. quency with which associated procedures are employed. Operative exposure of the mitral valve and subvalvular mechanism is facilitated by total cardiac relaxation acheived with ischemic arrest. For this purpose aortic cross-clamping is used with systemic hypothermia to 30° C. and myocardial surface cooling for myocardial protection.15 Blanko retractors* inserted through the mitral orifice to retract the anterior and posterior leaflets independently allow excellent exposure of the valve leaflets and subvalvular mechanism. Commissurotomy if needed is then performed, and the mobility of the anterior leaflet and state of the subvalvular mechanism are evaluated. If with gentle retraction the anterior leaflet prolapses beyond the plane of the mitral annulus, valve replacement is performed. Similarly, if the architecture of the subvalvular mechanisms is destroyed with papillary muscles in close proximity to the valve tissues, no attempt is made to reconstruct the valve. Fused chordae may be split and secondary chordae and subvalvular scarring resected. Localized deposits of calcium in the leaflet that is otherwise pliable may also be debrided and the valve preserved. Many surgical techniques to correct acquired nonrheumatic mitral regurgitation have been described, and the clinical management and summary of these procedures has been detailed by Kremkau and associates.18 Excision or plication of the involved leaflet tissue, usually with annuloplasty, has been advocated by McGoon19 with later modifications by Gerbode20 and *Pilling Company, Fort Washington, Pa.
others. Our approach to ruptured chordae supplying the posterior leaflet has been a wedge resection of that portion of the leaflet supplied by the involved chordae with the excision extending in a triangular fashion with the apex at the annulus. The cut edges of the leaflet are then approximated with fine interrupted sutures, and an appropriately sized Carpentier ring is selected and inserted. This technique has been previously described by Carpentier and associates.16 Involvement of both leaflets by chordal rupture serves as an indication for valve replacement as suggested by Ellis.11 Ruptured papillary muscle with resultant massive regurgitation falls into this category by virtue of the contribution of both papillary muscles to both anterior and posterior leaflets. Mitral regurgitation secondary to annular dilatation may also be managed effectively by a reconstructive procedure. In this case, the primary pathological process is usually related to coronary artery disease and must be treated concomitantly by CABG and/or aneurysm resection if indicated. Fig. 6 illustrates the postoperative systolic angiogram in a 46-year-old man with coronary artery disease and 4+ mitral regurgitation secondary to annular dilatation. He underwent a mitral annuloplasty with the Carpentier ring and CABG to the left anterior descending branch of the left coronary artery. No gradient was demonstrated postoperatively at catheterization, and the patient is currently in functional Class I. The competence of the valvular reconstruction may be tested with the aorta undamped either by rendering the aortic valve incompetent with gentle digital
8 3 0 Oury et al.
pressure to the transverse sinus or by injecting saline through the valve with a bulb syringe or through a venting catheter placed in the apex of the left ventricle. Failure of the anterior and posterior leaflets to coapt signifies an inadequate repair or noncompliant valve leaflets. Valve replacement should then be carried out. Mitral competence may also be evaluated by digital examination following discontinuance of CPB. The presence of a significant regurgitant jet through the mitral valve or a significant early regurgitant V wave with pressure monitoring should prompt consideration of valve replacement. Measurement of a transvalvular gradient of greater than 6 mm. Hg at the close of the reconstructive procedure (assuming a relatively normal cardiac output, as measured by thermodilution with a Swan-Ganz catheter, and assuming a heart rate of less than 110 beats per minute) indicates inadequate reconstruction, usually owing to persistence of subvalvular obstruction. It should be recognized in this regard that absolute quantitation of intraoperative mitral insufficiency by these pressure-pulse determinations is significantly altered by multiple factors. Left atrial compliance, cardiac output, heart rate, the contractile state of the left ventricle, and peripheral resistance all may alter the assessment of absolute values determined intraoperatively. Therefore, these determinations must be interpreted and the decision made regarding the adequacy of reconstruction in the light of the desired goal of operation, the patient's age, and associated cardiac disease. The routine use of a 16 gauge cathether placed through the right superior pulmonary vein into the left atrium at the time of closure of the left atrial incision facilitates the assessment of the operative procedure as well as aiding in the postoperative management. The additional operating time necessary for insertion of this catheter is negligible, the data supplied highly reliable for periods of up to 96 hours postoperatively, and the subsequent removal safe and atraumatic.21 Discussion The controversy of replacement versus reconstruction in selected patients with mitral valve disease has existed for many years, with series demonstrating the relative merits of both procedures.12, 13, 16' 22-25 Prostheses currently available have the disadvantage of uncertain long-term durability, a variable incidence of hemolysis, subacute bacterial endocarditis, residual gradients, and perivalvular leakage. 26-29 Mitral reconstruction must remain the preferred method of treatment when a competent mitral mechanism can be obtained without significant transvalvular gradient. That
The Journal of Thoracic and Cardiovascular Surgery
this goal can be achieved in properly selected patients regardless of age has been documented by numerous short-term and long-term follow-up studies. 30-35 The increasing safety of CPB has contributed to the trend toward open procedures on the mitral valve versus closed procedures.36, 37 The presence of significant degrees of mitral regurgitation precludes closed procedures.38 Many operations to correct mitral regurgitation have been described. 1-4 ' 16, 39 Procedures in which the atrioventricular ring is narrowed by externally placed circumferential sutures are of historical interest only.40 Lillehei1 is credited with the first attempt at correcting mitral insufficiency by narrowing the annulus under direct vision. The annuloplasty technique that has been most universally adopted is the posterior medial annuloplasty of Merendino,2 later modified by Kay,4 Wooler,41 and Reed39 with satisfactory clinical and hemodynamic results. McGoon's19 technique of posterior leaflet plication and the subsequent modification of this technique by Gerbode20 have proved effective in cases of rupture of chordae of the posterior leaflet.19' 20 Carpentier's contribution of valvular remodeling on a frame has provided several significant advantages. First, it allows selected tailoring of the annulus at any point in its circumference. Second, it distributes the stress points of the standard annuloplasty techniques over the entire annulus. Third, the forward positioning of the anterior or aortic leaflet of the mitral valve toward the mural or posterior leaflet allows extensive resection of posterior leaflet tissue without loss of competence. The inflexibility of the ring and the thin Dacron sewing surface present a potential problem of increasing tension on the mitral leaflet tissue leading to disinsertion or tearing of the valve mechanism. This is currently being evaluated, and a modification of the ring's construction is anticipated.42 In addition to Carpentier's extensive experience with mitral valve reconstruction, Duran24 has reported a series of 84 patients in whom the Carpentier ring was utilized to reconstruct one or more valves, with excellent results reported in 73 per cent and good results in 20 per cent of patients on follow-up. A variation of this approach recently developed by Duran involves a totally flexible ring, and excellent early results are reported by the author.43 The question of late deterioration of reconstructive procedures has been raised by advocates of prosthetic valve replacement.23, 25 Actuarial survival curves of 100 patients undergoing isolated valve reconstruction as reported by Messmer,13 however, compare favorably with those of patients undergoing mitral valve replacement. The application of reconstructive techniques in the pediatric age group is of special concern,
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Mitral valve replacement versus reconstruction
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Fig. 7. Preoperative (left) and postoperative (right) echocardiograms in a patient with mixed rheumatic stenosis and insufficiency. Note the thick preoperative anterior and posterior leaflet (AL and PL) echos. Following reconstruction, the increased mobility of the mitral leaflets is evident, R, Echo from Carpentier ring used for annuloplasty. (Actual measurement of anterior leaflet e to f slope changed from 14 to 60 mm. per second following reconstruction.) for it is in this category of patients by virtue of their activity and longevity that would enjoy the greatest benefit from a reconstructive procedure. Gotsman and associates,44 after performing involving mitral valve operations in 182 children, advocate mitral valve replacement in children who have mitral insufficiency, mixed mitral stenosis and insufficiency, and calcific mitral stenosis because of disappointing long-term results with annuloplasty. Other series, notably those of Reed33 and Stevenson,34 however, strongly endorse the reconstructive procedures because of long-term follow-up. We favor the latter approach whenever possible. The critical question then becomes one of selecting the proper patient for valve reconstruction. This selection may be divided into two categories: (1) preoperative factors favoring reconstruction and (2) operative factors favoring reconstruction (Table III). In the young female patient with a mitral valve lesion in the absence of extensive calcification, reconstruction is favored. In predominantly pure lesions, i.e., mitral stenosis or insufficiency, reconstruction is again favored, although the presence of a mixed lesion in no
way rules out the possibility of reconstruction preoperatively. Preoperative calcification is a relative contraindication to reconstruction although again does not rule out the possibility. Echocardiography has helped to clarify the preoperative potential for reconstruction in patients with mitral valve disease.45 Calcification of mitral leaflets can be semi-quantitated by analyzing the presence or absence of multiple, thick, conglomerate echoes arising from the anterior mitral leaflet. In the presence of signs of heavy calcification and poor anterior cusp mobility, prosthetic mitral valve replacement is almost invariably necessary. By contrast, thin, single or double echoes from the mitral leaflets coupled with a wide opening excursion of the anterior leaflet during early diastole serve to predict the feasibility of a reconstructive procedure (Fig. 7). These parameters will also document a satisfactory reconstructive result as shown in the postoperative tracing. Cineangiographic imaging of the mitral valve leaflets and subvalvular apparatus on the lateral view of the left ventriculogram also helps to predict the potential for valve reconstruction. Visualization of shortening and
8 32
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Oury et al.
