Open Access“Torsades de pointes” and atrioventricular block
Author(s) -
Moroe K.,
Saku K.,
Tashiro N.,
Hiroki T.,
Arakawa K.
Publication year - 1988
Publication title -
clinical cardiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.263
H-Index - 72
eISSN - 1932-8737
pISSN - 0160-9289
DOI - 10.1002/clc.4960110111
Subject(s) - medicine , torsades de pointes , atrioventricular block , cardiology , heart block , anesthesia , block (permutation group theory) , electrocardiography , qt interval , geometry , mathematics
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 QT c interval was significantly (p<0.01) longer in the TdP group than in the control group (580±112 vs. 459±37, respectively). Furthermore, four patients (67%) in the TdP group showed advanced AV block in which a slow ventricular rate and an irregular rhythm were characteristic, whereas only one control (11%) showed advanced AV block and all other control patients (89%) had complete AV block. These data indicate that patients with advanced atrioventricular block associated with prolonged QT c interval and frequent ventricular premature beats might induce torsades de pointes.