- Email: [email protected]
Midterm Results of Mitral Valve Repair: Closed Versus Open Annuloplasty Ring
Dan Spiegelstein, MD, Yaron Moshkovitz, MD, Leonid Sternik, MD, Micha S. Fienberg, MD, Alexander Kogan, MD, Ateret Malachy, MA, and Ehud Raanani MD Department of Cardiac Surgery, Unit of Noninvasive Cardiac Imaging, Chaim Sheba Medical Center (affiliated to the Sackler School of Medicine, Tel-Aviv University, Tel-Aviv), Ramat-Gan, Israel
Background. Closed and open annuloplasty rings are both used for mitral valve repair. This study compared the clinical and echocardiographic results in patients with degenerative mitral disease undergoing MV repair with closed semirigid rings vs open bands. Methods. Between 2004 and 2008, 377 patients (mean age, 59 ⴞ 12 years) underwent mitral valve repair. Valve pathology was degenerative in 273 (72%). Closed rings were used in 163 (60%) and open rings in 110 (40%). Patients had similar characteristics and comorbidities. In addition to annuloplasty, repair techniques included leaflet resection (48% and 77%, p < 0.01), artificial chordal (55% and 36%, p < 0.01), and edge-to-edge repair (4% and 4%, p ⴝ 0.79), in closed and open groups, respectively. Results. One patient in each group died (0.7%). Mean follow-up was 19 ⴞ 14 (closed group) and 34 ⴞ 15 months
(open group; p < 0.01). Freedom from reoperation was 97.5% (closed group) vs 96.5% (open group). At followup, New York Heart Association functional class was similar between groups, and 91% in the closed group and 84% in the open group were free from moderate or severe mitral regurgitation (p ⴝ 0.05). Closed group patients had a longer line of leaflet coaptation (9.1 ⴞ 2.7 mm) vs the open group (7.1 ⴞ 1.9 mm; p < 0.01). Conclusions. Patients with closed semirigid annuloplasty rings demonstrated significantly longer lines of leaflet coaptation and tendency toward better echocardiographic midterm results than patients with open bands and may, therefore, benefit from improved repair durability. (Ann Thorac Surg 2010;90:489 –96) © 2010 by The Society of Thoracic Surgeons
D
we compared the durability of MV repair with a closed semirigid annuloplasty ring (closed group) vs an open annuloplasty band (open group) in patients undergoing MV repair for degenerative MV disease.
egenerative mitral valve (MV) disease is currently the most common cause of mitral regurgitation (MR) in the Western world [1]. MV repair is considered superior to replacement because it offers improved operative and long-term survival, greater regression of left ventricular dimensions, maintenance of left ventricular function, and freedom from long-term anticoagulation [2– 4]. A better understanding of the structure, function and pathology of the MV during the last few decades has improved the surgical results of degenerative MV repair, with operative mortality reduced to less than 1% and excellent long-term survival [3, 5]. Annular enlargement is present in patients with degenerative disease, with the dilation usually occurring only along the posterior MV annulus. Annuloplasty is performed to correct annular dilatation, increase leaflet coaptation, and prevent future annular dilatation. Reconstruction of the mitral annulus is the basis of surgical repair with all other valve repair techniques (leaflet resection, artificial chordal, etc). Various annuloplasty ring designs are available: flexible, semirigid or rigid, closed or open. However, controversy still exists about the significance of the ring type on the immediate and long-term results of MV repair. Thus,
Accepted for publication March 26, 2010. Address correspondence to Dr Raanani, Department of Cardiac Surgery, Chaim Sheba Medical Center, Tel-Hashomer, 52621 Ramat-Gan, Israel; e-mail: [email protected]
© 2010 by The Society of Thoracic Surgeons Published by Elsevier Inc
Material and Methods This is a retrospective, nonrandomized review of a prospective follow-up of all patients who underwent MV repair due to degenerative MV disease. The Institutional Review Board approved the study and granted a waiver of patient consent.
Patients Between January 2004 and December 2008, 377 patients underwent MV repair at our medical center. Of these, 273 (72%) had degenerative disease and formed our study cohort. Closed annuloplasty was performed in 163 patients (60%) and open annuloplasty in 110 (40%). Patients were a mean age of 59 ⫾ 12 years (range, 20 to 88 years). The posterior leaflet was involved in 194 patients (71%), and bileaflet or anterior leaflet pathology was present in 79 (29%). Posterior leaflet pathology was more prevalent in the open ring group (78%) than in the closed group (66%; p ⫽ 0.03; Fig 1). Previous cardiac operations and asymptomatic patients, defined as New York Heart Association (NYHA) functional class I, were more prevalent in the open ring group. There were no differences in 0003-4975/$36.00 doi:10.1016/j.athoracsur.2010.03.070
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using the closed annuloplasty rings more frequently, based on anticipated possible improved repair durability from this technique. As a result, follow-up is shorter for these patients. ADULT CARDIAC
Surgical Management
Fig 1. Flow chart shows the cohort of 273 patients in this study.
gender, ejection fraction, and other preoperative characteristics (Table 1). The mean additive and logistic European System for Cardiac Operative Risk Evaluation was similar between the closed (3.5 ⫾ 2.5 and 3.9% ⫾ 5.1%) and open (3.9 ⫾ 2.7 and 4.5% ⫾ 8.0%) groups. During the latter part of the study period, we began
All patients underwent elective procedures performed by 3 surgeons: 224 patients (82%) by the median sternotomy approach and 49 (18%) by a minimal invasive approach using the port-access technique. Intraoperative transesophageal echocardiography was performed in all patients to evaluate valvular and ventricular function before and after the operation. All operations were performed with the use of mild hypothermic cardiopulmonary bypass, and myocardial protection was achieved by intermittent cold crystalloid cardioplegia. The surgical repair was performed by exposing the MV through the traditional left atrial incision, parallel to the interatrial sulcus. The incision was started from the superior vena cava and extended inferiorly to the mitral annulus. A Carpentier-Edwards Physio ring (Edwards Lifesciences LLC, Irvine, CA) was used in 149 patients (91%) in the closed group, and a Cosgrove-Edwards band (Edwards Lifesciences LLC) was used in 98 patients (89%) in the open group. Average ring size was similar, at 33 ⫾ 3 in the closed group and 32 ⫾ 2 in the open group (p ⫽ .43).
Table 1. Patient Characteristics Characteristica Age, years Males Females NYHA I (asymptomatic) II III IV Ejection fraction Previous cardiac operation Diabetes mellitus Hypertension COPD Chronic renal failure Hyperlipidemia Stroke Pulmonary hypertension Peripheral vascular disease EuroSCORE additive EuroSCORE logistic, % a
All Patients (n ⫽ 273)
Closed Group (n ⫽ 163)
Open Group (n ⫽ 110)
59 ⫾ 12 211 (77) 62 (23)
58 ⫾ 12 123 (75) 40 (25)
60 ⫾ 12 88 (80) 22 (20)
0.16 0.38
84 (31) 87 (32) 96 (35) 5 (2) 0.59 ⫾ 0.09 29 (11)
39 (24) 62 (38) 59 (36) 3 (2) 0.59 ⫾ 0.08 10 (6)
45 (41) 25 (23) 37 (34) 2 (2) 0.58 ⫾ 0.11 19 (17)
0.01
24 (9) 130 (48) 6 (2) 15 (6) 82 (30) 10 (4) 17 (6) 5 (2)
9 (6) 80 (49) 3 (2) 10 (6) 51 (32) 4 (3) 15 (9) 1 (1)
15 (14) 50 (46) 3 (3) 5 (5) 31 (28) 6 (6) 2 (2) 4 (4)
0.02 0.57 0.62 0.57 0.59 0.19 0.01 0.07
3.64 ⫾ 2.59 4.17 ⫾ 6.56
3.45 ⫾ 2.45 3.93 ⫾ 5.13
3.87 ⫾ 2.74 4.47 ⫾ 8.02
0.28 0.58
p Value
0.78 ⬍0.01
Continuous data are presented as mean ⫾ standard deviation and categoric data as number (%).
