Isolated Single Coronary Artery in a Patient Presenting with an Abnormal ECG

A 45-year-old male with a history of hypertension, exertional and self-limiting chest pain, and an abnormal electrocardiogram (ECG) was referred for further evaluation. Review of his ECG showed 2-mm ST elevation in leads V2 and V3, and 1-mm ST elevation in leads V4-V6. Transthoracic echocardiography showed only mild global left ventricular (LV) hypokinesis. Subsequent coronary angiography (Figure 1) revealed a single common coronary artery (SCA) arising from the right coronary cusp with no significant obstructive disease and a dominant right coronary artery (RCA) that wrapped around the left ventricular apex. Computed tomography coronary angiography (Figures 2-5) confirmed the right coronary cusp origin. The left anterior descending coronary artery (LAD) was shown to course anterior to the pulmonary artery. The left circumflex and RCA followed a relatively normal course; the RCA was confirmed to be large and to cover an extensive part of the inferior and apical left ventricular walls.

SCA arising from the right sinus of valsalva is a very rare anomaly, accounting for 0.3%¹ of all coronary anomalies and just 0.026%-0.066%^2,3 of the general population. This anomaly is labeled R-III (A) by the modified¹ Lipton classification system.³ Although associated with exertional chest pain, this anomaly does not have an intra-arterial course and therefore is thought to not be associated with compression between the great arteries, myocardial infarction, or sudden death.⁴

The authors can be contacted via Ihab Alomari, MD, at ialomari@salud.unm.edu.

References

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