Extremely rare single right coronary artery: multidetector computed tomography findings

Arteria coronaria derecha única muy infrecuente: hallazgos por tomografía computada multidetector

Mauro Echavarría–Pinto, Engels Rodríguez–Rodríguez, Enrico Macías, Eric Kimura–Hayama.

Department of Radiology. Instituto Nacional de Cardiología Ignacio Chávez. Mexico City, Mexico.

Received on September 9, 2011.
Accepted on December 9, 2011.

Coronary anomalies are rare, with a reported prevalence of 1.3% among patients who undergo coronary angiography. The great majority of coronary artery anomalies are incidental findings and are not clinically significant, but in some cases, may be responsible for angina, syncope, arrhythmias or even sudden death. In the following case, we describe coronary CT angiography findings of one of the rarest coronary anomalies. Lipton R–I type single right coronary artery has only been previously reported in very few occasions and has been seen in only 0.0007% of the population.

Keywords: Coronary anomalies; Multidetector computed tomography; Single right coronary artery; Mexico.

Resumen

Las anomalías congénitas de las arterias coronarias son raras, con una prevalencia estimada de 1.3% en pacientes sometidos a angiografía coronaria. La gran mayoría de estas anomalías no son clínicamente significativas, aunque en algunos casos, pueden producir angina, síncope, arritmias e incluso muerte súbita. En el siguiente caso, describimos mediante tomografía computarizada multicorte, una de las anomalías congénitas de las arterias coronarias más raras. La arteria coronaria derecha única tipo R–I de Lipton, de la que sólo se han reportado muy pocos casos y su prevalencia se estima en 0.0007%.

Palabras clave: Anomalías coronarias; Tomografía computada multicorte; Arteria coronaria derecha única; México.

A 68–yo woman with systemic arterial hypertension requested medical attention because of atypical chest pain. Physical examination, cardiac biomarkers and 12–lead electrocardiogram were unremarkable. A treadmill stress test showed monomorphic ventricular extrasystolia in association with atypical chest pain during early recovery phase. Finally, a coronary CT angiography performed on a 64–slice scanner, showed absence of the left coronary artery and demonstrated a single coronary artery arising from the right coronary sinus of Valsalva. The right coronary artery continued its course as a left circumflex artery and ended as a left anterior descending artery (Figures 1 and 2). This unusual case of a single coronary artery anomaly (SCA) corresponds to a Lipton R–I type.¹ No plaques were noted and the Calcium score was 0 AU. Conservative treatment was recommended and she has being doing well during a 2–year follow–up.

One of the rarest coronary artery anomalies is the SCA R–I type of which very few cases have been reported (in a very large series, only one was found in 126 595 pa–tients).^2,3 Coronary anomalies may cause reduced regional myocardial blood flow particularly in the presence of interarterial courses or vasospasm but, in the present case, no atherosclerosis was found and the coronary course was sought to be hemodynamically benign. Even though, we encourage close follow up, as obstruction of a SCA could be catastrophic. Nowadays, MDCT allows non–invasive, multiplanar and accurate assessment of coronary arteries and should be coronary anomalies diagnostic reference method.

Conflict of interest

Dr. Eric Kimura–Hayama is Advisor of the Imaging Solutions Advisory Board (ISAB) of Covidien. The rest of coauthors have no conflict of interest.

References

1. Lipton MJ, Barry WH, Obrez I, et al. Isolated single coronary artery: diagnosis, angiographic classification, and clinical significance. Radiology 1979;130: 39–47.         [ Links ]

2. Yamanaka O, Hobbs RE. Coronary artery anomalies in 126,595 patients undergoing coronary arteriography. Cathet Cardiovasc Diagn 1990;21:28–40.         [ Links ]

3. Desmet W, Vanhaecke J, Vrolix M, et al. Isolated single coronary artery: a review of 50,000 consecutive coronary angiographies. Eur Heart J 1992;13:1637–1640.         [ Links ]