The safety and efficacy of temporary cardiac pacing by bedside to interfere the torsades de points in patients with acquired long QT syndrome

Abstract

Objective To evaluate the safety and efficacy of the temporary bedside cardiac pacing in controlling torsades de points (TdP) in patients with acquired long QT syndrome (LQTS). Methods Twelve patients with acquired LQTS were enrolled from April 2003 to August 2007 consecutively and their clinical data were analyzed. Bedside cardiac pacing was adopted when other methods couldn't terminate the repeated TdP. Results Twelve patients successfully experienced the temporary bedside cardiac pacing via femoral venous. The average time spent in bedside cardiac pacing was about (10.5±2.4) min. After cardiac pacing the interval of QT and QTc were shortened [ (0.42±0.03 ) svs (0.52±0.06) s, P < 0.05; (0.43± 0.04 ) s vs (0.53±0.05 ) s, P <0.05 ]. The TdP occurred (4.6±1.2 ) times per day before cardiac pacing and it didn't reoccur any more after bedside cardiac pacing. The average time for cardiac pacing was(3.8±1.4) d. When the patients were discharged, the interval of QT and QTe were (0.41±0.02) s and (0.42±0.05) s respectively, there were significant differences compared with that before cardiac pacing(P< 0.05). During 1 year follow-up, the patients didn't experience TdP any more, and the interval of QT and QTe were (0.41± 0.06) s and (0.42±0.05) s respectively. Conclusion The immediate bedside cardiac pacing is a safe and effective way to control the repeated TdP. Key words: Long QT syndrome; Torsades de pointes; Cardiac pacing, artificial