OasisLMS

Background: The prognostic value of serial myocardial fibrosis assessments in hypertrophic cardiomyopathy (HCM) remains to be elucidated.

Objectives: The study aims to investigate late gadolinium enhancement (LGE) progression via follow-up cardiac magnetic resonance (CMR) in HCM patients and its prognostic value.

Methods: Retrospective analysis included 313 HCM patients with 2 CMR studies (between 2010 and 2019). LGE mass progression (ΔLGE mass/y) was defined as the increase in grams of enhanced myocardium divided by interval scan years. The primary endpoint included all-cause mortality, heart transplantation, aborted sudden cardiac death, unscheduled hospitalization for heart failure, and stroke. The secondary endpoint included all-cause mortality, aborted sudden cardiac death, and heart transplantation. Maximally selected rank statistical analysis was conducted to identify the optimal cutoff for ΔLGE mass/y.

Results: LGE mass progressed from a median of 2.9 g at the first CMR study to 8.3 g at the second CMR study (median scan interval 4.2 years). During a median follow-up period of 3.4 years after the second CMR study, 69 patients reached the primary endpoint, 17 of whom reached the secondary endpoint. For the primary and secondary endpoints, the optimal cutoffs for ΔLGE mass/y were >1.50 and 3.75 g/y, respectively. Multivariable Cox regression analysis showed that ΔLGE mass/y >1.50 g/year was an independent predictor of the primary endpoint (HR: 2.22 [95% CI: 1.13-4.34]; P = 0.02). The addition of ΔLGE mass/y to the baseline model improved the discrimination (C-statistic = 0.81 vs 0.84) and risk reclassification (net reclassification improvement = 0.27, integrated discrimination improvement = 0.02; P < 0.001 for both). External validation in 6 multicenter data sets confirmed the prognostic value of ΔLGE mass/y.

Conclusions: In HCM patients, myocardial fibrosis increased over time. Serial assessments of myocardial fibrosis on CMR may improve risk stratification and clinical decision-making.

Editors
Editor-in-Chief
Y.S. Chandrashekhar, MD, DM, FACC

CME Editor
Kenneth A. Ellenbogen, MD

Authors
Talal Alnabelsi, MD, FACC