|
|
||||||||
Ann Thorac Surg 2004;77:1443-1445
© 2004 The Society of Thoracic Surgeons
a Department of Surgery, Division of Cardiothoracic Surgery, Westchester Medical Center, New York Medical College, Valhalla, New York, USA
Accepted for publication April 25, 2003.
* Address reprint requests to Dr Fleisher, Department of Surgery, Division of Cardiothoracic Surgery, Westchester Medical Center, Macy Pavilion, Rm W128, Valhalla, NY 10595, USA
e-mail: fleishera{at}wcmc.com
| Abstract |
|---|
|
|
|---|
| Introduction |
|---|
|
|
|---|
| Case reports |
|---|
|
|
|---|
Over the next 2.5 years the patient had shortness of breath with minimal exertion. He was evaluated with transthoracic echocardiography, which revealed a dilated left ventricle with normal left ventricular systolic function. Aortic insufficiency was moderate to severe. A cardiac catheterization showed severe prosthetic aortic valve regurgitation with normal coronary arteries. He was referred to our institution for reoperation. At surgery, intraoperative transesophageal echocardiography showed the central regurgitation through the valve leaflets. Examination of the valve before explantation showed an elongated cusp with prolapse and central regurgitation as a result of the lack of coaptation of the leaflets. There was no evidence of any other structural deformity or a paravalvular leak (Figs 1 and 2). The valve was replaced with a 25-mm mechanical valve.
|
|
| Comment |
|---|
|
|
|---|
The Perimount valve has been biomechanically engineered to optimize hemodynamics and durability while also providing consistent coaptation during closure. The shape and geometry of the leaflets are designed for optimal valve opening while minimizing closing stresses. Using a computer-generated design the leaflets and stent are engineered for a precise fit, which ensures uniform and consistent valve opening and closing.
All prosthetic valves exhibit some amount of regurgitation during closure. The flow pattern as visualized during echocardiography will vary based on stent design. In the Perimount valve due to the low stent profile the leaflets are shorter and straighter at the free edges compared with a porcine valve. The combination of this leaflet geometry and the wider opening area results in a higher closing volume, leading to a larger color flash along the coaptation edge during valve closure when seen under echo Doppler. Edwards Lifesciences refers to this in their educational material as the "signature flow pattern."
In addition to the shape and geometry of the leaflets the tissue characteristics of the bovine pericardium are critical for the durability and function of the valve. Tissue variability of the pericardial tissue includes the thickness of the pericardium and its stress-strain properties (the amount that the pericardium will stretch under a given pressure load).
Edwards Lifesciences was contacted and confirmed that reports such as these are extremely rare and unusual. Even in the few cases that have been reported, the event was normally explained by stent distortion, mechanical disruption, or in some cases suture tail abrasion. Despite the very low rate of occurrence, Edwards Lifesciences did indicate that it has a number of continuous improvement programs intended to improve valve manufacturability. Two of these programs relate directly to the pericardial tissue, specifically an automated thickness mapping process (Peri-Mapping), and a deflection characterization test that allows precise matching of tissue based on how the leaflets deflect under a given load (Michael Scott, PhD, personal communication, 6/19/02, written letter).
In the two cases reported here we observed none of the above-mentioned causes. Interestingly, in both cases a smaller valve was implanted at the second operation. This size change can be explained by the differences in specifically numbered sizers among different valve prostheses. In our cases we observed no differences between the sizers of the 25-mm porcine and mechanical valve versus the 27-mm pericardial valve.
We have reported an extremely rare occurrence that we believe was a result of a mismatch of pericardium of different extensile properties in our patients. Recently developed technology has allowed for quantification of deflection that can adequately match leaflet properties (Michael Scott, PhD, personal communication, 6/19/02, written letter). Edwards engineers indicated that the potential for mismatched tissue should be virtually eliminated with these enhanced manufacturing processes. Subsequent to the valve implantations detailed in this report, Edwards completed implementation of both Peri-Mapping and leaflet deflection technologies on Perimount aortic and mitral valves.
Although the second patient had an echocardiography report of mild regurgitation, this finding may have been misinterpreted or underestimated because he had a significant murmur and postoperative clinical course consistent with significant aortic regurgitation. These patients should probably have an intraoperative transesophageal echocardiography after implantation to assess baseline valve function. Excessive regurgitation should be addressed at the original operation. In addition close follow-up with serial echocardiographic scans can be obtained with some caution in dismissing early aortic insufficiency on clinical or echocardiography examination as normal.
| References |
|---|
|
|
|---|
This article has been cited by other articles:
![]() |
R. Gurvitch, D. A. Wood, E. L. Tay, J. Leipsic, J. Ye, S. V. Lichtenstein, C. R. Thompson, R. G. Carere, N. Wijesinghe, F. Nietlispach, et al. Transcatheter Aortic Valve Implantation: Durability of Clinical and Hemodynamic Outcomes Beyond 3 Years in a Large Patient Cohort Circulation, September 28, 2010; 122(13): 1319 - 1327. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Orihashi, T. Kurosaki, and T. Sueda Everted leaflet of a bovine pericardial aortic valve Interact CardioVasc Thorac Surg, June 1, 2010; 10(6): 1059 - 1060. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. F. Lopez Almodovar, P. Lima, A. Canas, J. Buendia, and E. Monguio Early structural valve deterioration of 18-mm Sorin Soprano aortic pericardial bioprosthesis J. Thorac. Cardiovasc. Surg., April 1, 2010; 139(4): e66 - e67. [Full Text] [PDF] |
||||
![]() |
T. J. Vander Salm, A. J. Toran, W. Lewis, and J. O'Connor Severe, Transient Aortic Insufficiency After Bovine Pericardial Aortic Valve Replacement: A Cautionary Note Ann. Thorac. Surg., August 1, 2009; 88(2): 672 - 674. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Buklas, M. Massetti, E. Neri, and S. Chocron Built-in defect of a biological pericardial aortic prosthesis? Interact CardioVasc Thorac Surg, December 1, 2008; 7(6): 1110 - 1111. [Abstract] [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |