[Surgical treatment of tachycardia in the preexcitation syndrome]

Successful outcome of surgical interventions for treatment of tachycardias in preexcitation syndromes can be anticipated in patients whose rhythm disturbances are attributable to delineated anatomic abnormalities, that is, accessory atrioventricular bundles as well as due to enhanced conduction subsequent to a physiologic abnormality of the normal AV conduction system. The procedure employed for surgical interruption of anomalous pathways is dependent on the localization of the accessory atrioventricular bundle. In 190 of our surgically-treated patients the Kent bundle was localized in the right ventricular free wall in 39, in the left ventricular free wall in 93, in the anterior septum in 21 and in the posterior septum in 58 patients. Interruption of AV conduction via the anomalous pathway was achieved by means of cryosurgical techniques especially in the presence of an epicardially-localized Kent bundle. Posterior septal pathways are notably problematic with respect to both localization and interruption. In the entire patient population, however, surgical interruption of the Kent bundle was possible in more than 90%. In 19 patients with enhanced AV conduction, surgical interruption of the His bundle was carried out predominantly with cryosurgical techniques.