COPD ⫽ chronic obstructive pulmonary disease; Heart Association.
EuroSCORE ⫽ European System for Cardiac Operative Risk Evaluation;
NYHA ⫽ New York
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Table 2. Operative Data
Operative time, min CPB, min Cross-clamp time, min Concomitant procedures Any procedure CABG Tricuspid valve Aortic valve Aorta Maze Minimally invasive MV pathology Posterior Anterior/bileaflet Leaflet resection Artificial chordal Edge-to-edge CABG ⫽ coronary artery bypass graft;
Closed Group (n ⫽ 163) Mean ⫾ SD
Open Group (n ⫽ 110) Mean ⫾ SD
281 ⫾ 75 113 ⫾ 38 86 ⫾ 28 No. (%)
277 ⫾ 73 112 ⫾ 40 86 ⫾ 28 No. (%)
287 ⫾ 79 114 ⫾ 35 86 ⫾ 26 No. (%)
0.40 0.73 0.93
109 (40) 44 (16) 39 (14) 4 (1.5) 2 (1) 36 (13) 49 (18)
68 (42) 32 (20) 26 (16) 1 (1) 1 (1) 18 (11) 24 (15)
41 (37) 12 (11) 13 (12) 3 (3) 1 (1) 18 (16) 25 (23)
0.46 0.06 0.34 0.15 0.78 0.20 0.09
194 (71) 79 (29) 163 (60) 128 (47) 11 (4)
108 (66) 55 (34) 78 (48) 89 (55) 7 (4)
86 (78) 24 (22) 85 (77) 39 (36) 4 (4)
0.03
CPB ⫽ cardiopulmonary bypass;
MV ⫽ mitral valve;
p Value
⬍0.01 ⬍0.01 0.79
SD ⫽ standard deviation.
Table 3. Early and Late Results Resulta Hospital mortality Major complications CVA TIA Low cardiac output Renal failure/dialysis Intraaortic balloon pump Pacemaker Late mortality Reoperation on MV Mean follow-up, mon Ejection fraction Total MACEb CVA TIA MI Anticoagulationrelated bleeding
All Patients (n ⫽ 273)
Closed Group (n ⫽ 163)
Open Group (n ⫽ 110)
2 (1) 9 (3) 3 (2) 1 (0.5) 2 (1) 5 (2) 2 (1)
1 (1) 3 (2) 2 (2) 1 (1) 0 1 (1) 0
1 (1) 6 (6) 1 (1) 0 2 (2) 4 (4) 2 (2)
5 (2) 4 (2) 8 (3) 25 ⫾ 16 0.55 ⫾ 0.07 13 (5) 7 (3) 26 (10) 2 (1) 3 (1)
1 (1) 0 4 (3) 19 ⫾ 14 0.55 ⫾ 0.07 2 (1) 2 (1) 20 (13) 0 1 (1)
4 (4) 4 (4) 4 (4) 34 ⫾ 15 0.55 ⫾ 0.07 11 (10) 5 (5) 6 (6) 2 (2) 2 (2)
a Continuous data expressed as mean ⫾ standard deviation; categoric data as number (%). MI, CVA.
b
CVA ⫽ cerebrovascular accident;
TIA ⫽ transient ischemic attack.
MI ⫽ myocardial infarction;
MV ⫽ mitral valve;
p Value 0.78 0.10 0.24 0.36 0.13 0.12 0.13 0.12 0.01 0.57 ⬍0.01 0.99 ⬍0.01 0.08 0.06 0.08 0.41
Major adverse cardiac events (MACE) defined as death,
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Valve repair techniques included posterior leaflet resection (60%), artificial chordal (47%), and Alfieri edge-toedge (4%). Repair techniques differed between the groups, depending on leaflet involvement. Anterior or bileaflet pathology was more prevalent in the closed group, and therefore, the artificial chordal technique was used more frequently. Leaflet resection was more common in the open group. Concomitant procedures were performed in 109 patients (40%), demonstrating no differences between the groups. Operative data and surgical techniques are presented in Table 2. After completion of repair and weaning from cardiopulmonary bypass, MR was evaluated by transesophageal echocardiography. Moderate or severe MR was considered unacceptable, and the valve was re-repaired in 10 patients (4%). All patients received anticoagulation with warfarin sodium for 3 months, and permanently if they had atrial fibrillation.
Follow-Up Demographic, echocardiographic, and surgical data were collected from the departmental database or other institutional medical records. Mortality data were retrieved from the official national database, and patients or family members were contacted for clinical follow-up. Follow-up echocardiography data were obtained from the institutional database, patients, or ambulatory medical services. Clinical follow-up was completed in 260 of the 267 survivors (97.5%), and late echocardiographic data were obtained from 265 of 271 (98%) hospital survivors. Mean follow-up was 25 ⫾ 16 months (range, 1 to 64 months) and was significantly longer in the open group (35 ⫾ 15 months) than in the closed group (19 ⫾ 14; p ⬍ 0.01). As noted, closed semirigid rings were used more frequently during the latter half of the study period, thereby shortening the length of follow-up in those patients. Total follow-up was 528 patient-years.
Fig 3. Coaptation length analysis is shown (left) preoperatively and (right) postoperatively for the (top) open annuloplasty and (bottom) closed annuloplasty groups.
Data Analysis The data for this review were derived from the database of the Cardiac Surgery Department. Complications were reported according to the “Guidelines for Reporting Mortality and Morbidity after Cardiac Valve Interventions” [6]. MR grades were classified according to the Society of Thoracic Surgeons guidelines (http:// www.sts.org/file/CoreDef241Book.pdf) as grade 0, no MR; grade 1, trivial MR; grade 2, mild MR; grade 3, moderate MR; and grade 4, severe MR. All statistical analyses were performed with SPSS 16.0 software (SPSS Inc, Chicago, IL). Group statistics were expressed as mean ⫾ 1 standard deviation. Continuous variables were compared using the t test, and categoric variables using the 2 test. Predictors for recurrent MR were determined by multivariate analysis. Survival and reoperation information for the two groups was compared by Kaplan-Meier curves with the log-rank test. Values of p ⬍ 0.05 were considered significant.
Results Early Results
Fig 2. Kaplan-Meier analysis shows freedom from mitral valve reoperation in the open annuloplasty (dashed line) and closed annuloplasty (solid line) patients.
Mean operative times (277 ⫾ 73 vs 287 ⫾ 79 minutes), cardiopulmonary bypass times (112 ⫾ 40 vs 114 ⫾ 35 minutes), and aortic clamp times (86 ⫾ 28 vs 86 ⫾ 26 minutes) were similar between the closed and open groups, respectively (p ⫽ 0.4, p ⫽ 0.73, and p ⫽ 0.93, respectively). There were 2 hospital deaths among the 273 patients (0.7%), one in each group (p ⫽ 0.78). Early major complications were similar between the groups (6% vs 2%, open and closed groups, respectively,
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Table 4. Echocardiographic Results
Freedom from grade 3–4 MR None/trivial Mild Moderate Severe MV area cm2 MV peak mm Hg MV mean mm Hg LVEDD LVESD Coaptation length, mm MV annulus AP diameter, mm a
Closed Group (n ⫽ 158) No. (%)
30 (12) 112 (41) 126 (47) 26 (10) 4 (2)
13 (91) 71 (45) 74 (47) 11 (7) 2 (1)
Mean ⫾ SD 2.5 ⫾ 0.8 7.1 ⫾ 2.5 3.2 ⫾ 1.1 5.0 ⫾ 0.6 3.2 ⫾ 0.7 (n ⫽ 87) 7.9 ⫾ 2.4 35.7 ⫾ 4.8
Mean ⫾ SD 2.5 ⫾ 0.8 7.2 ⫾ 2.6 3.3 ⫾ 1.2 5.0 ⫾ 0.6 3.3 ⫾ 0.8 (n ⫽ 36) 9.1 ⫾ 2.7 35.8 ⫾ 3.6
Open Group (n ⫽ 107) No. (%) 17 (84) 38 (35) 52 (49) 15 (14) 2 (2) Mean ⫾ SD 2.5 ⫾ 0.8 6.9 ⫾ 2.3 2.9 ⫾ 0.9 4.9 ⫾ 0.6 3.1 ⫾ 0.8 (n ⫽ 51) 7.1 ⫾ 1.9 35.7 ⫾ 5.6
p Value 0.05 0.19
0.94 0.48 0.05 0.10 0.11 ⬍0.005 0.89
Continuous data expressed as mean ⫾ standard deviation; categoric data as number (%).
