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Most medical literature regarding the anomalous origin of a coronary artery from the opposite sinus of Valsalva pertains to sudden death in the young. The surgical treatment of anomalous origin of the left main coronary artery from the right sinus of Valsalva is not particularly well codified, and when an anomalous left main coronary artery is associated with an extramural stenosis, treatment becomes more technically challenging. Herein, we describe a unique approach toward treating this combination of conditions.
A 15-year-old adolescent boy was diagnosed with anomalous origin of the left main coronary artery from the right sinus of Valsalva. The condition was accompanied by a slit ostium and an extramural stenosis of the left main coronary artery. Surgery was offered to the patient in view of his young age and the uncertain prospective course of the disease. Coronary unroofing was not indicated, due to the extramural location of the stenosis. With the patient under cardiopulmonary bypass, the stenotic segment of the left main coronary artery was transected outside the aorta, repaired by vein patch augmentation, and reimplanted directly into the left coronary sinus. The patient recovered uneventfully. A postoperative computed tomographic angiogram showed good patency of the reconstructed artery. We expect excellent longevity of the directly reimplanted coronary artery.
Most of the medical literature regarding the anomalous origin of a coronary artery from the opposite sinus of Valsalva pertains to sudden death in young individuals.1,2 Anomalous origin of the left main coronary artery (LMCA) from the right sinus of Valsalva is observed less frequently than is anomalous origin of the right coronary artery (RCA) from the left sinus,1,3 and the surgical treatment for the former condition is less clearly codified than that for the latter.4 When an anomalous LMCA is associated with an extramural stenosis, treatment becomes more technically challenging. Here, we describe a unique approach for treating these conditions, upon their diagnosis in a 15-year-old patient.
In January 2007, a 15-year-old adolescent boy was admitted to our hospital's emergency department due to the sudden onset of sharp chest pain and syncope that had occurred 30 minutes before admission. The signs and symptoms included stiff arms, froth in the mouth, and defecation several minutes after he had begun to play soccer at school. He had experienced exertion-related syncope 7 times before (over the past 5 years, from December 2001 through January 2006). Previously, the syncope had improved rapidly, without the need for resuscitation. In January 2006, when the 7th episode occurred, he visited our pediatric hospital for the 1st time. A tilt-table test produced negative results, and there was no suspicion of coronary insufficiency. The current presentation was our patient's 8th episode of syncope, this time accompanied by chest pain. The pain strongly suggested typical angina, on the basis of its location and characteristics. After the symptoms were relieved, electrocardiography revealed a suspicious ST-segment elevation. Emergency coronary angiography showed an intact RCA; however, the LMCA originated from the right sinus of Valsalva and exhibited a substantial stenosis of the proximal LMCA (Fig. 1A). During the coronary angiographic study, the catheter tip was placed in the left coronary ostium; however, it could not be advanced from the ostium into the LMCA due to the acute angularity of that artery's origin. Accordingly, we did not consider coronary artery stenting to be a viable treatment. In order to inspect the patient's coronary anatomy in more detail, we performed 64-slice multidetector computed tomographic angiography (CTA). The imaging clearly revealed that the LMCA originated from the right sinus and coursed between the ascending aorta and the pulmonary trunk before reaching its normal bifurcation. In addition, we observed a long stenosis that extended along the proximal portion of the LMCA (Fig. 2). Given the uncertain prospective course of this condition and the young age of the patient, we proposed surgical treatment.