Table III. Indications for mitral valve
reconstruction
Preoperative factors favoring reconstruction 1. Young female patient 2. Absence of calcium on fluoroscopy 3. Echocardiographic evidence of normal or slightly diminished mobility of valve 4. Predominantly "pure" lesions (stenosis or insufficiency)
2
Operative assessment favoring reconstruction 1. Absence of extensive calcification 2. Absence of extensive subvalvular disease 3. Absence of significant anterior leaflet prolapse 4. Mobility of anterior leaflet
3
thickening of the chordae tendineae to the posterior leaflet on this view in patients with mitral stenosis portends difficulty in performing an adequate commissurotomy. Operative assessment favoring reconstruction is chiefly aimed at determining the compliance of the anterior leaflet, establishing the fact that significant anterior leaflet prolapse does not exist, and evaluating the extent of disease in the subvalvular mechanism. These indications are summarized in Table III. Patients with mixed rheumatic stenosis and insufficiency provide the greatest test of the surgeon's intraoperative judgment. After valvular reconstruction, failure of the anterior leaflet to "float" into good apposition with the posterior leaflet while the heart is in a relaxed state is an indication of a significantly altered valvular compliance. The presence of central regurgitation with prolapse of the anterior leaflet also indicates the need to proceed with valvular replacement. Contraindications for reconstruction include the presence of heavy calcification of the valve, far-advanced noncalcific subvalvular disease, and major chordal or papillary rupture involving the anterior or both leaflets. Acute bacterial endocarditis also precludes reconstruction.
4
5 6
7
8
9
Annuloplasty Under Direct Vision, Lancet 77: 446, 1957. Merendino, K. A., and Bruce, R. A.: One Hundred Seventeen Surgically Treated Cases of Valvular Rheumatic Heart Disease: With a Preliminary Report of Two Cases of Mitral Regurgitation Treated Under Direct Vision With the Aid of a Pump-Oxygenator, J. A. M. A. 164: 749, 1957. Gerbode, F., Keith, W. J., Osborn, J. J., and Selzer, A.: Correction of Mitral Insufficiency by Open Operation, Ann. Surg. 155: 846, 1961. Kay, E. B., Noguer, A. C , and Zimmerman, M. A.: Correction of Mitral Insufficiency Under Direct Vision, Circulation 21: 568, 1960. Effler, D. B., Favaloro, R., and Groves, L. K.: Heart Valve Replacement: Clinical Experience, Ann. Thorac. Surg. 1: 4, 1965. Roberts, W. C , Braunwald, E., and Morrow, A. G.: Acute Severe Mitral Regurgitation Secondary to Ruptured Chordae Tendineae, Circulation 33: 58, 1966. Sanders, C. A., Austen, W. G., Harthorne, J. W., Dinsmore, R. E., and Scannell, J. G.: Diagnosis and Surgical Treatment of Mitral Regurgitation Secondary to Ruptured Chordae Tendineae, N. Engl. J. Med 276: 943, 1967. Rumel, W. R., Vaughn, C. C , and Guibone, R. A.: Surgical Reconstruction of the Mitral Valve, Ann. Thorac. Surg. 8: 289, 1969. Kerth, W. J., Sharma, G., Hill, J. D., and Gerbode, F.: Comparison of the Late Results of Replacement and of Reconstructive Procedures for Acquired Mitral Valve Disease, J. THORAC. CARDIOVASC. SURG. 61: 14, 1971.
10 Belcher, J. R.: Conservative Approach to the Treatment of Mixed Mitral Valve Disease, Thorax 28: 608, 1973. 11 Ellis, F. H., Jr.: Open Reconstruction of the Mitral Valve, Surg. Clin. North Am. 53: 339, 1973. 12 Mullin, M. J., Engelman, R. M., Isom, O. W., Boyd, A. D., Glassman, E., and Spencer, F. C : Experience With Open Mitral Commissurotomy in 100 Consecutive Patients, Surgery 75: 974, 1974. 13 Messmer, B. J., Gattiker, K., Rothlin, M., and Senning, A.: Reconstruction of the Mitral Valve, Ann . Thorac. Surg. 16: 30, 1973. 14 Manhas, D. R., Rittenhouse, E. A., Hessel, E. A., II, and Merendino, K. A.: Reconstructive Surgery for the Treatment of Mitral Incompetence: Early and Late Re-
In the absence of these contraindications, an aggressive attitude toward reconstruction is warranted in patients with mitral valve disease regardless of the cause. Preservation of the patient's own valve tissue, resulting in more physiological mechanical function, and freedom from anticoagulation also favor reconstruction. Avoidance of the uncertainty regarding the long-term fate of currently available prosthetic and tissue valves as well as the complications relating to these prostheses also serves to recommend the technique of mitral reconstruction.
781, 1971. 15 Shumway, N. E., Lower, R. R., and Stofer, R. C : Selective Hypothermia of the Heart in Anoxic Cardiac Arrest, Surg. Gynecol. Obstet. 109: 750, 1959. 16 Carpentier, A., Deloche, A., Dauptain, J., Soyer, R., Blondeau, P., Piwnica, A., and Dubost, C : A New Reconstructive Operation for Correction of Mitral and
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61: 1, 1971. 17 Oury, J. H., Angell, W. W., Folkerth, T. L., and Fosburg, R. G.: Mitral Valve Reconstruction: Hemodynamic
sults in 91 Patients, J. THORAC. CARDIOVASC. SURG. 62:
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Evaluation of the Carpentier Ring, Chest. Submitted for publication. 18 Kremkau, E. L., Gilbertson, P. R., and Bristow, J. D.: Acquired Non Rheumatic Mitral Regurgitation: Clinical Management with Emphasis on Evaluation of Myocardial Performance, Progr. Cardiovasc. Dis. 15: 4, 1973. 19 McGoon, D. C : Repair of Mitral Insufficiency Due to Ruptured Chordae Tendineae, J. THORAC. CARDIOVASC. SURG. 39: 357,
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20 Gerbode, F., Kerth, W. J., Kelly, J. D., and Selzer, A.: The Surgical Correction of Mitral Insufficiency Due to Ruptured Chordae Tendineae, Bull. Soc. Int. Chir. 25: 483, 1966. 21 Humphrey, C. B., Oury, J. H., Virgilio, R. W., Gibbons, J. A., Folkerth, T. L., Shapiro, A. R., and Fosburg, R. G.: An Analysis of Direct and Indirect Measurements of Left Atrial Filling Pressure, J. THORAC. CARDIOVASC. SURG. 71: 643,
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22 Sanders, C. A., and Austen, W. G.: Mitral Regurgitation Secondary to Ruptured Chordae Tendineae, Heart Bull. 16: 61, 1967. 23 McGoon, D. C : Editorial: On Evaluating Valves, Mayo Clin. Proc. 49: 233, 1974. 24 Duran, C. M. G., Pomar, J. L., and Martinez, C : Changing Concepts in the Surgical Treatment of Acquired Valvular Heart Disease: Annuloplasties, J. Cardiovasc. Surg. (Torino) Special No. 1975. 25 Barnhorst, D. A., Oxman, H. A., Connolly, D. C , Pluth, J. R., Danielson, G. K., Wallace, R. B., and McGoon, D. C : Long-Term Follow-up of Isolated Replacement of the Aortic or Mitral Valve With the StarrEdwards Prosthesis, Am. J. Cardiol. 35: 228, 1975. 26 Kastor, J. A., Akbarian, M., Buckley, M. J., Dinsmore, R. E., Sander, C. A., Scannell, J. G., and Austen, W. G.: Paravalvular Leaks and Hemolytic Anemia Following Insertion of Starr-Edwards Aortic and Mitral Valves, J. THORAC. CARDIOVASC. SURG. 56: 270,
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27 Block, P. C , DeSanctis, R. W., Weingberg, A. N., and Austen, W. G.: Prosthetic Valve Endocarditis, J. THORAC. CARDIOVASC. SURG. 60: 540,
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28 Reis, R. L., Glancy, D. L., O'Brien, K., Epstein, S. E., and Morrow, A. G.: Clinical and Hemodynamic Assessment of Fabric-Covered Starr-Edwards Prosthetic Valves, J. THORAC. CARDIOVASC. SURG. 59: 84,
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29 Schottenfeld, M., Wisheart, J. D., Ross, J. K., Lincoln, J. C R., and Ross, D. N.: Cloth Destruction and Hemolysis With Totally Cloth-Covered Starr-Edwards Prostheses, Thorax 26: 159, 1971. 30 Reed, G. E.: Repair of Mitral Regurgitation, Am. J. Cardiol. 31: 494, 1973. 31 Selzer, A., Kelly, J. J., Kerth, W. J., and Gerbode, F.: Immediate and Long-Range Results of Valvuloplasty for Mitral Regurgitation Due to Ruptured Chordae Tendineae, Circulation 45, 46: 52, 1972 (Suppl. I). 32 Pakrashi, B. C , Mary, D. A., Elmufti, M. E., Wooler, G. H., and Ionescu, M. I.: Clinical and Haemodynamic Results of Mitral Annuloplasty, Br. Heart J. 36: 768, 1974.
833
33 Reed, G. E., Kloth, H. H., Kiely, B., Danilowicz, D. A., Rader, B., and Doyle, E. F.: Long-Term Results of Mitral Annuloplasty in Children With Rheumatic Mitral Regurgitation, Circulation 49, 50: 189, 1974 (Suppl. II). 34 Stevenson, Kawabori, I., Morgan, B. C , Dillard, D. H., and Merendino, K. A.: Rheumatic Mitral Regurgitation: The Case for Annuloplasty in the Pediatric Age Group, Circulation 51, 52: 49, 1975 (Suppl. I). 35 Ross, B. A., Fox, C , Brown, H., Webb-Peploe, M., and Braimbridge, M. V.: Late Results of Valvuloplasty for Mitral Regurgitation Due to Rupture of Chordae of the Posterior (Mural) Cusp, J. THORAC. CARDIOVASC. SURG.
71: 4, 1976. 36 Finnegan, J. O., Gray, D. C , MacVaugh, H., HI, Joyner, C. R., and Johnson, J.: The Open Approach to Mitral Commissurotomy, SURG. 67: 75,
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37 Mullin, E. M., Glancy, D. L., Higgs, L. M., Epstein, S. E., and Morrow, A. G.: Current Results of Operation for Mitral Stenosis: Clinical and Hemodynamic Assessments in 124 Consecutive Patients Treated by Closed Commissurotomy, Open Commissurotomy, or Valve Replacement, Circulation 46: 298, 1972. 38 Grantham, R. N., Daggett, W. M., Cosimi, A. B., Buckley, M. J., Mundth, E. D., McEnany, M. T., Scannell, J. G., and Austen, W. G.: Transventricular Mitral Valvulotomy: Analysis of Factors Influencing Operative and Late Results, Circulation 49,50:200,1974 (Suppl. I). 39 Reed, G. E., Tice, D. A., and Clauss, R. H.: Asymmetric Exaggerated Mitral Annuloplasty: Repair of Mitral Insufficiency With Hemodynamic Predictability, J. THORAC. CARDIOVASC. SURG. 49: 752,
1965.
40 Davila, J. C , and Glover, R. L.: Circumferential Suture of the Mitral Ring, J. THORAC. SURG. 30: 531, 1955.
41 Wooler, G. H., Nixon, P. G. F., Grimshaw, V. A., and Watson, D. A.: Experience With the Repair of the Mitral Valve in Mitral Incompetence, Thorax 17: 49, 1962. 42 Carpentier, A.: Personal communication. 43 Duran, C. M. G.: Conservative Surgery: Experience With Mitral Annuloplasty, International Symposium on the Mitral Valve, Paris, France, May 26-28, 1975. 44 Gotsman, M. S., Van Der Horst, R. L., and Le Roux, B. T.: An Approach to the Surgery of Mitral Valve Disease in Children, Isr. Med. Sci. 2: 130, 1975. 45 Nanda, N. C , Gramiak, R., Shah, P. M., and DeWeese, J. A.: Mitral Commissurotomy Versus Replacement: Preoperative Evaluation by Echocardiography, Circulation 51: 263, 1975.
Discussion DR. DAVID
DILLARD
Seattle, Wash.
Our philosophy very closely parallels that of Dr. Oury. Dr. Merendino of our group was one of the first to do mitral annuloplasty. [Slide] We still prefer this technique wherever possible. We do not use a Carpentier ring, preferring a simple posteromedial annuloplasty when the tissues are of good quality.
8 34
The Journal of Thoracic and Cardiovascular Surgery
Oury et al.
The long-term results continue to be excellent, nearly 20 years later, and in our judgment exceed those of any other technique. We are committed to the concept of reconstruction whenever possible. However, as Dr. Oury has pointed out, it is not suitable for all patients. Whereas many surgeons who generally favor replacement are looking more at reconstruction, our group, which has always and still does prefer plastic procedures, has tended to do more replacements. We do not believe this is a reversal of polarity but perhaps an approach to a more reasonable midpoint. [Slide] In this regard, it was of interest to me to compare our data and those of Dr. Oury over the same 2 test years. We find that our experience very closely parallels his experience. These data vary a bit from his in that these cases are pure mitral surgery. Associated procedures such as coronary artery surgery or other valves are excluded, but the comparison should be valid. We, too, did approximately only moderately more replacements than reconstructions during this same period with virtually identical mortality rates in both categories. However, what was of greater interest to me was a comparison of these data with those from previous 5 years. There was a reduction in the mortality rate, but the significant feature was the shift in surgical philosophy from reconstruction to more frequent use of valve replacement. From 1968 to 1972, 70 per cent of our procedures were reconstructive. This figure declined to approximately 50 per cent in 1973 and 1974. Stated simply, those valves which readily lent themselves to reconstruction were so treated. Difficult and questionable cases were shifted to the replacement group. This meant a favorable mortality rate for the reconstruction group, with no deaths, but also an improved mortality rate in the replacement group. Valuable time was not wasted on attempting a difficult reconstruction and then shifting to replacement because the repair was unsatisfactory. Our current viewpoint, which appears to parallel that of Dr. Oury, is that a good reconstruction procedure (and I emphasize "good") is better than a good mitral valve replacement. We find that a good reconstruction can be done in most patients with pure mitral insufficiency, in many patients with mitral stenosis, but in only a few patients with mixed mitral stenosis and mitral regurgitation; the recurrence rate is high in the third group. [Slide] Good reconstruction becomes progressively unlikely in additive fashion when the following are present: Calcium on x-ray or fluoroscopic studies, mixed mitral stenosis and regurgitation, a previous operation, a connective tissue disorder, decreased valve mobility by echocardiographic and/or angiographic studies, and subvalvular stenosis. Dr. Oury has made a fine presentation and expressed a viewpoint which we endorse. I would like to ask Dr. Oury if they had any patients in whom he felt the problem was primarily a connective tissue disorder. If so, how did he recognize it, and how did he treat them?
DR. W I L L I A M W. ANGELL San Jose, Calif.
We started using the Carpentier ring about the same time that Dr. Oury did in San Diego, and I think our experiences have been parallel. I would like to ask Dr. Oury about one point which we have observed: There is a striking difference between the patients with anterior and posterior leaflet disease. [Slide] We found that with posterior leaflet prolapse, in which we could resect a significant portion of the leaflet and then bring the annulus together and support the annulus circumferentially with a ring, we could gain almost complete competence of the valve in virtually all cases. By contrast, we found that 50 per cent of the patients with disease of the anterior leaflets returned with very significant recurrent murmurs. Accordingly, the reoperation rate in this latter group is high. I would like to ask whether Dr. Oury has had a similar experience or not. DR. BENSON B. ROE San Francisco, Calif.