AP ⫽ anterior posterior; LVEDD ⫽ left ventricular end diastolic diameter; regurgitation; MV ⫽ mitral valve; SD ⫽ standard deviation.
p ⫽ .1). All early postoperative complications are presented in Table 3. Early postoperative echocardiographic results for MR in the closed and open groups, respectively, were as follows: 86% vs 82% had no or trivial MR, 12% vs 16% had mild MR, and 2% vs 2% had mild to moderate MR.
Late Results At follow-up, there were 4 late deaths (2%), all from the open group. Two were valve-related (acute respiratory failure and intracranial hemorrhage), and 2 were nonvalve-related. Kaplan-Meier analysis for late survival at 4 years was 99% ⫾ 1% in the closed group and 93% ⫾ 3% in the open group (p ⫽ .12). Eight patients (3%) required MV reoperations due to recurrent severe MR: 4 (3%) in the closed group and 4 (4%) in the open group (p ⫽ .57). Four reoperations were performed during the first 3 months after the initial operation, and four occurred within the first year. Of these 8 patients, 7 underwent repeat repair of the MV, and the MV was replaced in 1 patient. Freedom from reoperation in all patients was 95% ⫾ 3% at 3 years (94% ⫾ 4% in the closed group, 96% ⫾ 2% in the open group; log rank, p ⫽ .88; Fig 2). Mechanisms of repair failures in the 8 reoperated-on patients were artificial chordal failure in 6 (75%), recurrent prolapse in 2 (50%), retracted posterior leaflet after resection in 1 (12.5%), and ring dehiscence in 1 (12.5%). No operative deaths occurred among the patients who underwent reoperation. NYHA class was similar between the groups at the last follow-up: 88% were in NYHA class I/II and 12% were in class III/IV in the closed group, while 89% were in NYHA class I/II and 11% in class III/IV in the open group (NS). Thromboembolic complications (7 strokes and 26 transient
LVESD ⫽ left ventricular end systolic diameter;
MR ⫽ mitral
ischemic attacks) occurred in 33 patients (13%). Anticoagulation-related hemorrhage occurred in 3 patients (1.1%). Late echocardiography data are presented in Table 4. Mean MR was 1.4 ⫾ 0.9 in the closed group and 1.6 ⫾ 0.9 in the open group (p ⫽ .05). Recurrence of grade 3 to 4 MR occurred in 30 patients (12%), of whom 8 underwent reoperations. Freedom from grade 3 to 4 MR was 91% in the closed group and 84% in the open group (p ⫽ .05). There were no differences between the groups in valve area and gradient across the MV. Of the total 265 late follow-up echocardiographic records, 87 examinations were done in the echocardiography laboratory of our medical center. These 87 examinations were re-reviewed by a single examiner, blinded to the surgical technique, who measured MV anteriorposterior diameter, coaptation length, and annulus to coaptation point. All measurements were done in the same transthoracic echocardiogram examination: 4-chamber apical view (Fig 3). The mean follow-up duration between the 87 patients with coaptation data and the 178 patients without coaptation data was similar, with no statistical differences. A significantly longer line of MV leaflet coaptation was found in the closed (9.1 ⫾ 2.7 mm) group than in the open group (7.1 ⫾ 1.9 mm; p ⬍ 0.01). There were no differences in the anterior-posterior diameter and annulus to coaptation point distance. We further analyzed the coaptation line in the subgroups of isolated posterior pathology (58 patients) and anterior/bileaflet pathology (29 patients), and the coaptation length was significantly longer in the closed group in both subgroups. Causes for late repair failure (grade 3 to 4 MR), were progression of degenerative disease or surgical technique failure. These failures included artificial chordal
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failure, recurrent prolapse, ring dehiscence, and insufficient coaptation. According to univariant analysis, the use of the open annuloplasty ring was the only predictor for late recurrence of grade 3 to 4 MR. Other variables, such as preoperative characteristics and repair techniques (leaflet resection and artificial chordal), did not predict late recurrence of significant MR.
Comment Although MV repair results are superior to MV replacement [3], and repair is considered the procedure of choice for degenerative severe MR disease, the long-term results are still suboptimal. Gillinov and Cosgrove [2] reported 93% freedom from reoperation at 10 years, with a mean follow-up of 4.0 ⫾ 2.9 years. David and colleagues [7] reported 94% freedom from reoperation and 89% freedom from recurrent severe MR at 12 years. Recent publications reveal similar results, with freedom from reoperation and moderate or severe MR exceeding 95% and 77%, respectively [8, 9]. The present study demonstrates comparable results, although length of follow-up was shorter. Predictors for reoperation and moderatesevere MR recurrence are anterior leaflet prolapse, lack of annuloplasty, concomitant procedures, left ventricular dysfunction, advanced age, and higher NYHA [7, 9 –11]. Common valve repair techniques include posterior leaflet resection, sliding repair, chordal transfer, chordal shortening, Alfieri edge-to-edge, and artificial chordal implantation. Valve annuloplasty is an important component of MV repair in almost all MV pathologies. Its overall role is to reduce both the size of the annulus and tension on the sutures, increase leaflet coaptation, and reinforce the annulus to prevent future dilatation, while concurrently providing flexibility and mobility. It is also known that annuloplasty improves valve repair durability [2, 12]. Although various annuloplasty techniques are in use, and good results have been reported with all of them, the optimal choice is still debated. Several studies have examined the effect of annuloplasty type on repair durability and left ventricular function, but no one type has been shown to be superior to another. David and colleagues [13] showed better systolic function in patients with a flexible ring on short-term follow up. Gillinov and Cosgrove [11] reported equivalent midterm results when posterior was compared with closed annuloplasty [11]. Chang and colleagues [14] enrolled 356 patients to a randomized controlled trial and compared a rigid ring with a closed flexible ring, showing similar long-term outcomes between the groups. Annuloplasty type was related neither to early nor late clinical and echocardiographic results. Our study suggests that closed rings may be more advantageous than posterior bands in terms of less recurrent moderate-severe MR. We have used the closed annuloplasty ring more frequently in recent years, based on our observation that closed semi-rigid ring resulted in increased coaptation length and the perception that this could improve repair durability. Coaptation between valve leaflets is one of the key
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points of MV repair, and the importance of coaptation length has also been recognized in regulating MR [15]. Although no reports to date have described the optimal length of coaptation in degenerative MV repair, research has shown that coaptation length may affect repair durability in patients with ischemic MR [16]. It is reasonable to assume that a longer coaptation line could also improve durability and long-term outcome of MV repair in degenerative MV disease. Bax and colleagues [17] demonstrated excellent results of MV annuloplasty and coronary artery bypass grafting with an 8-mm coaptation length in ischemic MV repair. The mean coaptation length in our study was 9 mm in the closed ring group and 7 mm in the open band group. This 2-mm difference may be of significance in terms of late MR recurrence, which was favorable in the closed ring patients. In our study, the length of MV leaflet coaptation was longer in the closed ring group in patients with isolated posterior, isolated anterior, or bileaflet pathology. It is noteworthy that in instances of isolated posterior leaflet prolapse, leaflet resection was less common in the closed group (63%) than in the open group (85%, p ⫽ .07). It is therefore reasonable to conclude that not only closed annuloplasty type but also “less” resection of the posterior leaflet could improve the coaptation surface, as was recently published by others [18, 19]. Our study shows a tendency towards better echocardiographic results using closed semirigid rather than open flexible ring annuloplasty. The lower rate of recurrent MR in the closed group did not translate to better clinical outcomes (NYHA class and reoperation rate), but this could have been due to the short follow-up, which precluded evaluation of the long-term effects of the echocardiographic results on clinical outcome. In accord with the present study, however, significant recurrent MR tends to occur early postoperatively [20], so it is unlikely to assume that the trend we observed in our limited follow-up period would change dramatically in the long-term. It is noteworthy that in the closed ring group, where patients demonstrated a tendency toward better echocardiographic midterm results compared with their open ring counterparts, anterior or bileaflet pathology was more common, a factor that several previous publications have shown is a predictor for early and late repair failure. The closed rigid ring may impair the valve’s natural motion, distort the anterior leaflet, reduce orifice area, increase gradient across the valve, and increase the risk of systolic anterior motion (SAM). In our series the mean gradient was slightly higher in the closed group, with no significant differences in the other variables (Table 4). The risk of SAM after MV repair is caused by anterior displacement of the leaflet coaptation point, secondary to excessive height or redundant tissue of the posterior leaflet [21]. SAM is associated with the use of closed rigid annuloplasty rings but may also occur with open rings or without the use of any ring [22, 23]. We found no differences in SAM prevalence between closed and open annuloplasty. However, we preferred to use the open
ring in those patients who were at higher risk of SAM (small ventricle, tall posterior leaflet).
