Ann Thorac Surg 2005;79:1500-1504
© 2005 The Society of Thoracic Surgeons
Original articles: Cardiovascular
Anterior Leaflet Repair With Patch Augmentation for Mitral Regurgitation
Matthew A. Romano, MD,
Himanshu J. Patel, MD,
Francis D. Pagani, MD, PhD,
Righard L. Prager, MD,
G. Michael Deeb, MD,
Steven F. Bolling, MD*
Section of Cardiac Surgery, University of Michigan, Ann Arbor, Michigan
Accepted for publication August 23, 2004.
* Address reprint requests to Dr Bolling, 2120 Taubman Center, Box 0348, 1500 E. Medical Center Dr., Ann Arbor, MI 48109–0348; (E-mail: sbolling{at}umich.edu).
Presented at the Fiftieth Annual Meeting of the Southern Thoracic Surgical Association, Bonita Springs, FL, Nov 13–15, 2003.
 |
Abstract
|
|---|
BACKGROUND: Anterior leaflet repair continues to pose significant operative challenges, particularly in patients with retracted or "short" anterior leaflets, due to rheumatic or radiation induced mitral valve disease. This often results in abandonment of repair in favor of mitral valve replacement, requiring anticoagulation and altering left ventricular (LV) function and geometry. This study examines our experience of anterior leaflet repair with patch augmentation.
METHODS: Forty-two patients underwent mitral valve repair for a shortened anterior leaflet from 1994 to 2003. Twenty-two patients with a mean age of 53 ± 6 years had radiation valvulitis (XR) whereas 20 patients, age 28 ± 7 years had rheumatic heart disease (RHD). Those patients with XR had a mean New York Heart Association (NYHA) class of 3.2 ± 0.4 and an angina score of 2.1 ± 0.6 compared with a NYHA class 3.8 ± 0.2 and no angina in RHD patients. All patients presented with severe MR. Anterior leaflet augmentation with a gluteraldehyde-treated, autologous pericardial patch and complete annuloplasty ring was used in all patients. Additionally, extensive subvalvar debridement was performed in RHD patients. Twelve XR patients underwent concomitant CABG with a mean of 2.4 ± 0.8 grafts/patient. Additional surgical procedures included tricuspid valve repair, anterior septal defect, and aortic valve replacement. Mean follow-up was 39 ± 10 months for XR patients and 12 ± 25 months for RHD patients.
RESULTS: There were two late deaths in XR patients from underlying malignancies and no deaths in RHD patients. Two RHD patients required reoperation for recurrent mitral regurgitation at 3 and 20 months. All patients demonstrated clinical improvements (NYHA I-II) following repair. No mitral stenosis was induced.
CONCLUSIONS: Despite anterior leaflet shortening from XR or rheumatic alterations, opportunity still exists for gratifying mitral valve repair. By utilizing anterior leaflet patch augmentation, concomitantly with ring annuloplasty, anticoagulation is avoided, LV geometry is preserved, and follow-up reveals excellent functional improvement.
|
Introduction
|
|---|
Mitral valve dysfunction is a well-known complication in long-term survivors of mediastinal irradiation [1–3]. The postradiation leaflet changes include fibrosis, thickening, and shortening with or without calcification [4, 5]. Similar alterations may also be seen in rheumatic heart disease (RHD), due to the chronic fibrosis and scarring. Consequently, these changes, although from different modalities, may result in a short, "shrunken" anterior leaflet. This short anterior leaflet does not provide for adequate coaptation and results in mitral regurgitation and the subsequent development of heart failure. Historically, mitral valve replacement has been used to surgically manage these patients. Today the benefits of mitral valve (MV) reconstruction for operative correction of mitral regurgitation (MR) are well established. These benefits include low perioperative mortality, preservation of left ventricular function, avoidance of long-term anticoagulation therapy, decreased thromboembolic complications, a low risk of native valve endocarditis, excellent long-term freedom from reoperation, and improved survival as compared to patients undergoing valvular replacement. However, those patients with radiation or rheumatic changes, who have a fibrotic and retracted anterior leaflet, pose significant operative challenges. Frequently, in this situation due to technical problems and concerns of long-term results, repair has been abandoned in favor of replacement. In this study we describe our experience of anterior leaflet repair with patch augmentation to surgically manage shortened mitral valve anterior leaflets in patients with radiation valvular disease and RHD.
