Left ventricular non-compaction cardiomyopathy: additional predictors of life-threatening events for selecting patients for cardioverter-defibrillator implantation

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. The aim of the study is to determine predictors of life-threatening arrhythmic events in order to identify high-risk patients requiring ICD/CRT-D implantation. Methods. The study included 155 patients with left ventricular non-compaction cardiomyopathy (NCСM), 59 (38.1%) women, 96 (61.9%) men, and a median age of 39 (28; 51) years. In addition to the standard examination, cardiac magnetic resonance (CMR) imaging with late gadolinium enhancement (LGE) was performed. The median follow-up was 36 months (6; 152). Endpoints of the study included life-threatening arrhythmic events (sustained VT/VF) requiring device implantation (ICD/CRT-D). Results. The most frequent types of arrhythmia were ventricular premature beats (VPB) >500 per day – in 64 (41.3%) pts, nonsustained ventricular tachycardia (VT) was observed in 54 (34.8%) pts, sustained VT – in 15 (9.7%) pts and permanent atrial fibrillation (AF) with episodes of nonsustained VT – in 34 (21.9%) pts. Syncope was recorded in 17 (11%) pts. Symptoms of NYHA FC III CHF were found in 28 (18.1%) pts. According to EchoCG data, the median LV ejection fraction (LVEF) was 44% (34; 54). According to LGE-CMR, 72 (46.8%) pts showed areas of myocardial fibrosis; the median volume of myocardial fibrosis was 13.2% (0.6; 58.5). During the follow-up period, life-threatening arrhythmic events (sustained VT/VF) developed in 15 pts, among which ICD – 8 and CRT-D – 7 were implanted as part of the secondary prevention of sudden cardiac death (SCD). The 3-year event-free survival rate was 88 ± 14%. In multivariate analysis, independent factors associated with the risk of life-threatening events requiring ICD/CRT-D implantation are the following characteristics: the presence of syncope (HR 12.5; 95% CI 3.9–39.7, p < 0.001), the presence of nonsustained VT (HR 11.8; 95% CI 1.5–95.1, p < 0.021) and the percentage of fibrosis volume ≥30% (HR 3.23; 95% CI 1.01–10.4, p < 0.048). Risk groups of life-threatening events were stratified based on multi-factor analysis. The three-year event-free survival rate of the high-risk group was 77.8 ± 5.8%, the low-risk group had no adverse events during the entire follow-up period, and the three-year event-free survival rate was 100%. Conclusion. The developed model of risk stratification of life-threatening events allows identifying high-risk patients for timely preventive measures.