Early and late results of mitral valve repair in children

Surgery for Congenital Heart Disease

Early and late results of mitral valve repair in children Mitral valve repair m children has the advantage of avoiding mitral valve replacement with its attendant need for anticoagulation and reoperation. Seventy-nine children between the ages of 2 months and 17 years (mean 4.9 years) underwent mitral valve repair between May 1982 and April 1993. There were five patients with mitral stenosis and 74 patients with mitral regurgitation, and 19 children were less than 2 years of age. Patients were divided into anatomic subgroups on the basis of the primary cardiac pathologic condition. Forty-three had severe mitral regurgitation, 21 had moderate mitral regurgitation, and 12 patients with primum atrial-septal defect and 2 patients with univentricular hearts had minimal to moderate mitral regurgitation. Associated cardiac anomalies were present in 68 patients and 85 % of the patients required concomitant intracardiac procedures. The methods of mitral valve repair included annuloplasty in 68 (86 %), repair of cleft leaflet in 41 (52 %), chordal shortening in 9 (11 %), triangular leaflet resection in 8 (10%), splitting of papillary muscles with resection of subvalvular apparatus in 7 (9 % ), and chordal substitution in 1 (1 %). The technique of annuloplasty was modified to allow for annular growth. Follow-up was available from 1 to 10 years (mean 4 ± 2.5 years). There were three early deaths (4 %), all occurring as a result of low output cardiac failure in patients with minimal postoperative mitral regurgitation. Three late deaths (4%) occurred in patients with persistent moderate to severe mitral regurgitation and progressive cardiac failure and eight patients (10%) required either rerepair or replacement of the mitral valve. Actuarial survival was 94% at 1 year, 84% at 2 years, and 82% at 5 years, and actuarial freedom from reoperation was 89% at 8 years. AU patients received postoperative echocardiography with 82 % having minimal to no mitral regurgitation and 98 % of long-term surviving patients being free of symptoms. We conclude that mitral valve repair can be done with low early and late mortality. The need for reoperation is relatively low and valve growth has occurred with the use of a modified annuloplasty. (J THORAC CARDIOVASC SURG 1994;107:1262-71)

Alon S. Aharon (by invitation), Hillel Laks, MD, Davis C. Drinkwater, MD, Reema Chugh, MD (by invitation), Richard N. Gates, MD (by invitation), Peter W. Grant, MD (by invitation), Lester C. Permut, MD (by invitation), Abbas Ardehali, MD (by invitation), and Ehud Rudis, MD (by invitation), Los Angeles, Calif.

From the University of California at Los Angeles School of Medicine, Division of Cardiothoracic Surgery, Los Angeles, Calif. Read at the Seventy-third Annual Meeting of The American Association for Thoracic Surgery, Chicago, Ill., April 25-28, 1993. Address for reprints: Hillel Laks, MD, Professor and Chief, Division of Cardiothoracic Surgery, 10833 Le Conte Ave., Rm. 62-182, Los Angeles, CA 90024-1741. Copyright © 1994 by Mosby-Year Book, Inc. 0022-5223/94 $3.00

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Mitral valve repair in adults is now well established with long-term follow-up confirming its reliability.l > In children, there is a wide spectrum of congenital and acquired lesions and relatively less experience with valve repair.? Mitral valve replacement in children, and particularly in infants, is associated with a high mortality, the need for anticoagulation, and a high rate of reoperation for prosthetic valve replacement with growth.7- 12 Mitral