|
Patients and Methods
|
|---|
The records of 42 consecutive patients who underwent mitral valve repair for a shortened anterior leaflet from 1994 to 2003 were reviewed. Twenty-two patients had radiation valvulitis (XR) from previous mediastinal irradiation treatment for a neoplasm. The primary neoplasms requiring radiation were breast cancer, lymphoma, and germ cell tumors (Table 1). The remaining 20 patients had RHD. For this study the operative reports, clinical histories, echocardiograms, electrocardiograms, and cardiac catheterization data were reviewed. Follow-up data were obtained from current clinical records, reports from primary physicians, and laboratory data (electrocardiograms and echocardiograms).
The preoperative demographic data of patients in this study are listed in Table 2. The mean age of the XR was 53 ± 6 years, and 28 ± 7 years in the RHD patients. The mean New York Heart Association (NYHA) functional class for XR and RHD patients was 3.2 ± 0.4 and 3.8 ± 0.2, respectively. The XR cohort had an angina score of 2.1 ± 6 while there was no angina in rheumatic patients. All patients presented with severe mitral regurgitation.
The indications for mediastinal radiation therapy were breast cancer (n = 11), lymphoma (n = 8), and seminoma (n = 3). The most recent increase has been seen in patients surviving treatment for Hodgkin's disease, and this is expected to continue to increase. The mean interval between irradiation and valvular heart operation was 17 ± 12 years.
The concept of this repair with anterior patch augmentation is to lengthen the severely shortened and retracted anterior leaflet to reestablish coaptation (Fig 1). The operative procedure was done by sternotomy. An autologous piece of pericardium was harvested immediately after median sternotomy and bathed in 3% gluteraldehyde for 7 minutes. Following patch harvest, patients were placed on standard cardiopulmonary bypass with bicaval cannulation. Standard blood cardioplegic arrest was initiated with antegrade flow in all patients. Retrograde cardioplegia was used as indicated. A standard right-sided left atriotomy was made parallel to the interatrial groove and extended and wrapping inferiorly and superiorly in the direction of the left superior and inferior pulmonary veins, to facilitate exposure. A self-retaining retractor was placed. The valve was inspected and a curvilinear incision was made in the anterior leaflet parallel to the anterior annulus, from trigone to trigone, leaving 1 to 2 mm of leaflet tissue. This caused the anterior leaflet to "fall" forward and into the ventricle. The autologous patch was then generously fashioned to the size of the ring that was selected to restore the zone of coaptation between the anterior and posterior leaflets. Specifically, the width of the patch was cut to be at least as wide as the trigone to trigone distance. Once appropriately sized, the patch was sewn into the deficit of the anterior leaflet with two running 4-0 or 5-0 Prolene sutures (Fig 2). A complete annuloplasty ring was used in all patients. The annuloplasty ring size was determined by the trigone to trigone distance as well. Extensive subvalvar debridement was performed in RHD patients. The completed repair restored the intraventricular zone of coaptation (Fig 3). This was confirmed at the time of repair by filling the LV with saline through a bulb syringe and visually inspecting the leaflets. Additionally, transesophageal echocardiography was also used to assess coaptation.
