Management of Heart Block

Abstract

Syncope or dizzy spells with near syncope are common in the elderly. Whether or not there is gross bradycardia, such symptoms require, among other investigations, an ECG. If the ECG taken between attacks shows complete block, the likelihood is that the syncope (Stokes-Adams attack) is due to a temporary cessation of the cardiac rhythm. Asystole, ventricular tachycardia, or ventricular fibrillation may each occur. Such attacks can be reliably prevented only by artificial pacing. Although long-acting isoprenaline has often been used, there is little or no evidence that any drug therapy is effective. If the ECG taken between syncopal attacks shows lesser degrees of block or bundle branch block, it is highly probable that the syncope is cardiogenic, although many of these rhythms without syncope are relatively benign. Syncope from cessation of the heartbeat is exceptional when the ECG between attacks shows no conduction defect. Syncopal attacks associated with block are usually both infrequent and unpredictable; thus, continuous monitoring to determine the rhythm during an attack is usually impractical.