Right Coronary Artery With Anomalous Origin and Slit Ostium

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1 Right Coronary Artery With Anomalous Origin and Slit Ostium Raul Garcia Rinaldi, MO, Jorge Carballido, MO, Richard Giles, MO, Emilio Del Taro, MO, and Raul Porro, MO Departments of Cardiovascular Surgery and Anesthesia of the Cardiovascular Institute, Pavia Hospital, and the Cardiovascular Institute, San Lucas Hospital, San Juan, Puerto Rico Right coronary arteries that arise from the left sinus or ectopically from the right sinus with a slit ostium can cause myocardial ischemia, myocardial infarction, or sudden death. The surgical repair of these anomalies has evolved toward a simpler operation that widens the orifice of ongm and reduces the compression of the intramural segment. We have repaired these anomalies without mortality in 8 patients. We summarize our experience and the evolution of this procedure. (Ann Thorae Surg 1994;58:828-32) Right coronary arteries that arise from the left sinus in an anomalous manner have been classified by Kragel and Roberts [1] into four types. These types are defined in Table 1 and are depicted in Figure 1. In addition, Virmani [2,3] and Isner [4] and their associates have observed that right coronary arteries which arise ectopically in the right sinus behave in the same manner as those that arise anomalously from the left sinus when the ostium has a valve ridge (ie, slit). Both groups of anomalies produce myocardial ischemia and infarction, and their sequelae [3-6]. Although the mechanism responsible for causing the ischemia is still unclear, the slit ostium and the acute angle from which the right coronary artery takes off, which are invariably found in both groups of anomalies, seem to be causes [2-6]. Cheitlin and colleagues [7] were the first to describe the influence of a slit ostium with a valve-type ridge in terms of the morbidity and mortality associated with anomalous coronary arteries. Other mechanisms implicated as causes of myocardial ischemia when the right coronary artery arises from the left sinus are stretching of the aortic intramural segment and compression of this segment by the aortic valve commissure, particularly during diastole [8]. This last mechanism would, of course, not apply to right coronary arteries that arise ectopically from the right sinus because they do not course under the aortic valve commissure. The treatment for right coronary arteries that arise from the left sinus has varied. Approaches have included no treatment, unless the patient is extremely symptomatic [9]; coronary artery bypass grafting using the saphenous vein [9, 10] or the internal mammary artery [8]; reimplantation into the correct sinus from outside the aorta [9, 11]; and modification of the orifice of the anomalous coronary artery at the aorta by excising the common wall (septum) between the aorta and right coronary artery [12]. The Accepted for publication jan 27, Address reprint requests to Dr Garcia Rinaldi, Box 19868, Fernandez juncos Station, San juan, Puerto Rico by The Society of Thoracic Surgeons ever-increasing evidence that this anomaly is potentially lethal has prompted many authors to recommend that these lesions be treated surgically whenever they are diagnosed [13]. We report our experience with the surgical treatment of right coronary arteries with a slit ostium that arise from the left sinus or ectopically from the right sinus. At first we performed coronary artery bypass grafting in those patients with occlusive disease of the right coronary artery by grafting it with the right internal mammary artery [8], and we carried out reimplantation from outside the aorta into the right sinus in those patients with normal coronary arteries [9, 11]. More recently we have used a technique in which we modify the ostium at the aorta by excising the common wall (septum) located between the aorta and the right coronary artery [12]. This technique is based on Mustafa and associates' [13] operation for the repair of left coronary arteries that arise from the right (anterior) sinus. Because of its simplicity, we recommend use of this operation, which modifies the orifice by restoring it to a "normal" size and corrects the angulation of the takeoff. Patient Population We reviewed the hospital charts for 8 patients whose right coronary artery either arose ectopically from the right sinus and had a slit ostium or arose anomalously from the left sinus. These patients were seen between June 1989 and June The patients consisted of 6 men and 2 women who ranged in age from 28 to 55 years (average, 45.5 years). Seven patients (87.5%) had sustained a previous myocardial infarction and all had angina pectoris. Treadmill tests performed in 7 patients yielded negative results in 4 and positive results in 3. The ejection fraction ranged from 0040 to 0.60 (average, 0.50). Findings from cardiac catheterization and coronary angiography confirmed the diagnosis in all patients. Repeat /94/$7.00