Study Limitations This was a nonrandomized study with a limited midterm follow-up period, which slightly varied in length between the two groups. Although echocardiographic follow-up was complete, only some of the patients were available for a more detailed analysis, which included coaptation length, anterior-posterior diameter, and annulus to coaptation point.
Conclusions In this retrospective study, we found tendency towards less recurrent significant MR, with longer lengths of leaflet coaptation in the closed ring annuloplasty group. The use of closed rings compared with open bands could therefore improve long-term quality of MV repair. To reach more definite conclusions regarding a relationship between the type of MV annuloplasty, the length of coaptation, and the recurrence of MR, evaluation of a larger patient cohort with more comprehensive early and late echocardiographic follow-up is recommended. We thank Maya First for her expert statistical analysis and Vivienne York for her valuable editorial assistance.
References 1. Avierinos JF, Gersh BJ, Melton LJ 3rd, et al. Natural history of asymptomatic mitral valve prolapse in the community. Circulation 2002;106:1355– 61. 2. Gillinov AM, Cosgrove DM, Blackstone EH, et al. Durability of mitral valve repair for degenerative disease. J Thorac Cardiovasc Surg 1998;116:734 – 43. 3. Mohty D, Orszulak TA, Schaff HV, Avierinos JF, Tajik JA, Enriquez-Sarano M. Very long-term survival and durability of mitral valve repair for mitral valve prolapse. Circulation 2001;104:I1–I7. 4. Suri RM, Schaff HV, Dearani JA, et al. Survival advantage and improved durability of mitral repair for leaflet prolapse subsets in the current era. Ann Thorac Surg 2006;82:819 –26. 5. Enriquez-Sarano M, Orszulak TA, Schaff HV, Abel MD, Tajik AJ, Frye RL. Mitral regurgitation: a new clinical perspective. Mayo Clinic Proceedings 1997;72:1034 – 43. 6. Akins CW, Miller DC, Turina MI, et al. Guidelines for reporting mortality and morbidity after cardiac valve interventions. Ann Thorac Surg 2008;85:1490 –5. 7. David TE, Ivanov J, Armstrong S, Christie D, Rakowski H. A comparison of outcomes of mitral valve repair for degenerative disease with posterior, anterior, and bileaflet prolapse. J Thorac Cardiovasc Surg 2005;130:1242–9.
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8. Miura T, Eishi K, Yamachika S, et al. Mitral valve repair for degenerative disease with leaflet prolapse: to improve longterm outcomes. Gen Thorac Cardiovasc Surg 2009;57:10 –21. 9. Stevens LM, Basmadjian AJ, Bouchard D, et al. Late echocardiographic and clinical outcomes after mitral valve repair for degenerative disease. J Cardiac Surg 2010;25:9 –15. 10. Chenot F, Montant P, Vancraeynest D, et al. Long-term clinical outcome of mitral valve repair in asymptomatic severe mitral regurgitation. Eur J Cardiothorac Surg 2009;36: 539 – 45. 11. Gillinov AM, Cosgrove DM. Mitral valve repair for degenerative disease. J Heart Valve Dis 2002;11(suppl 1):S15–20. 12. Cohn LH, Couper GS, Aranki SF, Rizzo RJ, Kinchla NM, Collins JJ Jr. Long-term results of mitral valve reconstruction for regurgitation of the myxomatous mitral valve. J Thorac Cardiovasc Surg 1994;107:143–50. 13. David TE, Komeda M, Pollick C, Burns RJ. Mitral valve annuloplasty: the effect of the type on left ventricular function. Ann Thorac Surg 1989;47:524 –7. 14. Chang BC, Youn YN, Ha JW, Lim SH, Hong YS, Chung N. Long-term clinical results of mitral valvuloplasty using flexible and rigid rings: a prospective and randomized study. J Thorac Cardiovasc Surg 2007;133:995–1003. 15. Yamauchi T, Taniguchi K, Kuki S, et al. Evaluation of the mitral valve leaflet morphology after mitral valve reconstruction with a concept “coaptation length index.” J Cardiac Surg 2004;19:535– 8. 16. Kuwahara E, Otsuji Y, Iguro Y, et al. Mechanism of recurrent/persistent ischemic/functional mitral regurgitation in the chronic phase after surgical annuloplasty: importance of augmented posterior leaflet tethering. Circulation 2006;114: I529 –34. 17. Bax JJ, Braun J, Somer ST, et al. Restrictive annuloplasty and coronary revascularization in ischemic mitral regurgitation results in reverse left ventricular remodeling. Circulation 2004;110:II103– 8. 18. Perier P, Hohenberger W, Lakew F, Batz G, Urbanski P, Zacher M, Diegeler A. Toward a new paradigm for the reconstruction of posterior leaflet prolapse: midterm results of the “respect rather than resect” approach. Ann Thorac Surg 2008;86:718 –25. 19. Falk V, Seeburger J, Czesla M, et al. How does the use of polytetrafluoroethylene neochordae for posterior mitral valve prolapse (loop technique) compare with leaflet resection? A prospective randomized trial. J Thorac Cardiovasc Surg 2008;136:1205. 20. Meyer MA, von Segesser LK, Hurni M, Stumpe F, Eisa K, Ruchat P. Long-term outcome after mitral valve repair: a risk factor analysis. Eur J Cardiothorac Surg 2007;32:301–7. 21. Lee KS, Stewart WJ, Lever HM, Underwood PL, Cosgrove DM. Mechanism of outflow tract obstruction causing failed mitral valve repair. Anterior displacement of leaflet coaptation. Circulation 1993;88:II24 –9. 22. Kupferschmid JP, Carr T, Connelly GP, Shemin RJ. Systolic anterior motion of the mitral valve after valve repair without an annular ring. Ann Thorac Surg 1994;57:484 – 6. 23. Lopez JA, Schnee M, Gaos CM, Wilansky S. Left ventricular outflow tract obstruction and hemolytic anemia after mitral valve repair with a Duran ring. Ann Thorac Surg 1994;58:876 –7.
