The extent of late gadolinium enhancement predicts mortality, sudden death and major adverse cardiovascular events in patients with nonischaemic cardiomyopathy: a systematic review and meta-analysis.

Aim: To conduct a systematic review and meta-analysis with the objective of evaluating the prognostic value of extent of myocardial fibrosis by late gadolinium-enhanced cardiac magnetic resonance imaging (CMR) in non-ischaemic dilated cardiomyopathy (NICM).

Material And Methods: The databases PubMed, EMBASE, and Google Scholar were searched for studies that investigated the prognostic value of quantification of late gadolinium enhancement (LGE) in patients with NICM. Unadjusted and adjusted hazard ratios (HRs) of uniformly defined predictors were pooled for meta-analysis.

Results: Fourteen studies were retrieved from 884 publications for this systematic review and meta-analysis. In total, 4,336 patients (mean age 51.2 years; mean follow-up 35.1 months) were included in the analysis. Meta-analysis showed the extent of LGE was associated with an increased risk of all-cause mortality (HR: 1.07/1% LGE; 95% confidence interval [CI]: 1.03-1.11; p=0.0003), composite arrhythmic endpoint (HR: 1.09/1% LGE; 95% CI: 1.03-1.15; p=0.002) and major adverse cardiovascular events (MACE; HR: 1.06/1% LGE; 95% CI: 1.02-1.11; p=0.005). After adjusting for baseline characteristics, the higher extent of LGE remained associated with the risk of all-cause mortality (HR: 1.07/1% LGE; 95% CI: 1.00-1.14; p=0.04), also strongly associated with the risk of composite arrhythmic endpoint (HR: 1.07; 95% CI: 1.02-1.012; p=0.004) and MACE (HR: 1.04; 95% CI: 1.01-1.08; p=0.005).

Conclusions: Extent of LGE in CMR predicts all-cause mortality, arrhythmic events, and MACE. Collectively, these findings emphasise that extent of LGE by CMR may have value for optimising current predictive models for clinical events or mortality in patients with NICM.