Maack et al. [70] recently reported on switching between β blockers (metoprolol and carvedilol) in 68 patients treated with either agent for 1 year who had improved in terms of LVEF and NYHA class.

Lancet 353(9146), 9–13 (1999). Colucci WS, Kolias TJ, Adams KF et al. Metoprolol reverses left ventricular remodeling in patients with asymptomatic systolic dysfunction: the Reversal Of ...