No abstract

The majority of sudden deaths after repair of tetralogy of Fallot have been presumed to be due to ventricular arrhythmia; however, it remains to be demonstrated that antiarrhythmic medication reduces the incidence of sudden death. Since 1978, ventricular arrhythmias have been treated aggressively; these include any ventricular arrhythmia on routine electrocardiogram and more than 10 uniform premature ventricular complexes per hour on 24 hour electrocardiogram. A review was undertaken of 488 patients followed up for more than 1 month after repair of tetralogy of Fallot (mean follow-up time 6.1 years); 13.5% had ventricular arrhythmia on routine electrocardiogram. Ventricular arrhythmia appeared from 2 months to 21 years postoperatively (mean 7.3 years). Ventricular arrhythmias were significantly (p less than 0.01) related to: longer follow-up duration, older age at follow-up, older age at operation and higher postoperative right ventricular systolic and end-diastolic pressures. Ventricular arrhythmia on routine electrocardiogram occurred in 100% of those who later died suddenly compared with 12% of those who did not die (p less than 0.01). Treatment for ventricular arrhythmia was given to 46 patients and considered "successful" if there were fewer than 10 uniform premature ventricular complexes per hour on 24 hour electrocardiogram. A successful drug was found in 44 of the 46: 30 of 34 given phenytoin, 6 of 9 given propranolol, 1 of 7 given quinidine, 1 of 2 given disopyramide, 8 of 9 given mexiletine and 4 of 5 given amiodarone.(ABSTRACT TRUNCATED AT 250 WORDS)

SUMMARY Because increasing numbers of patients with surgically repaired tetralogy of Fallot (TOF) are surviving to adulthood, this study was done to provide follow-up data for physicians concerned with their care. We reviewed the current status of 233 patients born before January 1962 who had repair of TOF at a median age of 9.7 years (range 11 months to 36 years). There were 26 surgical deaths (11.1%), 12 late cardiacrelated deaths (5.9%) and three noncardiac deaths (1.3%). Eight of the 12 late deaths occurred suddenly and unexpectedly. In each of these eight patients we had previously documented elevated right ventricular systolic pressure as well as ventricular premature depolarizations (VPDs). Among the 95 patients who responded to a questionnaire, 84 denied symptoms, 28 were married, 44 had attended college and all were employed. Cardiac catheterization revealed an unsatisfactory hemodynamic result in 39 of 120 patients, 30 of whom were asymptomatic. The poor result was due to a large left-to-right ventricular shunt in eight patients, persistent right ventricular outflow obstruction in 25 patients, pulmonary vascular obstructive disease in five patients, and left ventricular cardiomyopathy in one patient. Among the 21 patients with VPDs, 17 underwent cardiac catheterization: 15 had a right ventricular systolic pressure > 60 mm Hg and all had elevated right ventricular end-diastolic pressure. We conclude that 1) clinical assessment alone is nonpredictive of the hemodynamic result and thus cardiac catheterization is indicated in all patients; 2) the combination of persistent elevation of right ventricular systolic pressure above 60 mm Hg and VPDs placed the patient at risk for sudden death; and 3) over 80% of adults with repaired TOF can lead a normal life without impairment of intellect, exercise tolerance or fertility.