Discussion
Anomalous origin of the right coronary artery is a rare congenital anomaly that was 1st described in 1948 by White and Edwards7 .The prevalence of this anomaly in the white population, as determined from autopsy studies, is 0.026%.8The prevalence of this anomaly in patients undergoing coronary angiography was0.25% 9-10 .
It is well established that an anomalous origin of the right coronary artery can lead to angina pectoris, myocardial infarction, or sudden death, in the absence of atherosclerosis11. The pathophysiologic basis for this association, however, is unclear. Mechanical compression of the right coronary artery by the great vessels is the usual explanation, because the anomalous right coronary artery generally courses between the aorta and the pulmonary artery to its normal position. Others have suggested that the oblique angle at the juncture of the anomalous right coronary artery and the left coronary sinus produces a slit-like orifice in the aortic wall that can collapse during exercise11 Recently, Kaku’s group12 suggested that the proximal portion of the right coronary artery, situated between the aorta and the pulmonary artery, might be more prone to spasm than it would be otherwise.
Regardless of the causes of the adverse associations, there is a need to study prospectively those patients at highest risk. Moreover, the anomalous right coronary artery was 2nd only to the anomalous left main coronary artery as the cardiac anomaly ,most frequently associated with sudden cardiac death.
In an effort to stratify such cases by risk, Taylor and associates later (in 1997)13performed a blinded pathologic analysis of 21 cases of anomalous origin of the right coronary artery. Despite reviewing a variety of anatomic variables (including ostial size, length of intramural course, angle of takeoff, and the presence of symptoms), this group found that only an age of 30 years or older was associated with a lower incidence of sudden cardiac death.
Understandably, the choice of treatment for this coronary anomaly is controversial, with some advocating revascularization in all cases. Proposed options include translocation of the right coronary artery to the aorta,14ostioplasty (excision of the common wall between the right coronary artery and the aorta),15and bypass grafting of the right coronary artery (with optional ligation of the native artery proximal to the graft anastomosis to prevent competitive flow)16.However, the long-term benefits of such therapies have not yet been demonstrated.
In Japan, treatment for this condition is more conservative. Kaku and associates17studied 56 patients with an anomalous origin of a coronary artery and treated them medically with β-blockers. Approximately 9% of these patients experienced episodes of hypotension and arrhythmias on exertion, and no death was found to be directly related to the congenital anomaly during 5 years of follow-up.
With the available data, it would be good idea to subject them for illicitable ischemia . Any evidence of the risk factors such as oblique course, slit like opening and long abnormal course should err towards re-translocation. Otherwise, close monitoring with frequent evaluation for ilicitable ischemia as in our case may be a good alternative. Efforts can give rise to the large-scale studies needed to define the prognosis and optimal treatment of individual forms of coronary artery abnormality.
Conclusion :-Coronary artery anomalies should be regarded as an uneven diverse group of congenital disorders whose manifestations and pathophysiological mechanisms are highly variable. This is a case report of rare coronary artery anomaly with interarterial course, without evidence of ischemic sign, in otherwise asymptomatic young boy. Watchful observation and strenuous activity restriction was applied in our case.
Reference:-
1. Ouali S, Neffeti E, Sendid K, et al: Congenital anomalous aortic origins of the coronary arteries
in adults: A Tunisian coronary arteriography study. Arch Cardiovasc Dis 102:201, 2009.
2. Baskurt M, Yyldyz A, Caglar IM, et al: Right coronary artery arising from the pulmonary
trunk. ThoracCardiovascSurg 57:424, 2009
3. Eckart RE, Jones SO, Shry EA, et al: Sudden death associated with anomalous coronary origin and obstructive coronary disease in the young. Cardiol Rev 14:161, 2006.
4. von Kodolitsch Y, Franzen O, Lund GK, et al: Coronary artery anomalies. Part II: recent
insights from clinical investigations. Z Kardiol 94:1, 2005.
5. Opolski MP, Pregowski J, Kruk M, et al: Prevalence and characteristics of coronary anoma-lies originating from the opposite sinus of Valsalva in 8,522 patients referred for coronary
computed tomography angiography. Am J Cardiol 111:1361, 2013
6. John S. Ho, MD and Neil E. Strickman, Anomalous Origin of the Right Coronary Artery from the Left Coronary Sinus, Tex Heart Inst J. 2002; 29(1): 37–39.
7. White NK, Edwards JE. Anomalies of the coronary arteries.Report of four cases. Arch Pathol 1948;45:766–71. [PubMed]
8. Alexander RW, Griffiths GC.Anomalies of the coronary arteries and their clinical significance. Circulation 1956;14: 800–5. [PubMed]
9. Kaku B, Shimizu M, Yoshio H, Ino H, Mizuno S, Kanaya H, et al. Clinical features of prognosis of Japanese patients with anomalous origin of the coronary artery. JpnCirc J 1996;60:731–41. [PubMed]
10. Topaz O, DeMarchena EJ, Perin E, Sommer LS, Mallon SM, Chahine RA. Anomalous coronary arteries: angiographic findings in 80 patients. Int J Cardiol 1992;34:129–38. [PubMed]
11. Taylor AJ, Rogan KM, Virmani R. Sudden cardiac death associated with isolated congenital coronary artery anomalies. J Am CollCardiol 1992;20:640–7. [PubMed]
12. Kaku B, Kanaya H, Ikeda M, Uno Y, Fujita S, Kato F, Oka T. Acute inferior myocardial infarction and coronary spasm in a patient with an anomalous origin of the right coronary artery from the left sinus of Valsalva. JpnCirc J 2000;64: 641–3
13. Taylor AJ, Byers JP, Cheitlin MD, Virmani R. Anomalous right or left coronary artery from the contralateral coronary sinus: “high-risk” abnormalities in the initial coronary artery course and heterogeneous clinical outcomes. Am Heart J 1997;133:428–35.
14. Di Lello F, Mnuk JF, Flemma RJ, Mullen DC.Successful coronary reimplantation for anomalous origin of the right coronary artery from the left sinus of Valsalva. J ThoracCardiovascSurg 1991;102:455–6. [PubMed]
15. Rinaldi RG, Carballido J, Giles R, Del Toro E, Porro R. Right coronary artery with anomalous origin and slit ostium. Ann ThoracSurg 1994;58:829–32. [PubMed]
16. Shah AS, Milano CA, Lucke JP. Anomalous origin of the right coronary artery from the left coronary sinus: case report and review of surgical treatments. CardiovascSurg 2000;8:284–6. [PubMed]
17. Kaku B, Shimizu M, Yoshio H, Ino H, Mizuno S, Kanaya H, et al. Clinical features of prognosis of Japanese patients with anomalous origin of the coronary artery. JpnCirc J 1996;60:731–41.
Legends:-
Figure 1: 12 lead ECG in the patient with abnormal right coronary artery from left sinus, showing no evidence of ischemia.
Figure 2: Parasternal short axis view showing the origin of right coronary artery from left sinus (marked by arrow). Ao: aorta, PA: pulmonary artery
Figure 3: CT coronary angiogram showing anomalous origin of right coronary artery from the anomalous sinus (marked by arrow). The original expected position of the coronary artery is marked by the star. Ao: aorta, RCA: right coronary artery.