Reducing Inappropriate Implantable Cardioverter-Defibrillator Shocks: Are All Beta-Blockers Equally Effective?

Beta-blockade is a mainstay of treatment for heart failure (HF), improving symptoms, and prolonging survival; it is also a first-line treatment for rate control in atrial fibrillation (AF). For HF, both metoprolol — a beta-1 receptor blocker — and carvedilol — which blocks alpha-1, beta-1, and beta-2 receptors — have demonstrated efficacy; for AF, extended-release metoprolol is generally considered to provide better rate control than carvedilol.

In the MADIT-CRT trial, 1790 patients with left ventricular ejection fraction ≤30%, wide QRS duration, and New York Heart Association class I or II HF received an implantable cardioverter-defibrillator (ICD) with or without cardiac resynchronization therapy (NEJM JW Cardiol Sep 1 2009). Although guid…