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valve repair offers the advantages of avoidance of thromboembolism, preservation of chordal function, and potentiallya reduced need for reoperation, Because of the wide spectrum of lesions, multiple techniques of valve repair are required and some of those used in adults require modification. Patients and methods Seventy-nine children between the ages of 2 months and 17 years underwent mitral valve repair at the University of California at Los Angeles (UCLA) Medical Center between May 1982 and April 1993. There were 5 patients with mitral stenosis (MS) and 74 patients with mitral regurgitation (MR). There were 42 boys and 37 girls; the mean age was 4.9 years and 19 children were younger than 2 years of age. Patients were divided into fiveanatomic groups on the basis of the primary cardiac pathologic condition. Group 1 (n = 18) included patients with congenital MS or MR (excluding those with MR and endocardial cushion defects), group 2 (n = 17) included patients with univentricular heart, group 3 (n = 25) included patients with primum atrial septal defect (ASD), group 4 (n = 13) included patients who underwent prior repair of atrioventricular canal (AVe) and had postoperative moderate or severe MR, and group 5 (n = 6) included patients with acquired mitral valve lesions. Children with newly diagnosed complete AVC were excluded (Table I). A functional classification system described by Carpentier and associates" based on the pathologic malformations of the mitral valve was used to categorize the mitral valve lesions. Mitral valve incompetence was classified as occurring in association with normal leaflet motion (type I), prolapsed leaflet motion (type 11), or restricted leaflet motion (type III). MS (type IV) was classified as occurring with either normal leaflet motion or restricted leaflet motion. Mitral valve lesions were assessed by preoperative echocardiography and angiography in all patients. Since 1987 all patients received intraoperative transesophageal echocardiography. In patients with congenital mitral valve pathologic conditions (group I), 15 patients had MR and 3 patients had combined MR and MS. Mitral valve lesions included 10 cases of prolapse of the anterior leaflet, 3 of cleft anterior leaflet, 2 of subvalvular MS, I of supravalvular MS, 1 of prolapsed posterior leaflet, and I of cleft posterior leaflet. Preoperative echocardiographic findings showed 13 patients with severe MR, 3 patients with severe MR and MS, and 2 patients with moderate MR. Methods of mitral valve repair included modified De Vega annuloplasty in 17 patients, glutaraldehyde-preserved pericardial strip annuloplasty in I, triangular resection of the anterior leaflet in 8, shortening of the chords in 6, repair of posterior or anterior leaflet in 5, triangular resection of the posterior leaflet in 2, division of the papillary muscle in 2, resection of supravalvular ring in 1, and chordal replacement in I. Concomitant procedures were closure of ventricular septal defect in 3, tricuspid valve annuloplasty in 2, aortic valve repair in 2, aortic valve replacement in I, and closure of secundum ASD in I. Of the 17 patients with univentricular heart (group 2),12 had single ventricle, 2 had double-inlet left ventricle, 4 had tricuspid atresia, and 4 had pulmonic atresia with intact ventricular septum. Three had associated subaortic obstruction and 2 patients had unbalanced AVC with hypoplastic left ventricle. Mitral

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Table I. Classification ofpatients

Group I. Congenital mitral

n

Mean age in years (range)

18

5.5 (7 mo-I4 yr)

MRgrade

Severe* valve lesions Moderate Minimal 2. Univentricular heart 17 5.6 (I yr-12yr) Severe Moderate Minimal 3. Primum ASD 25 4.4 (I I mo-l O yr) Severe Moderate Minimal 4. Prior repair of AVC 13 2.1 (5 mo-7 yr) Severe Moderate Minimal 5. Acquired mitral 12 (2 yr-17yr) Severet 6 valve lesions Moderate Minimal

n 16 2 0

6 9

2 6 7 12 II

2 0

4 I

0

'Three patients with severe MRjMS.

tFour patients with severe MRjMS.

valve lesions included 13 cases of isolated annular dilatation, 2 of prolapse of the anterior leaflet, and 2 of cleft anterior leaflet. Preoperative Doppler echocardiography showed 6 patients with severe MR, 9 patients with moderate MR, and 2 patients with mild MR. Repair was accomplished by partial De Vega annuloplasty in 17, repair of cleft anterior leaflet in 2, suture of cleft for common atrioventricular (AV) valve in 2 patients, and shortening ofthe chords to the anterior leaflet in I. Both patients with mild MR had isolated annular dilatation. Concomitant procedures included modified Fontan procedure with intraatrial baffle and adjustable ASD in 12, Damus-Stansel-Kaye procedure in 3, repeat modified Fontan procedure in 2, and bidirectional Glenn shunt in 2. Group 3 consisted of 25 patients with primum ASD and cleft anterior mitral leaflet. All patients had closure of the cleft anterior leaflet and 15 patients also underwent partial De Vega annuloplasty. Preoperatively there were 12 patients with minimal MR, 7 patients with moderate MR, and 6 with severe MR in this group. Concomitant lesions necessitating repair included 4 cases of secundum ASD, 2 of residual ASD, 2 of subaortic stenosis, and I of Ebstein's anomaly. Group 4 consisted of 13 patients who had previous repair of AVC and persistent postoperative MR. Eleven patients had severe MR and 2 patients had moderate MR before operation. Mitral valve lesions included 9 cases of cleft anterior leaflet, 2 of prolapse of the anterior leaflet, I of restricted leaflet motion, and 1 of subvalvular MS. Methods of repair included modified De Vega annuloplasty in 12, repair of cleft anterior leaflet in 9, shortening of the chords in 2, and splitting of the papillary muscle and commissurotomy in 1 patient. Lesions necessitating concomitant repair included tricuspid valve regurgitation in 4 patients, residual ventricular septal defect in 2, subaortic stenosis in 2, and aortic valve regurgitation in I. Group 5 consisted of six patients with acquired MR or MS. There were three patients with rheumatic heart disease, two with subacute bacterial endocarditis, and one with balloon tear of the anterior leaflet of the mitral valve during attempted aor-

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Fig. 1. Technique of mod ified De Vega annuloplasty, which is done in two pa rts to a llow for a nnular growth.

