Left main coronary artery originating from the non-coronary sinus: A rare low-risk coronary anomaly

Abstract is not required for Clinical Imagesis not required for Clinical Images (This page in not part of the published article.) International Journal of Case Reports and Images, Vol. 7 No. 3, March 2016. ISSN – [0976-3198] Int J Case Rep Images 2016;7(3):195–197. www.ijcasereportsandimages.com Binyousef et al. 195 CASE REPORT OPEN ACCESS Left main coronary artery originating from the noncoronary sinus: A rare low-risk coronary anomaly Razan F. Binyousef, Fahed K. Habib, Mohammed W. Althobaiti


CASE REPORT OPEN ACCESS
Left main coronary artery originating from the noncoronary sinus: A rare low-risk coronary anomaly Razan F. Binyousef, Fahed K. Habib, Mohammed W. Althobaiti

CASE REPORT
A 51-year-old female was evaluated for chest discomfort, palpitations, and worsening dyspnea on exertion. She had no relevant past medical history and the cardiac enzymes were within normal limits. She denied any history of sudden cardiac death in her family. On physical examination, she was noted to have a 1/6 systolic murmur heard over the second left inter-costal space and an electrocardiogram was normal. Transthoracic echocardiography was normal.
A contrast enhanced cardiac computed tomography angiography (CTA) was performed to further evaluate her symptoms and to investigate for a possible coronary artery disease. The computed tomography scan showed the left main coronary artery arising from the noncoronary sinus with an acute angle (LCANCS) ( Figure 1). A nuclear exercise stress test performed and was normal ( Figure 2).

DISCUSSION
Anomalies of coronary arteries encompass a diverse group of rare coronary artery variations in origin, course or termination. Numerous studies reported incidence of coronary anomalies variably between 1% and 2% [1]. The reported incidence of coronary artery anomalies in patients undergoing coronary catheterization is 1.3% [1]. A retrospective series of 2096 patient undergoing coronary CTA showed a prevalence of approximately 2% [2]. The anomalous origin of left main coronary artery from non-coronary sinus is an extremely rare anomaly with variable incidence estimated at 0.0008% [1]. To the best of our knowledge, there are only three cases of LCANCS described by CT scan [3][4][5]. Anomalous origin of the left main coronary artery from the non-coronary sinus (LCANCS) is extremely rare with few reported cases in English literature [3].  A few reported cases of LCANCS were presented by acute myocardial infarction (MI), fatal arrhythmias and sudden cardiac death (SCD). Multiple studies proposed several mechanisms for high-risk coronary anomalies; these mechanisms include acute take-off angle (if the angle measures <45° between the proximal LCA and ascending aorta), intramural course (shared intima and media between aorta and LCA), or slit like ostium (if the ridge exceeded 50% of the coronary ostial luminal area) [6]. While the mechanisms are variable, the true significance of these coronary findings is not clear [7]. Not all coronary artery anomalies are felt to increase the risk of sudden cardiac death.

CliNiCAl imAgES PEER REviEwEd | OPEN ACCESS
The symptoms related to high risk coronary anomalies are mostly experienced during vigorous exercise. Most of the symptomatic cases are reported in young patients below the age of 30 [3]. Many cases presented late in relation to development of atherosclerotic changes. In elderly, these findings are probably detected incidentally in asymptomatic candidates. If these anomalies were associated with symptoms, the question would be what should be done next. Single-photon emission computed tomography (SPECT) myocardial perfusion test is a good option. A normal myocardial SPECT would obviate the need for further investigation particularly in old patients. However, if the SPECT myocardial perfusion test is positive in the presence of coronary anomaly in symptomatic patient, this would raise the question of whether surgical intervention should be expedited. In our case, the normal SPECT myocardial perfusion study was reassuring, excluding a significant coronary compression during stress and suggests that the anomaly in our patient is a benign incidental finding.

CONCLUSION
In the present case, computed tomography angiography (CTA) identified a rare coronary anomaly and excluded the presence of obstructive atherosclerotic coronary artery disease substantiating its role as a powerful non-invasive imaging modality in the assessment of coronary arteries. Combining the functional data from nuclear stress test with anatomical data from cardiac CT scan excluded the presence of ischemia in the myocardial regions supplied by the anomalous coronary artery.

AN INTRODUCTION
Edorium Journals: On Web

About Edorium Journals
Edorium Journals is a publisher of high-quality, open access, international scholarly journals covering subjects in basic sciences and clinical specialties and subspecialties.

Edorium Journals: An introduction
Edorium Journals Team

But why should you publish with Edorium Journals?
In less than 10 words -we give you what no one does.

Vision of being the best
We have the vision of making our journals the best and the most authoritative journals in their respective specialties. We are working towards this goal every day of every week of every month of every year.

Exceptional services
We care for you, your work and your time. Our efficient, personalized and courteous services are a testimony to this.

Editorial Review
All manuscripts submitted to Edorium Journals undergo pre-processing review, first editorial review, peer review, second editorial review and finally third editorial review.

Peer Review
All manuscripts submitted to Edorium Journals undergo anonymous, double-blind, external peer review.

Early View version
Early View version of your manuscript will be published in the journal within 72 hours of final acceptance.

Manuscript status
From submission to publication of your article you will get regular updates (minimum six times) about status of your manuscripts directly in your email.

Most Favored Author program
Join this program and publish any number of articles free of charge for one to five years.

Favored Author program
One email is all it takes to become our favored author. You will not only get fee waivers but also get information and insights about scholarly publishing.

Institutional Membership program
Join our Institutional Memberships program and help scholars from your institute make their research accessible to all and save thousands of dollars in fees make their research accessible to all.

Our presence
We have some of the best designed publication formats. Our websites are very user friendly and enable you to do your work very easily with no hassle.

Something more...
We request you to have a look at our website to know more about us and our services.
We welcome you to interact with us, share with us, join us and of course publish with us.

Invitation for article submission
We sincerely invite you to submit your valuable research for publication to Edorium Journals.

Six weeks
You will get first decision on your manuscript within six weeks (42 days) of submission. If we fail to honor this by even one day, we will publish your manuscript free of charge.

Four weeks
After we receive page proofs, your manuscript will be published in the journal within four weeks (31 days). If we fail to honor this by even one day, we will publish your manuscript free of charge and refund you the full article publication charges you paid for your manuscript.