I rise as a proponent of mitral reconstruction to modify our former position and to add a word of caution. I agree that the opportunities for salvaging diseased mitral valves with the techniques which Dr. Oury has described deserve wider application. The thesis for reconstruction is most strongly supported by the fact that the potential orifice of a circular replacement device which fits in the kidneyshaped mitral annulus is necessarily much less than the normal cross-sectional area. Thus even a poor anatomic opening may exceed a prosthetic orifice. The pathway created by a finger or instrument forced through the valve orifice does not reflect the orifice provided by diastolic filling pressure. I urge Dr. Oury and others to classify their operative results according to whether the leaflets fall open in the relaxed state ( " A " result) or whether the semi-rigid leaflets have to be pushed open to provide the best potential orifice ( " B " result). We have been somewhat disappointed with the results of late function studies even in patients who had " A " result and hence have lost some of our enthusiasm for the reconstructive effort. Nevertheless, replacements are not without their problems, and Dr. Oury's methods are to be encouraged. D R . O U R Y (Closing) In regard to Dr. Dillard's comments, I must confess to a certain amount of trepidation in bringing a paper of this type before this Society. It perhaps is the surgical equivalent of carrying coals to Newcastle to discuss mitral reconstruction in the presence of many people who are the pioneers in this procedure. Certainly Dr. Dillard's group and the work of Dr. Merendino fall into this category. We have not used the asymmetric annuloplasty because we simply do not know how to do that procedure well. In that sense, perhaps the Carpentier ring is somewhat of a cop-out, but I regard it as an effective way of achieving a staged
Volume 73 Number 6 June, 1977
annuloplasty. At least with our short-term results and the longer term results of Dr. Carpentier, the ring seems to have value in terms of its lasting ability. Dr. Angell, we also have had a problem with assessing the anterior leaflet, and I think that is a key issue. Actually, we have solved this problem by assuming that any patient who has a significant amount of anterior leaflet prolapse or ruptured chordae involving the anterior leaflet is not amenable to reconstructive procedure. This opinion is at some variance with those advocates of reconstructive procedures, such as Dr. Carpentier, who feel that rather extensive anterior leaflet disease can be corrected. Frankly, I would like to wait to see the long-term results of these attempts at correction. In discussing anterior leaflet problems, Dr. Carpentier has said that they probably represent the poorer category of their
Mitral valve replacement versus reconstruction
835
reconstructive efforts, with a recurrence rate of about 20 per cent. Therefore, I think that goes along with what Dr. Angell has said regarding attempts to reconstruct the anterior leaflet of the mitral valve. I certainly appreciate Dr. Roe's comments, as he is one of the pioneers in this field. I think his idea about assessing in some sort of semi-quantitative fashion the mobility of the anterior leaflet is a good one. I would suggest that this be included in the form that he outlines or as a good description of the anterior leaflet mobility at the time of operation. Certainly, the patients in his " A " category are those who will have a very good reconstructive result. The " B " category comprises the patients who cause the biggest problems intraoperatively and require the most intraoperative judgment.
James H. Oury, M.D.,* Kirk L. Peterson, M.D.,** Theodore L. Folkerth, Commander (MC) USN,*** and Pat O. Daily, M.D.,* San Diego, Calif.
1/ ollowing early pioneering efforts at open reconstruction of the mitral valve, 1-4 prosthetic replacement has been utilized as the primary treatment for mitral valve disease by cardiac surgeons in the United States.5' 7 Several reasons for this may be cited: (1) recent technical advances in prosthetic valves and their ready availability; (2) the greater ease of prosthetic replacement as compared to the more tedious and often less reliable functional results of mitral reconstruction together with the uncertain long-term durability of the repair procedure; (3) the fact that valve replacement often involves a decision made preoperatively on the basis of cardiac catheterization and angiographic data, and requires less intraoperative judgment. As a consequence of these reasons, a fourth may be mentioned, that is, the resultant failure of young surgeons to learn Read at the Second Annual Meeting of The Samson Thoracic Surgical Society, Banff, Alberta, Canada, June 1-4, 1976. Address for reprints: James H. Oury, M.D., 7930 Frost St., Suite 305, San Diego, Calif. 92123. *Division of Cardiac Surgery, University Hospital, University of California, San Diego, 225 West Dickinson Street, San Diego, Calif. 92103. **Division of Cardiology, University Hospital, University of California, San Diego. ***Department of Cardiothoracic Surgery, Naval Hospital, San Diego, Calif.
and acquire the techniques and skills of more experienced surgeons gifted in the art of reconstruction. Advocates of reconstructive procedures claim the advantage of preservation of a more physiological valve mechanism as well as a lower thromboembolic rate with freedom from anticoagulation in most cases. The conviction that prosthetic mitral valve replacement is associated with numerous and significant longterm complications served as the stimulus to review a consecutive series of 80 patients undergoing mitral valve procedures over a 2 year period from 1973 to 1975 at the Naval Hospital, San Diego, California. The feasibility and long-term efficacy of mitral reconstructive procedures in selected patients has been reported by others. 8-14 We wish to amplify those preoperative and intraoperative factors leading toward a reconstructive procedure. Patients The group analyzed consisted of 80 patients; 46 underwent mitral valve replacement, and 34 underwent mitral valve reconstruction. Fifteen patients (19 per cent) underwent a mitral valve procedure in conjunction with other valvular procedures, and 8 patients (10 per cent) had concomitant coronary artery bypass grafts (CABG). All operations were performed with cardiopulmo825
The Journal of Thoracic and Cardiovascular Surgery
8 2 6 Oury et al.
Table I. Spectrum of mitral valve surgery at the Naval Regional Medical Center San Diego, California, from 1973 to 1975
7pts. (20.5%)
Cases Preoperative diagnosis I. II. III. IV.
Simple Commissurotomy
No.
17 37 21 5
Rheumatic mitral stenosis Rheumatic mitral stenosis and insufficiency Pure mitral insufficiency Prosthetic valve failure
22 46 26 6
,
nut —
80
7
.
*
*
'
-
.
■
'
-
\
'..:^rf*--!MM
8ubvafvutef '"
Table II. Preoperative profile of patients undergoing mitral valve replacement and reconstruction (77 patients, 80 procedures) Mitral replacement (N = 46)
Mitral reconstruction (N = 34)
Preoperative profile Age (average and range) Sex(M:F) N.Y.H.A. Class III-IV Previous mitral procedures Presence of calcification
51 (32-67) 16:30 32 (70%) 17 (37%) 22 (48%)
41 (21-66) 3:31 26 (76%) 7 (20%) 6(16%)
Preoperative diagnosis I. Pure stenosis II. Mixed lesions III. Pure regurgitation IV. Replace prosthesis
3 21 17 5
14 (40%) 16 (50%) 4(10%) 0
Totals
46
(6.5%) (45.5%) (37%) (10%)
34
nary bypass (CPB) by use of moderate hypothermia (30 to 32° C ) , aortic cross-clamping, and myocardial surface cooling for myocardial protection.15 Patients were routinely given Warfarin for 6 weeks postoperatively. Anticoagulation was then discontinued unless there remained a strong indication to continue anticoagulation, such as a history of thromboembolism, giant left atrium, or unstable atrial fibrillation. Table I presents the preoperative diagnosis in these 80 patients with mitral valve disease. Seventeen patients (22 per cent) had pure mitral stenosis, 37 patients (46 per cent) had mixed rheumatic stenosis and insufficiency, and 21 patients (26 per cent) had pure mitral insufficiency; 5 patients (6 per cent) had replacement of previous mitral prostheses. The preoperative profile is given in Table II. The average age of patients undergoing replacement was 51 years as compared to an average age of 41 years in patients having mitral reconstruction. The over-all ratio
Fig. 1. Summary of operative procedures performed on patients undergoing open mitral reconstruction.
