Abstract
ST-segment alternans indicates nonuniformity of ventricular repolarization in time and space, and consequently correlates with the occurrence of ventricular fibrillation during cardiac ischemia.
1,2 ST alternans has been observed during spontaneous and induced myocardial ischemia in experimental animals
1,3 and in man during exercise,
4 Prinzmetal angina
5,6 and coronary angioplasty.
7–9 Whereas ST-segment shifts (particularly ST-segment elevation) are frequent during angioplasty,
10 ST-segment alternans is infrequent. We present a patient who on sequential balloon inflations during coronary angioplasty demonstrated a sequence of ST-segment shifts recorded by intracoronary electrocardiography, reflecting the unique effects of repeated short episodes of ischemia on the alternans phenomenon.
