[Evaluation of long-term postoperative status and cardiac function in patients with tetralogy of Fallot].

This study was undertaken to clarify the long-term post-operative state of patients with tetralogy of Fallot (TF). Total number of 243 patients with TF who underwent corrective surgery between 1965 and 1984 were investigated by the follow-up study. Cardiac function was evaluated by Holter ECG (for 48 patients), Treadmill exercise tolerance test (for 74 patients), and cardiac catheterization (for 56 patients). Twenty-year's follow-up revealed 13 patients (5.3%) of late deaths, and 10 of them were cardiac deaths. Three patients (1.2%) expired by sudden death. Nineteen female patients experienced 26 deliveries. No patients required artificial abortion due to heart failure during pregnancies. No baby with cardiac anomaly was born by these mothers. Holter ECG showed complex ventricular arrhythmias in 23 patients (48%). The high systolic pressure ratio of right ventricle to aorta, the old age at surgery, and the long elapsed time after surgery, were the three major aggravating factors of complex ventricular arrhythmias after the correction of TF. Treadmill tests disclosed that patients with poor exercise tolerance had low RVEF and high RVEDP, indicating that RV dysfunction limited the exercise capacity in the long-term postoperative state. Among the three methods of RV outflow tract reconstruction, the follow-up data showed that patients with right ventricular patch below pulmonary valve had better event-free rate compared to those with transannular patch or to those with extensive muscle resection without patch enlargement. Cineangiogram revealed that patients with transannular patch had biventricular enlargement, but the cardiac function did not differ among the three RV outflow reconstructive methods. Because 15 years after surgery the event-free rate decreases gradually and the arrhythmia problem becomes prominent, it is concluded that patients with TF should be followed and observed carefully even though they are currently in the healthy state.