VOJNOSANITETSKI PREGLED ORIGIN OF THE LEFT CORONARY ARTERY FROM THE OPPOSITE SINUS OF VALSALVA AND LEFT MAIN CORONARY ARTERY OCCLUSION

Introduction. Congenital coronary anomalies are detected in around 5% of all performed coronarographies. Coronary artery anomalies considered as those of great risk are the ones arising from the opposite sinus of Valsalva. These anomalies are detected in around 1% of cases. This case report shows a unique case of a patient with anterior wall STEMI caused by left main coronary artery (LMCA) occlusion which arises from the right coronary cusp and has interarterial course, which was successfully treated with primary PCI. Case Report. A 46-year-old male patient was admitted to the hospital due to STEMI of the anterior region. At the admission the patient was hypertensive (150/100 mmHg) in sinus rhythm (heart rate around 70/min), Killip I. After the initial examination and admitting dual antiplatelet therapy, the patient was transferred for urgent coronarography. Coronarography was performed by using the trans-radial approach. The right coronary artery had no significant stenosis and it was easily cannulated, whereas the left coronary artery could not be cannulated at the usual position. The operator attempted to cannulate the left coronary artery with multiple catheters of various curves, unsuccessfully. The conclusion was that there was a coronary artery anomaly, and the cannulation of the anomalous aortic origin of the left coronary artery (AAOLCA) which arises from the opposite right coronary cusp, was successfully performed with a Multipurpose catheter. Moreover, the left coronary artery was occluded in the distal segment. Two drug-eluting stents were implanted and followed by the development of no-reflow phenomenon and cardiogenic shock. After the stabilization, CT coronarography was performed and AAOLCA with an interarterial course was registered. During the follow-up period SPECT was performed and in the staged procedure, the stent was implanted on the proximal Cx, by using the TAP technique. rare. to treat them adequately with primary percutaneous coronary intervention.


Introduction
Congenital coronary artery anomalies (CAA) are detected in around 5% of all performed coronarographies [1]. In the literature, there are 66 different anomalies described, while the ones considered of great risk are anomalous coronary arteries from the opposite sinus of Valsalva (ACAOS). These anomalies are detected in around 1 % of cases. Anomalous aortic origin of the right coronary artery (AAORCA) arising from the left coronary cusp is detected more often, whereas the anomalous aortic origin of the left coronary artery (AAOLCA) arising from the right coronary cusp is detected in 0.15% of the cases [1][2].
With both CAA, there are several different courses, such as pre-pulmonic, retro-aortic, subpulmonic (septal), or interarterial course where the coronary artery is placed between the aorta and the pulmonary trunk. Interarterial course is the only course that can cause sudden cardiac death and, therefore, is considered malignant [3]. STEMI is rarely detected in patients with coronary artery anomalies and is demanding to treat. The very identification and cannulation of the culprit artery with anomalous origin can be quite challenging.
Herein we presented a unique case of a patient with anterolateral wall STEMI, caused by an occlusion of the left coronary artery arising from the right coronary cusp with interarterial course which was successfully treated with the primary percutaneous coronary intervention (PCI).

Case Report
A 46-year-old patient was admitted to the hospital due to anterior wall STEMI ( Figure 1).
Chest pain started 2 hours prior to admission to the hospital. The patient had no prior medical history and the only risk factor for coronary artery disease was smoking. At the admission, the patient was hypertensive (150/100 mmHg) in sinus rhythm (HR 70/min), Killip I. After the initial examination, dual antiplatelet therapy was introduced, and the patient was transferred to the Cath lab for urgent coronarography. On the seventh day of hospitalization, the patient was stabilized and was transferred to the ward. CT coronarography was performed for detailed analyses of the CAA. CT registered anomalous slit-like origin of the left coronary artery from the right coronary cusp (AAOLCA), with the interarterial course (placed between the aorta and pulmonary trunk).
Furthermore, the length of the LMCA was 50mm. Interestingly, the artery at the point of 7.2mm from the orifice at the aorta enters the heart muscle and it passes through up to trifurcation, in all its length. The stents were patent and at the Cx ostia significant lesion was registered. (Figure 3). On the fourteenth day of the hospitalization, the patient was discharged in a good general condition. During the six-month follow-up period, the patient had symptoms of stabile Angina. SPECT was performed, and it showed significant ischemia in the irrigational area of Cx.
Ten months after the STEMI, recoronorography was performed and this time left Amplatz 1 guiding catheter was used, and successful cannulation of LCA and RCA were achieved.
Coronography registered significant stenosis of the ostial Cx, and that the previously implanted stents were patent. As a result, DES 2.5 x 15 mm (Xience Pro, Abbott, USA) was implanted on the ostium of Cx with the TAP technique ( Figure 4).

