EXTENT AND PATTERN OF REGRESSION OF LEFT-VENTRICULAR HYPERTROPHY IN PATIENTS WITH SMALL-SIZE CARBOMEDICS AORTIC VALVES

Objective: To assess the extent and pattern of regression of left vent ricular hypertrophy after valve replacement for aortic stenosis, we st udied 26 patients receiving either 19 or 21 mm CarboMedics valves (gro up I, 13 patients) or either 23 or 25 mm CarboMedics valves (group II, 13 patients). The studies were done before the operation and after 3 years, and results were compared with those of 10 control patients. Me thods: Left ventricular end-diastolic and end-systolic diameters and v olumes, ejection fraction and fractional shortening, and interventricu lar septum and posterior wall thickness were measured. The ratio betwe en interventricular septum and posterior wall thickness, the ratio bet ween left ventricular wall thickness and left ventricular chamber radi us, and the left ventricular mass were then calculated. Results: At fo llow-up there was a significant reduction in the left ventricular mass , interventricular septum, and posterior wall thickness for both patie nt groups (p < 0.01). However, only the posterior wall thickness reach ed normal values; the interventricular septum and the left ventricular mass indices were still significantly greater than in the control gro up (p < 0.01). Because of the incomplete regression of interventricula r septal hypertrophy, the ratio between interventricular septum and po sterior wall thickness was similar between both patient groups but it was significantly higher than in control subjects (p < 0.01). The rati o between wall thickness and chamber radius did not decrease significa ntly in group LI patients, in whom it remained above the control value s. Conclusion: Having a bileaflet aortic prosthesis of one size larger did not seem to significantly influence the pattern and the extent of regression of left ventricular hypertrophy after an intermediate peri od of follow-up.