Effects of pretreatment with verapamil on early recurrences after electrical cardioversion of persistent atrial fibrillation: a randomised study. - Bertaglia, Emanuele; D'Este, Daniele; Zanocco, Albino; Zerbo, Francesca; Pascotto, Pietro; Bertaglia, E; D'Este, D; Zanocco, A; Zerbo, F; Pascotto, P (Heart, 2001)