Quality of myocardial reperfusion according to ischemic time and infarcted territory.

Background: The relationship of the ischemic time to primary angioplasty and the quality of myocardial reperfusion according to infarcted territory among patients with ST-segment elevation myocardial infarction (STEMI) is unclear.
Methods: This study consisted of 140 patients with STEMI within 12 h from the symptom onset and undergoing a primary angioplasty from the Protection of Distal Embolization in High-Risk Patients with Acute ST-Segment Elevation Myocardial Infarction Trial. ST-segment resolution (STR) at 60 min was analyzed by an independent corelab using continuous ST monitoring. Patients were divided according to anterior (n=74) and nonanterior (n=64) locations and according to ischemic time in quartiles (<90, 90-148, 148-241, and 241-635 min).
Results: Although there was no significant decrement in the extent of STR with the ischemic time in the entire population (74, 51, 72, and 51%, respectively, P=not significant), patients with anterior location have a significant reduction in the extent of STR after 90 min compared with those coming after 90 min (70.6 vs. 29.2% of complete STR, P=0.003, respectively).
Conclusion: Patients with anterior STEMI seem to have a stronger impact of ischemic time on the quality of myocardial reperfusion compared with patients with nonanterior location.