The operation was performed via a median sternotomy. With the patient under cardiopulmonary bypass, we dissected the anterior wall of the aortic root from the posterior wall of the main pulmonary artery, and retracted the pulmonary artery anteriorly in order to expose the proximal portion of the LMCA. The LMCA originated from the right sinus, coursed intramurally anterior to the aortic root, and bulged out from the aortic wall in a transverse line. The stenotic extramural portion of the LMCA was dissected from its takeoff point to its bifurcation, the ascending aorta was clamped, and cardioplegic solution was infused. The aorta was incised transversely 1 cm above the course of the LMCA. We confirmed the intramural course of the LMCA and identified a slit in its ostium, just to the left of the RCA in the right sinus (Fig. 1B). The extramural segment of the LMCA was dissected in the groove between the aorta and the pulmonary artery. The LMCA was divided by transecting the artery just outside the aorta, and the distal stump of the intramural segment and the slit ostium in the right sinus were oversewn with use of continuous 6-0 polypropylene sutures. The artery was mobilized beyond its distal bifurcation, and the proximal stenotic lumen was opened via a longitudinal incision in the inferior wall to a point 2 mm above the distal bifurcation. The LMCA was enlarged by the insertion of a rectangular saphenous vein patch that was secured with a continuous 7-0 polypropylene suture. A circular part of the aortic wall, 4.5 mm in diameter, was removed from the left coronary sinus, and the enlarged artery was reimplanted directly into the opening in the sinus with a continuous 6-0 polypropylene suture. Because we had extensively mobilized the LMCA, the anastomosis was not technically difficult. The reimplanted LMCA was sufficiently long and introduced no tension.
The patient's postoperative course was uneventful. Follow-up CTA was performed 18 months postoperatively, and the results confirmed the lateral translocation and good patency of the LMCA, with no stenosis at the anastomotic site (Fig. 3). The patient remained asymptomatic at his 29-month follow-up examination.
When patients with coronary anomalies display symptoms that include chest pain, syncope, or dyspnea, one should be alert for conditions that can lead to sudden death.1 Computed tomographic angiography is an appropriate method for defining the origin and course of coronary artery anomalies. In particular, the current computed tomographic scanners equipped with 64 detectors are able to define pathologic coronary artery anatomy almost as clearly as can selective coronary angiography.5
When indicated on the basis of symptoms, 2 interventional surgical approaches can be used to treat anomalous origin of the LMCA from the right sinus: one is the local direct repair of the anomalous origination in the aortic root, and the other is coronary artery bypass grafting. Although bypass surgery is technically feasible with use of routine techniques, it has some disadvantages.1,4 In a young patient who has a potentially long life expectancy, vein grafts are usually a poor choice, due to the limited longevity of the vein. Arterial conduits are not suitable for this indication, because they tend to atrophy or fail to develop because of competitive flow when they are used to bypass a coronary lesion that is not severely stenotic. Local repair of the anomalous proximal coronary segment is a reliable solution when it is certain that intramural stenosis is the crucial pathophysiologic mechanism. Unroofing the entire intussuscepted segment or creating a new ostium at the distal end of that segment may be the most propitious option.6 In cases where the left and right coronary arteries' orifices are separated but are located in the same sinus, coronary reimplantation into the correct aortic sinus is the preferred approach.7 In our patient, a long stenosis was observed in intramural and extramural segments; accordingly, none of the above techniques was appropriate for repairing the anomalous origin of the LMCA. For example, although a new ostium at the exact level could have been created to connect to the extramural segment, the stenosis of the extramural segment would not have been resolved.
Our approach was to separate the stenotic extramural segment from the aortic wall and then enlarge it with a rectangular saphenous vein patch before reimplantation. The repositioning of the enlarged LMCA without tension or kinking was facilitated by extensive dissection and mobilization of the LMCA. This operation involved a cut at the epiaortic site of the LMCA, an augmentation of the stenotic segment with use of a rectangular patch, and anastomosis to the left coronary sinus, which may be the most physiologically and anatomically correct solution. In particular, because the vein patch is more flexible than the LMCA, the LMCA may more easily adjust to angulations between the anastomotic plane and the aortic wall, without kinking. When the extramural segment of the LMCA is long enough to reach the correct sinus, direct reimplantation of the LMCA can be a useful surgical treatment for anomalous origin of the LMCA from the right sinus, even though the artery may be stenotic. In addition, excellent longevity of the directly reimplanted artery can be expected.
Address for reprints: Jong Bum Choi, MD, Department of Thoracic & Cardiovascular Surgery, Chonbuk National University Medical School, 634-18 Geumam-dong, Jeonju, Chonbuk 561-712, ROK
This paper was supported by research funds from Chonbuk National University in 2008.