INVITED COMMENTARY Spiegelstein and associates [1] have addressed an important question: Should complete rings be used for the repair of mitral regurgitation from degenerative disease? Strong clinical evidence supports the use of closed, rigid or semirigid annuloplasty rings for myopathic (regional ischemic and global cardiomyopathic) disease [2]. Similar findings for degenerative disease have not been reported. © 2010 by The Society of Thoracic Surgeons Published by Elsevier Inc
The present study by Spiegelstein and associates [1] concludes that the use of closed rings is associated with improved leaflet coaptation and freedom from recurrent regurgitation for patients with degenerative disease. A strength of this work is the admirable 98% echocardiographic follow-up; however, there are concerns that transthoracic echo cannot measure coaptation at the level 0003-4975/$36.00 doi:10.1016/j.athoracsur.2010.05.006
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Background. Closed and open annuloplasty rings are both used for mitral valve repair. This study compared the clinical and echocardiographic results in patients with degenerative mitral disease undergoing MV repair with closed semirigid rings vs open bands. Methods. Between 2004 and 2008, 377 patients (mean age, 59 ⴞ 12 years) underwent mitral valve repair. Valve pathology was degenerative in 273 (72%). Closed rings were used in 163 (60%) and open rings in 110 (40%). Patients had similar characteristics and comorbidities. In addition to annuloplasty, repair techniques included leaflet resection (48% and 77%, p < 0.01), artificial chordal (55% and 36%, p < 0.01), and edge-to-edge repair (4% and 4%, p ⴝ 0.79), in closed and open groups, respectively. Results. One patient in each group died (0.7%). Mean follow-up was 19 ⴞ 14 (closed group) and 34 ⴞ 15 months
(open group; p < 0.01). Freedom from reoperation was 97.5% (closed group) vs 96.5% (open group). At followup, New York Heart Association functional class was similar between groups, and 91% in the closed group and 84% in the open group were free from moderate or severe mitral regurgitation (p ⴝ 0.05). Closed group patients had a longer line of leaflet coaptation (9.1 ⴞ 2.7 mm) vs the open group (7.1 ⴞ 1.9 mm; p < 0.01). Conclusions. Patients with closed semirigid annuloplasty rings demonstrated significantly longer lines of leaflet coaptation and tendency toward better echocardiographic midterm results than patients with open bands and may, therefore, benefit from improved repair durability. (Ann Thorac Surg 2010;90:489 –96) © 2010 by The Society of Thoracic Surgeons
D
we compared the durability of MV repair with a closed semirigid annuloplasty ring (closed group) vs an open annuloplasty band (open group) in patients undergoing MV repair for degenerative MV disease.
egenerative mitral valve (MV) disease is currently the most common cause of mitral regurgitation (MR) in the Western world [1]. MV repair is considered superior to replacement because it offers improved operative and long-term survival, greater regression of left ventricular dimensions, maintenance of left ventricular function, and freedom from long-term anticoagulation [2– 4]. A better understanding of the structure, function and pathology of the MV during the last few decades has improved the surgical results of degenerative MV repair, with operative mortality reduced to less than 1% and excellent long-term survival [3, 5]. Annular enlargement is present in patients with degenerative disease, with the dilation usually occurring only along the posterior MV annulus. Annuloplasty is performed to correct annular dilatation, increase leaflet coaptation, and prevent future annular dilatation. Reconstruction of the mitral annulus is the basis of surgical repair with all other valve repair techniques (leaflet resection, artificial chordal, etc). Various annuloplasty ring designs are available: flexible, semirigid or rigid, closed or open. However, controversy still exists about the significance of the ring type on the immediate and long-term results of MV repair. Thus,
Accepted for publication March 26, 2010. Address correspondence to Dr Raanani, Department of Cardiac Surgery, Chaim Sheba Medical Center, Tel-Hashomer, 52621 Ramat-Gan, Israel; e-mail: [email protected]
© 2010 by The Society of Thoracic Surgeons Published by Elsevier Inc
Material and Methods This is a retrospective, nonrandomized review of a prospective follow-up of all patients who underwent MV repair due to degenerative MV disease. The Institutional Review Board approved the study and granted a waiver of patient consent.
Patients Between January 2004 and December 2008, 377 patients underwent MV repair at our medical center. Of these, 273 (72%) had degenerative disease and formed our study cohort. Closed annuloplasty was performed in 163 patients (60%) and open annuloplasty in 110 (40%). Patients were a mean age of 59 ⫾ 12 years (range, 20 to 88 years). The posterior leaflet was involved in 194 patients (71%), and bileaflet or anterior leaflet pathology was present in 79 (29%). Posterior leaflet pathology was more prevalent in the open ring group (78%) than in the closed group (66%; p ⫽ 0.03; Fig 1). Previous cardiac operations and asymptomatic patients, defined as New York Heart Association (NYHA) functional class I, were more prevalent in the open ring group. There were no differences in 0003-4975/$36.00 doi:10.1016/j.athoracsur.2010.03.070
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using the closed annuloplasty rings more frequently, based on anticipated possible improved repair durability from this technique. As a result, follow-up is shorter for these patients. ADULT CARDIAC
Surgical Management
Fig 1. Flow chart shows the cohort of 273 patients in this study.
gender, ejection fraction, and other preoperative characteristics (Table 1). The mean additive and logistic European System for Cardiac Operative Risk Evaluation was similar between the closed (3.5 ⫾ 2.5 and 3.9% ⫾ 5.1%) and open (3.9 ⫾ 2.7 and 4.5% ⫾ 8.0%) groups. During the latter part of the study period, we began
All patients underwent elective procedures performed by 3 surgeons: 224 patients (82%) by the median sternotomy approach and 49 (18%) by a minimal invasive approach using the port-access technique. Intraoperative transesophageal echocardiography was performed in all patients to evaluate valvular and ventricular function before and after the operation. All operations were performed with the use of mild hypothermic cardiopulmonary bypass, and myocardial protection was achieved by intermittent cold crystalloid cardioplegia. The surgical repair was performed by exposing the MV through the traditional left atrial incision, parallel to the interatrial sulcus. The incision was started from the superior vena cava and extended inferiorly to the mitral annulus. A Carpentier-Edwards Physio ring (Edwards Lifesciences LLC, Irvine, CA) was used in 149 patients (91%) in the closed group, and a Cosgrove-Edwards band (Edwards Lifesciences LLC) was used in 98 patients (89%) in the open group. Average ring size was similar, at 33 ⫾ 3 in the closed group and 32 ⫾ 2 in the open group (p ⫽ .43).
Table 1. Patient Characteristics Characteristica Age, years Males Females NYHA I (asymptomatic) II III IV Ejection fraction Previous cardiac operation Diabetes mellitus Hypertension COPD Chronic renal failure Hyperlipidemia Stroke Pulmonary hypertension Peripheral vascular disease EuroSCORE additive EuroSCORE logistic, % a
All Patients (n ⫽ 273)
Closed Group (n ⫽ 163)
Open Group (n ⫽ 110)
59 ⫾ 12 211 (77) 62 (23)
58 ⫾ 12 123 (75) 40 (25)
60 ⫾ 12 88 (80) 22 (20)
0.16 0.38
84 (31) 87 (32) 96 (35) 5 (2) 0.59 ⫾ 0.09 29 (11)
39 (24) 62 (38) 59 (36) 3 (2) 0.59 ⫾ 0.08 10 (6)
45 (41) 25 (23) 37 (34) 2 (2) 0.58 ⫾ 0.11 19 (17)
0.01
24 (9) 130 (48) 6 (2) 15 (6) 82 (30) 10 (4) 17 (6) 5 (2)
9 (6) 80 (49) 3 (2) 10 (6) 51 (32) 4 (3) 15 (9) 1 (1)
15 (14) 50 (46) 3 (3) 5 (5) 31 (28) 6 (6) 2 (2) 4 (4)
0.02 0.57 0.62 0.57 0.59 0.19 0.01 0.07
3.64 ⫾ 2.59 4.17 ⫾ 6.56
3.45 ⫾ 2.45 3.93 ⫾ 5.13
3.87 ⫾ 2.74 4.47 ⫾ 8.02
0.28 0.58
p Value
0.78 ⬍0.01
Continuous data are presented as mean ⫾ standard deviation and categoric data as number (%).
COPD ⫽ chronic obstructive pulmonary disease; Heart Association.
