Overview of coronary artery variants, aberrations and anomalies

Coronary artery anomalies and variants are relatively uncommon congenital disorders of the coronary artery anatomy and constitute the second most common cause of sudden cardiac death in young competitive athletes. The rapid advancement of imaging techniques, including computed tomography, magnetic resonance imaging, intravascular ultrasound and optical coherence tomography, have provided us with a wealth of new information on the subject. Anomalous origin of a coronary artery from the contralateral sinus is the anomaly most frequently associated with sudden cardiac death, in particular if the anomalous coronary artery has a course between the aorta and the pulmonary artery. However, other coronary anomalies, like anomalous origin of the left coronary artery from the pulmonary artery, atresia of the left main stem and coronary fistulae, have also been implicated in cases of sudden cardiac death. Patients are usually asymptomatic, and in most of the cases, coronary anomalies are discovered incidentally during coronary angiography or on autopsy following sudden cardiac death. However, in some cases, symptoms like angina, syncope, heart failure and myocardial infarction may occur. The aims of this article are to present a brief overview of the diverse coronary variants and anomalies, focusing especially on anatomical features, clinical manifestations, risk of sudden cardiac death and pathophysiologic mechanism of symptoms, as well as to provide valuable information regarding diagnostic workup, follow-up, therapeutic choices and timing of surgical treatment.

A study of coronary artery variants and anomalies observed at a tertiary care armed forces hospital using 64-slice MDCT

BACKGROUND

Isolated coronary artery anomalies are usually clinically silent and mostly detected incidentally during angiography or autopsy. However, few of them may be implicated in cases of sudden cardiac death even in the absence of additional heart abnormalities. Prior knowledge of such variants and anomalies is necessary for planning various interventional procedures. Multiple detector computed tomography coronary angiography has proved a very useful non-invasive modality in this field given its superiority over conventional coronary angiography in providing detailed coronary artery anatomy.

METHODS

A retrospective review of the coronary CT angiography studies was carried out at our center between August 2014 and December 2015 with the purpose of describing the coronary artery variants and anomalies that we came across in our cohort.

RESULTS

In our cohort, about 77% (n=391) of the patients had a right dominant system while left dominant and co-dominant systems were seen in 12% (n=61) and 11% (n=56) respectively. Coronary CT angiography was successful in visualizing smaller branches, such as the conus artery (96.25%, n=489), the sinus node artery (83.07%, n=422), and the septal branches (95.27%, n=484). Coronary anomalies were observed in the 10.04% of our population (n=51). Eleven anomalies of origin and course were found.

CONCLUSION

Coronary CT angiography gives us a good understanding of the variations and anomalies of the anatomy of the coronary arteries. This can be of immense help to the clinician planning interventional procedures.