View larger version (51K):
[in this window]
[in a new window]
|
Fig 1. The retracted and shortened anterior leaflet with loss of coaptation is incised and augmented or lengthened with a pericardial patch to restore the zone of coaptation. After incision at point A, the pericardial patch extends from point A to A1, thereby lengthening the anterior leaflet.
|
|
View larger version (36K):
[in this window]
[in a new window]
|
Fig 2. As seen from the surgeon's view, a curvilinear incision is made in the anterior leaflet, parallel to the anterior annulus, leaving 1 to 2 mm of anterior leaflet tissue (top). This causes the anterior leaflet to "fall" or drop forward and into the ventricle (middle). The sutures for ring annuloplasty are then placed. Following adequate sizing, the pericardial patch is sewn into the anterior leaflet deficit (bottom). In the completed repair the pericardial patch assumes the majority of the area of the anterior leaflet and coaptation with the posterior leaflet is obtained.
|
|
View larger version (61K):
[in this window]
[in a new window]
|
Fig 3. In the completed repair, the intraventricular restoration of the zone of coaptation is accomplished. The pericardial patch may billow into the left atrium; however, coaptation is maintained.
|
|
Concomitant procedures were common. Twelve of the XR patients underwent simultaneous coronary artery bypass grafting with a mean of 2.4 ± 0.8 grafts/patient. Tricuspid valve repair was performed in 2 of the radiation valvulitis patients and 3 of the rheumatic heart disease patients. Aortic valve replacement occurred in 5 XR patients. Atrial septal defect repair was performed in 2 of the XR patients and 3 of the RHD patients (Table 3).
|
Results
|
|---|
The mean follow-up time was 39 ± 10 months (range 12 to 67 months) for XR patients and 12 ± 25 months (range 4 to 56 months) for RHD. Follow-up was complete in both groups.
Two of the RHD patients required reoperation. Mitral valve replacement was performed in both patients for recurrent mitral regurgitation. This occurred at and 3 and 20 months postpatch augmentation. The overall survival was 95%. There were 2 late deaths in the XR patients at 27 and 48 months. Death was due to the underlying disease in both patients. There were no deaths in the RHD patients. Clinical improvements were noted in all patients. The NYHA class improved to class I or II. Follow-up echocardiography did demonstrate stiffening of the patch; however, mitral stenosis was not created in any patient. Patients were anticoagulated for 30 days following repair.
|
Comment
|
|---|
The extensive fibrotic changes that occur in the anterior leaflet of the mitral valve following radiation to the mediastium continue to pose significant surgical challenges. These morphologic changes can also be seen in rheumatic alterations. Historically, these patients have been treated with mitral valve replacement. Few reports exist on anterior leaflet patch repair. In this study we demonstrate that these patients are amenable to repair with anterior patch augmentation. This technique utilizes autologous gluteraldehyde-treated pericardium combined with ring annuloplasty and subvalvar debridement to repair the mitral valve. This avoids the necessity of chronic anticoagulation and its associated sequela when a mechanical valve is inserted. Furthermore, mitral valve replacement is known to alter the geometry of the left ventricle [6, 7]. Mitral valve repair preserves the mitral valve apparatus and this has been shown to enhance and maintain left ventricular function [8–10]. This data indicates that mitral valve repair should be entertained, perhaps even when anticoagulation cannot be avoided. In our series, five XR patients underwent concomitant mechanical aortic valve replacement, thereby necessitating long-term anticoagulation. However, by repairing the mitral valve, the disruption of the mitral valve-left ventricular unit is not altered and heart function may be preserved.
The cause of late death in our series in the irradiated patients was related to the underlying disease, and not the return of mitral regurgitation and congestive heart failure. The overall survival in this study was 95%. The actuarial survival in patients with patch augmentation for XR is 90% (20 of 22), which is slightly better than the 82% reported by another series of valvular heart operation in patients who underwent mediastinal radiation [11]. Previous studies have indicated that in addition to malignancy, heart failure is a significant cause of late death. NYHA functional class IV symptoms, atrial fibrillation, congestive heart failure, and poor left ventricular function have been identified as preoperative factors for late cardiac death [11]. In our series the mean preoperative NYHA class was III and no patient had atrial fibrillation. In the presence of atrial fibrillation one may consider additional surgical intervention. It is the policy at our institution to perform a MAZE procedure in patients with atrial fibrillation while undergoing valve repair or replacement. Our approach to surgically treat these patients before the development of severe symptoms and left ventricular dysfunction may have a role in the favorable results. Many surgical series in this group of radiated patients have been somewhat disappointing, due to recurrent mitral regurgitation from continued tissue and leaflet shortening and retraction after repair. We did see stiffening of the patch with follow-up echocardiography. However, this approach of effectively lengthening the anterior leaflet with an overly generous patch that allow for continued retraction of the native tissue is appealing. For this reason we are not concerned with the billowing of the leaflets often seen with the oversized patch. Ultimately, mitral valve repair with anterior leaflet patch augmentation does not reverse radiation changes. But this technique avoids the need for anticoagulation and sustains left ventricular function. Ultimately this may delay the onset of heart failure as it relates to mitral valve disease and improve quality of life. Although there has been question of the durability of valvular repair with radiated tissue [11], none of the patients in our series required revision to a mechanical valve at over 3 years of follow-up. Clearly, more long-term data are necessary to reach firm conclusions.
