[Advantages and controversies regarding physiologic electrostimulation of the heart in sinus node disease]

Pacing mode in sinus node disease (SND) is one of controversies in cardiac pacing. We evaluated atrial pacing mode (AAI) in SND patients (pts). Between 1985 and 1994 AAI pacemaker was inserted in 179 pts due to symptomatic SND of varied etiology.

The majority of pts (91.6%) were free from syncopal episodes after AAI implantation, in 15 pts (8.4%) syncopes were occasionally observed due to disturbances in pacemaker function, AVB III degrees, vaso-vagal syndrome, orthostatic hypotonia or atherosclerotic insufficiency of the cerebral circulation. In 49 (51%) out of 96 pts with brady-tachy syndrome (BTS), episodes of supraventricular tachyarrhythmia were not observed after AAI insertion and in the majority of the remaining pts the frequency of the episodes decreased significantly. Chronic atrial fibrillation developed in 5 (5.2%) pts. In some of the pts the symptoms related to chronic heart failure decreased or disappeared. A reoperation was performed in 44 (24%) pts due to electrode dislocation or fracture, atrio-ventricular conduction disturbances, an increase in pacing threshold or due to local infections. During the follow-up period 13 (7.3%) pts died of reasons unrelated to cardiac pacing therapy.

In the majority of SND pts AAI pacing mode prevents from syncopal episodes caused by sinus node disfunction. It decreases the symptoms of heart failure in SND pts and stabilizes the sinus rhythm in the majority of BTS pts. Complications accompanying AAI do not post a major threat for the pts and can be easily resolved. They should by no means discourage from AAI implantation in SND.