Circle of Vieussens: Its Importance in the Presence of Significant Coronary Artery Stenosis in a 26-Year-Old Female With Kawasaki Disease.

In patients with coronary artery disease (CAD), collateral circulation aids in sustaining myocardial perfusion and cardiac function. The circle of Vieussens is a rare collateral pathway between the right coronary artery and the left anterior descending artery (LAD) that plays a significant role specifically in patients with chronic total occlusions (CTOs). This article presents a unique case of the circle of Vieussens in a 26-year-old Asian female with a history of Kawasaki disease and CTO of the proximal LAD. Despite the CTO, the patient remains asymptomatic and maintains normal left ventricular function, attributed to an effective collateral network including a right-to-left arterial ring providing TIMI 3 flow. The case illustrates the crucial role of collateral circulation in managing complex coronary anomalies and underscores the need for comprehensive cardiac evaluations in patients with Kawasaki disease. This finding also highlights the potential of the circle of Vieussens as a lifesaving alternate conduit in severe CAD scenarios.