The changes seen with radiation or rheumatic alterations are part of an anatomic disease spectrum that may include degenerative changes and endocarditis. In this setting undersizing the mitral annulus is not effective. This is in contradistinction to geometric disease in which there is dilatation of the left ventricle, and an undersized annuloplasty ring would provide significant functional benefit. Therefore, in the series presented here with anatomic disease we did not undersize the ring, but rather sized the annuloplasty ring according to the distance between the trigones.
Regarding this technique of anterior patch extension from rheumatic retraction of the anterior leaflet, extensive subvalvar debridement was performed in RHD patients enabling repair of the valve. It is important to highlight in these RHD patients, when anterior leaflet patch augmentation may not be indicated. Occasionally, RHD patients with all embracing thickened and fibrotic or even calcified subvalvar apparatus would preclude repair. These patients may be better served by mechanical replacement. Also, in the presence of shortened chordae from such advanced disease we would advocate mitral valve replacement as opposed to chordal elongation or replacement. Such maneuvers would most likely not provide long-term durability. This may explain why 2 of the RHD patients developed recurrence of mitral regurgitation and required reoperation and mitral valve replacement. These patients had an all-embracing calcified subvalvar apparatus and, although extensive debridement was performed, these patients in retrospect should have been initially considered for mitral valve replacement. Ultimately, the decision to replace the mitral valve or debride the subvalvar apparatus must be determined by the comfort level of the operating surgeon.
In this series, there was no patch augmentation of the posterior leaflet performed. This technique has been used in RHD, but has not been specifically described for the treatment of XR. In these stiff and shrunken ventricles associated with radiation one would be wary of the development of left ventricular outflow tract obstruction by systolic anterior motion (SAM) being pushed forward by an overly large augmented posterior leaflet [12].
Not surprisingly, concomitant operative procedures were common. Coronary artery bypass grafts were performed in 54% of XR patients. Twenty-two percent of XR patients underwent simultaneous aortic valve replacement. This demonstrates the extensive damage that mediastinal radiation imparts on the heart. All of these patients demonstrated diastolic dysfunction and increased ventricular stiffness. However, the need for additional procedures was not associated with increased mortality.
It is known that both radiation-induced and rheumatic valvular heart disease is a progressive and widespread process [13], that may ultimately lead to progressive deterioration of heart function. Further information and follow-up is needed to determine the extended long-term durability of patch augmentation of the anterior leaflet. However, these results demonstrate excellent utility of repair and this technique should be considered for these patients.
|
Discussion
|
|---|
DR DANIEL L. MILLER (Atlanta, GA): Dr Romano, in the patients who underwent reoperation did any of the patients undergo surgery for patch dehiscence and were there any signs of leakage related to the leaflets?
DR ROMANO: No. The rheumatic patients had a very thickened and fibrotic subvalvular apparatus. I think it was the development of refibrosis or the continued progression of the fibrotic process that led to patch failure. In retrospect these patients may have been better served by mitral valve replacement. But, no, there were no patch blowouts.
