The Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery (ALCAPA): A Rare Congenital Heart Disease as a Cause for Failure to Thrive in Early Infancy

Introduction: The Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery (ALCAPA) syndrome previously known as Bland-White-Garland syndrome is an extremely rare congenital artery anomaly that can present in infants and adults. In infants, ALCAPA usually presents with cardiomyopathy symptoms such as myocardial infarction or congestive heart failure. These patients can also present with failure to thrive.

Case Description: Patient is a 4-month-old full term female who was referred to the emergency department by her pediatric gastroenterologist for failure to thrive. Patient struggled with feeding since birth and tolerated no more than 60cc of formula every feed. She was born average for gestational age but failed to gain significant weight afterwards. Patient was started on famotidine and hydrolyzed formula. Neither change showed a significant improvement of symptoms. On the day of presentation, the patient’s weight was less than 1 percentile.

Chest x-ray showed significant cardiomegaly (Figure 1). During her feeds, the patient was noted to have increased work of breathing, with tachypnea and head-bobbing. Patient was admitted for further evaluation and monitoring. EKG showed several ST elevation and abnormal Q waves in the leads I, V1, V3, V5 and V6. This suggested ischemic injuries to the anterolateral heart. Bedside echocardiogram demonstrated significant dilated cardiomyopathy, ventricular dilation and an ejection fraction of 10% (Figure 2). The left coronary artery was not well-visualized. Patient was transferred to a tertiary facility. Subsequently, patient required an open-heart surgical procedure called Takeuchi Repair. Due to the severity of her FTT prior to the procedure and the significant surgical procedure, the patient required multi-disciplinary support to recover post discharge. Her caloric requirement remains high to make-up for the prolonged deficit and to promote recovery. Her weight gain continues to be extremely slow, requiring long term follow-up with the pediatric gastroenterologist and cardiologist.

Discussion: This case highlights the importance of maintaining a broad differential diagnosis when managing patients who present with FTT. Our patient was initially managed through nutritional and feeding interventions. The patient was able to achieve good clinical outcomes due to the timely diagnosis of ALCAPA and intervention. Significant mortality and morbidity exist for those with missed diagnoses. ALCAPA typically presents later on in infancy and may be missed during routine newborn screening. The recognition of common presentations of ALCAPA may help clinicians identify patients who may warrant more extensive work-up.

Conclusion: ALCAPA is an extremely rare congenital heart malformation that can present in early infancy. They are usually not discovered at birth and can present as failure to thrive. ALCAPA and other cardiac anomalies can be misdiagnosed and mistaken for gastroenterological disorders. ALCAPA has a high infant mortality rate. However, prompt diagnosis and early intervention can significantly improve clinical outcomes.