From the Guidelines
The described coronary anomaly is an anomalous right coronary artery (RCA) originating from the left side of the right coronary cusp with a proximal intramural course, which is a potentially significant coronary anomaly that requires careful evaluation and management, and according to the most recent guidelines 1, surgical intervention may be necessary, especially if the patient is symptomatic or has evidence of myocardial ischemia on functional testing. The preferred surgical approach is typically unroofing of the intramural segment, which creates a new ostium at the end of the intramural course. Some key points to consider in the management of this anomaly include:
- Comprehensive cardiac imaging, typically with coronary CT angiography or cardiac MRI, to fully characterize the anatomy and assess for compression of the vessel 1.
- Assessment for inducible myocardial ischemia, which can be done using various stress testing modalities, such as stress echocardiography or nuclear perfusion imaging 1.
- Activity restrictions, particularly avoiding intense competitive sports, may be appropriate for asymptomatic patients with no evidence of ischemia 1.
- The risk of sudden cardiac death (SCD) associated with this anomaly, especially during physical exertion, and the importance of careful evaluation and management to mitigate this risk 1. It's also important to note that the current guidelines recommend surgical intervention for patients with anomalous aortic origin of the coronary artery who have symptoms attributable to the coronary anomaly or have a positive stress test 1. In addition, the guidelines suggest that asymptomatic patients with high-risk anatomical features, such as an intramural course, should also be considered for surgical intervention 1. Overall, the management of this coronary anomaly requires a careful and individualized approach, taking into account the patient's symptoms, anatomy, and risk factors for SCD.
From the Research
Anomalous Origin of the Right Coronary Artery
- The right coronary artery (RCA) coming off leftward from the right coronary cusp with a proximal intramural course is a rare congenital anomaly associated with increased risk of myocardial ischemia and sudden death 2, 3.
- Studies have shown that an initial intramural course of the coronary artery within the aortic media can cause myocardial ischemia in cases of coronary anomalies 2.
- The prognosis of patients with this anomaly is unequal, and additional factors that diminish blood flow in the intramural segment may be required to cause significant myocardial ischemia 2.
Clinical Outcomes and Management
- Clinical outcomes in adult patients with an anomalous right coronary artery from the left sinus of Valsalva have been assessed, and the results suggest that most patients who survive this anomaly into adulthood may be managed conservatively without intervention 4.
- A study found that there was no difference in mortality between patients with R-ACAOS-IM and those with anomalous left circumflex coronary arteries with retroaortic course (LCx-RA) 4.
- Surgical correction and reimplantation of the right coronary artery may be a safe and effective technique for managing this anomaly 3.
- Stent-percutaneous coronary intervention (PCI) with intravascular ultrasonography (IVUS) monitoring has also been shown to be effective in managing patients with this anomaly 5.
Pathophysiology and Risk Factors
- The intramural course of the RCA within the aortic media may be an accelerating factor of decreased blood flow in cases with an origin of the RCA arising from the left coronary sinus 2.
- Inciting factors that increase blood pressure may also play a role in causing symptomatic myocardial ischemia by initiating mechanical compression from the aorta to the intramural segment of the RCA 2.
- Atherosclerotic narrowing of the RCA and acute ischemic necrosis in the posterior basilar ventricular septum may also contribute to the risk of sudden cardiac death in patients with this anomaly 2.