Prognostic significance of late gadolinium enhancement on cardiac magnetic resonance in patients with hypertrophic cardiomyopathy

Background: Late gadolinium enhancement (LGE) on cardiac MRI indicates the myocardial fibrosis in hypertrophic cardiomyopathy (HCM), and the prognostic value of LGE in HCM has been described in several studies, but controversy exists given the limited power of these studies to predict future adverse cardiac events. The objective of this study was to perform a meta-analysis to systematically evaluate the predictive value of LGE on cardiac magnetic resonance (CMR) for future adverse cardiac events. Methods: We systematically searched multiple database including PubMed, EMBASE, and Cochrane Library for cohort studies of the effects of LGE on clinical outcomes (sudden cardiac death (SCD)/aborted SCD, all cardiac death, and all-cause mortality) in patients with HCM. We performed a meta-analysis to determine pooled odds ratios (OR), weighted average annualized event rates, and summary receiver operating characteristic (SROC) curves for these clinical events. Results: We identified nine clinical studies, examining 1734 patients with LGE and 2036 without LGE, and an average follow-up of 2.9 years. The weighted average annualized event rates of SCD/aborted SCD in patients with HCM (positive LGE versus negative LGE) was 1.28% versus 0.32% (p < 0.001), and the pooled OR was 3.40 (95% CI: 1.90, 6.08; p < 0.001). The sensitivity and specificity of predicting future cardiac events were 0.83 (95% CI: 0.66, 0.93) and 0.45 (95% CI: 0.31, 0.59), respectively. The 5-year risk of SCD/aborted SCD was 6.4% in patients with LGE. The all cardiac death and all-cause mortality were also significantly increased in patients with LGE. However, the extent of LGE was not significantly related to the risk of SCD/aborted SCD. Conclusions: LGE is significantly associated with SCD/aborted SCD risk, all cardiac death and all-cause mortality in patients with HCM. Implantable cardioverter defibrillators (ICD) can be considered for those patients with LGE. (C) 2017 Elsevier Inc. All rights reserved.