Objective: To evaluate the prognostic value of late gadolinium enhancement (LGE) in myocarditis and clinically suspected myocarditis.
Methods: The study was registered in PROSPERO (CRD42019144976). A systematic search of PubMed, Ovid Medline, Embase, Web of Science and the Cochrane Central Register of Controlled Trials was completed. Major adverse cardiac event (MACE) was defined as the combination of all-cause mortality or cardiovascular death, resuscitated cardiac arrest, heart transplantation, appropriate implantable cardioverter-defibrillator shock, rehospitalisation following a cardiac event and recurrent acute myocarditis. Combined outcome was defined as the combination of all adverse events. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate the prognostic value of LGE.
Results: Eight articles including 1319 patients (mean age, 38.8 ± 12.9 years) were included in the meta-analysis. The study showed that positive LGE was strongly associated with an increased risk of combined outcome (pooled OR, 5.85; 95% CI, 2.88 to 11.86; p < 0.001) and of MACE (pooled OR, 4.57; 95% CI, 2.18 to 9.59; p < 0.001). Additionally, in a subgroup analysis with mean ejection fraction (EF) point of 50%, the pooled ORs for the combined outcome were 6.46 for left ventricular EF (LVEF) > 50% and 7.90 for LVEF ≤ 50%, and the pooled ORs for MACE were 9.03 and 3.45, respectively. After 3 years of follow-up, the worse outcomes occurred mainly in patients with positive LGE.
Conclusion: Positive LGE is a powerful prognosticator of adverse outcome in myocarditis and clinically suspected myocarditis, irrespective of LVEF.
Key points: • Forty-four percent to 100% of myocarditis patients have positive late gadolinium enhancement. • Positive LGE was a powerful prognosticator of adverse outcome in myocarditis and clinically suspected myocarditis, irrespective of LVEF. • LGE-CMR is important tool for risk stratification in myocarditis and clinically suspected myocarditis.
Keywords: Fibrosis; Magnetic resonance imaging; Meta-analysis; Myocarditis; Prognosis.