FORMATION OF THROMBUS IN THE RESIDUAL PULMONARY TRUNK AND REGURGITATION OF THE PULMONARY VALVE AFTER TOTAL CAVOPULMONARY CONNECTION

The procedure of total cavopulmonary connexion includes trans-section and closure of the pulmonary trunk, the systemic venous blood flow bei ng directed to the pulmonary vascular bed by an anastomosis of the sup erior caval vein with the right pulmonary artery. Following this proce dure, there remains a small residual pulmonary trunk. The purpose of o ur study was to obtain information about the fate of this residual tru nk and its contained pulmonary valve. Using transthoracic echocardiogr aphy, we examined 29 patients (mean age 7 years 4 months) after a tota l cavopulmonary connexion (mean interval 17 months). We were able to o btain adequate visualization of the pulmonary valve and the pulmonary trunk in 23 of the patients. Pulmonary regurgitation was demonstrated by colour Doppler echocardiography in 13 pts (57%). Formation of throm bus in the residual pulmonary trunk was detected in one patient (4%) 6 months after the operation. One cerebrovascular embolic event occurre d in a patient who had pulmonary regurgitation without formation of th rombus in the residual trunk 3 months after the total cavopulmonary co nnexion. Our findings show that pulmonary regurgitation is frequently present in patients after total cavopulmonary connexion. Although form ation of thrombus in the residual pulmonary trunk seems to be less com mon, we recommend surgical closure of the pulmonary valve during this procedure so as to exclude the residual pulmonary trunk as a possible source of systemic emboli.