Transient ST-Segment Elevation During Cryoablation of the Right Inferior Pulmonary Vein in Atrial Fibrillation

BACKGROUND: Cryoballoon ablation is a widely used technique for pulmonary vein isolation in atrial fibrillation. Coronary artery spasm (CAS) is a rare but serious complication during this procedure. CASE SUMMARY: A 73-year-old man with persistent atrial fibrillation underwent cryoablation. During ablation of the right inferior pulmonary vein (RIPV), abrupt ST-segment elevation (2-3 mm in the inferior leads) occurred alongside hypotension and tachycardia. Immediate cessation of cryoenergy resulted in spontaneous resolution of electrocardiographic changes and hemodynamic recovery, consistent with CAS. DISCUSSION: This case suggests that RIPV cryoablation may trigger CAS via direct cryothermal stimulation or autonomic neural reflexes. Pre-existing endothelial dysfunction from hypertension, diabetes, and smoking history likely increased susceptibility. Prophylactic nitroglycerin may not consistently prevent spasms in peripheral venous access. TAKE-HOME MESSAGES: Vigilant real-time electrocardiographic monitoring during RIPV ablation is crucial. Prompt recognition and termination of energy delivery are key to managing this life-threatening complication.