Atrial Fibrillation and Ventricular Arrhythmias

Abstract

ABSRACT: Sex-specific differences in the epidemiology, pathophysiology, clinical presentation, clinical treatment, and clinical outcomes of atrial fibrillation (AF), sustained ventricular arrhythmias, and sudden cardiac death are recognized. Sex hormones cause differences in cardiac electrophysiological parameters between men and women that may affect the risk for arrhythmias. The incidence and prevalence of AF is lower in women than in men. However, because women live longer and AF prevalence increases with age, the absolute number of women with AF exceeds that of men. Women with AF are more symptomatic, present with more atypical symptoms, and report worse quality of life in comparison with men. Female sex is an independent risk factor for death or stroke attributable to AF. Oral anticoagulation therapy for stroke prevention has similar efficacy for men and women, but older women treated with warfarin have a higher residual risk of stroke in comparison with men. Women with AF are less likely to receive rhythm control antiarrhythmic drug therapy, electric cardioversion, or catheter ablation in comparison with men. The incidence and prevalence of sustained ventricular arrhythmias and sudden cardiac death are lower in women than in men. Women receiving implantable cardioverter defibrillators for primary prevention of sudden cardiac death are less likely to experience sustained ventricular arrhythmias in comparison with men. In contrast, women receiving a cardiac resynchronization therapy implantable cardioverter defibrillator for the treatment of heart failure are more likely to benefit than men. Women are less likely to be referred for implantable cardioverter defibrillator therapy despite current guideline recommendations. Women are more likely to experience a significant complication related to implantable cardioverter defibrillator implantation in comparison with men. Whether sex differences in treatment decisions reflect patient preferences or treatment biases requires further study.

Does Sex Modify an Association of Electrophysiological Substrate with Sudden Cardiac Death? The Atherosclerosis Risk in Communities (ARIC) Study

“…Possibly similar mechanisms are responsible for greater benefit of cardiac resynchronization therapy in women, which remain incompletely understood. 11 In this study, resting heart rate was associated with competing risk of SCD in women, but not in men ( Figure 6). Association of a resting heart rate with SCD in women was independent of incident CV events, supporting previous OregonSUDS findings.…”

“…Risk stratification of SCD for both sexes is inadequate and current practice relies on degree of left ventricular (LV) dysfunction. 10 While sex differences in cardiac electrophysiology have been recognized, 11 sex is not routinely considered a potential effect modifier of the association between electrophysiological (EP) substrate and SCD. As women develop CHD approximately 10 years later than men, women are commonly viewed as "younger men".…”

“…12 Sex differences in EP substrate are known: women have faster heart rate, narrower QRS and longer QT interval than men. 11 However, it remains unknown whether sex can modify an association of EP substrate with SCD. Recently, we expanded the armamentarium for global ECG measures of EP substrate by adding global electrical heterogeneity (GEH).…”

Gender-related Differences in Management of Nonvalvular Atrial Fibrillation in an Asian Population

“…A topic of current interest is whether gender-related differences exist in the use of health care resources for managing atrial fibrillation (AF), and whether/how these differences affect clinical outcomes. 1) 2) 3) 4) 5) Despite many advances in rhythm control methods, including radiofrequency catheter ablation, women are less likely to be selected for rhythm control strategies based on analyses of data from Europe and North America. 3) 6) 7) Although AF is less prevalent in women than in men, women with AF have a higher risk of stroke and death than men.…”

Genetic study links components of the autonomous nervous system to heart-rate profile during exercise

“…Since the polygenic risk score was not significantly associated with mother’s age of death, we could not reliably establish a true-positive association with parental age. Although, the notion that life-threatening arrhythmia’s occur more often in men than in women could explain this discrepancy 43 . Regardless, whether or not the association is a true-positive one, it is possible to conclude from our results that HR response to exercise may not be as important for the human lifespan as other more established risk factors such as blood pressure, lipids, BMI, or educational attainment 44 .…”