title: Does a gender difference in response to cardiac resynchronization therapy exist?
abstract: BACKGROUND
  Cardiac resynchronization therapy (CRT) has a beneficial effect on clinical symptoms, exercise capacity, and systolic left ventricular (LV) performance in patients with heart failure. The aim of the current study was to evaluate whether a gender difference exists in response to CRT.
  
  
  METHODS
  Consecutive patients with end-stage heart failure (New York Heart Association, NYHA, class III-IV), LV ejection fraction (LVEF) < or =35%, QRS duration >120 ms, and left bundle branch block configuration underwent CRT. At baseline and 6 months post-CRT, clinical and echocardiographic parameters were evaluated; follow-up was obtained up to 5 years. The effects of CRT were compared between women and men.
  
  
  RESULTS
  The study population comprised 137 men and 36 women (mean age 66 +/- 11 years). No differences in baseline characteristics were observed except that nonischemic cardiomyopathy was more frequent in women than men (67% vs 38%, P < 0.05). In all patients, clinical and echocardiographic parameters improved significantly at 6-month follow-up. The magnitude of improvement in different parameters was similar between women and men, e.g., the improvement in NYHA Class was 0.9 +/- 0.6 in women and 1.0 +/- 0.7 in men (NS) and the increase in LVEF was 8 +/- 8% in women as compared to 7 +/- 9% in men (NS). The percentage of individual responders was not different between women and men (76% vs 80%, NS) and 2-year survival was comparable for women and men (84% vs 80%, NS).
  
  
  CONCLUSIONS
  No gender differences were observed in response to CRT and long-term survival after CRT.
authors.affiliation: Department of Cardiology, Leiden University Medical Center, The Netherlands.
authors.forename: Gabe B
authors.initials: GB
authors.lastname: Bleeker
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Schalij
authors.forename: Eric
authors.initials: E
authors.lastname: Boersma
authors.forename: Paul
authors.initials: P
authors.lastname: Steendijk
authors.forename: Ernst E
authors.initials: EE
authors.lastname: van der Wall
authors.forename: Jeroen J
authors.initials: JJ
authors.lastname: Bax
mesh_terms: D002304:Cardiac Pacing, Artificial; D016009:Chi-Square Distribution; D004452:Echocardiography; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D008297:Male; D011379:Prognosis; D012737:Sex Factors; D015996:Survival Rate; D016896:Treatment Outcome