请将下文翻译为英文：冠状动脉异常起源于主动脉Anomalous aortic origin of a coronary artery AAOCA是较罕见的先天性冠脉异常其发病率约为012-1711。AAOCA也是青少年心源性猝死常见的原因之一2尤其是运动员 3。它常合并其他先天性心脏病也可孤立存在。AAOCA早期临床症状不明显多达38-664的患者猝死前从未出现过任何相关症状如患者存在冠状动脉缺

Anomalous aortic origin of a coronary artery (AAOCA) is a rare congenital coronary artery anomaly, with an incidence rate of approximately 0.12%-1.71%1. AAOCA is also one of the common causes of sudden cardiac death in adolescents2, especially in athletes3. It is often associated with other congenital heart diseases but can also occur in isolation. Early clinical symptoms of AAOCA are not obvious, with up to 38%-66%4 of patients experiencing no relevant symptoms before sudden death. If coronary ischemia is present, corresponding clinical symptoms may occur, including syncope, chest pain, palpitations, chest tightness, and fatigue after exertion or vigorous exercise. AAOCA can be classified into five types based on the course of the anomalous coronary artery: between the great vessels, below the pulmonary artery (within the cone or in the interventricular septum), anterior to the pulmonary artery, behind the aorta, and behind the heart4. Among them, between the great vessels and behind the aorta are the most common, accounting for nearly 80%1. Based on the different origins of the anomalous coronary artery, it can be divided into anomalous left coronary artery arising from the right coronary sinus (ALCA-R) and anomalous right coronary artery arising from the left coronary sinus (ARCA-L), with a ratio of approximately 1:65. However, the incidence rate of ALCA-R in the population is only 0.01%~0.04%6, and single coronary artery originating from "no sinus" is extremely rare.

Currently, the gold standard for diagnosing coronary artery anomalies is coronary computed tomography angiography (CCTA) or coronary angiography, but these methods are invasive and costly. Transthoracic echocardiography (TTE) is the preferred non-invasive screening tool for coronary artery anomalies, and it carefully scans the coronary arteries when combined with other congenital heart diseases or coronary dilation. There have been few reports on the use of TTE for diagnosing AAOCA, especially in cases of isolated AAOCA with normal cardiac structures. In this study, we aim to improve the understanding of isolated AAOCA and the accuracy of TTE diagnosis by summarizing the clinical and ultrasound characteristics of AAOCA patients diagnosed with TTE at our hospital over the past three years