Anomalous Origin of the Right Coronary Artery from the Pulmonary Artery

Reviewing the Spectrum of Diagnostic and Management Strategies in a Preemie and Septuagenarian

Aron Z. Evans, MD; Jennifer R. Maldonado, BS; Umang Gupta, MD; Ravi Ashwath, MD

Introduction

Anomalous origin of a coronary artery from the pulmonary artery is a rare congenital cardiac anomaly with two main subtypes.[1] The more common, anomalous left coronary artery from the pulmonary artery (ALCAPA), receives significant attention due to its high mortality rate in early childhood; however, anomalous origin of the right coronary artery from the pulmonary artery (ARCAPA) is less well-known.[1] Unlike ALCAPA, which typically presents with congestive heart failure and death within the first year of life, cases of ARCAPA are usually discovered incidentally in asymptomatic patients; however, these patients still carry an increased risk of myocardial ischemia and sudden cardiac death secondary to the coronary steal phenomenon, so the recommended treatment has historically been surgical correction regardless of symptoms.[1-7]

FIGURE 1 Suprasternal view showing hypoplastic distal transverse arch and isthmus (TAo = Transverse arch)

Until the mid-1980’s, coronary artery anomalies were primarily diagnosed postmortem, intraoperatively, or by coronary angiography.[4,5,8] Presently, noninvasive imaging such as echocardiography has been increasingly utilized in the diagnosis of ARCAPA, with coronary angiography still considered the “gold standard.” However, advances in cardiac computed tomography angiography (CTA) now allow the ability to display higher quality information while avoiding invasive heart catheterization.[6,9,10] In select cases, when myocardial viability is in question, cardiac magnetic resonance imaging (MRI) may be used.[6]

The relative lack of review literature on ARCAPA along with its considerable variation in presentation makes diagnosis and management a challenge. Here, we describe two contrasting cases of ARCAPA in a preemie and septuagenarian which together showcase: the diagnostic approach, the role of complementary imaging, and how conservative management may be preferred over surgical correction in the appropriate clinical setting.

FIGURE 2 Parasternal short axis view showing anomalous origin of right coronary artery from facing sinus of pulmonary artery (ARCAPA = Anomalous right coronary artery from pulmonary artery; PA = Pulmonary artery; Asc Ao = Ascending aorta)

Case Presentations

Case 1: A 36-week premature infant with a prenatal diagnosis of coarctation of the aorta was born with a birth weight of 1.6 kg and required prostaglandin therapy. Postnatal transthoracic echocardiogram (TTE) findings confirmed long-segment coarctation of the aorta (Figure 1) and a nearly-closed perimembranous Ventricular Septal Defect. Then, suspicion of ARCAPA was raised (Figure 2). Due to the infant’s small size and stable condition, a cardiac CTA was delayed until two months of age; it later confirmed ARCAPA originating from the anterior sinus of the pulmonary artery and a mildly hypoplastic distal arch with coarctation of the aorta (Figure 3). When the patient’s weight was deemed appropriate at three months of age, surgical repair of both the anomalous right coronary artery and aortic coarctation was performed. The infant is now 20 months old, asymptomatic, and thriving.

To read the full article, please go to the February 2021 Issue of CCT.