PO-03-197 THE RISK STRATIFICATION VALUE OF LEFT VENTRICULAR EJECTION FRACTION AND LATE GADOLINIUM ENHANCEMENT ON CARDIAC MAGNETIC RESONANCE FOR PREDICTING VENTRICULAR TACHYARRHYTHMIAS IN NONISCHEMIC CARDIOMYOPATHY: A SYSTEMATIC REVIEW AND NETWORK META-ANALYSIS

Abstract

The late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) is associated with ventricular tachyarrhythmic substrate in patients with nonischemic cardiomyopathy (NICM), while the left ventricular ejection fraction (LVEF) ≤ 35% is still the sole criterion for implantable cardioverter defibrillator (ICD) implantation. To perform meta-analysis to evaluate the risk stratification value of LVEF and LGE on CMR for ventricular tachyarrhythmic events in NICM patients. PubMed and Embase databases were searched for studies reporting clinical outcomes (all-cause death, cardiovascular death, ventricular tachyarrhythmias[VTAs] and major adverse cardiovascular events[MACEs]) based on LVEF≤35% and LVEF>35% or LGE presence (LGE+) and absence (LGE-), among patients with NICM. Hazard ratios (HRs), both with 95% confidence intervals (CIs), were calculated using random effects models. Network meta-analysis was conducted for the outcome of VTAs, and four groups (“LVEF≤35%&LGE+”,“LVEF>35%&LGE+”, “LVEF≤35%&LGE-” and “LVEF>35%&LGE-”) were compared by using HRs forest plot and rank probability. Data from 7 studies (3002 NICM patients, 1524 with LVEF≤35%) were included in the final analysis. Pooled HRs demonstrated that LVEF≤35% was associated with increased risks of all-cause mortality (HR 2.42, 95% CI: 1.66 to 3.50), VTAs (HR: 1.67, 95% CI: 1.31 to 2.14) and MACEs (HR: 2.36, 95% CI: 1.70 to 3.27). Meanwhile 51 studies were included (15553 NICM patients, 6828 with LGE+) in pooled analyses showing those with LGE+ more likely to encounter all-cause death (HR 2.08, 95% CI: 1.84 to 2.35) , cardiovascular death (HR 2.98, 95% CI: 1.97 to 4.50), VTAs (HR: 4.03, 95% CI: 3.12 to 5.20) and MACEs (HR: 2.79, 95% CI: 2.36 to 3.31). Network analysis composed of 3 studies (2342 NICM patients) with "LVEF>35%&LGE-" serving as the control group, found that a significant reduction in VTAs-free survival for both "LVEF≤35%&LGE+" (HR: 5.2, 95% CI: 3.1 to 8.7) and "LVEF>35%&LGE+" (HR: 5.8, 95% CI: 3.4 to 10.0), while "LVEF≤35%&LGE-" showed no significant value in predicting VTA events (HR: 1.9, 95% CI: 1.0 to 3.5). Both LVEF and LGE are highly sensitive predictor of mortality, VTAs and MACEs in NICM patients. LGE integrated with LVEF significantly improved the risk stratification for VTAs compared with LVEF alone to further discriminate those NICM who will benefit from ICD.