of men to women was 19:61, with the most marked preponderance of women in the reconstructive series 3:31 (90 per cent). New York Heart Association (N.Y.H.A.) classification preoperatively was similar in the two groups, with the majority of patients (70 and 76 per cent, respectively) in Classes III and IV. Calcification was present according to fluoroscopic studies in 48 per cent of the patients having mitral valve replacement and 16 per cent of patients who subsequently underwent mitral reconstruction. In 1974, midway in the series, the technique of annuloplasty employing the Carpentier ring was initiated. This technique provided a method of remodeling the mitral annulus on a frame to provide a more predictable annuloplasty.16 Results Table II provides a breakdown of the diagnostic categories and procedures performed in this series of patients. Forty-six patients underwent valve replacement, 7 with Beall valves followed by 39 patients with porcine heterografts. There were six deaths in the mitral valve replacement series (13 per cent). Thirty-four patients underwent valvular reconstruction, 7 with the Carpentier ring. There were no deaths in this series. Significant calcification was found in 22 of 41 patients (54 per cent) undergoing mitral valve replacement (5 patients or 10 per cent undergoing replacement of a previous prosthesis were excluded from this calculation), and in only 6 of 34 patients undergoing mitral reconstruction (16 per cent). The actual operative pro-
Volume 73 Number 6 June, 1977
Mitral valve replacement versus reconstruction
827
Fig. 2. Preoperative (A) and postoperative (B) systolic left ventricular cineangiograms in a patient with severe mitral insufficiency secondary to ruptured posterior leaflet chordae. Note the competent valve mechanism seen postoperatively (B). cedure employed in the patients having valvular reconstruction is shown in Fig. 1. Simple commissurotomy without extensive subvalvular reconstruction was performed in 7 patients (20.5 per cent) with pure valvular stenosis. Commissurotomy plus subvalvular reconstruction was used in 20 patients (59 per cent) and consisted of splitting or tailoring of chordae and papillary muscle, resection of secondary chordae, and debridement of the valve. Ring annuloplasty was utilized to restore competence in 7 patients (20.5 per cent) undergoing mitral reconstruction. Postoperative hemodynamic studies were obtained in all patients undergoing mitral reconstruction with the Carpentier ring and have been presented elsewhere.17 One example of a patient in this category is shown in Fig. 2, A andfi. Fig. 2, A demonstrates free regurgitation in this patient with ruptured chordae to the posterior leaflet. Following resection of the midportion of the posterior leaflet and annuloplasty with the Carpentier ring, the postoperative angiogram (Fig. 2, B) demonstrates a competent mitral mechanism with no regurgitation. No transvalvular gradient was noted at the time of postoperative catheterization. The resected portion of the posterior leaflet is shown in Fig. 3 and illustrates the fact that as much as one half of the posterior leaflet may be resected without compromising the functional result. Fig. 4 summarizes the anatomic and functional results in patients undergoing mitral reconstruction. There were no operative deaths, and follow-up was 100 per cent in this group of patients with a mean interval of
Fig. 3. Resected portion of the posterior leaflet with ruptured chordae. 30 months. No residual murmur could be detected in 12 patients (35 per cent), and in an additional 51 (44 per cent) a Grade 1-2/6 murmur not regarded as hemodynamically significant was noted. This group represents the patients considered to be in N.Y.H.A. Class I at an average follow-up interval of 18 months. Four patients were found to have a Grade 3/6 murmur and, although clinically improved, were classified in N.Y.H.A. Class II from a functional standpoint. In 3 patients, valvular reconstruction was considered to have failured during
The Journal of Thoracic and Cardiovascular Surgery
8 2 8 Oury et al.
FUNCTIONAL CLASSIFICATION
referred
ANATOMIC RESULTS
for valve" replacement
subsequent valve . replacement . # « ! „
IjnB
Qr CRnlcally Improved
kSpto.
No MR Murniw 18 pit. (95%)
Qr I - II MR Murmur 15pts. (44%) operative mortality t o
Fig. 4. Summary of the functional and anatomic results in 34 patients undergoing mitral reconstruction. MR, Mitral regurgitation. RECONSTRUCTION
REPLACEMENT
preop
Fig. 5. Summary of functional result (according to N.Y.H.A. classes) in patients undergoing mitral valve replacement and reconstruction at a mean follow-up interval of 30 months. the first 18 months of follow-up, and all 3 have subsequently undergone valve replacement. The comparison between the functional results in patients having valve reconstruction and replacement is shown in Fig. 5. As expected in a younger age group and in patients with a less-advanced form of the disease, the majority of patients undergoing valve reconstruction progressed to Class I (80 per cent). By comparison, 66 per cent of patients undergoing mitral valve replacement progressed to Class I. Subsequent follow-up to a mean of 30 months has revealed one late death in the mitral replacement series owing to chronic obstructive pulmo-
nary disease, and no deaths in the mitral reconstruction series. There has been gradual deterioration in the clinical status of some patients in the over-all series, with 6 additional patients going from Class I to Class II in the mitral reconstruction series and 3 patients going from Class I to Class II in the valve replacement series. Operative techniques Several techniques are helpful in the intraoperative assessment of the mitral valve and the subsequent procedure employed. In all patients, a median sternotomy was used, the incision of choice in view of the fre-
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Mitral valve replacement versus reconstruction
829
Fig. 6. Postoperative systolic angiogram in patient with mitral insufficiency owing to coronary artery disease following surgical repair of annular dilatation and coronary artery bypass graft. quency with which associated procedures are employed. Operative exposure of the mitral valve and subvalvular mechanism is facilitated by total cardiac relaxation acheived with ischemic arrest. For this purpose aortic cross-clamping is used with systemic hypothermia to 30° C. and myocardial surface cooling for myocardial protection.15 Blanko retractors* inserted through the mitral orifice to retract the anterior and posterior leaflets independently allow excellent exposure of the valve leaflets and subvalvular mechanism. Commissurotomy if needed is then performed, and the mobility of the anterior leaflet and state of the subvalvular mechanism are evaluated. If with gentle retraction the anterior leaflet prolapses beyond the plane of the mitral annulus, valve replacement is performed. Similarly, if the architecture of the subvalvular mechanisms is destroyed with papillary muscles in close proximity to the valve tissues, no attempt is made to reconstruct the valve. Fused chordae may be split and secondary chordae and subvalvular scarring resected. Localized deposits of calcium in the leaflet that is otherwise pliable may also be debrided and the valve preserved. Many surgical techniques to correct acquired nonrheumatic mitral regurgitation have been described, and the clinical management and summary of these procedures has been detailed by Kremkau and associates.18 Excision or plication of the involved leaflet tissue, usually with annuloplasty, has been advocated by McGoon19 with later modifications by Gerbode20 and *Pilling Company, Fort Washington, Pa.
others. Our approach to ruptured chordae supplying the posterior leaflet has been a wedge resection of that portion of the leaflet supplied by the involved chordae with the excision extending in a triangular fashion with the apex at the annulus. The cut edges of the leaflet are then approximated with fine interrupted sutures, and an appropriately sized Carpentier ring is selected and inserted. This technique has been previously described by Carpentier and associates.16 Involvement of both leaflets by chordal rupture serves as an indication for valve replacement as suggested by Ellis.11 Ruptured papillary muscle with resultant massive regurgitation falls into this category by virtue of the contribution of both papillary muscles to both anterior and posterior leaflets. Mitral regurgitation secondary to annular dilatation may also be managed effectively by a reconstructive procedure. In this case, the primary pathological process is usually related to coronary artery disease and must be treated concomitantly by CABG and/or aneurysm resection if indicated. Fig. 6 illustrates the postoperative systolic angiogram in a 46-year-old man with coronary artery disease and 4+ mitral regurgitation secondary to annular dilatation. He underwent a mitral annuloplasty with the Carpentier ring and CABG to the left anterior descending branch of the left coronary artery. No gradient was demonstrated postoperatively at catheterization, and the patient is currently in functional Class I. The competence of the valvular reconstruction may be tested with the aorta undamped either by rendering the aortic valve incompetent with gentle digital
8 3 0 Oury et al.
