An Unusual Congenital Aortopulmonary Shunt in Tetralogy of Fallot – Anomalous Left Innominate Artery off the Pulmonary Artery
Presenter
Macken Yrun-Duffy, DO, The University of Arizona, Tucson, AZ
Macken Yrun-Duffy, DO1, Danielle D Strah, MD2, Kenneth Fox, MD3, Scott E Klewer, MD4 and Mike D. Seckeler, M.D., FSCAI1, (1)The University of Arizona, Tucson, AZ, (2)Rady Children's Hospital, San Diego, CA, (3)University of Arizona, Tucson, AZ, (4)University of Arizona, Department of Pediatrics (Cardiology), Tucson, AZ
Title:
An unusual congenital aorto-pulmonary shunt in tetralogy of Fallot - anomalous left innominate artery off the pulmonary artery
Introduction:
We present a pediatric patient who underwent transcatheter palliation of complex congenital heart disease in the setting of multiple other medical comorbidities.
Clinical Case:
5-year-old female with CHARGE syndrome, unrepaired tetralogy of Fallot, a right aortic arch with anomalous origin of left innominate artery off the main pulmonary artery, repaired esophageal atresia, Dandy-Walker syndrome and severe growth restriction with progressively worsening cyanosis not responsive to respiratory support. Due to the comorbidities, she was not a surgical candidate for cardiac repair and had relied on retrograde flow through the anomalous left innominate artery to act as an aorto-pulmonary shunt and augment pulmonary arterial flow. She developed progressively worse cyanosis (baseline systemic saturations 60%), and at 3 years old had an episode of extreme hypoxia that did not respond to mechanical ventilation and led to hypoxia-induced seizures. A prior cardiac CT had demonstrated the extracardiac vascular anatomy with the left innominate artery arising anomalously from the main pulmonary artery and echocardiography showed unrepaired tetralogy of Fallot with acquired right ventricular outflow tract atresia. Flow through the innominate artery could not be definitively seen. Urgent cath-based intervention to augment aorto-pulmonary shunting was planned.
The procedure was performed under general anesthesia with continuous cerebral NIRS monitoring. Aortic angiography showed a right arch with retrograde filling of the left innominate artery and pulmonary arteries. There was severe stenosis of the left innominate artery just above entry into the pulmonary arteries (narrowing from 8 mm to 3 mm). The left axillary artery was engaged percutaneously. A Palmaz Genesis 1910 stent was hand mounted onto an 8 mm x 2 mm OptaPro balloon. Just crossing the stenosis with the sheath caused significant obstruction of the innominate artery and profound desaturations. The stent was quickly advanced and deployed with marked improvement in branch pulmonary artery flow and systemic saturations, but no change in cerebral NIRS to suggest "steal" into the pulmonary arteries. At two-year follow-up, the stent is patent and her saturations have remained in the mid-80s% with no further seizures.
Discussion:
This case emphasizes the importance of having a thorough understanding of the complex congenital cardiac anatomy and physiology when treating these patients. Additionally, highlighted is the importance of less commonly used vascular access sites, such as the left axillary artery, in instances where anatomical abnormalities may prevent access to the areas of interest from standard approaches.