Mid-Right Coronary Artery Spasm Diagnosed by an Ergometrine Provocation Test Through a Saphenous Vein Graft.

Although coronary artery spasm is a cause of acute coronary syndrome (ACS), demonstration of its possible cause in patients with a history of coronary artery bypass grafting remains challenging. We report a case of ACS that successfully provoked coronary artery spasm by pharmacological testing through a saphenous vein graft. (Level of Difficulty: Beginner.).