pressure to the transverse sinus or by injecting saline through the valve with a bulb syringe or through a venting catheter placed in the apex of the left ventricle. Failure of the anterior and posterior leaflets to coapt signifies an inadequate repair or noncompliant valve leaflets. Valve replacement should then be carried out. Mitral competence may also be evaluated by digital examination following discontinuance of CPB. The presence of a significant regurgitant jet through the mitral valve or a significant early regurgitant V wave with pressure monitoring should prompt consideration of valve replacement. Measurement of a transvalvular gradient of greater than 6 mm. Hg at the close of the reconstructive procedure (assuming a relatively normal cardiac output, as measured by thermodilution with a Swan-Ganz catheter, and assuming a heart rate of less than 110 beats per minute) indicates inadequate reconstruction, usually owing to persistence of subvalvular obstruction. It should be recognized in this regard that absolute quantitation of intraoperative mitral insufficiency by these pressure-pulse determinations is significantly altered by multiple factors. Left atrial compliance, cardiac output, heart rate, the contractile state of the left ventricle, and peripheral resistance all may alter the assessment of absolute values determined intraoperatively. Therefore, these determinations must be interpreted and the decision made regarding the adequacy of reconstruction in the light of the desired goal of operation, the patient's age, and associated cardiac disease. The routine use of a 16 gauge cathether placed through the right superior pulmonary vein into the left atrium at the time of closure of the left atrial incision facilitates the assessment of the operative procedure as well as aiding in the postoperative management. The additional operating time necessary for insertion of this catheter is negligible, the data supplied highly reliable for periods of up to 96 hours postoperatively, and the subsequent removal safe and atraumatic.21 Discussion The controversy of replacement versus reconstruction in selected patients with mitral valve disease has existed for many years, with series demonstrating the relative merits of both procedures.12, 13, 16' 22-25 Prostheses currently available have the disadvantage of uncertain long-term durability, a variable incidence of hemolysis, subacute bacterial endocarditis, residual gradients, and perivalvular leakage. 26-29 Mitral reconstruction must remain the preferred method of treatment when a competent mitral mechanism can be obtained without significant transvalvular gradient. That
The Journal of Thoracic and Cardiovascular Surgery
this goal can be achieved in properly selected patients regardless of age has been documented by numerous short-term and long-term follow-up studies. 30-35 The increasing safety of CPB has contributed to the trend toward open procedures on the mitral valve versus closed procedures.36, 37 The presence of significant degrees of mitral regurgitation precludes closed procedures.38 Many operations to correct mitral regurgitation have been described. 1-4 ' 16, 39 Procedures in which the atrioventricular ring is narrowed by externally placed circumferential sutures are of historical interest only.40 Lillehei1 is credited with the first attempt at correcting mitral insufficiency by narrowing the annulus under direct vision. The annuloplasty technique that has been most universally adopted is the posterior medial annuloplasty of Merendino,2 later modified by Kay,4 Wooler,41 and Reed39 with satisfactory clinical and hemodynamic results. McGoon's19 technique of posterior leaflet plication and the subsequent modification of this technique by Gerbode20 have proved effective in cases of rupture of chordae of the posterior leaflet.19' 20 Carpentier's contribution of valvular remodeling on a frame has provided several significant advantages. First, it allows selected tailoring of the annulus at any point in its circumference. Second, it distributes the stress points of the standard annuloplasty techniques over the entire annulus. Third, the forward positioning of the anterior or aortic leaflet of the mitral valve toward the mural or posterior leaflet allows extensive resection of posterior leaflet tissue without loss of competence. The inflexibility of the ring and the thin Dacron sewing surface present a potential problem of increasing tension on the mitral leaflet tissue leading to disinsertion or tearing of the valve mechanism. This is currently being evaluated, and a modification of the ring's construction is anticipated.42 In addition to Carpentier's extensive experience with mitral valve reconstruction, Duran24 has reported a series of 84 patients in whom the Carpentier ring was utilized to reconstruct one or more valves, with excellent results reported in 73 per cent and good results in 20 per cent of patients on follow-up. A variation of this approach recently developed by Duran involves a totally flexible ring, and excellent early results are reported by the author.43 The question of late deterioration of reconstructive procedures has been raised by advocates of prosthetic valve replacement.23, 25 Actuarial survival curves of 100 patients undergoing isolated valve reconstruction as reported by Messmer,13 however, compare favorably with those of patients undergoing mitral valve replacement. The application of reconstructive techniques in the pediatric age group is of special concern,
Volume 73 Number 6 June, 1977
Mitral valve replacement versus reconstruction
831
Fig. 7. Preoperative (left) and postoperative (right) echocardiograms in a patient with mixed rheumatic stenosis and insufficiency. Note the thick preoperative anterior and posterior leaflet (AL and PL) echos. Following reconstruction, the increased mobility of the mitral leaflets is evident, R, Echo from Carpentier ring used for annuloplasty. (Actual measurement of anterior leaflet e to f slope changed from 14 to 60 mm. per second following reconstruction.) for it is in this category of patients by virtue of their activity and longevity that would enjoy the greatest benefit from a reconstructive procedure. Gotsman and associates,44 after performing involving mitral valve operations in 182 children, advocate mitral valve replacement in children who have mitral insufficiency, mixed mitral stenosis and insufficiency, and calcific mitral stenosis because of disappointing long-term results with annuloplasty. Other series, notably those of Reed33 and Stevenson,34 however, strongly endorse the reconstructive procedures because of long-term follow-up. We favor the latter approach whenever possible. The critical question then becomes one of selecting the proper patient for valve reconstruction. This selection may be divided into two categories: (1) preoperative factors favoring reconstruction and (2) operative factors favoring reconstruction (Table III). In the young female patient with a mitral valve lesion in the absence of extensive calcification, reconstruction is favored. In predominantly pure lesions, i.e., mitral stenosis or insufficiency, reconstruction is again favored, although the presence of a mixed lesion in no
way rules out the possibility of reconstruction preoperatively. Preoperative calcification is a relative contraindication to reconstruction although again does not rule out the possibility. Echocardiography has helped to clarify the preoperative potential for reconstruction in patients with mitral valve disease.45 Calcification of mitral leaflets can be semi-quantitated by analyzing the presence or absence of multiple, thick, conglomerate echoes arising from the anterior mitral leaflet. In the presence of signs of heavy calcification and poor anterior cusp mobility, prosthetic mitral valve replacement is almost invariably necessary. By contrast, thin, single or double echoes from the mitral leaflets coupled with a wide opening excursion of the anterior leaflet during early diastole serve to predict the feasibility of a reconstructive procedure (Fig. 7). These parameters will also document a satisfactory reconstructive result as shown in the postoperative tracing. Cineangiographic imaging of the mitral valve leaflets and subvalvular apparatus on the lateral view of the left ventriculogram also helps to predict the potential for valve reconstruction. Visualization of shortening and
8 32
The Journal of Thoracic and Cardiovascular Surgery
Oury et al.
Table III. Indications for mitral valve
reconstruction
Preoperative factors favoring reconstruction 1. Young female patient 2. Absence of calcium on fluoroscopy 3. Echocardiographic evidence of normal or slightly diminished mobility of valve 4. Predominantly "pure" lesions (stenosis or insufficiency)
2
Operative assessment favoring reconstruction 1. Absence of extensive calcification 2. Absence of extensive subvalvular disease 3. Absence of significant anterior leaflet prolapse 4. Mobility of anterior leaflet
3
thickening of the chordae tendineae to the posterior leaflet on this view in patients with mitral stenosis portends difficulty in performing an adequate commissurotomy. Operative assessment favoring reconstruction is chiefly aimed at determining the compliance of the anterior leaflet, establishing the fact that significant anterior leaflet prolapse does not exist, and evaluating the extent of disease in the subvalvular mechanism. These indications are summarized in Table III. Patients with mixed rheumatic stenosis and insufficiency provide the greatest test of the surgeon's intraoperative judgment. After valvular reconstruction, failure of the anterior leaflet to "float" into good apposition with the posterior leaflet while the heart is in a relaxed state is an indication of a significantly altered valvular compliance. The presence of central regurgitation with prolapse of the anterior leaflet also indicates the need to proceed with valvular replacement. Contraindications for reconstruction include the presence of heavy calcification of the valve, far-advanced noncalcific subvalvular disease, and major chordal or papillary rupture involving the anterior or both leaflets. Acute bacterial endocarditis also precludes reconstruction.
