Coronary artery fistulae are an uncommon anomaly and, while frequently asymptomatic, may require interventional therapy. Transcatheter approaches for closure of coronary artery fistulae are now commonly used, with various methods of fistula occlusion described, including detachable coils. During a percutaneous procedure to occlude a symptomatic left anterior descending coronary artery to pulmonary artery fistula, the patient experienced chest discomfort with anterior ST segment elevation. We demonstrate an unusual, unique and striking ECG abnormality complicating the delivery of coils designed to occlude the fistula in the absence of coronary artery injury. The mechanisms of the procedural ECG changes are discussed, as are potential alternate diagnoses and associated therapy.