Long-term hemodynamic and electrocardiographic assessment following operative repair of tetralogy of Fallot.

To evaluate the long-term results of operative repair of tetralogy of Fallot, the cardiovascular, clinical, and electrocardiographic status was evaluated in 21 patients who had undergone operation 5 to 19 years previously. All patients were asymptomatic. Major functional abnormalities detected were enlarged right ventricular dimension in 15 of 17 patients, and elevated right ventricular systolic pressure during maximal exercise (mean, 69 +/- 5 mm Hg). Nevertheless, all patients had normal or nearly normal cardiovascular responses to maximal exercise as measured by cardiac output, maximal oxygen consumption, and left ventricular ejection fraction. Significant ventricular arrhythmias were detected during 24-hour ambulatory monitoring in 14 of 21 patients. Multiform ventricular premature beats (VPBs) were seen in 13 of 14 patients, couplets in four patients, greater than 30 VPBs for at least 1 hour in three, 4-complex ventricular tachycardia in one, and repeated R on T episodes in one. Although clinical and hemodynamic function was excellent in most patients, close follow-up is still necessary to determine the significance of the high-grade ventricular arrhythmias detected and if late manifestations of cardiovascular deterioration will occur.