High-Takeoff Anomalous Right Coronary Artery Arising From The Ascending Aorta: A Case Report

Background Anomalous origin of the coronary arteries is an uncommon congenital abnormality that may pose diagnostic challenges during invasive coronary angiography. High-takeoff origin of the right coronary artery (RCA) from the ascending aorta is particularly rare and can mimic ostial occlusion, potentially leading to prolonged procedures and inappropriate catheter manipulation. Computed tomography coronary angiography (CTCA) plays a crucial role in accurately defining the anatomical origin and course of anomalous coronary arteries and in guiding management. Case presentation A 70-year-old woman with diabetes mellitus, hypertension, hypothyroidism, and known mitral valve prolapse presented with intermittent palpitations. Electrocardiography revealed frequent ventricular premature complexes, and 24-hour Holter monitoring documented 9,259 premature ventricular complexes. Transthoracic echocardiography showed preserved biventricular systolic function with mild-to-moderate mitral regurgitation. Coronary angiography performed via the right radial artery demonstrated normal left coronary arteries but difficulty in engaging the RCA in its expected location. After systematic angiographic exploration using alternative catheter strategies, the RCA was selectively engaged from a slit-like ostium located above the left coronary cusp. CT coronary angiography confirmed anomalous origin of the RCA from the anterior and left lateral wall of the ascending aorta, 20.9 mm above the sino-tubular junction, with a short interarterial course measuring 1.9 cm and no luminal narrowing or compression. The patient was managed conservatively and remained clinically stable. Conclusions High-takeoff anomalous origin of the RCA from the ascending aorta is a rare but important diagnostic consideration when selective coronary engagement is challenging. Early recognition and use of CT coronary angiography are essential for accurate diagnosis and risk stratification.