Role of arrhythmic phenotype in prognostic stratification and management of dilated cardiomyopathy.

AIMS: Dilated cardiomyopathy (DCM) with arrhythmic phenotype combines phenotypical aspects of DCM and predisposition to ventricular arrhythmias, typical of arrhythmogenic cardiomyopathy. The definition of DCM with arrhythmic phenotype is not universally accepted, leading to uncertainty in the identification of high-risk patients. This study aimed to assess the prognostic impact of arrhythmic phenotype in risk stratification and the correlation of arrhythmic markers with high-risk arrhythmogenic gene variants in DCM patients. METHODS AND RESULTS: In this multicentre study, DCM patients with available genetic testing were analysed. The following arrhythmic markers, present at baseline or within 1 year of enrolment, were tested: unexplained syncope, rapid non-sustained ventricular tachycardia (NSVT), ≥1000 premature ventricular contractions/24 h or ≥50 ventricular couplets/24 h. LMNA, FLNC, RBM20, and desmosomal pathogenic or likely pathogenic gene variants were considered high-risk arrhythmogenic genes. The study endpoint was a composite of sudden cardiac death and major ventricular arrhythmias (SCD/MVA). We studied 742 DCM patients (45 ± 14 years, 34% female, 410 [55%] with left ventricular ejection fraction [LVEF] <35%). During a median follow-up of 6 years (interquartile range 1.6-12.1), unexplained syncope and NSVT were the only arrhythmic markers associated with SCD/MVA, and the combination of the two markers carried a significant additive risk of SCD/MVA, incremental to LVEF and New York Heart Association class. The probability of identifying an arrhythmogenic genotype rose from 8% to 30% if both early syncope and NSVT were present. CONCLUSION: In DCM patients, the combination of early detected NSVT and unexplained syncope increases the risk of life-threatening arrhythmic outcomes and can aid the identification of carriers of malignant arrhythmogenic genotypes.

Sex Differences in the Long-term Prognosis of Dilated Cardiomyopathy.

BACKGROUND: Dilated cardiomyopathy (DCM) represents a specific phenotype of heart failure. Sex differences in the long-term prognosis of patients with DCM are unknown. The aim of this study is to investigate the long-term prognostic role of gender in a large cohort of patients with DCM. METHODS: A total of 1113 patients with DCM were prospectively enrolled. To investigate the impact of sex, a propensity score-matching analysis was performed on a sample of 586 patients. Univariable and multivariable Cox models and competing-risk analyses were estimated on both cohorts for the following outcome measures: (1) all-cause mortality/heart transplantation (HTx)/ventricular assist device (VAD); (2) cardiovascular mortality/HTx/VAD; and (3) sudden cardiac death or malignant ventricular arrhythmias. RESULTS: Women were older than men (50 ± 15 years vs 47 ± 15 years, respectively, P = 0.004) and more frequently had moderate to severe left ventricular dilation (P < 0.001) and left bundle branch block (P = 0.019). At multivariable analyses, male sex was independently associated with all considered outcome measures in the total cohort. At propensity score-matching analysis, over a median follow-up of 126 months (interquartile range, 62-201), 96 men (33%) vs 66 women (22%) experienced all-cause mortality/HTx/VAD (P = 0.03), 95 men (32%) vs 57 women (20%) experienced cardiovascular mortality/HTx/VAD (P = 0.025), and 46 men (16%) vs 28 women (10%) experienced sudden cardiac death/malignant ventricular arrhythmias (P = 0.07). CONCLUSION: The long-term outcomes of women affected by DCM are more favourable than those of men, and sex emerged as an important independent factor, particularly for cardiovascular outcomes.