Sex Differences in Sudden Cardiac Death During Long-Term Follow-up in Patients With Chronic Heart Failure - A Report From the CHART-2 Study.

Background: Although sudden cardiac death (SCD) generally occurs more frequently in men than in women, there are limited data on sex differences in SCD in patients with chronic heart failure (HF) across a range of left ventricular ejection fraction (LVEF).

Methods and results: We examined sex differences in SCD incidence, timing, and risk factors in 4,683 patients with chronic HF (3,186 men, 1,497 women) from a multicenter prospective observational cohort study (CHART-2). Over a median follow-up of 8.8 years after study enrollment, there were 215 SCDs (160 in men, 55 in women). The SCD incidence rates in men and women were 6.1 and 4.6 per 1,000 person-years, respectively (P=0.088). Among women, more than half the SCDs occurred in the first 5 years of follow-up. Beyond 5 years, the SCD incidence rate was significantly lower in women than in men (3.6 vs. 5.9 per 1,000 person-years, respectively; P=0.044). After adjusting for confounders, age, increased B-type natriuretic peptide, and LVEF <50% were common prognostic factors. After 5 years of follow-up, left ventricular (LV) enlargement was a risk factor for SCD in both sexes.

Conclusions: These results indicate that there are sex differences in SCD, especially beyond 5 years of follow-up, with a lower prevalence in women. LV enlargement is a common long-term prognostic factor in both sexes, suggesting the importance of preventing LV remodeling in HF management.