Anomalous Left Coronary Artery from the Pulmonary Artery: Hiding in Cath Lab

All articles of this category (opens in new window) Background: We report a case of postnatal diagnosis of Anomalous Left Coronary Artery from the Pulmonary Artery (ALCAPA), Bland-White-Garland-Syndrome, which evaded confirmation of diagnosis using gold standard diagnostic methods with coronary angiography during cardiac catheterization due to unusual hemodynamics. After an unremarkable pregnancy, our patient displayed significant signs of heart failure with delayed growth and increased perspiration, and dyspnea for several days before admission. At the local hospital, the now 2-month-old infant presented in cardiac shock with fever and lactate acidosis (16 mmol/L, pH 7). Local echocardiography raised suspicion of ALCAPA preceding transfer to the nearest pediatric cardiac center. Methods: On arrival, significantly impaired left cardiac function was confirmed on echocardiography. However, the origins of the coronary arteries could not be visualized. Laboratory results showed increased cardiac parameters with no signs of infection (troponin I: 1,200 pg/mL, proBNP: 135,000 ng/L). An emergency cardiac catheterization to confirm the suspected diagnosis demonstrated regular anatomy of the right coronary artery (RCA), but failed to visualize the origin of the left coronary artery (LCA), either from the aortic or the pulmonary arterial side. Invasive hemodynamics unveiled a systolic pressure of 80 and 49 mm Hg in the aorta and main pulmonary artery, respectively. Left ventricular end diastolic pressure (LV-EDP) measured 43 mm Hg. A subsequent cardiac CT scan did, unfortunately, not provide further information on vessel anatomy. We stabilized the infant on our ICU using Milrinone and diuretics with clinical success, reduced proBNP levels (14,000 ng/L) and normalized lactate levels, but without improvement in troponin I levels or in left ventricular function on echocardiography. A second cardiac catheterization on day 3 of admission, with invasive LV-EDP measured at 11 mm Hg, provided an unequivocal angiography of the LCA arising from the main pulmonary artery following retrograde contrast filling from the RCA. The child was operated on the same day and recovered soon after. Conclusion: Severely elevated LV-EDP in acute heart failure on initial clinical presentation “hid” the true origin of aberrant LCA during coronary angiography as the gold-standard procedure. Only repeat cardiac catheterization after successful medical stabilization for 3 days was sufficient to uncover the correct diagnosis. Publication History Article published online: 17 February 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany