Superdominant left circumflex with absence of the right coronary artery: an interesting and very rare coronary anomaly
Case Report

Superdominant left circumflex with absence of the right coronary artery: an interesting and very rare coronary anomaly

Marcos Danillo Peixoto Oliveira1,2, Ednelson Cunha Navarro2, Thiago Ximenes Ferraz1, Fabio Santos Silveira1, Glenda Alves de Sá2, Helio Jose Castello Júnior2, Marcelo José de Carvalho Cantarelli2

1Faculty of Medicine, University of Taubaté (UNITAU), Taubaté, São Paulo, Brazil; 2Department of Interventional Cardiology, Hospital Regional do Vale do Paraíba, Taubaté, São Paulo, Brazil

Correspondence to: Marcos Danillo Peixoto Oliveira. Department of Interventional Cardiology, Hospital Regional do Vale do Paraíba, Avenida Tiradentes, 280, Jardim das Nações, Taubaté, São Paulo, Brazil. Email: mdmarcosdanillo@gmail.com.

Abstract: Coronary artery anomalies (CAA) are congenital changes in their origin, course and/or structure. Most of them are discovered as incidental findings during coronary angiographic studies or autopsies. A vessel is considered superdominant when it supplies the myocardium normally perfused by the other vessel. The occurrence of a superdominant left circumflex (LCx) artery supplying the territory of the right coronary artery (RCA) is extremely rare. We present the case of a 64-year-old woman complaining of stable angina at moderate efforts, with a positive treadmill test, referred to angiography, which incidentally revealed a very rare and interesting coronary anomaly circulation pattern.

Keywords: Coronary artery anomalies (CAA); superdominant left circumflex; coronary angiography


Received: 02 November 2018; Accepted: 16 November 2018; Published: 11 December 2018.

doi: 10.21037/jxym.2018.11.02


Coronary artery anomalies (CAA) are a diverse group of congenital disorders, and the pathophysiological mechanisms and manifestations are highly variable. Several controversies remain in terms of its incidence, classification, screening, heredity and treatment. Most of them are discovered as incidental findings during coronary angiographic studies or at autopsies (1-3).

A vessel is considered superdominant when it supplies the myocardium normally perfused by the other vessel (4). The occurrence of a superdominant LCx artery supplying the territory of the RCA is an extremely rare phenomenon (4,5). It has also been described in the literature as anomalous RCA originating from the LCx.

A 74-year-old woman complaining of stable angina at moderate efforts, with a positive treadmill test was then referred to elective coronary angiography. The LCx showed a superdominant pattern, with various obtuse marginal, posterior descending and posterolateral branches, extending beyond the crux cordis, circling the atrioventricular groove, following the expected path of the absent RCA (Figures 1-6). Aortograms and non-selective injections of contrast media into the right coronary sinus showed no emergent arteries, confirming the congenital absence of the RCA (Figure 7). There was noted a marked stenosis at the ostium and the proximal portion of a large inferior branch of the second obtuse marginal, which was successfully treated with the deployment of a drug-eluting stent.

Figure 1 The superdominant LCx, with various obtuse marginal, posterior descending and posterolateral branches, extending beyond the crux cordis, circling the atrioventricular groove, following the expected path of the absent RCA. Anteroposterior caudal view. LCx, left circumflex; RCA, right coronary artery.
Figure 2 The superdominant LCx, with various obtuse marginal, posterior descending and posterolateral branches, extending beyond the crux cordis, circling the atrioventricular groove, following the expected path of the absent RCA. Cranial left anterior oblique view. LCx, left circumflex; RCA, right coronary artery.
Figure 3 The superdominant LCx, with various obtuse marginal, posterior descending and posterolateral branches, extending beyond the crux cordis, circling the atrioventricular groove, following the expected path of the absent RCA. Cranial right anterior oblique view. LCx, left circumflex; RCA, right coronary artery.
Figure 4 The superdominant LCx, with various obtuse marginal, posterior descending and posterolateral branches, extending beyond the crux cordis, circling the atrioventricular groove, following the expected path of the absent RCA. Anteroposterior caudal view (6). LCx, left circumflex; RCA, right coronary artery. Available online: http://www.asvide.com/article/view/28800
Figure 5 The superdominant LCx, with various obtuse marginal, posterior descending and posterolateral branches, extending beyond the crux cordis, circling the atrioventricular groove, following the expected path of the absent RCA. Left anterior oblique caudal (“spider”) view (7). LCx, left circumflex; RCA, right coronary artery. Available online: http://www.asvide.com/article/view/28801
Figure 6 The superdominant LCx, with various obtuse marginal, posterior descending and posterolateral branches, extending beyond the crux cordis, circling the atrioventricular groove, following the expected path of the absent RCA. Cranial left anterior oblique view (8). LCx, left circumflex; RCA, right coronary artery. Available online: http://www.asvide.com/article/view/28802
Figure 7 Aortograms and non-selective injections of contrast media into the right coronary sinus showing no emergent arteries, confirming the congenital absence of the RCA. RCA, right coronary artery.

