Nonpharmacologic treatment of supraventricular tachycardia

During the last 2 decades, more than 1,000 patients have undergone surgical division of an accessory pathway; many refinements in epicardial mapping and surgical techniques have been made. In institutions where the procedure is routinely performed, the rate of successful accessory pathway interruption now approaches 98%. Concomitant risk of complete heart block among patients with posteroseptal pathways has declined to less than 5%. Among patients with other organic heart disease, myocardial preservation techniques result in mortality rates within 1 to 2%; among those with significant cardiac abnormalities, the mortality rate is 4 to 6%. Two techniques are generally used to ablate an accessory pathway: the endocardial and the epicardial. The aim of both approaches is to identify the site of the accessory pathway and disarticulate the atrioventricular groove or expose and ablate the atrioventricular junction to interrupt accessory pathway conduction. Although each technique has its advantages, the choice of technique is far less important than the skill of the surgeon and clinical electrophysiologist performing the procedure. Newer surgical techniques include application of external epicardial shocks in the area of the accessory pathway and use of a cryosurgical probe in the sinus to ablate accessory pathways. Whereas our current thought is that surgery should be limited to those adults who fail to respond to pharmacologic therapy, advances in atrial endocardial and epicardial mapping, as well as surgical techniques, may expand the role of surgery in the treatment of ectopic atrial tachycardia.