Prognostic role of atrial fibrillation in patients with non-compaction cardiomyopathy

Aim. To evaluate the prognostic role of atrial fibrillation (AF) as a predictor of adverse events and outcomes in a cohort of patients with non-compaction cardiomyopathy (NCCM). Material and methods . We examined 216 patients with NCCM (140 men and 76 women, median age, 39 (30; 50) years). In addition to traditional clinical methods, all patients underwent late gadolinium-enhanced cardiac magnetic resonance imaging (MRI). The endpoints of the study included progression of NYHA class III heart failure (HF) with the need for hospitalization, ventricular tachyarrhythmias, and thromboembolic events (TEEs). Results. There were 54 out of 216 (23,6%) patients with AF, of which 18 had paroxysmal AF, 16 — persistent AF, and 20 — permanent AF. During the follow-up period (median follow-up, 36 (6; 72) months), 98 out of 216 (45,4%) patients with NCCM had adverse events and outcomes as follows: 16 (7,4%) had ventricular tachyarrhythmias, of which 12 (5,6%) — sudden cardiac death with successful resuscitation and implantation of an implantable cardioverter-defibrillator; 62 (28,7%) patients had NYHA III-IV class HF progression; 20 (9,3%) patients had TEEs. The rate of adverse cardiac events was significantly higher in patients with AF (74,1% vs 35,8%, χ 2 =23,93, p<0,001) compared with patients without AF, including the incidence of TEEs (20,4% vs 5,6%, χ 2 =10,58, p=0,002) and HF progression to class III (46,3% vs 22,8%, χ 2 =10,9, p=0,002). Multivariate analysis showed that the following most significant predictors of HF progression risk: left ventricular ejection fraction (LVEF) <50% according to cardiac MRI (hazard ratio (HR), 95,8; 95% confidence interval (CI), 10,2 -898,6; p=0,0001), presence of AF (HR, 8,2; 95% CI, 2,2-31,3; p=0,0022) and left atrial volume index (LAVI) >43 ml/m 2 (HR, 5,2; 95% CI, 2,1-12,8; p=0,0004); predictors of TEE risk were the presence of AF (HR, 6,5; 95% CI, 2,0-20,8; p=0,0020) and LAVI >43 ml/m 2 (HR, 6,0; 95% CI, 1,8-19,7; p=0,036). No association of AF with ventricular tachyarrhythmias was found in the study cohort of patients with NCCM. Predictors of ventricular tachyarrhythmias were LVEF <50% (HR, 4,5; 95% CI, 2,950,4; p=0,0241) and the presence of non-sustained ventricular tachycardia (HR, 3,5; 95% CI, 1,3-9,3 p=0,0139). Conclusion. The present study shows that, along with the traditional predictor of adverse events in patients with NCCM (LVEF <50%), the identified additional predictors (AF and LAVI >43 ml/m 2 ) can be used to identify patients at high risk of complicated NCCM for the timely prevention and treatment.