Treatment of atrial flutter and rapid atrial tachycardia with endocavitary atrial pacing

Fourteen patients with atrial flutter (AFL) and rapid atrial tachycardia (AT) (8 AFL type I, 2 AFL type II and 4 AT) were treated with endocavitary atrial pacing (EAP). In 10 patients no antiarrhythmic agent was during this study and in 4 patients digoxin and/or verapamil was administered before. Conversion to sinus rhythm was successfully achieved in 7 patients, 50% (4 AFL type I and 3 AT). Primary success rate (return to sinus rhythm either immediately or after < 10 min of atrial fibrillation) was 71% (5/7) (2 AFL type I and 3 AT); delayed success (conversion to sinus rhythm in > 10 min, but < 24 h) was observed in 2 cases (29%) with AFL type I. At five patients AFL was converted in stable atrial fibrillation (4 AFL type I and 1 AFL type II). EAP failed to terminate the arrhythmia in 1 patient with uncommon AFL (type II) and 1 case with AT. EAP included single extrastimuli, coaction, single decremental atrial extrastimuli and incremental atrial pacing (burst) during AFL or AT. In conclusion, EAP is a method with few complications and has efficacy for converting AFL and rapid AT sinus rhythm or to atrial fibrillation.