EuroSCORE ⫽ European System for Cardiac Operative Risk Evaluation;
NYHA ⫽ New York
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Table 2. Operative Data
Operative time, min CPB, min Cross-clamp time, min Concomitant procedures Any procedure CABG Tricuspid valve Aortic valve Aorta Maze Minimally invasive MV pathology Posterior Anterior/bileaflet Leaflet resection Artificial chordal Edge-to-edge CABG ⫽ coronary artery bypass graft;
Closed Group (n ⫽ 163) Mean ⫾ SD
Open Group (n ⫽ 110) Mean ⫾ SD
281 ⫾ 75 113 ⫾ 38 86 ⫾ 28 No. (%)
277 ⫾ 73 112 ⫾ 40 86 ⫾ 28 No. (%)
287 ⫾ 79 114 ⫾ 35 86 ⫾ 26 No. (%)
0.40 0.73 0.93
109 (40) 44 (16) 39 (14) 4 (1.5) 2 (1) 36 (13) 49 (18)
68 (42) 32 (20) 26 (16) 1 (1) 1 (1) 18 (11) 24 (15)
41 (37) 12 (11) 13 (12) 3 (3) 1 (1) 18 (16) 25 (23)
0.46 0.06 0.34 0.15 0.78 0.20 0.09
194 (71) 79 (29) 163 (60) 128 (47) 11 (4)
108 (66) 55 (34) 78 (48) 89 (55) 7 (4)
86 (78) 24 (22) 85 (77) 39 (36) 4 (4)
0.03
CPB ⫽ cardiopulmonary bypass;
MV ⫽ mitral valve;
p Value
⬍0.01 ⬍0.01 0.79
SD ⫽ standard deviation.
Table 3. Early and Late Results Resulta Hospital mortality Major complications CVA TIA Low cardiac output Renal failure/dialysis Intraaortic balloon pump Pacemaker Late mortality Reoperation on MV Mean follow-up, mon Ejection fraction Total MACEb CVA TIA MI Anticoagulationrelated bleeding
All Patients (n ⫽ 273)
Closed Group (n ⫽ 163)
Open Group (n ⫽ 110)
2 (1) 9 (3) 3 (2) 1 (0.5) 2 (1) 5 (2) 2 (1)
1 (1) 3 (2) 2 (2) 1 (1) 0 1 (1) 0
1 (1) 6 (6) 1 (1) 0 2 (2) 4 (4) 2 (2)
5 (2) 4 (2) 8 (3) 25 ⫾ 16 0.55 ⫾ 0.07 13 (5) 7 (3) 26 (10) 2 (1) 3 (1)
1 (1) 0 4 (3) 19 ⫾ 14 0.55 ⫾ 0.07 2 (1) 2 (1) 20 (13) 0 1 (1)
4 (4) 4 (4) 4 (4) 34 ⫾ 15 0.55 ⫾ 0.07 11 (10) 5 (5) 6 (6) 2 (2) 2 (2)
a Continuous data expressed as mean ⫾ standard deviation; categoric data as number (%). MI, CVA.
b
CVA ⫽ cerebrovascular accident;
TIA ⫽ transient ischemic attack.
MI ⫽ myocardial infarction;
MV ⫽ mitral valve;
p Value 0.78 0.10 0.24 0.36 0.13 0.12 0.13 0.12 0.01 0.57 ⬍0.01 0.99 ⬍0.01 0.08 0.06 0.08 0.41
Major adverse cardiac events (MACE) defined as death,
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Valve repair techniques included posterior leaflet resection (60%), artificial chordal (47%), and Alfieri edge-toedge (4%). Repair techniques differed between the groups, depending on leaflet involvement. Anterior or bileaflet pathology was more prevalent in the closed group, and therefore, the artificial chordal technique was used more frequently. Leaflet resection was more common in the open group. Concomitant procedures were performed in 109 patients (40%), demonstrating no differences between the groups. Operative data and surgical techniques are presented in Table 2. After completion of repair and weaning from cardiopulmonary bypass, MR was evaluated by transesophageal echocardiography. Moderate or severe MR was considered unacceptable, and the valve was re-repaired in 10 patients (4%). All patients received anticoagulation with warfarin sodium for 3 months, and permanently if they had atrial fibrillation.
Follow-Up Demographic, echocardiographic, and surgical data were collected from the departmental database or other institutional medical records. Mortality data were retrieved from the official national database, and patients or family members were contacted for clinical follow-up. Follow-up echocardiography data were obtained from the institutional database, patients, or ambulatory medical services. Clinical follow-up was completed in 260 of the 267 survivors (97.5%), and late echocardiographic data were obtained from 265 of 271 (98%) hospital survivors. Mean follow-up was 25 ⫾ 16 months (range, 1 to 64 months) and was significantly longer in the open group (35 ⫾ 15 months) than in the closed group (19 ⫾ 14; p ⬍ 0.01). As noted, closed semirigid rings were used more frequently during the latter half of the study period, thereby shortening the length of follow-up in those patients. Total follow-up was 528 patient-years.
Fig 3. Coaptation length analysis is shown (left) preoperatively and (right) postoperatively for the (top) open annuloplasty and (bottom) closed annuloplasty groups.
Data Analysis The data for this review were derived from the database of the Cardiac Surgery Department. Complications were reported according to the “Guidelines for Reporting Mortality and Morbidity after Cardiac Valve Interventions” [6]. MR grades were classified according to the Society of Thoracic Surgeons guidelines (http:// www.sts.org/file/CoreDef241Book.pdf) as grade 0, no MR; grade 1, trivial MR; grade 2, mild MR; grade 3, moderate MR; and grade 4, severe MR. All statistical analyses were performed with SPSS 16.0 software (SPSS Inc, Chicago, IL). Group statistics were expressed as mean ⫾ 1 standard deviation. Continuous variables were compared using the t test, and categoric variables using the 2 test. Predictors for recurrent MR were determined by multivariate analysis. Survival and reoperation information for the two groups was compared by Kaplan-Meier curves with the log-rank test. Values of p ⬍ 0.05 were considered significant.
Results Early Results
Fig 2. Kaplan-Meier analysis shows freedom from mitral valve reoperation in the open annuloplasty (dashed line) and closed annuloplasty (solid line) patients.
Mean operative times (277 ⫾ 73 vs 287 ⫾ 79 minutes), cardiopulmonary bypass times (112 ⫾ 40 vs 114 ⫾ 35 minutes), and aortic clamp times (86 ⫾ 28 vs 86 ⫾ 26 minutes) were similar between the closed and open groups, respectively (p ⫽ 0.4, p ⫽ 0.73, and p ⫽ 0.93, respectively). There were 2 hospital deaths among the 273 patients (0.7%), one in each group (p ⫽ 0.78). Early major complications were similar between the groups (6% vs 2%, open and closed groups, respectively,
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Table 4. Echocardiographic Results
Freedom from grade 3–4 MR None/trivial Mild Moderate Severe MV area cm2 MV peak mm Hg MV mean mm Hg LVEDD LVESD Coaptation length, mm MV annulus AP diameter, mm a
Closed Group (n ⫽ 158) No. (%)
30 (12) 112 (41) 126 (47) 26 (10) 4 (2)
13 (91) 71 (45) 74 (47) 11 (7) 2 (1)
Mean ⫾ SD 2.5 ⫾ 0.8 7.1 ⫾ 2.5 3.2 ⫾ 1.1 5.0 ⫾ 0.6 3.2 ⫾ 0.7 (n ⫽ 87) 7.9 ⫾ 2.4 35.7 ⫾ 4.8
Mean ⫾ SD 2.5 ⫾ 0.8 7.2 ⫾ 2.6 3.3 ⫾ 1.2 5.0 ⫾ 0.6 3.3 ⫾ 0.8 (n ⫽ 36) 9.1 ⫾ 2.7 35.8 ⫾ 3.6
Open Group (n ⫽ 107) No. (%) 17 (84) 38 (35) 52 (49) 15 (14) 2 (2) Mean ⫾ SD 2.5 ⫾ 0.8 6.9 ⫾ 2.3 2.9 ⫾ 0.9 4.9 ⫾ 0.6 3.1 ⫾ 0.8 (n ⫽ 51) 7.1 ⫾ 1.9 35.7 ⫾ 5.6
p Value 0.05 0.19
0.94 0.48 0.05 0.10 0.11 ⬍0.005 0.89
Continuous data expressed as mean ⫾ standard deviation; categoric data as number (%).
