Pyridostigmine-induced coronary artery spasm in early-onset myasthenia gravis: a case presentation and review of the literature.

We present a case of pyridostigmine-induced coronary artery spasm in a woman with early-onset myasthenia gravis (MG) who suffered from acute chest discomfort a few days after pyridostigmine dose up-titration. Twelve-lead ECG demonstrated ST-segment elevation in inferior limb leads together with sinus arrest. Sublingual nitrate was immediately given, which rapidly relieved her symptoms concomitantly with the resolution of abnormal ECG findings. Coronary angiography showed normal coronary arteries reflecting the transient nature of the disease. A small dose of pyridostigmine was rechallenged under close monitoring in the coronary care unit and reproduced her chest discomfort. After the substitution of pyridostigmine with immunosuppressive agents and prescription of long-acting nitrate, she had no recurrence of chest discomfort, as well as well-controlled MG symptoms.