Table II. Functional classification of M V lesions and type of repair Type a/ lesion

Annular dilatation

n

Technique 0/ repair

n

68

Modified De Vega annuloplasty Glutaraldehyde-preserved pericardial strip annuloplasty Carpentier-Edwards ring Primary repair Chordal shortening Triangular resection Chordal substitution Triangular resection Chordal shortening Splitting of papillary muscles with resection of subvalvular apparatus Closure of cleft and repair of leaflets

65

Cleft anterior leaflet Prolapsed anterior leaflet

39 16

Prolapsed posterior leaflet

5

Restricted leaflet motion

7

Common AV valve

2

2

39 9 6 I 3

2 7

2

tic balloon valvuloplasty . Mitral va lve lesions included prolapse of the a nterior leaflet in 2 pat ients, prol aps e of the posterior leaflet in 2, cleft anterior leaflet in I, isolated annular dila tation in I , subva lvular MS in I , and torn a nterior leaflet in I . Four patient s had severe MR, I had moderate MR, and I had severe MS befor e operation. Methods of mitral valve repair included mod ified De Vega annuloplasty in 4 pat ients, repair of cleft a nterior leaflet in 2, trian gular resect ion of the posterior or a nterior leaflet in 2, glutaraldehyde-p reserved pericardial strip a nn uloplasty in 1, Carpentier-Edwards ring annuloplasty in I,

Fig. 2. Technique of glutaraldehyde-preserved pericardial strip a nnuloplasty. Two stri ps of glutara ldehyde-preserved pericardium a re used to reinfor ce modified De Vega a nnuloplast y, a lso allo wing for annular growth . repair of defect in anterior leaflet in I, division of the papillar y mu scle with commissurotom y in I, and tr an sposition of chords in I. Concomitant procedures included aort ic valve repla cement in 2, ao rtic valve repair in I, and tric uspid va lve annuloplasty in I.

Surgical techniques Conduct of bypass and myocardial protection. Surgical

man agement since 1987 included placement of inst ru ments for intrao pera tive transesophag eal echoca rdiogra phy in a ll patients. Cardiopulmonary bypass was instituted with bicaval a nd ao rtic cannulation a nd systemic hypothermia to 24 0 C. Th e method of m yocardial protection was interm itt ent cold blood ca rdioplegia given in an a ntegrade and retrograde fashion with monitoring of pressure and flow rate. Controlled reperfusion with substrate-enhanced warm blood cardioplegic solution followed by regular blood was also used . The mitral valve was exposed via the right atrium and th e atrial septum or directly via the left atrium depending on the size of the left atrium and on associated procedures. Valve function was assessed by injection of cold S1. Thomas' Hospital solution into the left ventricle with a syrin ge before closure of the left a trium a nd by transesophageal echoca rdiogra phy after term ination of ca rdiopulmona ry bypass. S pecific considerations (Ta ble II ) A NNULAR DILATATION. Annular dilat ati on was present in 68 (86 %) of the pat ients with 66 pat ients (84%) having other mitral valve lesions necessitating concom itant reconstruction . Isolated annula r dilatation was present in 13 patient s (16 %). Methods of annular repair included mod ified De Vega annuloplasty in 65 pa tients (Fig. I ), gluta ra lde hyde-preserved pericardia! strip in 2 pati ent s (Fig. 2), and Carpent ier-Ed wards ring in I patient. T o allow for growth the a nnuloplasty was done in two or mor e sections. R EPAIR OF CLE Ff IN THE ANTERIOR LEAFLET. Cleft a nterio r leaflet was found in 39 patient s (49%). There were 25 patients with primum ASD, 9 patients with prior re pair of A VC, 3 pat ients with congenital mitral va lve lesions, a nd 2 pat ients with

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Fig. 3. Technique of primary repair of cleft anterior leaflet. Modified De Vega annuloplasty is also shown.

Fig. 4. Plication of chordas. Technique of chordal shortening for prolapsed anterior leaflet is illustrated. Pericardial pledget-supported Te vdek suture is used to plicate elongated chords to anterior papillary muscle . univentricular heart who had repair of cleft anterior leaflet. Closure of the cleft of the anterior leaflet was done with interrupted 5-0 Tevdek sutures (Deknatel, Inc., Fall River, Mass .) placed on the edge of the leaflet, with care taken not to incorporate excessive valve tissue (Fig. 3). PROLAPSE OFTHE ANTERIOR LEAFLET. Prolapse of the anterior leaflet secondary to elongation of the chords or papillary muscles occurred in 15 patients (I 9%). Prolapse of the anterior leaflet secondary to elongation of the chordae was corrected by plication of the chords to the anterior papillary muscle with pericardial pledget-supported Tevdek sutures in nine patients (Fig. 4), triangular resection of the anterior leaflet in six patients (Fig. 5), and chordal substitution with Tevdek suture in one patient. In view of the high rate of regurgitation after triangular resection of the anterior leaflet. we now prefer chordal support of the flail segment rather than resection . PROLAPSE OFTHE POSTERIOR LEAFLET. Prolapse of the posterior leaflet was present in five patients (6%). Techniques of posterior leaflet repair included triangular resection of the leaflet in three patients and shortening of chords in two patients. RESTRICTED LEAFLET MOTION. Restricted leaflet motion was found in three patients (4%). Restricted leaflet motion was treated by resection of secondary chordae and splitting of papillary muscles in three patients. REGURGITATION THROUGH THE CENTRAL PORTION OF THE COMMON AV VALVE. Regurgitation through the central portion

