ABSTRACT
Coronary vasospasm of the left main coronary artery (LMCA) is a rare condition with potentially devastating consequences. We present 2 patients with LMCA vasospasm-related angina, the first being a 46-year-old woman and the second a 51-year-old woman. Both of them developed ST-segment ischemic changes on treadmill exercise tests. Coronary angiography showed spontaneous LMCA vasospasm in one patient and methylergonovine-induced LMCA vasospasm in the other patient. Follow-up treadmill exercise tests revealed no exercise-induced ischemia after calcium antagonist monotherapy. These cases demonstrate the importance of identifying LMCA vasospasm, as the treatment of choice varies in patients with angina pectoris. Reversible myocardial ischemia caused by LMCA vasospastic angina can be controlled by calcium antagonist monotherapy and detected by repeat non-invasive stress testing.