“Torsades de pointes” and atrioventricular block

Open Access
Publisher Website
Google Scholar
Abstract
In order to elucidate the trigger factor of the production of torsades de pointes (TdP), electrophysiological study was conducted in 15 patients with atrioventricular (AV) block; 6 with TdP (TdP group) and 9 without TdP (control group). In the TdP group, all had an episode of syncope and frequent ventricular premature beats (VPBs) on routine ECG, while four (44%) had syncope and three (33%) had VPBs in the control group. Aging, QRS width, ventricular cycle length, QT interval, and block site from His bundle electrogram were similar in both groups, however the QTc interval was significantly (pc interval and frequent ventricular premature beats might induce torsades de pointes.