Anomalous Origin Of The Left Circumflex Coronary Artery From Right Coronary Sinus.

Case history:
A 43-year-old female patient with hypertension, diabetes mellitus and dyslipidemia presented with non-specific chest pain that had lasted for five days. No previous history of CAD. Her physical examination, troponin levels, echocardiogram and electrocardiogram were normal. She has a strong family history of CAD. CT coronary angiography was advised for further evaluation.

Findings:
CT coronary angiography shows:

  •  Left dominant coronary circulation
  • Anomalous origin of left circumflex (LCX) artery is seen from right coronary sinus with separate ostium for both LCX and RCA. LCX courses postero-inferior to the aortic root to re-enter anterior atrioventricular groove (Figure 1,2).
  • Left main coronary artery (LMCA) continues as left anterior descending artery (LAD).
  • No stenosis in coronary arteries.

Discussion:

The origin of the LCX from the right sinus of Valsalva is a well-known anatomical variation (1,2). The clinical significance of the anomaly is obvious in patients undergoing PCI or cardiac surgery (3).
According to some publications, anomalous LCx is divided into 3 types (4).

  • type I: separate ostia for right coronary artery (RCA) and LCx.
  • type II: common ostia in the right sinus.
  • type III: LCx arising as a branch of the proximal RCA.

An aberrant but normal LCX arising from the right coronary sinus (common or separate ostium with the RCA) has no clinical significance per se, and it does not predispose the LCX to a higher incidence of obstructive disease (5).

References:

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