Anomalous systemic arterial supply to normal basal segments of the left lower lobe.

BACKGROUND: Anomalous arterial supply to the normal basal segments of the lower lobe without sequestration is a rare congenital abnormality, and whether it belongs to the broad spectrum of sequestration disorders remains controversial. METHODS: The cases of all 4 patients who were treated surgically by us were reviewed together with 8 previously reported cases. RESULTS: The anomalous artery originated from the descending thoracic aorta, distributed to the basal segments of the left lower lobe, and drained to a normal inferior pulmonary vein in each case. The anomalous artery was thick and elastic walled. From the review of all 12 cases, male gender, left side, descending thoracic aorta as the aberrant arterial origin, absence of pulmonary blood flow to the basal segments, and normal pulmonary venous drainage were predominant. Despite some differences, the findings seemed closely related to intralobar sequestration. Surgical treatments were lung resection, anastomosis, and ligation of the anomalous artery. CONCLUSIONS: This anomaly is probably one type of sequestration complex. Both aortic and pulmonary arterial angiographic studies are needed to plan the definitive surgical procedure.