Does cardiac resynchronization therapy improve symptoms and reduce morbidity in patients with symptomatic heart failure (NYHA III-IV, LVEF <= 35%, QRS >= 130 ms)?
CRT is an effective therapy for improving symptoms and reducing morbidity in selected patients with symptomatic heart failure and electromechanical dyssynchrony.
Cardiac resynchronization therapy (CRT) is a new therapeutic approach for a selected group of patients with symptomatic heart failure (NYHA functional class III-IV) despite optimal medical therapy, due to dilated cardiomyopathy of any etiology (left ventricular ejection fraction or = 55 mm), who present with electromechanical dyssynchrony (QRS > or = 130 ms). Safety and effectiveness of CRT have been demonstrated by several clinical trials, with patients achieving significant improvement in both clinical symptoms as well as functional status and exercise capacity. Furthermore, CRT has reduced morbidity of heart failure patients, while its impact in improving survival still remains to be clarified. Whether or not heart failure patients candidate to CRT should receive a defibrillator back-up remains debatable, although growing evidence is pointing to extensive use of a defibrillator in such a population.
Auricchio et al. (2004) studied this question.