Abstract 18894: The Myocardial Contraction Fraction Predicts Survival in Patients With AL Cardiac Amyloidosis. A Report From iCCAT, The International Consortium for Cardiac Amyloid Transplantation
Background: Cardiac amyloidosis is characterized by progressive ventricular thickening and diastolic heart failure. The left ventricular ejection fraction (EF) often remains normal even in advanced disease. The myocardial contraction fraction (MCF, the ratio of left ventricular stroke volume to myocardial volume) is a novel measure of myocardial shortening and may be superior to EF for predicting survival in cardiac amyloidosis.
Methods: We measured MCF and EF from two-dimensional echocardiograms obtained in 86 subjects undergoing heart transplant evaluation for AL cardiac amyloidosis. Cox proportional hazards models and Kaplan-Meier survival analysis were used to compare MCF and EF as predictors of all-cause mortality. Subjects were censored at the time of heart transplant.
Results: The mean age was 54.6 ± 7.9 years. The mean EF was 49.3 ± 12.7% and the mean MCF was 13.0 ± 5.5%. Over a median follow-up of 59 days (IQR 29-110 days), 38 subjects (44.2%) died and 48 (55.8%) underwent heart transplant. In unadjusted analyses, both MCF (HR 0.89, 95% CI 0.82-0.96, p = 0.002) and EF (HR 0.96, 95% CI 0.94-0.99, p = 0.015) predicted overall survival. In multivariate analyses adjusted for serum free light chain difference, the hazard ratio associated with each 5% absolute decrease in MCF was 2.11 (95% CI 1.32-3.38, p= 0.002). The hazard ratio associated with each 5% absolute decrease in EF was not statistically significant (HR 1.16, 95% CI 0.97-1.39, p=0.09).
Conclusions: Myocardial contraction fraction is superior to EF for predicting survival in patients undergoing heart transplant evaluation for AL cardiac amyloidosis.
Author Disclosures: V.N. Selby: None. K. Verkouw: None. J.D. Estep: None. R.M. Witteles: None. G. Feltrin: None. M. Zucker: None. D. Baran: Research Grant; Modest; Maquet. Honoraria; Modest; Maquet. D.C. Seldin: None. J. Patel: None. M. Hanna: None. T. De Marco: None. M.J. Semigran: None. M.S. Maurer: None.
- © 2015 by American Heart Association, Inc.