2 Ann Thorac Surg 1994;58: RINALDI ET AL 829 Table 1. Classification of Right Coronary Arteries Arising Anomalously" Type 2A 2B 2C 2D Origin of Right Coronary Artery From behind the left sinus From the left sinus From above the left commissure From a common ostium with the left main coronary artery straddling the left coronary sinus and right-left commissure a Classification scheme proposed by Kragel and Roberts [11. catheterization performed by a second cardiologist was required to establish the diagnosis in 3 patients because the right coronary artery could not be identified in the first study. In addition, considerable arteriosclerosis was found in the anomalous right coronary artery in 1 patient and in the circumflex coronary artery in 2 other patients. The ages of these 3 patients were 47, 52, and 55 years. The first operations in this series were performed in 2 patients who had a true anomalous origin of the right coronary artery from the left sinus (types 2A and 2C). The artery was reimplanted from outside the aorta by detaching the ostium and reimplantating it in the right sinus. One of these patients required an aortoplasty using a Dacron patch to prevent distortion of the aorta (Fig 2). This patient also required bypass grafting of the left internal mammary artery to the first obtuse marginal coronary artery. In both cases the operation proceeded without difficulty until preparations were made to close the sternum. Acute right ventricular dilation then developed in both patients and both sustained a cardiac arrest. Cardiopulmonary bypass was instituted rapidly, the saphenous vein was used as a graft between the aorta and the right coronary artery, and both patients were weaned from the bypass without difficulty. No complications developed in 1 patient; the other was comatose for 1 week but recovered without neurologic deficits. Both patients survived and are asymptomatic at 31 and 21 months after operation, respectively. Remodeling of the slit orifice of the right coronary artery was performed in 1 patient with a type 2A anomalous origin from the left sinus, in 1 patient with a type 2C anomaly, and in 3 patients with an ectopic ostium in the right sinus. To widen the orifice in the first patient, whose artery arose from the left sinus, it was necessary to detach and resuspend the aortic valve (Fig 3). Right coronary arteries that arose ectopically from the right sinus did not require detachment and resuspension of the aortic valve (Fig 4). All 5 patients underwent remodeling of the coronary orifice from inside the aorta; they survived the operation with no complications and are completely asymptomatic as of the time of this report. One patient, who sustained a myocardial infarction but whose anomaly was not found at his first catheterization, had an 80% stenosis of the proximal portion of the anomalous right coronary artery that arose in the left sinus. This patient was treated by a free graft of the right internal artery mammary artery to the right coronary artery. He has done well postoperatively and remains asymptomatic; repeat coronary angiography performed recently demonstrated patency of the graft (Fig 5). Comment Patients who have right coronary arteries that arise in an anomalous fashion from the left sinus can suffer syncope, cardiac arrhythmias, and myocardial ischemia and infarction [1-6, 8, 12]. Similarly, if they have a slitlike ostium and the takeoff of the artery is at an extremely acute angle, right coronary arteries that arise ectopically from the right sinus can cause severe myocardial ischemia [2-5]. The ischemia in both conditions is thought to be caused by the abnormally small slitlike ostium and by the increased acuteness of the angle of origin. Stretching of the intramural segment and compression of the anomalous artery by the aortic valve commissure could occur in right coronary arteries that arise from the left sinus. We have observed that remodeling the orifice widens a I-mm ostial slit to 4 to 5 mm. The change in the geometry of the orifice is achieved along the intramural segment, thereby preventing the possible compression of the coro- RCA c. R L.. z- < ~ LMCA ) B. D. ~ R C ~ ~ : ' LMCAI \\ Fig 1. Anomalous origin of right coronary artery (RCA) from the left sinus. Site of origin from (A) behind the left sinus (type 2A in the classification of Kragel and Roberts [1]); (8) the left sinus (type 28); (C) above the left commissure (type 2C); and (0) a common ostium with the left main coronary artery (LMCA) straddling the left coronary sinus and the rightleft commissure (type 20). "