of the common AV valve was present in two patients with complete A VC and hypopla stic left ventricle. These valves were successfully repaired by supporting the central portion of the valve by closure of the cleft and suture of the adjacent central portion of the leaflets (Fig. 6) . Follow-up. Follow-up was available for 97% of the patients. - The mean period of follow-up was 4 ± 2.5 years (range I to 10 years) . Data were collected from outpatient medical record s from our institution and from referring physicians. All patients or their parents were interviewed to determine exercise tolerance and confirm the accuracy of medical records . Statistical methods. The early and late mortality and the rate of reoperation were analyzed bivariately for age, type of intracardiac pathologic condition, concomitant procedures, preoperative degree of MR, a nd technique of repair (annuloplasty, anterior leaflet, posterior leaflet, shortening of chords, and suture of cleft valve). A bivariate analysis of the impact of annuloplasty with anterior leaflet repair versus annuloplasty with posterior repair, with age and severity ofMR held constant as controls, was done by logistic regression . Statistical analysis was done by the UCLA Medical Center Biostatistics group.

Results Mortality. Early death was defined as any death occurring within 30 days of operation or any in-hospital

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Fig. 5. Technique of triangular resection of anterior leaflet.

Fig. 6. Common AV valve repair. Regurgitation through central position of AV valve was repaired by supporting central portion of common AV valve by closure of cleft and suture of adjacent central portion of leaflets.

death. Three early deaths (4%) occurred, all secondary to low output cardiac failure in patients whose valves were competent after repair as determined by postoperative echocardiography. The first was in a 12-year-old patient with univentricular heart and pulmonic stenosis who underwent a modified Fontan procedure and mitral valve repair. After the procedure there was minimal MR. This patient died on postoperative day 13 of progressive ventricular failure. The second was in an infant who underwent repair of complete A VC at 6 months of age and required subsequent mitral and tricuspid valve repair at 8 months of age. This patient died on postoperative day 16 of progressive ventricular failure despite a competent mitral valve. The third early death occurred in a 4.5year-old patient with congenital MR who died on the first postoperative day after concomitant aortic valve replace-

ment, tricuspid valve annuloplasty, and mitral valve repair. This patient also had a competent mitral valve after operation. Bivariate statistical analysis identified no risk factors for early death. Late death was defined as any out-of-hospital death occurring after postoperative day 30. Three late deaths (4%) occurred in patients with persistent moderate to severe MR and progressive cardiac failure. Two late deaths occurred in patients with congenital mitral valve lesions and one in a patient with univentricular heart. The first death occurred 9 months after operation in a 7-month-old patient who underwent mitral annuloplasty and shortening of the chords to the anterior leaflet of the mitral valve with concomitant pulmonary valvotomy and atrial septectomy. The second occurred in a 7-month-old patient with severe pulmonary hypertension who underwent mitral annuloplasty, triangular resection of the anterior leaflet, and shortening of the chords and who required mitral valve replacement on postoperative day 7 for flail anterior leaflet. Death occurred 20 months after mitral valve replacement secondary to persistent congestive heart failure. The last late death occurred 20 months after operation in a l-year-old patient with univentricular heart and a prior bidirectional Glenn shunt who died after mitral annuloplasty and closure of cleft anterior mitral leaflet. Actuarial survival was 94% at I year, 84% at 2 years, and 82% at 5 years in children undergoing mitral valve repair (Fig. 7). The actuarial survival in children undergoing mitral valve replacement (n = 24) at UCLA between May 1982 and April 1993 is also shown in Fig. 7 for comparison. No risk factors were identified for late death in children undergoing mitral valve repair. Reoperation. Reoperation was defined as the necessity of either replacement or rerepair of the mitral valve. Reoperation was done in eight patients (10%). Seven patients required mitral valve replacement, two with con-

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100 ........... ........ _

90·

_..

......................._ _

_

_

_

_

--_

.