DR THORALF SUNDT (Rochester, MN): They certainly are a challenging group of patients and we frequently wind up evaluating them for transplantation a few years after their valvular procedure. I was intrigued to see the size of your patch, because certainly one of my questions in reading your abstract is what happens to progressive fibrosis, and I assume the design is that the patch is large enough such that even if the native valve shrivels up to nothing you will still have a functional valve?
Did you mention, I apologize if I missed it, what was the denominator, what fraction of the radiation patients underwent a reparative technique? I think it is a terrific paper and I am pleased you presented it here.
DR ROMANO: Of the radiation patients?
DR SUNDT: How many total radiation patients were evaluated for valvular surgery and therefore what percentage of the total had repair versus replacement? I might have missed that.
DR ROMANO: A total of 32 patients with either radiation or valvular disease were evaluated for possible repair. Ultimately 22 patients underwent anterior leaflet repair with patch augmentation.
|
References
|
|---|
- Strender LE, Lindahl J, Larsson LE. Incidence of heart disease and functional significance of changes in the electrocardiogram 10 years after radiotherapy for breast cancer Cancer 1986;57:929-934.[Medline]
- Lederman GS, Sheldon TA, Chaffey JT, Herman TS, Gelman RS, Coleman CN. Cardiac disease after mediastinal irradiation for seminoma Cancer 1987;60:772-776.[Medline]
- Hancock SL, Donaldson SS, Hoppe RT. Cardiac disease following treatment of Hodgkin's disease in children and adolescents J Clin Oncol 1993;11:1208-1215.[Abstract/Free Full Text]
- Brosius 3rd FC, Waller BF, Roberts WC. Radiation heart diseaseAnalysis of 16 young (aged 15 to 33 years) necropsy patients who received over 3,500 rads to the heart. Am J Med 1981;70:519-530.[Medline]
- Veinot JP, Edwards WD. Pathology of radiation-induced heart disease: a surgical and autopsy study of 27 cases Hum Pathol 1996;27:766-773.[Medline]
- Schuler G, Peterson KL, Johnson A, et al. Temporal response of left ventricular performance to mitral valve surgery Circulation 1979;59:1218-1231.[Free Full Text]
- Huikuri HV. Effect of mitral valve replacement on left ventricular function in mitral regurgitation Br Heart J 1983;49:328-333.[Abstract/Free Full Text]
- Goldman ME, Mora F, Guarino T, Fuster V, Mindich BP. Mitral valvuloplasty is superior to valve replacement for preservation of left ventricular function: an intraoperative two-dimensional echocardiographic study J Am Coll Cardiol 1987;10:568-575.[Abstract]
- Tischler MD, Cooper KA, Rowen M, LeWinter MM. Mitral valve replacement versus mitral valve repairA Doppler and quantitative stress echocardiographic study. Circulation 1994;89:132-137.[Abstract/Free Full Text]
- Bolling SF, Pagani FD, Deeb GM, Bach DS. Intermediate-term outcome of mitral reconstruction in cardiomyopathy J Thorac Cardiovasc Surg 1998;115:381-388.[Abstract/Free Full Text]
- Handa N, McGregor CG, Danielson GK, et al. Valvular heart operation in patients with previous mediastinal radiation therapy Ann Thorac Surg 2001;71:1880-1884.[Abstract/Free Full Text]
- Mihaileanu S, Marino JP, Chauvaud S, et al. Left ventricular outflow obstruction after mitral valve repair (Carpentier's technique)Proposed mechanisms of disease. Circulation 1988;78:78-84(3 Pt 2)I.
- Adams MJ, Hardenbergh PH, Constine LS, Lipshultz SE. Radiation-associated cardiovascular disease Crit Rev Oncol Hematol 2003;45:55-75.[Medline]
This article has been cited by other articles:
|
|
|
|
 
H. Tang, Z. Xu, L. Zou, L. Han, F. Lu, X. Lang, and Z. Song
Valve repair with autologous pericardium for organic lesions in rheumatic tricuspid valve disease.
Ann. Thorac. Surg.,
March 1, 2009;
87(3):
726 - 730.
[Abstract]
[Full Text]
[PDF]
|
|
|
Top
Abstract
Introduction
