Late gadolinium enhancement on cardiac magnetic resonance predicts adverse cardiovascular outcomes in nonischemic cardiomyopathy: a systematic review and meta-analysis

Abstract

Background: Late gadolinium enhancement (LGE) by cardiac MR (CMR) is a predictor of adverse cardiovascular outcomes in patients with nonischemic cardiomyopathy (NICM). However, these findings are limited by single-center studies, small sample sizes, and low event rates. We performed a meta-analysis to evaluate the prognostic role of LGE by CMR (LGE-CMR) imaging in patients with NICM.

Methods and results: PubMed, Cochrane CENTRAL, and EMBASE were searched for studies looking at the prognostic value of LGE-CMR in patients with NICM. The primary end points included all-cause mortality, heart failure hospitalization, and a composite end point of sudden cardiac death (SCD) or aborted SCD. Pooling of odds ratios was performed using a random-effect model, and annualized event rates were assessed. Data were included from 9 studies with a total of 1488 patients and a mean follow-up of 30 months. Patients had a mean age of 52 years, 67% were men, and the average left ventricular ejection fraction was 37% on CMR. LGE was present in 38% of patients. Patients with LGE had increased overall mortality (odds ratio, 3.27; P<0.00001), heart failure hospitalization (odds ratio, 2.91; P=0.02), and SCD/aborted SCD (odds ratio, 5.32; P<0.00001) compared with those without LGE. The annualized event rates for mortality were 4.7% for LGE+ subjects versus 1.7% for LGE- subjects (P=0.01), 5.03% versus 1.8% for heart failure hospitalization (P=0.002), and 6.0% versus 1.2% for SCD/aborted SCD (P<0.001).

Conclusions: LGE in patients with NICM is associated with increased risk of all-cause mortality, heart failure hospitalization, and SCD. Detection of LGE by CMR has excellent prognostic characteristics and may help guide risk stratification and management in patients with NICM.

Keywords: cardiac magnetic resonance imaging; late gadolinium enhancement; nonischemic cardiomiopathy; prognosis.

Figures

Figure 1

Flow diagram of the review process.

Figure 2. Individual and pooled risk of cardiovascular outcomes for LGE-CMR

Forest plots comparing clinical outcomes of patients with known or suspected NICM with positive LGE and negative LGE. Outcomes included (A) all-cause mortality (B) heart failure with hospitalization, and (C) composite end point of SCD, aborted SCD, or appropriate ICD therapy.

Figure 3. Annualized event rates of cardiovascular outcomes based on the presence of LGE

Weighted mean AERs for all-cause mortality, heart failure with hospitalization, and a composite end point of SCD, aborted SCD, or appropriate ICD therapy comparing patients with LGE on CMR (blue) and patients without LGE on CMR (red).