ST-segment elevation in the inferior leads has been previously described following transseptal puncture for balloon mitral valvuloplasty. The mechanism, however, is obscure, and immediate left and right coronary angiography has not suggested that embolism or vascular spasm is the cause. We hypothesized that a neurally-mediated mechanism was responsible and have since treated 3 further patients with inferior ST-segment elevation following transseptal puncture for balloon valvuloplasty with intravenous atropine, with rapid resolution of ST-segment elevation in each case.