80·

70 - - - - - - - - _ . _ - - - - - - - - - - - - - - --------

60 50

Mitral Valve Repair Mitral Valve Replacement ------------------

o

3 6

9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60 63 66 69 72

Months

Fig. 7. Actuarial survival of children undergoing mitral valve repair (dotted line) as opposed to replacement (solid line).

100 --.---90 -

C Q)

80

~

Q)

a.. 70 60 50

Mitral Valve Repair Mitral Valve Replacement

o

3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60 63 66 69 72

Months

Fig. 8. Improved actuarial freedom from reoperation in children with mitral valve repair (dotted line) as opposed to replacement (solid line).

genital mitral valve lesions,two with prior repair of Aye, two with acquired mitral lesions, and one with univentricular heart. Rerepair of the mitral valvewas done in one patient with univentricular heart. The actuarial freedom from reoperation was 97% after 2 years, 92% after 4 years, and 83% at 8 years (Fig. 8). All patients in the group with congenital mitral valve lesions who required mitral valve replacement for persistent severe MR underwent triangular resection of the anterior leaflet. Bivariate statistical analysis revealed a trend toward mitral valve replacement in patients with anterior leaflet prolapse and subsequent triangular resection of the anterior leaflet. However, this trend did not reach statistical significance. No other risk factors were identified for rerepair or replacement.

Complications. Major complications of mitral valve repair were defined as thromboembolic or hemorrhagic events. There was one thromboembolic event (I %) despite adequate anticoagulation. This resulted in transient right-sided paralysis in a 17-year-old male patient after combined mitral repair and aortic valve replacement. There were no major hemorrhagic complications. Durability. Durability and quality of repair were determined by MR seen on follow-up echocardiography and functional classification. Long-term follow-up of surviving patients revealed 65 patients (82%) with none to minimal MR, 7 (9%) patients with moderate MR, and 7 (9%) patients with severe MR. All long-term surviving patients were either free of symptoms or had minimal to mild exercise intolerance. The actuarial freedom from

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Aharon et al.

valve failure (defined as need for mitral valve replacement' or rerepair, valve-related death, or persistent moderate or severe postoperative MR seen on echocardiography) was 96% at 2 years, 91% at 4 years, and 79% at 8 years. Bivariate statistical analysis did not identify any factors predictive of postoperative durability, quality of repair, or freedom from valve failure. Discussion Numerous studies have reported on congenital and acquired MR in children.P'" Recent studies have stressed the importance of classifying MR or MS on the basis of the types of lesions found at operation.? This functional classification system first developed by Carpentier and associates? allows the surgeon to place complex mitral valve lesions into four basic groups. Group I includes valves with normal leaflet motion and either isolated annular dilatation or cleft leaflet. Group II includes' valves with prolapse of the anterior or posterior leaflet, or both, and group III includes valves with restricted leaflet motion. Group IV generally refers to lesions that cause MS. Effective surgical repair of the incompetent or stenotic mitral valve may only be achieved if each specific lesion is appropriately corrected. Mitral valve disease may be surgically treated by mechanical or bioprosthetic valve replacement or by valvular reconstruction. The early mortality associated with mitral valve replacement in infants and young children has been relatively high with low output cardiac failure as a major contributing factor to early death.f 16-18 Recent reports of mitral valve replacement in older children have been encouraging, with decreased morbidity and early and late mortality. 19. 20 In our 10-year experience of mitral valve replacement in children, the early mortality rate was 21% (5/24), the late mortality rate was 5% (1/19), and 25% (6/24) of the patients required rereplacement of the mitral valve. Early mortality has been especially high in infants undergoing mitral valve replacement. Kadoba and colleagues? from Children's Hospital in Boston reported 9 early deaths in 21 patients (43%) who underwent mitral valve replacement with mechanicalor porcine bioprostheses within the first year of life. The University of Toronto has also had a high early mortality in infants receiving mitral valve replacement for congenitally insufficient mitral valves.l? Mitral valve replacement with the use of bioprosthetic valves has not improved early survival as compared with the use of mechanical valves in infants." Further, bioprosthetic valves in children have an accelerated rate of tissue degeneration as reported by Geha, Kutsche, Nudelman, and their associates. 21- 23 In general, factors contributing

