Heart Block after Repair of Ventricular Septal Defect in Children

From March 1955 to April 1959, 174 patients with ventricular septal defect and 124 patients with ventricular septal defect associated with pulmonic stenosis were referred from the Section of Pediatrics of the Mayo Clinic for open intracardiac repair. Forty-eight of these 298 patients had complete heart block at some time following operation. Eighteen of the patients with heart block died in the immediate postoperative period, 18 had reversion to normal sinus rhythm, and 12 were discharged from the hospital with complete heart block. Three of these 12 patients died subsequently. Two died presumably as a direct result of complete heart block and a third died following a second open cardiac operation. Of the 9 surviving patients, 3 have had serious bradycardia or periods of asystole and 6 have no symptoms from heart block. One of 3 surgical technics was employed for all the patients in this study with variation in incidence of block with the use of each technic. Other factors that might relate to the incidence of heart block are discussed. The management of the patient with complete heart block both in the immediate post-operative period and after dismissal from the hospital is described.