The Single Coronary Artery: A Rare Anatomic Variant

A 67-year-old female presented to the emergency department with complaints of progressively worsening shortness of breath, orthopnea, and decreased exercise tolerance for a duration of 3 days. The patient described this as her first episode of dyspnea and denied associated chest pain, palpitations, diaphoresis, headache, or gastrointestinal symptoms.

She endorsed a 30 pack-year history of smoking, regular marijuana use, and occasional alcohol consumption. She had no prior surgical history or known family history of premature coronary artery disease or sudden cardiac death.

Transthoracic echocardiography indicated grade 2 diastolic dysfunction and raised filling pressures consistent with heart failure with reduced ejection fraction. Cardiac catheterization revealed pulmonary hypertension, left ventricular dilation, and an ejection fraction of 30% to 35%.

Coronary angiography delineated uncommon coronary anatomy in which all major coronary arteries originated from a common ostium within the right aortic sinus. The right coronary artery courses along the right atrioventricular groove, while the anomalous left anterior descending and left circumflex arteries crossed from their origin to their respective areas of distribution (Figures 1, 2). The posterior descending artery was found to have a 25% stenosis. Proximal RCA had mild atherosclerosis.

Figure 1

Figure 2

The patient was initiated on guideline-directed pharmacological therapy and was subsequently discharged after a 5-day hospitalization with computed tomography angiography (Figure 3) on follow-up.

Figure 3