Pulmonary function thirteen to twenty-six years after repair of tetralogy of Fallot

Abstract

Lung function was evaluated in 68 patients 13 to 26 (median 19) years after repair of tetralogy of Fallot. Age at repair was 7 years (9 months to 42 years) and 51% had a palliative shunt. An outflow patch was inserted in 56%. Median vital capacity was 84% of predicted, forced expiratory volume in 1 second 83%, maximal voluntary ventilation at 40 breaths/min 70%, and diffusing capacity for carbon monoxide 77% of predicted. Scintigraphy demonstrated abnormal pulmonary perfusion in 86%. Average right lung perfusion was 57% (predicted 52%). Regional hypoperfusion could in some patients be explained by previous palliative shunt, pulmonary artery obstruction, or presence of aortopulmonary collaterals. Median symptom-limited work capacity was 82% (95% confidence limits 78% to 90%) of predicted. Twenty-eight physically active patients had high values for symptom-limited work capacity, vital capacity, forced expiratory volume in 1 second, and maximal voluntary ventilation at 40 breaths/min compared with those of inactive patients. Lung function variables were related to physical exercise and previous palliative shunt. Moderate or severe pulmonary valve incompetence had negative but not significant influence on lung function. There was no significant influence of acyanosis before repair, use of transannular patch, duration of follow-up, or smoking. We found moderately reduced work capacity and lung function late after repair of tetralogy of Fallot that did not cause symptoms. Lung function variables were high in young active male patients and low in patients with previous palliative shunt. A better lung function in active patients indicates that physical activity should be encouraged after repair of tetralogy of Fallot.