Single coronary artery anomaly: branching of left coronary artery from right coronary artery with 2 distinct patterns

Area of Science:

• Cardiovascular Medicine
• Congenital Heart Disease
• Interventional Cardiology

Background:

• The typical coronary artery anatomy involves separate origins for the left and right coronary arteries from their respective aortic cusps.
• A single coronary artery anomaly is a rare congenital condition, occurring in approximately 0.024% of the general population.
• This anomaly presents unique challenges in diagnosis and management due to its infrequent occurrence and variable presentation.

Observation:

• Two distinct cases of single coronary artery originating from the right coronary cusp were identified in patients presenting with angina.
• The first case involved a patient with an abnormal stress test, revealing a single coronary artery with a varicose right coronary artery and critical lesions in the posterior descending and circumflex arteries.
• The second case presented with persistent angina despite a normal noninvasive workup, showing a single coronary artery with the left coronary artery coursing between the aorta and pulmonary artery without critical lesions.

Findings:

• Coronary angiography confirmed the single coronary artery anomaly in both patients.
• Detailed anatomical variations were noted, including a varicose right coronary artery and critical stenoses in specific branches in the first case.
• CT angiography in the second case elucidated the retroaortic course of the left coronary artery.

Implications:

• This case series highlights the importance of considering rare coronary anomalies in patients with angina, even with normal noninvasive testing.
• Accurate anatomical delineation through advanced imaging modalities like coronary angiography and CT angiography is crucial for surgical planning.
• Coronary artery bypass grafting was the chosen surgical approach for both patients, underscoring its role in managing symptomatic single coronary artery anomalies.