Torsade de pointes--a cause of Morgagni-Adam-Stokes attacks in patients with complete atrioventricular block
Antonelli, D.; Rozner, E.; Freedberg, N.A.; Turgeman, Y.
Harefuah 147(3): 204-206; 279
2008
ISSN/ISBN: 0017-7768 PMID: 18488859 Document Number: 622053
Atrioventricular block may occasionally be complicated by Torsades de Pointes inducing Morgagni-Adam-Stokes attacks. The aim of our study was to evaluate the factors of increased risk of Torsade de Pointes during atrioventricular block. We reviewed the records of 7 hospitalized patients who developed Morgagni-Adam-Stokes attack due to Torsades de Pointes resulting from atrioventricular block, while waiting for permanent pacemaker implantation. None of the patients were on antiarrhythmic drugs and no electrolyte abnormalities were present. There were 6 women and 1 man, mean age was 75 +/- 3 years. All episodes of Torsades de Pointes resulted in patients loss of consciousness and required electrical cardioversion. The mean QT and QTc intervals were 28 +/- 608 ms and 47 +/- 506 ms. respectively. The mean ventricular cycle length during atrioventricular block was 156 +/- 1476 ms. While monitoring, patients premature ventricular beats were found in 6 patients before the onset of Torsades de Pointes. Although patients with atrioventricular block may be asymptomatic or mildly symptomatic our findings suggest that Torsades de Pointes and sudden cardiac death may occur, particularly in women with QT interval longer than 600 ms and the presence of premature ventricular beats.