Importance of a second spasm provocation test: Four cases with an initial negative spasm provocation test

Figure 1 Coronary angiograms during the first and second spasm provocation test in case 1. A: The first spasm provocation test (SPT) showed negative results after intracoronary infusions of acetylcholine (ACh) with 50 µg for the right coronary artery (RCA) and 100 μg for the left coronary artery (LCA); B: The second SPT showed positive RCA results with an infusion of 30 μg ACh, accompanied by the usual chest symptoms and electrocardiogram changes, despite negative LCA results after an intracoronary infusion of nitroglycerin (NTG). Arrows indicate coronary spasm.