The Journal of Thoracic and Cardiovascular Surgery May 1994

to the high rate of failure of mitral valve replacement include the continued growth of the child, tissue overgrowth of the replaced valve causing stenosis, and the early calcific degeneration of bioprosthetic valves, reported to be 9% per patient-year by Williams and associates.l" In our experience, 85% of all insufficient and stenotic mitral valves were amenable to repair. The three early deaths (4%) in our series occurred in patients with compromised preoperative ventricular function, complex intracardiac lesions, and minimal MR. Age was not a statistically significant risk factor for early mortality. Late mortality has also been high in infants and young children undergoing mitral valve replacement with mechanical and bioprosthetic valves. The 10-year survival was reported as 76% after mitral valve replacement with the Starr-Edwards valve prosthesis.P and a 5-year survival of 53% was reported by Borkon and colleagues/" after mitral valve replacement with the St. Jude Medical valve. Boston Children's Hospital reported an actuarial survival of 52% at 1 year and 43% at 5 years after mechanical valve replacement or implantation of a porcine bioprosthesis in infants." In contrast, late death after mitral valve reconstruction has been reported to be between 4% and 8%.6, 13, 14 In our series there were three late deaths (4%) that occurred 9, 20, and 20 months after operation in patients with severe persistent MR. All three patients had complex congenital heart disease necessitating concomitant repair. Actuarial survival in our study was 94% at 8 years (Fig. 7). Bivariate analysis revealed no risk factors for late death. The need for reoperation after mitral valve replacement with either mechanical or bioprosthetic valves has been high. 22, 27 Williams and associates/" reported a 48% need for reoperation after 5 years in children who received bioprosthetic valves. Mitral valve repair can be done with a low need for reoperation as confirmed by Carpentier and colleagues," who reported an actuarial risk of reoperation of 13.4% at 5 years and 21% at 10 years. Okita and colleagues':' reported an actuarial freedom from reoperation of 89% at 10 years, and Kirklin'> reported a 75% rate of freedom from reoperation at 10 years. In our study, eight patients (10%) required reoperation after mitral valve repair for progressive severe MR. Seven patients required mitral valve replacement and one patient underwent rerepair of the mitral valve. Type of intracardiac pathologic condition, concomitant procedures, age, preoperative MR, previous history of subacute bacterial endocarditis or rheumatic heart disease, and prior cardiac procedures were not statistically significant risk factors for failure of repair. The actuarial freedom from reoperation in our study was 97% after 2 years and 83% at 8

The Journal of Thoracic and Cardiovascular Surgery Volume 107, Number 5

years (Fig. 8). Bivariate statistical analysis revealed no risk factors for reoperation. However, we did identify a trend toward need for reoperation in patients with prolapse of the anterior leaflet who underwent triangular resection of the anterior leaflet. The low rate of thromboembolic complications with mitral valve repair compares favorably with results reported after mechanical or bioprosthetic mitral valve replacement by Carpentier and associates." In our series, one patient had transient right-sided paralysis despite adequate anticoagulation after mitral valve repair and aortic valve replacement 18 months after operation. Repair of the mitral valve offers the advantage of avoiding the need for lifelong anticoagulation in children. Functional results after repair ofthe mitral valve in this study have been excellent. All patients received postoperative echocardiography with 82% having minimal to no MR and 9% having moderate MR. Ninety-eight percent of long-term surviving patients were free of symptoms or had minimal to mild exercise intolerance. Bivariate statistical analysis did not reveal age less than 2 years (n = 21) to be a significant risk factor for early mortality, late mortality, or need for reoperation in children who underwent mitral valve repair. There was no early mortality in children younger than 2 years. The three late deaths (14%) in patients younger than 2 years occurred in children with poor ventricular function and minimal or moderate postoperative MR. Two children (10%) required mitral valve replacement for persistent severe postoperative MR 7 days and 8 months, respectively, after mitral valve repair. We have continued to modify our surgical technique to optimize postoperative results. Our experience, as well as that of Carpentier and associates" and others, has found the results of triangular resection of the anterior leaflet to be unsatisfactory. We presently treat prolapse of the anterior leaflet with the technique of chordal shortening by suturing the elongated chords to the papillary muscle with a glutaraldehyde-treated pericardial strip. We have also begun to treat annular dilatation with a glutaraldehyde-preserved pericardial strip. This technique consists of using pericardium in two parts to allow for valve growth and obviates the need for anticoagulation. Annuloplasty is done in all patients with annular dilatation irrespective of mitral valve disease. We have found that annuloplasty alone for the common A V valve in the univentricular heart is not adequate and that support of the central portion of the valve by suture of the cleft and of the central components of the right-sided portion of the valve (see Fig. 6) results in a competent valve. Further, we believe that suture of the cleft should be done in all patients with

