Vieussens' Arterial Ring and Exercise-Induced Polymorphic VT: Approach to Diagnosis and Management.

Background: Vieussens' arterial ring (VAR) is an embryologic remnant of the conotruncal circle and a rare coronary anomaly.

Case Summary: A 36-year-old man presented for a stress test for evaluation of exercise-induced palpitations. During the test, he developed sustained polymorphic ventricular tachycardia (VT) that self-terminated. Coronary angiography revealed nonobstructive coronary artery disease and type 3 VAR, with the right coronary artery supplying the entire left system. Extensive testing for other etiologies was negative. A repeat stress test after initiation of beta-blocker showed normal myocardial perfusion and no VT. After multidisciplinary patient-centered discussion, surgical revascularization was not pursued. An implantable cardioverter-defibrillator was inserted for secondary prevention, with no recurrence of VT on follow-up.

Discussion: We report an exceedingly rare case of type 3 VAR and polymorphic VT in a young, otherwise healthy man, with successful conservative management. Multimodality testing and a patient-centered approach are essential for accurate diagnosis and effective management.

Take-home Message: Conservative management for VAR is reasonable in the absence of demonstrable myocardial ischemia and/or poor surgical candidacy.