Age and sex as determinants of ventricular arrhythmic events in patients with decompensated congestive heart failure

Background: The propensity to develop specific arrhythmias varies between the sexes and is influenced by age. Patients with congestive heart failure (CHF) have a high prevalence of ventricular ectopy. However, in the setting of CHF, it is not known whether sex-related or age-dependent differences exist in the susceptibility to arrhythmias. Methods: The study population included 134 men and 73 women (mean age 61 +/- 14 years) admitted for decompensated CHF. The severity of ventricular arrhythmias was assessed by 24-hour Holter monitoring. None of the patients were on parenteral vasoactive therapy during Holter recording. Results: All measures of ventricular ectopy were markedly lower in women. The average hourly premature ventricular contractions (PVCs), the frequency of ventricular pairs, the mean hourly repetitive ventricular beats, and the frequency of ventricular tachycardia episodes per 24 hours were 40%, 62%, 65%, and 78% lower in women, respectively. Multivariate logistic regression revealed that the risk of developing > 3 ventricular pairs per 24-hour period (OR 2.2, CI = 1.1-4.2, P = 0.03), > 3 repetitive ventricular beats/hour (OR = 2.5, CI = 1.2-5.3, P = 0.01), or all episode of ventricular tachycardia (OR = 2.1, CI = 1.2-3.9, P = 0.01) were significantly higher in men. Patients in the higher tertile age group had a higher risk for the presence of > 3 ventricular pairs per 24-hour period (OR = 2.3, CI 1.1-4.2, P = 0.03), and the presence of > 3 repetitive ventricular beats per hour (OR = 5.9, CI 2.7-13.3, P < 0.0001), compared with patients in the lower age tertile. Conclusion: Male sex and age are associated with complex ventricular ectopy in patients with CHF. Further understanding of the mechanisms involved in the relative protection conferred by female sex would advance our understanding about arrhythmias in heart failure.