The multi-detector row computed tomography (MDCT) coronary angiography allows accurate and noninvasive depiction of CAA. Unfortunately, due to public health system limitations, this patient was referred to the invasive angiography instead of the MDCT.

The non-visualization of the RCA from the right coronary sinus in the setting of acute coronary syndromes can be mistaken for an ostial RCA occlusion. Any attempt at revascularization may result in inadvertent injury (e.g., perforation of the coronary sinus by forceful manipulation of the guidewire).

All interventional cardiologists and cardiac surgeons should be familiar with these anatomic variants since accurate recognition of the course and distribution of the coronary vessels is crucial for proper revascularization strategies in the presence of coronary artery disease.


Acknowledgements

None.


Footnote

Conflicts of Interest: The authors have no conflicts of interest to declare.

Informed Consent: Written informed consent was obtained from the patient for publication of this manuscript and any accompanying images.


References

  1. Angelini P. Coronary Artery Anomalies: An Entity in Search of an Identity. Circulation 2007;115:1296-305. [Crossref] [PubMed]
  2. Oliveira MD, de Fazzio FR, Mariani J Junior, et al. Superdominant Right Coronary Artery with Absence of Left Circumflex and Anomalous Origin of the Left Anterior Descending Coronary from the Right Sinus: An Unheard Coronary Anomaly Circulation. Case Rep Cardiol 2015;2015:721536. [Crossref] [PubMed]
  3. Almeida C, Dourado R, Machado C, et al. Anomalias das artérias coronárias. Rev Port Cardiol 2012;31:477-84. [Crossref] [PubMed]
  4. Yamanaka O, Hobbs RE. Coronary artery anomalies in 125,595 patients undergoing coronary angiography. Cathet Cardiovasc Diagn 1990;21:28-40. [Crossref] [PubMed]
  5. Agrawal N. Superdominant left-circumflex artery supplying significant proportion of RCA and LAD territory. BMJ Case Rep 2015;2015.
  6. Oliveira MD, Navarro EC, Ferraz TX, et al. The superdominant LCx, with various obtuse marginal, posterior descending and posterolateral branches, extending beyond the crux cordis, circling the atrioventricular groove, following the expected path of the absent RCA. Anteroposterior caudal view. Asvide 2018;5:903. Available online: http://www.asvide.com/article/view/28800
  7. Oliveira MD, Navarro EC, Ferraz TX, et al. The superdominant LCx, with various obtuse marginal, posterior descending and posterolateral branches, extending beyond the crux cordis, circling the atrioventricular groove, following the expected path of the absent RCA. Left anterior oblique caudal (“spider”) view. Asvide 2018;5:904. Available online: http://www.asvide.com/article/view/28801
  8. Oliveira MD, Navarro EC, Ferraz TX, et al. The superdominant LCx, with various obtuse marginal, posterior descending and posterolateral branches, extending beyond the crux cordis, circling the atrioventricular groove, following the expected path of the absent RCA. Cranial left anterior oblique view. Asvide 2018;5:905. Available online: http://www.asvide.com/article/view/28802
doi: 10.21037/jxym.2018.11.02
Cite this article as: Oliveira MD, Navarro EC, Ferraz TX, Silveira FS, de Sá GA, Castello Júnior HJ, Cantarelli MJ. Superdominant left circumflex with absence of the right coronary artery: an interesting and very rare coronary anomaly. J Xiangya Med 2018;3:42.