An unusual image of Vieussens’ arterial ring communicating with the pulmonary artery

Vieussens’ arterial ring (VAR) is a collateral pathway between the conus branches of the right and left coronary arteries that was first described by French anatomist Raymond de Vieussens. VAR’s are observed in 48% of the population; however, pathologic VAR is very rare. A 58 year-old male patient with a history of smoking and positive family history was admitted to our clinic complaining of chest pain. Because of the positive exercise stress test, coronary angiography was performed. His coronary angiography revealed noncritical lesions, but visualized VAR between left anterior descending artery (LAD) (Fig. 1-4) and right coronary artery (RCA) with pulmonary artery fistula (CAF) (Video 1-6). We considered that these collaterals may trigger angina and medical therapy was rearranged. During a follow-up period of 6 months with medical therapy, there was no cardiac event or angina. VAR may provide an important collateral blood flow in cases of proximal LAD, or less commonly, RCA stenosis. VAR will become dilated when there is proximal LAD occlusion, or less frequently, RCA occlusion. Pathological conditions (aneurysm, rupture) involving the ring are extremely infrequent and there are few cases about these complications. The ring may also communicate with the pulmonary trunk. CAF are abnormal connections between coronary arteries, great vessels, or cardiac chambers which incidence is nearly 0.87%. Many studies have investigated CAFs and their possible origins; however, reports of VAR with CAF are very rare. Therefore, our case is important to demonstrate the possible interaction between VAR and CAF. We need further studies to treatment for uncomplicated VAR.