Toward Sex-Specific Guidelines for Cardiac Resynchronization Therapy?

An important treatment for patients with heart failure is cardiac resynchronization therapy (CRT). Even though only 20 % of women were included in clinical trials for CRT, a benefit has been shown in recent studies for subgroups of women compared to their male counterparts. Given this low inclusion rate of women in clinical studies, professional society guideline-based CRT recommendations, such as those by the American College of Cardiology Foundation (ACCF)/American Heart Association (AHA)/Heart Rhythm Society (HRS), may not truly represent the best treatment for women, especially since most of the reports that showed this greater benefit in women were published after the latest guidelines. Despite having research and multiple publications regarding sex-specific heart failure outcomes and response to CRT, the ACCF/AHA/HRS guidelines have not yet been updated to account for the recent information regarding the differences in benefit for women and men with similar patient characteristics. This review discusses the physiology behind CRT, sex-specific characteristics of heart failure, and cardiac electrophysiology and summarizes the current sex-specific literature to encourage consideration of CRT guidelines for women and men separately.