Background: Choreoathetosis (CHO) after congenital heart surgery has been described since 1960. Risk factors and patient outcome have not been well defined.
Methods and results: As our complexity of cases increased and management of pH on cardiopulmonary bypass (CPB) evolved, we noted the appearance of CHO among patients beginning in 1986. We reviewed the hospital course and follow-up of all 19 affected children, including eight younger patients (median age, 4.3 months) who developed a mild transient form of CHO, all of whom survived and had complete resolution of CHO; seven of these eight patients had deep hypothermic circulatory arrest (DHCA). Eleven older patients (median age, 16.8 months) developed severe persistent CHO; 11 had DHCA, 10 were cyanotic, seven had anatomic pulmonary atresia, and three others were physiologically analogous with a systemic to pulmonary artery shunt-dependent circulation. Five of six patients who had pertinent preoperative angiography had systemic to pulmonary collateral vessels arising from the head and neck arteries. Mortality in severe patients was 36% (four of 11); the seven survivors showed improvement, but only one had a normal neurological examination after 60 months of follow-up. When severe CHO patients were compared with 17 age- and diagnosis-matched patients without neurological complications, no differences were found in CPB or DHCA times, arterial blood gases, or hematocrits. Time from onset of CPB to onset of DHCA (time to shutoff) was shorter in the severe persistent CHO group than for comparison patients (22 +/- 7 versus 40 +/- 29 minutes, p = 0.053).
Conclusions: Factors that may be associated with the development of severe persistent CHO include 1) age beyond early infancy, 2) cyanotic heart disease with systemic to pulmonary collaterals, particularly those arising from the head and neck vessels, and 3) the duration of the cooling period used in conjunction with deep hypothermic circulatory arrest. We advocate earlier reparative surgery, precise preoperative diagnosis and preoperative or intraoperative control of systemic to pulmonary artery collaterals, and further study of pH effects during CPB on development of CHO.