Electrocardiographic recognition of variant angina during permanent pacing

We present a patient with a permanent ventricular pacemaker who was investigated for episodes of chest pain associated with syncope. Ambulatory electrocardiographic monitoring showed essentially paced rhythm. ST segment elevation of the paced beats was observed during spontaneous chest pain, but the significance of this finding was initially unclear in the context of the abnormal repolarization associated intrinsically with paced rhythm. At angiography, coronary spasm was demonstrated after ergonovine, and this was associated with ST segment elevation during paced rhythm and with chest pain. We conclude that ST segment elevation may indicate myocardial ischemia even when observed in the face of abnormal repolarization associated with paced rhythm.