Superdominant Circumflex Thrombosis With Occluded LAD and Absent RCA Ostium

J INVASIVE CARDIOL 2019;31(2):E45.

Key words: cardiac imaging, coronary anomaly, PCI

An 80-year-old male patient with a history of hypertension, hypothyroidism, and previous smoking presented at the emergency department due to chest pain that started 5 hours prior to admission.

Clinical examination revealed pulmonary basal rales, with no other relevant findings. Electrocardiogram showed sinus rhythm and inferior, lateral, and posterior ST-segment elevation. Bolus doses of aspirin and clopidogrel were administered and the patient was submitted to emergency cardiac catheterization.  

Coronary angiography showed a large, dominant left circumflex (LCX) artery with subocclusive thrombus burden (Figure 1A). The left anterior descending (LAD) artery was chronically occluded in the proximal segment, and the right coronary artery ostium was absent despite several attempts to locate it at the right coronary sinus and at different sites of possible anatomic variations (Figure 1B). Primary percutaneous coronary intervention (PCI) was successfully performed in the proximal and mid segments of the LCX with two drug-eluting stents. After restoration of normal flow, angiography clarified a superdominant LCX with extended course through the left atrioventricular groove and right coronary topography, supplying the right ventricular and atrial branches (Figure 1C). Intracoronary collaterals to the distal LAD were noted arising from the distal LCX. The patient recovered well after the procedure without major complications, but developed severe left ventricular dysfunction with an ejection fraction of 26% by transthoracic echocardiogram.

To our knowledge, this is the first report of primary PCI in a patient with a superdominant LCX, in which the entire RCA myocardium territory was provided by the LCX. Single coronary arteries are among the most rare anatomic coronary anomalies, and the absence of RCA ostium has been described as the rarest of these anomalies. Coronary events in such cases can be catastrophic due to the large amount of myocardium at risk.

From the Division of Cardiology, Hospital de Clínicas de Porto Alegre, Brazil.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors report no conflicts of interest regarding the content herein.

The authors report that patient consent was provided for publication of the images used herein.

Manuscript accepted September 17, 2018.

Address for correspondence: Gustavo Neves de Araujo, MD, PhD, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Brazil. Email: gustavon.araujo@gmail.com