Seismocardiography is a new noninvasive technique for recording cardiac vibrations. Changes in the recorded waves have been correlated with acute and chronic changes in left ventricular function. In this report, we describe a patient who developed ischemia induced by coronary angiography in the cardiac catheterization laboratory. The patient's seismocardiogram showed distinct changes during the ischemic episode that actually preceded the onset of symptoms and resolved after nitroglycerin therapy. The patient's seismocardiographic recordings were significantly different from the recordings from five control individuals. This observation suggests that seismocardiography may be helpful for monitoring left ventricular function during episodes of myocardial ischemia.