The Trendy Anomalous Aortic Origin of the Coronaries, Should We Start Revising the Pre-Participation Guidelines?

1-Taxonomy and Nomenclature of Anomalous Origin of the Coronaries

The RCA originates from the aorta’s right side through the right aortic cusp, branches into the right marginal and posterior descending arteries, supplying the right atrium, right ventricle, SA and AV nodes, parts of the left ventricle, and posterior septum. The LCA, from the left side arising through left aortic cusp, branches into the left anterior descending (LAD) and left circumflex (LCx) arteries, which supply the left atrium, anterior and lateral left ventricle, and apex[6].

Understanding the intricate anatomy of the coronary arteries allows a greater comprehension of the pathophysiology that leads to sudden cardiac death in this condition. As detailed in the sections above, coronary artery anomalies are changes in the anatomy of the coronary arteries. Coronary anomalies’ classification is illustrated in Table 1. [7]

The most frequently observed pathway for an anomalous right coronary artery (RCA) originating from the sinus of Valsalva is interarterial, which means it runs between the ascending aorta and the pulmonary trunk. This variation is linked to a risk of sudden death in as much as 30% of affected individuals. It is thought that during physical exertion, the aorta's expansion can constrict the anomalous opening, leading to decreased blood flow in the coronary artery and increasing the risk of ischemic changes in the heart muscle [8].

In over 75% of patients with the left coronary artery (LCA) arising from the right sinus, the LCA may take an interarterial path, whether as a distinct vessel or as a branch of a common coronary artery. The heightened risk of sudden death is attributed to the sharp angle at the ostium, the "stretching" of the intramural segment, and the compression that occurs between the right and left coronary cusps. Sudden death may happen due to temporary compression of the LCA's anomalous route, which can be triggered by the dilation of the aorta and pulmonary artery during vigorous exercise, leading to torsion or compression of the coronary artery between the aorta and the right ventricular outflow tract[9].

2-Anomalous Aortic Origin of the Coronaries, Relatively Silent Anomalous!

Most cases with anomalous aortic origin of the coronaries are asymptomatic and their first encounter is usually a serious symptom ranging from syncope or ischemic chest pain to aborted or non-aborted sudden cardiac death. The European registry has published its report on this topic recently in 2024. Out of 262 patients, a total of one hundred thirty-nine patients (53.1%) exhibited symptoms, with chest pain being the most prevalent complaint (n = 74, 53.2%), followed by syncope (n = 21, 15.1%). Additionally, seven patients (5%) experienced a myocardial infarction, while two patients (1.4%) had aborted sudden cardiac death. The most observed condition was right anomalous aortic origin of the coronary artery (right-AAOCA), found in 150 cases (57.5%), followed by left anomalous aortic origin (left-AAOCA) in 51 cases (19.5%), and circumflex AAOCA in 20 cases (7.7%)[10].

The American heart association has published a similar article. In half of the cases (n=80, 49%), the diagnosis was found incidentally. The remaining patients exhibited various symptoms: exertional symptoms (n=35, 21%), non-exertional symptoms (n=32, 20%), a family history of cardiovascular disease (n=8, 5%), sudden cardiac arrest or shock (n=5, 3%), and issues related to arrhythmia or bradycardia[11].

This concludes that most of cases with AAOCA will remain asymptomatic until they present with an aborted or sudden cardiac death.

3-Do We Need to Revise the Current Pre-Participation Screening Guidelines?

The current guidelines of the American Heart Association outlines 14 key prescreening elements – such as a history of elevated systemic blood pressure, knowledge of certain cardiac conditions in family members, and the presence of a heart murmur – that are designed to identify, or at least raise the suspicion of, cardiovascular diseases that place certain athletes at risk. Patients would receive ECGs, echocardiograms, and other follow-up tests if the screening indicates the presence of a problem[12,13].

The AHA refuses to implement mass ECG or echocardiography-based screening programs. Implementing a widespread ECG screening program could place a significant burden on the healthcare system, as there may not be enough qualified medical professionals available to accurately interpret the results. It is crucial to highlight that both false positive and false negative results are a concern [14]. A recent systematic review indicated that the false positive rates for physician-interpretated ECGs in athletes typically range from 1.3% to 2.8% but can reach as high as 26.8% among Arab and Black athletes. In contrast, computer-interpretated ECGs show false positive rates between 2.3% and 5%. Additionally, 12-lead ECGs have been associated with a 10% false-negative rate for hypertrophic cardiomyopathy, the leading cause of sudden cardiac death in athletes. Mandating ECGs for all athletes may also be a challenge for children from low-income backgrounds unless there is adequate financial assistance. It is vital to acknowledge this issue, especially since studies indicate that certain racial groups might have a higher risk of sudden death. Therefore, prescreening programs that rely on costly tests must find solutions to address these significant access inequalities.

In contrast Italy has adopted since 1982 a strict pre-participation program. In the Veneto region of Italy, the occurrence of sudden death (SD) among competitive athletes saw a significant drop of 89% over the 21 years following the introduction of annual screening legislation. The pre-participation guidelines for amateur competitive athletes are outlined by Italian legislation and regional rules. These protocols are conducted by a physician who has obtained a specialty in sports medicine after four years of full-time training, which includes comprehensive training in ECG analysis. The initial assessment comprises a medical history review, a physical exam, a visual acuity evaluation using a Snellen chart, a resting 12-lead ECG, stress testing for ECG, spirometry, and a urine dipstick test [15].

Between the restrictive American guidelines and the rigorous Italian strategy, we still wander and wonder if it is enough.

As mentioned earlier, the second leading cause among young athletes is the anomalous aortic origin of the coronary arteries. This diagnosis remains largely incidental, and it is manifested usually during exercise, which means that a resting ECG might miss the diagnosis[10].

This opens a new debate on the need of adding a stress-ECG or echocardiography to pre-participation screening. This strategy faces debates of cost effectiveness, and also the false positive disqualifications, with the multiple unknowns related to this trendy diagnosis.