Left ventricular remodeling impacts the function of the Quattro stentless mitral valve bioprosthesis (a 4-year experience)

Abstract

The St Jude Quattro stentless mitral valve prosthesis (QMV) is sutured to the mitral annulus and the papillary muscle heads, thereby preserving the subvalvular apparatus. After mitral valve replacement, remodeling of the left ventricle is often observed, causing a dilated ventricle to shrink in diameter. It was our objective to assess these changes in left ventricular (LV) geometry and evaluate its effects on the function of the QMV. From September 1997 to October 2000, 24 patients received QMV at our institution. The patients were followed up at yearly intervals (mean 4.1 +/- 2.2 years). All pre- and postoperative echocardiograms were evaluated, with attention focused on the subvalvular apparatus, leaflet morphology, and occurrence of late mitral regurgitation. In addition, all clinical outcomes and valve-related complications were recorded. Forty-one percent of patients (10/24) developed late mitral regurgitation (mild, n = 5; moderate, n = 5). The site of regurgitation was located at the 2 commissures in all cases. In 8 patients, changes in LV diameter had occurred. The point of leaflet coaptation had shifted away from the annulus in 4 patients. The overall mortality was 12.3%, and the postoperative stroke rate was 12.3%. Midterm changes in LV geometry seem to affect the competence of the QMV. Predicting these changes and subsequently adapting the sizing procedure remain a challenging task. The high rate of late valve incompetence and poor clinical outcomes has prompted us to discontinue recruitment of patients for this trial.