Atrial overdrive pacing for reversion of atrial flutter after heart transplantation.

Atrial overdrive pacing is an effective treatment to terminate classic (type 1) atrial flutter. After heart transplantation, the appearance of atrial flutter may be an indication of acute allograft rejection, and in patients who have this arrhythmia we routinely perform endomyocardial biopsy. In this study we examined the efficacy of atrial overdrive pacing performed at the time of endomyocardial biopsy in the termination of atrial flutter. Endomyocardial biopsy was performed with a Caves-Scholten bioptome via a right internal jugular venous sheath. After completion of the biopsy, a J-shaped 5F bipolar pacing lead was inserted via the sheath and positioned with the lead tip directed medially against the interatrial septum or right atrial appendage. Atrial pacing was performed with stimulation rates up to 450 beats/min at 20 mA for 15 seconds. Since July 1989, 16 episodes of atrial flutter have occurred in nine patients. Twelve episodes (75%) were associated with acute rejection, which was moderate or severe in nine cases. Atrial overdrive pacing was successful in restoring sinus rhythm in 13 of 14 episodes during which it was attempted (success rate, 93%). The procedure was uncomplicated and produced minimal patient discomfort. In comparison, of eight episodes of atrial flutter (in six patients) that occurred before the routine use of atrial overdrive pacing, seven were associated with rejection. With treatment of rejection, two episodes reverted spontaneously, but on six occasions cardioversion with patients under general anesthesia was necessary to restore sinus rhythm. In conclusion, atrial flutter occurring after heart transplantation is usually associated with acute allograft rejection.(ABSTRACT TRUNCATED AT 250 WORDS)