4
5 6
7
8
9
Annuloplasty Under Direct Vision, Lancet 77: 446, 1957. Merendino, K. A., and Bruce, R. A.: One Hundred Seventeen Surgically Treated Cases of Valvular Rheumatic Heart Disease: With a Preliminary Report of Two Cases of Mitral Regurgitation Treated Under Direct Vision With the Aid of a Pump-Oxygenator, J. A. M. A. 164: 749, 1957. Gerbode, F., Keith, W. J., Osborn, J. J., and Selzer, A.: Correction of Mitral Insufficiency by Open Operation, Ann. Surg. 155: 846, 1961. Kay, E. B., Noguer, A. C , and Zimmerman, M. A.: Correction of Mitral Insufficiency Under Direct Vision, Circulation 21: 568, 1960. Effler, D. B., Favaloro, R., and Groves, L. K.: Heart Valve Replacement: Clinical Experience, Ann. Thorac. Surg. 1: 4, 1965. Roberts, W. C , Braunwald, E., and Morrow, A. G.: Acute Severe Mitral Regurgitation Secondary to Ruptured Chordae Tendineae, Circulation 33: 58, 1966. Sanders, C. A., Austen, W. G., Harthorne, J. W., Dinsmore, R. E., and Scannell, J. G.: Diagnosis and Surgical Treatment of Mitral Regurgitation Secondary to Ruptured Chordae Tendineae, N. Engl. J. Med 276: 943, 1967. Rumel, W. R., Vaughn, C. C , and Guibone, R. A.: Surgical Reconstruction of the Mitral Valve, Ann. Thorac. Surg. 8: 289, 1969. Kerth, W. J., Sharma, G., Hill, J. D., and Gerbode, F.: Comparison of the Late Results of Replacement and of Reconstructive Procedures for Acquired Mitral Valve Disease, J. THORAC. CARDIOVASC. SURG. 61: 14, 1971.
10 Belcher, J. R.: Conservative Approach to the Treatment of Mixed Mitral Valve Disease, Thorax 28: 608, 1973. 11 Ellis, F. H., Jr.: Open Reconstruction of the Mitral Valve, Surg. Clin. North Am. 53: 339, 1973. 12 Mullin, M. J., Engelman, R. M., Isom, O. W., Boyd, A. D., Glassman, E., and Spencer, F. C : Experience With Open Mitral Commissurotomy in 100 Consecutive Patients, Surgery 75: 974, 1974. 13 Messmer, B. J., Gattiker, K., Rothlin, M., and Senning, A.: Reconstruction of the Mitral Valve, Ann . Thorac. Surg. 16: 30, 1973. 14 Manhas, D. R., Rittenhouse, E. A., Hessel, E. A., II, and Merendino, K. A.: Reconstructive Surgery for the Treatment of Mitral Incompetence: Early and Late Re-
In the absence of these contraindications, an aggressive attitude toward reconstruction is warranted in patients with mitral valve disease regardless of the cause. Preservation of the patient's own valve tissue, resulting in more physiological mechanical function, and freedom from anticoagulation also favor reconstruction. Avoidance of the uncertainty regarding the long-term fate of currently available prosthetic and tissue valves as well as the complications relating to these prostheses also serves to recommend the technique of mitral reconstruction.
781, 1971. 15 Shumway, N. E., Lower, R. R., and Stofer, R. C : Selective Hypothermia of the Heart in Anoxic Cardiac Arrest, Surg. Gynecol. Obstet. 109: 750, 1959. 16 Carpentier, A., Deloche, A., Dauptain, J., Soyer, R., Blondeau, P., Piwnica, A., and Dubost, C : A New Reconstructive Operation for Correction of Mitral and
REFERENCES 1 Lillehei, C. W., Gott, V. L., DeWall, R. A., and Varco, R. L.: Surgical Correction of Pure Mitral Insufficiency by
61: 1, 1971. 17 Oury, J. H., Angell, W. W., Folkerth, T. L., and Fosburg, R. G.: Mitral Valve Reconstruction: Hemodynamic
sults in 91 Patients, J. THORAC. CARDIOVASC. SURG. 62:
Tricuspid Insufficiency, J. THORAC. CARDIOVASC. SURG.
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Mitral valve replacement versus reconstruction
Evaluation of the Carpentier Ring, Chest. Submitted for publication. 18 Kremkau, E. L., Gilbertson, P. R., and Bristow, J. D.: Acquired Non Rheumatic Mitral Regurgitation: Clinical Management with Emphasis on Evaluation of Myocardial Performance, Progr. Cardiovasc. Dis. 15: 4, 1973. 19 McGoon, D. C : Repair of Mitral Insufficiency Due to Ruptured Chordae Tendineae, J. THORAC. CARDIOVASC. SURG. 39: 357,
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20 Gerbode, F., Kerth, W. J., Kelly, J. D., and Selzer, A.: The Surgical Correction of Mitral Insufficiency Due to Ruptured Chordae Tendineae, Bull. Soc. Int. Chir. 25: 483, 1966. 21 Humphrey, C. B., Oury, J. H., Virgilio, R. W., Gibbons, J. A., Folkerth, T. L., Shapiro, A. R., and Fosburg, R. G.: An Analysis of Direct and Indirect Measurements of Left Atrial Filling Pressure, J. THORAC. CARDIOVASC. SURG. 71: 643,
1976.
22 Sanders, C. A., and Austen, W. G.: Mitral Regurgitation Secondary to Ruptured Chordae Tendineae, Heart Bull. 16: 61, 1967. 23 McGoon, D. C : Editorial: On Evaluating Valves, Mayo Clin. Proc. 49: 233, 1974. 24 Duran, C. M. G., Pomar, J. L., and Martinez, C : Changing Concepts in the Surgical Treatment of Acquired Valvular Heart Disease: Annuloplasties, J. Cardiovasc. Surg. (Torino) Special No. 1975. 25 Barnhorst, D. A., Oxman, H. A., Connolly, D. C , Pluth, J. R., Danielson, G. K., Wallace, R. B., and McGoon, D. C : Long-Term Follow-up of Isolated Replacement of the Aortic or Mitral Valve With the StarrEdwards Prosthesis, Am. J. Cardiol. 35: 228, 1975. 26 Kastor, J. A., Akbarian, M., Buckley, M. J., Dinsmore, R. E., Sander, C. A., Scannell, J. G., and Austen, W. G.: Paravalvular Leaks and Hemolytic Anemia Following Insertion of Starr-Edwards Aortic and Mitral Valves, J. THORAC. CARDIOVASC. SURG. 56: 270,
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27 Block, P. C , DeSanctis, R. W., Weingberg, A. N., and Austen, W. G.: Prosthetic Valve Endocarditis, J. THORAC. CARDIOVASC. SURG. 60: 540,
1970.
28 Reis, R. L., Glancy, D. L., O'Brien, K., Epstein, S. E., and Morrow, A. G.: Clinical and Hemodynamic Assessment of Fabric-Covered Starr-Edwards Prosthetic Valves, J. THORAC. CARDIOVASC. SURG. 59: 84,
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29 Schottenfeld, M., Wisheart, J. D., Ross, J. K., Lincoln, J. C R., and Ross, D. N.: Cloth Destruction and Hemolysis With Totally Cloth-Covered Starr-Edwards Prostheses, Thorax 26: 159, 1971. 30 Reed, G. E.: Repair of Mitral Regurgitation, Am. J. Cardiol. 31: 494, 1973. 31 Selzer, A., Kelly, J. J., Kerth, W. J., and Gerbode, F.: Immediate and Long-Range Results of Valvuloplasty for Mitral Regurgitation Due to Ruptured Chordae Tendineae, Circulation 45, 46: 52, 1972 (Suppl. I). 32 Pakrashi, B. C , Mary, D. A., Elmufti, M. E., Wooler, G. H., and Ionescu, M. I.: Clinical and Haemodynamic Results of Mitral Annuloplasty, Br. Heart J. 36: 768, 1974.
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33 Reed, G. E., Kloth, H. H., Kiely, B., Danilowicz, D. A., Rader, B., and Doyle, E. F.: Long-Term Results of Mitral Annuloplasty in Children With Rheumatic Mitral Regurgitation, Circulation 49, 50: 189, 1974 (Suppl. II). 34 Stevenson, Kawabori, I., Morgan, B. C , Dillard, D. H., and Merendino, K. A.: Rheumatic Mitral Regurgitation: The Case for Annuloplasty in the Pediatric Age Group, Circulation 51, 52: 49, 1975 (Suppl. I). 35 Ross, B. A., Fox, C , Brown, H., Webb-Peploe, M., and Braimbridge, M. V.: Late Results of Valvuloplasty for Mitral Regurgitation Due to Rupture of Chordae of the Posterior (Mural) Cusp, J. THORAC. CARDIOVASC. SURG.
71: 4, 1976. 36 Finnegan, J. O., Gray, D. C , MacVaugh, H., HI, Joyner, C. R., and Johnson, J.: The Open Approach to Mitral Commissurotomy, SURG. 67: 75,
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37 Mullin, E. M., Glancy, D. L., Higgs, L. M., Epstein, S. E., and Morrow, A. G.: Current Results of Operation for Mitral Stenosis: Clinical and Hemodynamic Assessments in 124 Consecutive Patients Treated by Closed Commissurotomy, Open Commissurotomy, or Valve Replacement, Circulation 46: 298, 1972. 38 Grantham, R. N., Daggett, W. M., Cosimi, A. B., Buckley, M. J., Mundth, E. D., McEnany, M. T., Scannell, J. G., and Austen, W. G.: Transventricular Mitral Valvulotomy: Analysis of Factors Influencing Operative and Late Results, Circulation 49,50:200,1974 (Suppl. I). 39 Reed, G. E., Tice, D. A., and Clauss, R. H.: Asymmetric Exaggerated Mitral Annuloplasty: Repair of Mitral Insufficiency With Hemodynamic Predictability, J. THORAC. CARDIOVASC. SURG. 49: 752,
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40 Davila, J. C , and Glover, R. L.: Circumferential Suture of the Mitral Ring, J. THORAC. SURG. 30: 531, 1955.
41 Wooler, G. H., Nixon, P. G. F., Grimshaw, V. A., and Watson, D. A.: Experience With the Repair of the Mitral Valve in Mitral Incompetence, Thorax 17: 49, 1962. 42 Carpentier, A.: Personal communication. 43 Duran, C. M. G.: Conservative Surgery: Experience With Mitral Annuloplasty, International Symposium on the Mitral Valve, Paris, France, May 26-28, 1975. 44 Gotsman, M. S., Van Der Horst, R. L., and Le Roux, B. T.: An Approach to the Surgery of Mitral Valve Disease in Children, Isr. Med. Sci. 2: 130, 1975. 45 Nanda, N. C , Gramiak, R., Shah, P. M., and DeWeese, J. A.: Mitral Commissurotomy Versus Replacement: Preoperative Evaluation by Echocardiography, Circulation 51: 263, 1975.
Discussion DR. DAVID
DILLARD
Seattle, Wash.
Our philosophy very closely parallels that of Dr. Oury. Dr. Merendino of our group was one of the first to do mitral annuloplasty. [Slide] We still prefer this technique wherever possible. We do not use a Carpentier ring, preferring a simple posteromedial annuloplasty when the tissues are of good quality.
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The Journal of Thoracic and Cardiovascular Surgery
Oury et al.
The long-term results continue to be excellent, nearly 20 years later, and in our judgment exceed those of any other technique. We are committed to the concept of reconstruction whenever possible. However, as Dr. Oury has pointed out, it is not suitable for all patients. Whereas many surgeons who generally favor replacement are looking more at reconstruction, our group, which has always and still does prefer plastic procedures, has tended to do more replacements. We do not believe this is a reversal of polarity but perhaps an approach to a more reasonable midpoint. [Slide] In this regard, it was of interest to me to compare our data and those of Dr. Oury over the same 2 test years. We find that our experience very closely parallels his experience. These data vary a bit from his in that these cases are pure mitral surgery. Associated procedures such as coronary artery surgery or other valves are excluded, but the comparison should be valid. We, too, did approximately only moderately more replacements than reconstructions during this same period with virtually identical mortality rates in both categories. However, what was of greater interest to me was a comparison of these data with those from previous 5 years. There was a reduction in the mortality rate, but the significant feature was the shift in surgical philosophy from reconstruction to more frequent use of valve replacement. From 1968 to 1972, 70 per cent of our procedures were reconstructive. This figure declined to approximately 50 per cent in 1973 and 1974. Stated simply, those valves which readily lent themselves to reconstruction were so treated. Difficult and questionable cases were shifted to the replacement group. This meant a favorable mortality rate for the reconstruction group, with no deaths, but also an improved mortality rate in the replacement group. Valuable time was not wasted on attempting a difficult reconstruction and then shifting to replacement because the repair was unsatisfactory. Our current viewpoint, which appears to parallel that of Dr. Oury, is that a good reconstruction procedure (and I emphasize "good") is better than a good mitral valve replacement. We find that a good reconstruction can be done in most patients with pure mitral insufficiency, in many patients with mitral stenosis, but in only a few patients with mixed mitral stenosis and mitral regurgitation; the recurrence rate is high in the third group. [Slide] Good reconstruction becomes progressively unlikely in additive fashion when the following are present: Calcium on x-ray or fluoroscopic studies, mixed mitral stenosis and regurgitation, a previous operation, a connective tissue disorder, decreased valve mobility by echocardiographic and/or angiographic studies, and subvalvular stenosis. Dr. Oury has made a fine presentation and expressed a viewpoint which we endorse. I would like to ask Dr. Oury if they had any patients in whom he felt the problem was primarily a connective tissue disorder. If so, how did he recognize it, and how did he treat them?
DR. W I L L I A M W. ANGELL San Jose, Calif.
We started using the Carpentier ring about the same time that Dr. Oury did in San Diego, and I think our experiences have been parallel. I would like to ask Dr. Oury about one point which we have observed: There is a striking difference between the patients with anterior and posterior leaflet disease. [Slide] We found that with posterior leaflet prolapse, in which we could resect a significant portion of the leaflet and then bring the annulus together and support the annulus circumferentially with a ring, we could gain almost complete competence of the valve in virtually all cases. By contrast, we found that 50 per cent of the patients with disease of the anterior leaflets returned with very significant recurrent murmurs. Accordingly, the reoperation rate in this latter group is high. I would like to ask whether Dr. Oury has had a similar experience or not. DR. BENSON B. ROE San Francisco, Calif.
I rise as a proponent of mitral reconstruction to modify our former position and to add a word of caution. I agree that the opportunities for salvaging diseased mitral valves with the techniques which Dr. Oury has described deserve wider application. The thesis for reconstruction is most strongly supported by the fact that the potential orifice of a circular replacement device which fits in the kidneyshaped mitral annulus is necessarily much less than the normal cross-sectional area. Thus even a poor anatomic opening may exceed a prosthetic orifice. The pathway created by a finger or instrument forced through the valve orifice does not reflect the orifice provided by diastolic filling pressure. I urge Dr. Oury and others to classify their operative results according to whether the leaflets fall open in the relaxed state ( " A " result) or whether the semi-rigid leaflets have to be pushed open to provide the best potential orifice ( " B " result). We have been somewhat disappointed with the results of late function studies even in patients who had " A " result and hence have lost some of our enthusiasm for the reconstructive effort. Nevertheless, replacements are not without their problems, and Dr. Oury's methods are to be encouraged. D R . O U R Y (Closing) In regard to Dr. Dillard's comments, I must confess to a certain amount of trepidation in bringing a paper of this type before this Society. It perhaps is the surgical equivalent of carrying coals to Newcastle to discuss mitral reconstruction in the presence of many people who are the pioneers in this procedure. Certainly Dr. Dillard's group and the work of Dr. Merendino fall into this category. We have not used the asymmetric annuloplasty because we simply do not know how to do that procedure well. In that sense, perhaps the Carpentier ring is somewhat of a cop-out, but I regard it as an effective way of achieving a staged
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annuloplasty. At least with our short-term results and the longer term results of Dr. Carpentier, the ring seems to have value in terms of its lasting ability. Dr. Angell, we also have had a problem with assessing the anterior leaflet, and I think that is a key issue. Actually, we have solved this problem by assuming that any patient who has a significant amount of anterior leaflet prolapse or ruptured chordae involving the anterior leaflet is not amenable to reconstructive procedure. This opinion is at some variance with those advocates of reconstructive procedures, such as Dr. Carpentier, who feel that rather extensive anterior leaflet disease can be corrected. Frankly, I would like to wait to see the long-term results of these attempts at correction. In discussing anterior leaflet problems, Dr. Carpentier has said that they probably represent the poorer category of their
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reconstructive efforts, with a recurrence rate of about 20 per cent. Therefore, I think that goes along with what Dr. Angell has said regarding attempts to reconstruct the anterior leaflet of the mitral valve. I certainly appreciate Dr. Roe's comments, as he is one of the pioneers in this field. I think his idea about assessing in some sort of semi-quantitative fashion the mobility of the anterior leaflet is a good one. I would suggest that this be included in the form that he outlines or as a good description of the anterior leaflet mobility at the time of operation. Certainly, the patients in his " A " category are those who will have a very good reconstructive result. The " B " category comprises the patients who cause the biggest problems intraoperatively and require the most intraoperative judgment.