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this defect. In patients with AVC defects and systemic ventricular outflow obstruction (n = 7) redundant valve and fibrous tissue were resected at the time of AV valve repair. Successful relief of systemic ventricular outflow obstruction was confirmed by transesophageal echocardiography. Conclusion. Mitral valve repair in children is a safe procedure with low early and late mortality and has the advantage of avoiding many of the described complications ofprosthetic valve replacement. Good results require careful functional assessment of the valve and the use of multiple techniques to address all components ofthe valve lesion. When possible, mitral valve repair is the procedure of choice for correction of both MR and MS in children. REFERENCES I. Reed GE, Pooley RW, Moggio RA. Durability of measured mitral annuloplasty: seventeen-yearstudy. J THORAC CARDIOVASC SURG 1980;79:321-5. 2. Spencer FC, ColvinSB, Culliford AT, Isom OW. Experiences with the Carpentier techniques for mitral valve reconstruction in 103 patients (1980-1985). J THORAC CARDIOVASC SURG 1985;90:341-50. 3. Galloway AC, Colvin SB, Bauman FG, et al. Long-term resultsof mitral valvereconstruction with Carpentier techniquesin 148patients with mitral insufficiency. Circulation I988;78(Suppl):197-1 05. 4. Carpentier A, Chauvaud S, Fabiani J-N, et al. Reconstructive surgery of mitral valveincompetence. J THORAC CARDIOVASC SURG 1980;79:338-48. 5. Duran CG, Pomar JL, Revuelta JM, et al. Conservative operation for mitral insufficiency: critical analysis supported by postoperative hemodynamic studies of 72 patients. J THORAC CARDIOVASC SURG 1980;79:326-37. .6. Carpentier A, Branchini B, Cour JC, et al. Congenital malformations of the mitral valve in children: pathology and surgical treatment. J THORAC CARDIOVASC SURG 1976;72:854-66. 7. Sand ME, Naftel DC, Blackstone EH, Kirklin JW, Karp RB. A comparison of repair and replacement for mitral valve incompetence. J THORAC CARDIOVASC SURG 1987; 94:208-19. 8. Perier P, DelocheA, Chauvaud S, et al. Comparative evaluation of mitral valve repair and replacement with Starr, Bjork and porcine valve prostheses. Circulation 1984; 70(Suppl):l187-92. 9. Kadoba K, Jonas RA, Mayer JE, Castaneda AR. Mitral valvereplacement in the first year of life. J THORAC CARDlOVASC SURG 1990;100:762-8. 10. Schachner H, Salomon J, Levinsky L. Prosthetic valve replacement in infants and children. J THORAC CARDlOVASC SURG 1984;25:537-44. II. Schaff HV, Danielson GK, Di Donota RM, et al. Late

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results after Starr-Edwards valve replacement in children. 1 THORAC CARDIOVASC SURG 1984;88:583-9. 12. Bradley LM, Midgley FM, Watson DC, et al. Anticoagulation therapy in children with mechanical prosthetic cardiac valves. Am 1 Cardiol 1985;56:533-5. 13. Okita Y, Miki S, Kusuhara K, et al. Early and late results of reconstructive operation for congenital mitral regurgitation in pediatric age group. 1 THORAC CARDIOVASC SURG 1988;96:294-8. 14. Kahn DR, Stern AM, Sigmann 1M, Kirsh MM, Lennox S, Sloan H. Long-term results of valvuloplasty for mitral insufficiency in children. 1 THORAC CARDIOVASC SURG 1967;53:1-6. 15. Kirklin lW. Congenital mitral valve disease. In: Kirklin lW, Barrett-Boyes BG, eds. Cardiac surgery. New York: John Wiley, 1986:1091-106. 16. Sade RM, Ballenger IF, Hohn AR, Arrants lE, Riopel DA, Taylor AB. Cardiac valve replacement in children: comparison of tissue with mechanical prostheses. 1 THORAC CARDIOVASC SURG 1979;78:123-7. . 17. Williams WG, Pollock lC, Geiss OM, Trusler GA, Fowler RS. Experience with aortic and mitral valve replacement in children. 1 THORAC CARDIOVASC SURG 1981;81:32633. 18. Davachi F, Moller lH, Edwards lE. Diseases of the mitral valve in infancy. Circulation 1971;43:565-79. 19. Attie F, Kuri 1, Zanoniani C, et al. Mitral valve replacement in children with rheumatic heart disease. Circulation 1981;64:812-7. 20. Attie F, Lopez-Soriano F, Ovseyevitz 1, et al. Late results of mitral valve replacement with the Bjork-Shiley prosthesis in children under 16 years of age. 1 THORAC CARDIOVASC SURG 1986;91:754-8. 21. Geha AS, Laks H, Stansel HC Jr, et al. Late failure of porcine valve heterografts in children. 1 THORAC CARDIOVASC SURG 1979;78:351-64. 22. Kutsche LM, Oyer P, Shumway N, Baum D. An important complication of Hancock mitral valve replacement in children. Circulation I 979;60(Suppl):I98-1 03. 23. Nudelman I, Schachner A, Levy Ml. Repeat mitral valve replacement in the growing child with congenital mitral valve disease. 1 THORAC CARDIOVASC SURG 1980;79:7659. 24. Williams DB, Danielson GK, McGoon DC, Puga F1, Mair DO, Edward WD. Porcine heterograft valve replacement in children. 1 THORAC CARDIOVASC SURG 1982;84:44650. 25. SchaffH, Danielson GK, Di Donato RM, Puga F, Mair 0, McGoon D. Late results after Starr-Edwards valve replacement in children: pathology and surgical treatment. 1 THORAC CARDIOVASC SURG 1984;88:583-9. 26. Borkon AM, Soule L, Reitz BA, Gott VL, Gardner TJ. Five-year follow-up after valve replacement in children. 1 THORAC CARDIOVASC SURG 1986;74:II 0-5. 27. Friedman S, Edmunds LH Jr, Cuaso Cc. Long term mitral valve replacement in young children: influence of somatic

growth on prosthetic valve adequacy. Circulation 1978; 57:981-6.

