Possible sources of right-to-left shunting in patients following a total cavopulmonary connection.

Despite a good haemodynamic result, many children have a mildly decreased arterial-oxygen saturation following a total cavopulmonary connection. Our study was performed to determine possible mechanisms of right-to-left shunting in these patients. We performed elective cardiac catheterization in 19 children at a mean interval of 3.6 years following a total cavopulmonary connection. The intrapulmonary right-to-left shunt, the intracardiac right-to-left shunt and the total right-to-left shunt were calculated under mechanical ventilation with 100% oxygen. The intrapulmonary right-to-left shunt was 10.8+/-3.5% of the pulmonary blood flow, and the total right-to-left shunt accounted for 18.9+/-5.2% of the systemic blood flow. The intracardiac right-to-left shunt in patients with no relevant venovenous collaterals or leaks in the atrial tunnel was calculated at 6.4+/-3.0% of the systemic blood flow, while the intracardiac right-to-left shunt in patients with relevant collaterals or leaks accounted for 13.0+/-5.9% of the systemic blood flow. Since intrapulmonary arteriovenous fistulas were not demonstrated angiographically in any of our patients, the intrapulmonary right-to-left shunt is probably due to low ratios of perfusion to ventilation in some pulmonary segments. The intracardiac right-to-left shunt was due to leaks across the interatrial baffle, collaterals between systemic and pulmonary veins, and to the coronary sinus draining to the pulmonary venous atrium.

Color Doppler imaging of modified Blalock-Taussig shunts during infancy.

To assess the role of color Doppler echocardiography in the early postoperative evaluation of patients with a Blalock-Taussig shunt we examined 13 consecutive infants who underwent insertion of either a modified right (6 patients) or a modified left (7 patients) Blalock-Taussig shunt (age range 7 days to 6 months, mean age 8 weeks). Examination of the patients in a high parasternal right or left long axis was able to determine patency of the shunt in 12 patients. In the remaining patient, who did not show flow in the shunt, complete occlusion of the shunt was confirmed by angiography. From subcostal views we were able to demonstrate patency of the shunt in 75% of the infants and in all patients younger than 4 weeks of age. In our experience color Doppler echocardiography is a highly reliable method for early postoperative evaluation of infants with a Blalock-Taussig shunt.

Color Doppler imaging of modified Blalock-Taussig shunts during infancy.

To assess the role of color Doppler echocardiography in the early postoperative evaluation of patients with a Blalock-Taussig shunt we examined 13 consecutive infants who underwent insertion of either a modified right (6 patients) or a modified left (7 patients) Blalock-Taussig shunt (age range 7 days to 6 months, mean age 8 weeks). Examination of the patients in a high parasternal right or left long axis was able to determine patency of the shunt in 12 patients. In the remaining patient, who did not show flow in the shunt, complete occlusion of the shunt was confirmed by angiography. From subcostal views we were able to demonstrate patency of the shunt in 75% of the infants and in all patients younger than 4 weeks of age. In our experience color Doppler echocardiography is a highly reliable method for early postoperative evaluation of infants with a Blalock-Taussig shunt.

[Resection of a cardiac rhabdomyoma of the right and left ventricular outflow tract]. / Resektion kardialer Rhabdomyome des rechts- und links-ventrikulären Ausflusstraktes.

Rhabdomyomas are benign cardiac tumors often occurring as multiple lesions. We describe an infant with multiple cardiac rhabdomyomas causing severe right-ventricular and left-ventricular outflow tract obstructions. The intracavitary parts of the rhabdomyomas were successfully resected when the patient was 5 weeks old. Echocardiography showed regression in size of the remaining intramural tumors. Since there is only a low growth potential in cardiac rhabdomyomas, surgical management is indicated only in patients with hemodynamic obstruction or significant arrhythmias. Surgery should be primarily directed to relieve hemodynamic obstruction. If complete resection is not possible without damage to vital structures, resection should be restricted to the intracavitary parts of the tumor.

[Pulmonary atresia with ventricular septal defect: the significance of collateral lung perfusion for the prognosis of corrective operations]. / Pulmonalatresie mit Ventrikelseptumdefekt: Die Bedeutung der kollateralen Lungenperfusion für die Erfolgsaussichten von Korrekturoperationen.

From 1970 to 1986, 43 patients with pulmonary atresia and ventricular septal defect (PA-VSD) were diagnosed in our hospital. 19 children had a collateral lung perfusion via a ductus botalli (DB), three children had a DB and systemico-pulmonary collateral arteries (SPCA), and 21 children had only SPCA. Patients with a DB alone had significantly larger pulmonary arteries. Children with SPCA always had hypoplastic pulmonary arteries and intrapulmonary arborization anomalies and in a high percentage (19 patients) they showed intrapulmonary stenoses. 26 palliative operations were performed in 24 children. After palliative operations in 15 cases (patients with DB: RVOT-Patch: one patient, aortopulmonary shunt: three patients, Brock procedure: one patient, patients with SPCA: RVOT-Patch: five patients, aortopulmonary shunt: four patients, Brock procedure: one patient) we checked the possibility of corrective surgery with the equation of Alfieri. According to this equation, corrective surgery without excessive right ventricular pressure would have been possible in all post-operatively catheterized patients with DB after primary palliative operations but, due to the pulmonary artery anomalies, only in seven out of nine patients with SPCA (one patient of the latter group was operated twice, Brock procedure and RVOT-Patch). In four cases we could prove the value of the Alfieri equation after corrective operations. There was an excellent correlation between the predicted relation of PRV/PLV and the actually measured pressures. In our opinion, the Alfieri equation forms a valuable aid in the preoperative assessment of children with PA-VSD.