AP ⫽ anterior posterior; LVEDD ⫽ left ventricular end diastolic diameter; regurgitation; MV ⫽ mitral valve; SD ⫽ standard deviation.
p ⫽ .1). All early postoperative complications are presented in Table 3. Early postoperative echocardiographic results for MR in the closed and open groups, respectively, were as follows: 86% vs 82% had no or trivial MR, 12% vs 16% had mild MR, and 2% vs 2% had mild to moderate MR.
Late Results At follow-up, there were 4 late deaths (2%), all from the open group. Two were valve-related (acute respiratory failure and intracranial hemorrhage), and 2 were nonvalve-related. Kaplan-Meier analysis for late survival at 4 years was 99% ⫾ 1% in the closed group and 93% ⫾ 3% in the open group (p ⫽ .12). Eight patients (3%) required MV reoperations due to recurrent severe MR: 4 (3%) in the closed group and 4 (4%) in the open group (p ⫽ .57). Four reoperations were performed during the first 3 months after the initial operation, and four occurred within the first year. Of these 8 patients, 7 underwent repeat repair of the MV, and the MV was replaced in 1 patient. Freedom from reoperation in all patients was 95% ⫾ 3% at 3 years (94% ⫾ 4% in the closed group, 96% ⫾ 2% in the open group; log rank, p ⫽ .88; Fig 2). Mechanisms of repair failures in the 8 reoperated-on patients were artificial chordal failure in 6 (75%), recurrent prolapse in 2 (50%), retracted posterior leaflet after resection in 1 (12.5%), and ring dehiscence in 1 (12.5%). No operative deaths occurred among the patients who underwent reoperation. NYHA class was similar between the groups at the last follow-up: 88% were in NYHA class I/II and 12% were in class III/IV in the closed group, while 89% were in NYHA class I/II and 11% in class III/IV in the open group (NS). Thromboembolic complications (7 strokes and 26 transient
LVESD ⫽ left ventricular end systolic diameter;
MR ⫽ mitral
ischemic attacks) occurred in 33 patients (13%). Anticoagulation-related hemorrhage occurred in 3 patients (1.1%). Late echocardiography data are presented in Table 4. Mean MR was 1.4 ⫾ 0.9 in the closed group and 1.6 ⫾ 0.9 in the open group (p ⫽ .05). Recurrence of grade 3 to 4 MR occurred in 30 patients (12%), of whom 8 underwent reoperations. Freedom from grade 3 to 4 MR was 91% in the closed group and 84% in the open group (p ⫽ .05). There were no differences between the groups in valve area and gradient across the MV. Of the total 265 late follow-up echocardiographic records, 87 examinations were done in the echocardiography laboratory of our medical center. These 87 examinations were re-reviewed by a single examiner, blinded to the surgical technique, who measured MV anteriorposterior diameter, coaptation length, and annulus to coaptation point. All measurements were done in the same transthoracic echocardiogram examination: 4-chamber apical view (Fig 3). The mean follow-up duration between the 87 patients with coaptation data and the 178 patients without coaptation data was similar, with no statistical differences. A significantly longer line of MV leaflet coaptation was found in the closed (9.1 ⫾ 2.7 mm) group than in the open group (7.1 ⫾ 1.9 mm; p ⬍ 0.01). There were no differences in the anterior-posterior diameter and annulus to coaptation point distance. We further analyzed the coaptation line in the subgroups of isolated posterior pathology (58 patients) and anterior/bileaflet pathology (29 patients), and the coaptation length was significantly longer in the closed group in both subgroups. Causes for late repair failure (grade 3 to 4 MR), were progression of degenerative disease or surgical technique failure. These failures included artificial chordal
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failure, recurrent prolapse, ring dehiscence, and insufficient coaptation. According to univariant analysis, the use of the open annuloplasty ring was the only predictor for late recurrence of grade 3 to 4 MR. Other variables, such as preoperative characteristics and repair techniques (leaflet resection and artificial chordal), did not predict late recurrence of significant MR.
Comment Although MV repair results are superior to MV replacement [3], and repair is considered the procedure of choice for degenerative severe MR disease, the long-term results are still suboptimal. Gillinov and Cosgrove [2] reported 93% freedom from reoperation at 10 years, with a mean follow-up of 4.0 ⫾ 2.9 years. David and colleagues [7] reported 94% freedom from reoperation and 89% freedom from recurrent severe MR at 12 years. Recent publications reveal similar results, with freedom from reoperation and moderate or severe MR exceeding 95% and 77%, respectively [8, 9]. The present study demonstrates comparable results, although length of follow-up was shorter. Predictors for reoperation and moderatesevere MR recurrence are anterior leaflet prolapse, lack of annuloplasty, concomitant procedures, left ventricular dysfunction, advanced age, and higher NYHA [7, 9 –11]. Common valve repair techniques include posterior leaflet resection, sliding repair, chordal transfer, chordal shortening, Alfieri edge-to-edge, and artificial chordal implantation. Valve annuloplasty is an important component of MV repair in almost all MV pathologies. Its overall role is to reduce both the size of the annulus and tension on the sutures, increase leaflet coaptation, and reinforce the annulus to prevent future dilatation, while concurrently providing flexibility and mobility. It is also known that annuloplasty improves valve repair durability [2, 12]. Although various annuloplasty techniques are in use, and good results have been reported with all of them, the optimal choice is still debated. Several studies have examined the effect of annuloplasty type on repair durability and left ventricular function, but no one type has been shown to be superior to another. David and colleagues [13] showed better systolic function in patients with a flexible ring on short-term follow up. Gillinov and Cosgrove [11] reported equivalent midterm results when posterior was compared with closed annuloplasty [11]. Chang and colleagues [14] enrolled 356 patients to a randomized controlled trial and compared a rigid ring with a closed flexible ring, showing similar long-term outcomes between the groups. Annuloplasty type was related neither to early nor late clinical and echocardiographic results. Our study suggests that closed rings may be more advantageous than posterior bands in terms of less recurrent moderate-severe MR. We have used the closed annuloplasty ring more frequently in recent years, based on our observation that closed semi-rigid ring resulted in increased coaptation length and the perception that this could improve repair durability. Coaptation between valve leaflets is one of the key
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points of MV repair, and the importance of coaptation length has also been recognized in regulating MR [15]. Although no reports to date have described the optimal length of coaptation in degenerative MV repair, research has shown that coaptation length may affect repair durability in patients with ischemic MR [16]. It is reasonable to assume that a longer coaptation line could also improve durability and long-term outcome of MV repair in degenerative MV disease. Bax and colleagues [17] demonstrated excellent results of MV annuloplasty and coronary artery bypass grafting with an 8-mm coaptation length in ischemic MV repair. The mean coaptation length in our study was 9 mm in the closed ring group and 7 mm in the open band group. This 2-mm difference may be of significance in terms of late MR recurrence, which was favorable in the closed ring patients. In our study, the length of MV leaflet coaptation was longer in the closed ring group in patients with isolated posterior, isolated anterior, or bileaflet pathology. It is noteworthy that in instances of isolated posterior leaflet prolapse, leaflet resection was less common in the closed group (63%) than in the open group (85%, p ⫽ .07). It is therefore reasonable to conclude that not only closed annuloplasty type but also “less” resection of the posterior leaflet could improve the coaptation surface, as was recently published by others [18, 19]. Our study shows a tendency towards better echocardiographic results using closed semirigid rather than open flexible ring annuloplasty. The lower rate of recurrent MR in the closed group did not translate to better clinical outcomes (NYHA class and reoperation rate), but this could have been due to the short follow-up, which precluded evaluation of the long-term effects of the echocardiographic results on clinical outcome. In accord with the present study, however, significant recurrent MR tends to occur early postoperatively [20], so it is unlikely to assume that the trend we observed in our limited follow-up period would change dramatically in the long-term. It is noteworthy that in the closed ring group, where patients demonstrated a tendency toward better echocardiographic midterm results compared with their open ring counterparts, anterior or bileaflet pathology was more common, a factor that several previous publications have shown is a predictor for early and late repair failure. The closed rigid ring may impair the valve’s natural motion, distort the anterior leaflet, reduce orifice area, increase gradient across the valve, and increase the risk of systolic anterior motion (SAM). In our series the mean gradient was slightly higher in the closed group, with no significant differences in the other variables (Table 4). The risk of SAM after MV repair is caused by anterior displacement of the leaflet coaptation point, secondary to excessive height or redundant tissue of the posterior leaflet [21]. SAM is associated with the use of closed rigid annuloplasty rings but may also occur with open rings or without the use of any ring [22, 23]. We found no differences in SAM prevalence between closed and open annuloplasty. However, we preferred to use the open
ring in those patients who were at higher risk of SAM (small ventricle, tall posterior leaflet).