Discussion Dr. Sylvain Chauvaud (Paris, France). At Hopital Broussais with Professor Carpentier, we have an experience of more than 150 cases of valve reconstruction in children younger than 12 years of age. Among them, 98 patients had a congenital anomaly responsible for valve insufficiency. Like the authors, we have used the entire spectrum of reconstructive techniques. At the beginning of our experience, we tried to avoid the use of a prosthetic ring to preserve annular growth. However, secondary dilatation of the anulus and subsequent insufficiency led to reoperation in most of the patients in whom an annuloplasty was not used. We concluded that an annuloplasty is mandatory in almost all cases of valvular insufficiency secondary to congenital malformation. Our current policy to minimize the problem of annular growth is to enlarge either the mural or the anterior leaflet, or both, so that a larger ring can be used. We think that this technique is superior to the use of pericardial annuloplasty, which has not given us good long-term results. We would like to know what, since your technique of using pericardium has been introduced, has been the longest follow-up, and have you seen any particular drawback or advantage associated with the technique? Dr. John J. Lamberti, Jr. (San Diego, Calif). I would like to point out that the title of this excellent paper should really be "Early and Late Results of Systemic Atrioventricular Valve Repair." The authors demonstrate the great utility of modern concepts of valve repair in children. However, there is no mention of patients with stenosis. In addition, I think the reader would benefit from some information telling us how the authors decide when to repair versus replace. For example, we would like to know how many valve replacements were done during the same period of time and whether the authors went into the operating room with a preconceived notion as to which patient was going to receive repair. I have one question. In our experience, which extends to about 45 cases of repair, we have seen significant hemolysis in two of the most creative repairs. I wonder if the authors have seen any hemolysis after repair and how it was managed. Mr. Jaroslav F. Stark (London, England). I have two questions. How many valves did you have to replace in the group with congenital mitral valve lesions during the first procedure, that is, in how many cases was it impossible to repair the valve? The second question relates to the techniques the authors have described. In how many patients younger than 6 months of age was it possible to do chordal shortening and evaluation of subvalvular apparatus? I personally find this difficult in small babies younger than 6 to 12 months. Dr. Serafin Y. DeLeon (Maywood, Ill.). In the patients who had previous repair of AVC, what was the cause of MR? Could it be that a single patch technique was done, producing a shortened mitral valve? It may be just a matter of detaching the anterior mitral leaflet from the patch and lengthening it. Dr. Aharon. I would like to thank Dr. Chauvaud for his kind comments. We have been using pericardial strip annuloplasty since about 1988 in adults and since 1989 in children. Our longest follow-up in a child is approximately 2 years. The strip is sutured into position with a double running suture and can

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therefore be easily and rapidly inserted. The strips do not necessitate the use of anticoagulation and are presumably more resistant to infection than a prosthetic ring. We see no drawbacks in their use. Dr. Lamberti, we had seven patients with MS, each of whom had rather complex subvalvular MS. Four had subvalvular MS and three had a supravalvular ring. In our mitral valve replacement series in children, approximately 24% had congenital mitral valve disease. The third question was related to the decision to repair rather than replace. The transesophageal echocardiogram is helpful in assessing the adequacy of the valve tissue and subvalvular apparatus for a repair, but the final decision is made intraoperatively. We have not seen any cases of hemolysis with our techniques of repair to date in children. Mr. Stark, we have had poor results with a triangular

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resection for a flail central portion of the anterior leaflet, which has also been reported by Professor Carpentier. We therefore now prefer either cordal shortening or the use of artificial polytetrafluoroethylene cords to suspend the flail portion of the anterior leaflet. We have had six children who underwent cordal shortening, one of whom was less than 6 months of age. The last question was from Dr. DeLeon regarding the cause of mitral insufficiency after complete AVC repair. In the majority of cases the lower part of the sutured cleft in the anterior leaflet had reopened. In addition, the anulus was dilated in most patients. In a small number, the annuloplasty had previously been done with Prolene suture (Ethicon, Inc., Somerville, N.J.) which unraveled with stretching of the anulus. In these cases the cleft was resutured and an annuloplasty was done with a pericardial strip.