Long-term results after surgical repair of total anomalous pulmonary venous connection--hemodynamic evaluation of pulmonary venous obstruction with isoproterenol infusion.

To evaluate late pulmonary venous obstruction following surgical repair in patients with total anomalous pulmonary venous connection, which may be disclosed at high cardiac output but not at rest, a hemodynamic study was performed using isoproterenol infusion. The study included 7 patients in NYHA class I, aged from 5 to 12 years (mean 6 years), who had undergone surgical correction in their early infancy (mean 79 days). After a routine catheterization protocol, isoproterenol was infused at a rate of 0.01 microgram/kg per min. On average, cardiac index increased from 4.8 to 8.1 L/min per m2. The pulmonary arterial and wedge pressures following isoproterenol infusion remained normal in all patients, including 1 case with mild pulmonary hypertension. These results suggest that most, if not all, patients with total anomalous pulmonary venous connection repaired in early infancy do not have any hemodynamic impairment if they show no pulmonary venous obstruction within the first 12 months following surgical correction.