Prognostic Implications of Left Ventricular Scar Determined by Late Gadolinium Enhanced Cardiac Magnetic Resonance in Patients with Atrial Fibrillation

Abstract Left ventricular (LV) scar identified by late gadolinium enhanced (LGE) cardiac magnetic resonance (CMR) is associated with adverse outcomes in coronary artery disease (CAD) and cardiomyopathies. We sought to determine the prognostic significance of LV-LGE in atrial fibrillation (AF). We studied 778 consecutive patients referred for radiofrequency ablation of AF who underwent CMR. Patients with CAD, prior myocardial infarction (MI), or hypertrophic or dilated cardiomyopathy were excluded. The endpoints of interest were major adverse cardiac and cerebrovascular events (MACCE), defined as a composite of cardiovascular death, MI and ischemic stroke/transient ischemic attack (TIA). Of the 754 patients who met the inclusion criteria, 60% were male with an average age of 64 years. Most (87%) had a normal LV ejection fraction of ≥55%. LV-LGE was found in 46 (6%) patients. There were 32 MACCE over the mean follow-up period of 55 months. The MACCE rate was higher for patients with LV-LGE (13.0% versus 3.7%; p=0.002). In multivariate analysis, CHA2 DS2 -VASc Score (hazard ratio (HR)=1.36; 95% confidence interval(CI): 1.05-1.76), the presence of LV-LGE (HR=3.21; 95%CI: 1.31-7.88) and LV-LGE extent (HR=1.43; 95%CI: 1.15-1.78) were independent predictors of MACCE. Additionally, the presence of LV-LGE was an independent predictor for ischemic stroke/TIA (HR=3.61; 95%CI: 1.18-11.01) after adjusting for CHA2 DS2 -VASc Score. In conclusion, the presence and extent of LV scar identified by LGE-CMR were independent predictors of MACCE in AF patients.