WORK CAPACITY AND CENTRAL HEMODYNAMICS 13 TO 26 YEARS AFTER REPAIR OFTETRALOGY OF FALLOT

Exercise tests and cardiac catheterization were performed in 53 patien ts, 13 to 26 years after intracardiac repair of tetralogy of Fallot. A t the time of repair, the median age was 7 years, and 60% of patients with cyanosis had had a previous palliative procedure. The right ventr iculotomy was closed without a patch in 21 patients (40%), a patch res tricted to the right ventricle was inserted in 18 patients (34%), and in 14 (26%) the patch extended across the pulmonary anulus. At follow- up, 91% of the patients were free of symptoms. Symptom-limited work ca pacity was 87% of the predicted value (95% confidence limits, 82% to 9 4%). Work capacity was inversely related to age at follow-up, to right ventricular systolic pressure at rest, and to presence of moderate or severe pulmonary valve regurgitation. Cardiac output in relation to o xygen uptake was reduced in 74% of patients during exercise. In 12 pat ients (23%), systolic pressure at rest in the right ventricle was 50 m m Hg or higher. Systolic pressure during exercise in the right ventric le was lower in patients without a patch than in those with a patch an d was abnormally high in all groups compared with healthy subjects. Th e ratio of right to left ventricular pressure was significantly lower than measurements taken immediately after repair, An intracardiac left -to-right shunt was present in 6 patients (11%). Three patients requir ed invasive treatment as a result of our follow-up. We conclude that w ork capacity was moderately reduced 13 to 26 years after repair of tet ralogy of Fallot and,vas adversely influenced by right ventricular hyp ertension and pulmonary valve regurgitation. Intermittent lifelong sur veillance is advocated, because patients without symptoms may have hem odynamic abnormalities that necessitate intervention.