The Association between Aortic Valve Weight, Echocardiographic Indices, and All-Cause Death in 1,046 Patients Undergoing Surgical Aortic Valve Replacement for Aortic Stenosis

Abstract

Background: Aortic valve weight (AVW), a flow independent measure of aortic stenosis (AS) severity, is reported to have heterogeneous associations with the echocardiographic variables used for AS evaluation. Controversy exists regarding its impact on survival after aortic valve replacement (AVR). Objective: We sought to determine the association between AVW with echocardiographic measures of AS severity and all-cause mortality after surgical AVR. Methods: One thousand and forty-sixconsecutive patients underwent surgical AVR for AS, the excised valves were weighed, and an echocardiogram was done before surgery. Results: Males had heavier valves than females, for both absolute and body surface are (BSA)-indexed values (2.78 ± 1.23 vs. 2.08 ± 0.68 g, p < 0.001; and 1.38 ± 0.61 vs. 1.19 ± 0.41 g/m2, p < 0.001, respectively). In a restricted cohort of 634 patients with isolated severe AS and normal ejection fraction, the correlations of AVW with echocardiographic variables of AS were modest, the strongest being with the dimensionless index (r = –0.27 and –0.26 for male and female, both p < 0.01). Stratified by stroke volume index and mean gradient (MG), no associations were found in the low-gradient groups (i.e., MG <40 mmHg). At a median follow-up of 3.5 years, there were only 244 deaths in the entire cohort. Mortality was not related to AVW, except in females who displayed an inverse relationship (HR = 0.67; 95% CI 0.47–0.95) only when it was analyzed as a continuous variable. Conclusions: The weak correlation between AVW with the echocardiographic indices of AS may reflect its complex pathophysiology, heterogeneous hemodynamics, and possible pitfalls in the current echocardiographic methods used in clinical practice. The prognostic value of AVW after AVR warrants further evaluation.