Discussion
The case report presented a case of a STEMI patient with anomalous origin of the left coronary artery from the right coronary cusp with interarterial course. Besides, the patient had LMCA occlusion in the distal segment. Best to our knowledge, this is a unique case in the literature.
The usage of noninvasive technologies, such as CT and MRI enable detecting and registering coronary anomalies more frequently [3][4]. The detection of CAA deserves special attention. Even though most of these anomalies is benign, coronary arteries arising from the opposite sinus of Valsalva with interarterial course present a risk of sudden cardiac death. It can be caused by many various factors, such as, slit-like orifice or tangential passage of origin, or, it might result from extreme physical activity which can lead to the compression of the anomalous coronary artery with interarterial course. Extreme physical activity can result in increased blood flow through the aorta and pulmonary artery leading to compression which causes ischemia. It is crucial to emphasize that these anomalies present a great risk for the younger population which is exposed to extreme 8 physical activity. This mostly refers to sportsmen, athletes, and military recruits.
Sometimes, the first manifestation can be sudden cardiac death (SCD), however, very often there are symptoms present during the physical activity, such as angina-like symptoms, arrhythmia, presyncope and syncope [5][6].
The literature provides us with a different frequency of atherosclerotic disease in anomalous coronary arteries when compared to normal. Recent studies indicate a slightly higher incidence of coronary artery disease (CAD) in anomalous coronary arteries than what is shown in earlier researches which indicates an equal incidence of CAD [7].
However, STEMI patients with coronary anomalies are quite rare. According to the research conducted by Marchesini et al, only 5 out of 1015 STEMI patients (0.4%) had an anomaly of the coronary artery at the same time [8].
Performing primary PCI in STEMI patients and CAA is challenging for every operator, mostly because of the cannulation problems of the anomalous culprit artery. However, a problem might arise during the procedure, in terms of balloon and stent deliverability in the culprit lesion area. In this case report, the cannulation of the LCA presented a problem, considering that it could not be detected in the left coronary cusp. After exchanging multiple catheters, the operator decided to use a Multipurpose catheter and search for coronary artery in the right coronary and posterior cusp. Luckily, in this case, only the cannulation was challenging, considering the anomalous origin. In both procedures, there was no problem with the device deliverability.
The occlusion of the left main coronary artery is a disastrous event and most of the patients has a fatal outcome, on the way to the hospital. De Luca et al, registered incidence of 0.8% in patients with a myocardial infarction and the LMCA occlusion. Their study registers high intrahospital mortality, which was 58% in all patients, and 80 % in patients who developed cardiogenic shock or had no re-flow, at the end of the procedure. [9]. Certain factors had shown that they contribute to the higher survival rate of these patients, such as dominant RCA, the existence of hetero-collateral circulation, and fast revascularization [10][11][12]. In our case, RCA was dominant, and hetero-collateral showed the very periphery of LAD. However, the existence of hetero-collateral circulation did not imply the anomalous origin of LCA. The operator's experience to assume the presence of coronary anomaly and the adequate selection of catheter allowed successful revascularization of LMCA and proximal LAD.

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Despite the loss of time, of around 15 minutes until the cannulation of anomalous LCA, guidewire passage and establishing anterograde flow through the infraction artery, cardiogenic shock developed, as well as, no-reflow at the end of the procedure. No-reflow developed as a consequence of a high thrombus burden and aggressive post-dilatation during POT, which led to distal embolization with thrombus masses and debris from the lesion, causing microvascular obstruction. Treatment of no-reflow was challenging, because nitroglycerin, adenosine or intracoronary adrenalin could not be given due to hemodynamic and rhythmic instability. Decision to administer GP IIb/IIIa (Tirofiban) with implantation of mechanical circulatory support with IABP and aggressive treatment of cardiogenic shock with the support of invasive mechanical ventilation led to a fast stabilization. It is important to emphasize that the VA-ECMO implantation was considered. However, due to the no-reflow and admitting GP IIb/IIIa inhibitor there was a high risk of bleeding, it was decided to wait and monitor the patient's status. As the satisfactory hemodynamical stabilization was achieved promptly during the treatment at the CCU, the implantation was no longer needed. Since 3D reconstruction is not possible, angiography has a limited sensitivity when it comes to adequate diagnostics of anomalies of coronary arteries. Therefore, to diagnose the type of anomalies, its course and its placement in relation to great vessels, it is necessary to use MSCT or MRI. Applying these methods prior to coronarography can facilitate the cannulation of the anomalous coronary artery, and this option is manageable in elective and stable patients [13].
Surgical approach to AAOLCA and AAORCA anomalies is considered in the patients younger than 35, and who were exposed to high physical efforts and had experienced some of the symptoms which led to the diagnosis of this type of anomaly. When it comes to older patients, the type of treatment should be carefully considered, especially the need for surgical intervention. Especially, if these patients are asymptomatic. Tests for determining ischemia are advised in these patients [14]. Surgery treatment was not taken into the consideration for the patient presented in this case report since the patient did not have any symptoms before the coronary incident and was not exposed to great physical efforts.
SPECT showed ischemia only in the Cx area, which was sub-occluded at the origin and it was revascularized by stent implantation.

10
STEMI patients with coronary artery anomalies are rare and represent a challenge for revascularization, thus, knowing the anatomical varieties is essential to treat these patients with percutaneous coronary intervention.  The left arrow points to the slit-like orifice of AAOLCA, the right arrow points to significant stenosis of ostial Cx.