3 830 RINALDI ET AL Ann Thorac Surg arose from the right sinus. We detached the left coronary orifice from the right sinus in this patient, shortened it, and reimplanted it into the left sinus. She has done well for 5 left ostium A 7-0 polypropylene Preciotted woven Dacron patch Fig 2. Reimplaniaiion of the anomalous right coronary artery from outside the aorta. (A-C) The anomalous coronary artery is detached from the left sinus as a Carell patch. (D) An opening is made in the right coronary sinus. (E) The coronary artery is anastomosed with 7-0 sutures. (F) A woven Dacron patch is applied to prevent distortion of the aorta and aortic valve. c nary artery exerted by the stretching of the intramural segment, and thus the ischemia this may produce. Conversion of the slitlike orifice to a normal-sized opening has been sufficient to eliminate the ischemia in all our patients who have undergone this treatment. As introduced by Nelson-Piercy and colleagues [12], this method of treatment is conceptually identical to that proposed by Mustafa's group [13]. To eradicate the problem of ischemia produced by anomalous left coronary arteries that arise from the right sinus, Mustafa and co-workers modified the slit orifice of the anomalous left coronary artery from within the aorta. Evidence that these patients are susceptible to myocardial ischemia and its complications continues to grow [13]. Because of the simplicity of the operation that we have performed, surgical repair of the anatomic problem is probably warranted. In our first 2 patients, we attempted to reimplant the anomalous right coronary artery from outside the aorta [9, 11]. We used this approach because of our prior success with reimplantation in a patient whose left coronary artery Fig 3. (A) Anomalous origin of the right coronary artery from the true left sinus (type 2A). (B) The aortic valve is detached. (C) The slit ostium is incised. A portion of the common wall (septum) between the aorta and right coronary artery is excised. (D) After completion of the incision, the intimal surfaces of the aorta and right coronary artery are approximated with 7-0 sutures. (E) The aortic valve is resuspended with a 4-0 suture over a pledget, avoiding narrowing of the newly created orifice. A 4-mm dilator can be easily introduced into the orifice.

4 Ann Thorae Surg RINALDI ET AL 831 A B Left ostium c the size of the ostium is normal but its site of origin is anomalous, simple reimplantation from outside the aorta may be acceptable. This probably explains the success reported by Fernandez [9] and Oi Lello [11] and their co-workers. The reconstruction in both patients treated by reimplantation from the outside probably failed because a kink formed in the right coronary artery when the right heart filled. As already described, both patients required emergency saphenous vein grafting to save their lives. However, because most patients who require this treatment are young, we do not consider venous grafting a good alternative because of the likelihood of graft occlusion. The patients who underwent saphenous venous grafting continue to be asymptomatic 37 and 27 months postoperatively, and their stress test findings are normal. We reserve internal mammary artery grafting for those patients who have coronary artery disease of the proximal right coronary artery [14] because of our unsatisfactory experience in a patient whose left coronary artery arose anomalously from the right sinus. In this patient we placed a left internal mammary graft to the left anterior descending coronary artery. After several months, during which the patient was asymptomatic, the left internal mammary artery, which had shown excellent flow at the time of repair, became occluded. This problem may have resulted from competitive flow, that is, the preferential flow along the native left anterior descending coronary artery. The method of mobilizing the right internal mammary artery is not an issue, because all methods are known to be equally effective in the usual coronary revascularization. Fig 4. (A) Ectopic origin of the right coronary artery in the right sinus with a slit ostium. (8) The slit origin is identified and the course of the artery through the intramural segment is ascertained. (C) A portion of the common wall (septum) is excised and the incision is lengthened. (0, E) The intimal surfaces of the aorta and right coronary artery are approximated with 7-0 sutures. E years. At the time we performed this operation, we were not aware of Mustafa and colleagues' [13] simple technique. We were also not aware of the impact of the slit ostium on the postoperative results if it is not modified. If Fig 5. Anomalous origin of the rigm coronary artery from the left sinus with complex atherosclerotic narrowing. The patient underwent placement of a free graft of the right internal mammary artery to the right coronary artery. The lesion and the excellent appearance of the graft can be seen.