Study Limitations This was a nonrandomized study with a limited midterm follow-up period, which slightly varied in length between the two groups. Although echocardiographic follow-up was complete, only some of the patients were available for a more detailed analysis, which included coaptation length, anterior-posterior diameter, and annulus to coaptation point.
Conclusions In this retrospective study, we found tendency towards less recurrent significant MR, with longer lengths of leaflet coaptation in the closed ring annuloplasty group. The use of closed rings compared with open bands could therefore improve long-term quality of MV repair. To reach more definite conclusions regarding a relationship between the type of MV annuloplasty, the length of coaptation, and the recurrence of MR, evaluation of a larger patient cohort with more comprehensive early and late echocardiographic follow-up is recommended. We thank Maya First for her expert statistical analysis and Vivienne York for her valuable editorial assistance.
References 1. Avierinos JF, Gersh BJ, Melton LJ 3rd, et al. Natural history of asymptomatic mitral valve prolapse in the community. Circulation 2002;106:1355– 61. 2. Gillinov AM, Cosgrove DM, Blackstone EH, et al. Durability of mitral valve repair for degenerative disease. J Thorac Cardiovasc Surg 1998;116:734 – 43. 3. Mohty D, Orszulak TA, Schaff HV, Avierinos JF, Tajik JA, Enriquez-Sarano M. Very long-term survival and durability of mitral valve repair for mitral valve prolapse. Circulation 2001;104:I1–I7. 4. Suri RM, Schaff HV, Dearani JA, et al. Survival advantage and improved durability of mitral repair for leaflet prolapse subsets in the current era. Ann Thorac Surg 2006;82:819 –26. 5. Enriquez-Sarano M, Orszulak TA, Schaff HV, Abel MD, Tajik AJ, Frye RL. Mitral regurgitation: a new clinical perspective. Mayo Clinic Proceedings 1997;72:1034 – 43. 6. Akins CW, Miller DC, Turina MI, et al. Guidelines for reporting mortality and morbidity after cardiac valve interventions. Ann Thorac Surg 2008;85:1490 –5. 7. David TE, Ivanov J, Armstrong S, Christie D, Rakowski H. A comparison of outcomes of mitral valve repair for degenerative disease with posterior, anterior, and bileaflet prolapse. J Thorac Cardiovasc Surg 2005;130:1242–9.
SPIEGELSTEIN ET AL CLOSED VS OPEN ANNULOPLASTY RING
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8. Miura T, Eishi K, Yamachika S, et al. Mitral valve repair for degenerative disease with leaflet prolapse: to improve longterm outcomes. Gen Thorac Cardiovasc Surg 2009;57:10 –21. 9. Stevens LM, Basmadjian AJ, Bouchard D, et al. Late echocardiographic and clinical outcomes after mitral valve repair for degenerative disease. J Cardiac Surg 2010;25:9 –15. 10. Chenot F, Montant P, Vancraeynest D, et al. Long-term clinical outcome of mitral valve repair in asymptomatic severe mitral regurgitation. Eur J Cardiothorac Surg 2009;36: 539 – 45. 11. Gillinov AM, Cosgrove DM. Mitral valve repair for degenerative disease. J Heart Valve Dis 2002;11(suppl 1):S15–20. 12. Cohn LH, Couper GS, Aranki SF, Rizzo RJ, Kinchla NM, Collins JJ Jr. Long-term results of mitral valve reconstruction for regurgitation of the myxomatous mitral valve. J Thorac Cardiovasc Surg 1994;107:143–50. 13. David TE, Komeda M, Pollick C, Burns RJ. Mitral valve annuloplasty: the effect of the type on left ventricular function. Ann Thorac Surg 1989;47:524 –7. 14. Chang BC, Youn YN, Ha JW, Lim SH, Hong YS, Chung N. Long-term clinical results of mitral valvuloplasty using flexible and rigid rings: a prospective and randomized study. J Thorac Cardiovasc Surg 2007;133:995–1003. 15. Yamauchi T, Taniguchi K, Kuki S, et al. Evaluation of the mitral valve leaflet morphology after mitral valve reconstruction with a concept “coaptation length index.” J Cardiac Surg 2004;19:535– 8. 16. Kuwahara E, Otsuji Y, Iguro Y, et al. Mechanism of recurrent/persistent ischemic/functional mitral regurgitation in the chronic phase after surgical annuloplasty: importance of augmented posterior leaflet tethering. Circulation 2006;114: I529 –34. 17. Bax JJ, Braun J, Somer ST, et al. Restrictive annuloplasty and coronary revascularization in ischemic mitral regurgitation results in reverse left ventricular remodeling. Circulation 2004;110:II103– 8. 18. Perier P, Hohenberger W, Lakew F, Batz G, Urbanski P, Zacher M, Diegeler A. Toward a new paradigm for the reconstruction of posterior leaflet prolapse: midterm results of the “respect rather than resect” approach. Ann Thorac Surg 2008;86:718 –25. 19. Falk V, Seeburger J, Czesla M, et al. How does the use of polytetrafluoroethylene neochordae for posterior mitral valve prolapse (loop technique) compare with leaflet resection? A prospective randomized trial. J Thorac Cardiovasc Surg 2008;136:1205. 20. Meyer MA, von Segesser LK, Hurni M, Stumpe F, Eisa K, Ruchat P. Long-term outcome after mitral valve repair: a risk factor analysis. Eur J Cardiothorac Surg 2007;32:301–7. 21. Lee KS, Stewart WJ, Lever HM, Underwood PL, Cosgrove DM. Mechanism of outflow tract obstruction causing failed mitral valve repair. Anterior displacement of leaflet coaptation. Circulation 1993;88:II24 –9. 22. Kupferschmid JP, Carr T, Connelly GP, Shemin RJ. Systolic anterior motion of the mitral valve after valve repair without an annular ring. Ann Thorac Surg 1994;57:484 – 6. 23. Lopez JA, Schnee M, Gaos CM, Wilansky S. Left ventricular outflow tract obstruction and hemolytic anemia after mitral valve repair with a Duran ring. Ann Thorac Surg 1994;58:876 –7.
INVITED COMMENTARY Spiegelstein and associates [1] have addressed an important question: Should complete rings be used for the repair of mitral regurgitation from degenerative disease? Strong clinical evidence supports the use of closed, rigid or semirigid annuloplasty rings for myopathic (regional ischemic and global cardiomyopathic) disease [2]. Similar findings for degenerative disease have not been reported. © 2010 by The Society of Thoracic Surgeons Published by Elsevier Inc
The present study by Spiegelstein and associates [1] concludes that the use of closed rings is associated with improved leaflet coaptation and freedom from recurrent regurgitation for patients with degenerative disease. A strength of this work is the admirable 98% echocardiographic follow-up; however, there are concerns that transthoracic echo cannot measure coaptation at the level 0003-4975/$36.00 doi:10.1016/j.athoracsur.2010.05.006
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