Demographic, operative, and clinical data were obtained retrospectively through case note review. Transthoracic echocardiography was used to measure left ventricular mass preoperatively and at annual follow-up visits. Patients were classified according to their reduction in left ventricular mass at 1 year after the operation: group 1, less than 25 g; group 2, 25 to 150 g; and group 3, more than 150 g. Kaplan–Meier and multivariable Cox regression were used.
A total of 147 patients were discharged from the hospital after aortic valve replacement for aortic stenosis between 1991 and 2001. Preoperative left ventricular mass was 279 ± 98 g in group 1 (n = 47), 347 ± 104 g in group 2 (n = 62), and 491 ± 183 g in group 3 (n = 38) (P < .001). Mean time to last echocardiogram was 6.2 ± 3.2 years. Left ventricular mass at late follow-up was 310 ± 119 g in group 1, 267 ± 107 g in group 2, and 259 ± 96 g in group 3 (P = .05). Transvalvular gradients at follow-up were not significantly different among the groups (group 1, 24.8 ± 23 mm Hg; group 2, 21.4 ± 16 mm Hg; group 3, 14.7 ± 9 mm Hg) (P = .31). There was no difference in the prevalence of other factors influencing left ventricular mass regression such as ischemic heart disease or hypertension, valve type, or valve size used. Ten-year actuarial survival was not statistically different in patients with enhanced left ventricular mass regression when compared with the log–rank test (group 1, 51 % ± 9 % ; group 2, 54 % ± 8 % ; and group 3, 72 % ± 10 % ) (P = .26). After adjustment, left ventricular mass reduction of more than 150 g was demonstrated as an independent predictor of improved long-term survival on multivariate analysis (P = .02).
Our study is the first to suggest that enhanced postoperative left ventricular mass regression, specifically in patients undergoing aortic valve replacement for aortic stenosis, may be associated with improved long-term survival. In view of these findings, strategies purported to be associated with superior left ventricular mass regression should be considered when undertaking aortic valve replacement.