5 832 RINALDI ET AL Ann Thorac Surg We advocate applying the principle of Mustafa and colleagues' [13] modification of the slit orifice in those patients with left coronary arteries arising from the right sinus and in those with anomalous right coronary arteries, as performed by Nelson-Piercy and associates [12]. All 5 patients whose right coronary arteries arose either in the left sinus or ectopically with a slit orifice in the right sinus whom we treated with this technique have remained asymptomatic. None have consented to recatheterization. We believe that modifying the orifice from inside the aorta is highly effective because it widens the orifice and prevents compression of the intramural segment, thereby eliminating what seem to be the two principal causes of myocardial ischemia in these conditions. We are indebted to Lynn M. Alperin for her editorial assistance in preparing the manuscript. References 1. Kragel AH, Roberts We. Anomalous origin of either the right or left main coronary artery from the aorta with subsequent coursing between aorta and pulmonary trunk: analysis of 32 necropsy cases. Am J Cardiol 1988;62: Virmani R, Chun PKC, Goldstein RE, McAllister HA. Acute take-offs of the coronary arteries along the aortic wall and congenital ostial valve ridges: a case of sudden death [Abstract]. Circulation 1982;66(Suppl 2): Virmani R, Chun PKC, Goldstein RE, Rabinowitz M, McAllister HA. Acute take-offs of the coronary arteries along the aortic wall and congenital coronary ostial ridges: association with sudden death. J Am Coli Cardiol 1984;3: Isner JM, Shen EM, Martin ET. Sudden unexpected death as a result of anomalous origin of the right coronary artery from the left sinus of Valsalva. Am J Med 1984;76: Ness MI, McManus BM. Anomalous right coronary artery origin in otherwise unexplained infant death. Arch Pathol Lab Med 1988;112: Taylor AI, Rogan KV, Virmani R. Sudden cardiac death associated with isolated congenital coronary artery anomalies. J Am Coli Cardiol 1992;20: Cheitlin MD, De Castro CM, McAllister HA. Sudden death as a complication of anomalous left coronary origin from the anterior sinus of Valsalva. Circulation 1974;50: Liberthon RR. Case records of the Massachusetts General Hospital. N Engl J Med 1989;320: Fernandez ED, Kadivar H, Hallman GL, Reul GS, Ott DA, Cooley DA. Congenital malformations of the coronary arteries: the Texas Heart Institute experience. Ann Thorac Surg 1992;54: Bett JHN, O'Brien MF, Murray PJ. Surgery for anomalous origin of the right coronary artery. Br Heart J 1985;53: Di Lello F, Mnuk JF, Flemma RI, Mullen De. Successful coronary reimplantation for anomalous origin of the right coronary artery from the left sinus of Valsalva. J Thorac Cardiovasc Surg 1991;102: Nelson-Piercy C, Rickand AF, Yacoub NH. Aberrant origin of the right coronary artery as a potential cause of sudden death: successful anatomical correction. Br Heart J 1990;64: Mustafa I, Gula G, Radley-Smith R, Durrer S, Yacoub M. Anomalous origin of the left coronary artery from the anterior aortic sinus: a potential cause of sudden death. J Thorac Cardiovasc Surg 1981;82: Tector AJ, Schmahl TM, Janson B, Kallies JR, Johnson G. The internal mammary artery graft: its longevity after coronary bypass. JAMA 1981;246: