Total anomalous origin of the coronary arteries from the pulmonary artery.

The clinicopathologic features of four patients with total anomalous origin of the coronary arteries from the pulmonary artery (TCAPA) are presented and compared with 21 previously reported cases. Patients with TCAPA usually present with left ventricular heart failure, angina, or associated cardiovascular anomalies. Of the 19 patients in whom a clinical history was available, 16 were symptomatic before three days of age. All patients died with 60% dying before two weeks of age. Longer survival was associated with additional cardiovascular anomalies that increased pulmonary arterial perfusion pressure, oxygen saturation, or both. Seventeen (68%) patients had additional cardiovascular anomalies, most commonly atrial (nine cases) or ventricular (eight cases) septal defects and tetralogy of Fallot or other variants of pulmonary atresia (four cases). Only five (22%) of 23 had noncardiovascular anomalies. The coronary arteries arose equally from either one ostium or from two, and the number of ostia was not related to either anomalous coronary artery distribution or to the presence of additional cardiovascular anomalies. Cardiomegaly was present in 56% of cases and the majority of patients had myocardial fibrosis or infarction. Embryology is reviewed and evidence is presented to support the theory of involution-persistence of coronary artery anlagen as the pathogenetic mechanism of TCAPA.