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 being directed to the pulmonary vascular bed by an anastomosis of the superior caval vein with the right pulmonary artery. Following this procedure, there remains a small residual pulmonary trunk. The purpose of our study was to obtain information about the fate of this residual trunk and its contained pulmonary valve. Using transthoracic echocardiography, we examined 29 patients (mean age 7 years 4 months) after a total cavopulmonary connexion (mean interval 17 months). We were able to obtain 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 thrombus in the residual pulmonary trunk was detected in one patient (4%) 6 months after the operation. One cerebrovascular embolic event occurred in a patient who had pulmonary regurgitation without formation of thrombus in the residual trunk 3 months after the total cavopulmonary connexion. Our findings show that pulmonary regurgitation is frequently present in patients after total cavopulmonary connexion. Although formation of thrombus in the residual pulmonary trunk seems to be less common, 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.