Time-to-treatment significantly affects the extent of ST-segment resolution and myocardial blush in patients with acute myocardial infarction treated by primary angioplasty.

Abstract

The prognostic role of time-to-treatment in primary angioplasty is still a matter of debate. The aim of our study was to evaluate the relationship between time-to-treatment and myocardial perfusion in patients with ST-segment-elevation myocardial infarction (STEMI) treated by primary angioplasty. Our study population consisted of 1072 patients with STEMI treated by primary angioplasty from 1997 to 2001. Myocardial perfusion was evaluated by using ST-segment resolution and myocardial blush grade. Time-to-treatment was defined as the time from symptom-onset to the first balloon inflation. Time-to-treatment was significantly associated with the extent of ST-segment resolution, myocardial blush grade, enzymatic infarct size, and 1-year mortality. After adjustment for baseline confounding factors, time-to-treatment was still associated with impaired ST-segment resolution (adjusted OR [95% CI]=1.01 [1.01-1.02], p<0.001) and myocardial blush (adjusted OR [95% CI]=1.01 [1.01-1.02], p<0.0001). This study shows that in patients with STEMI treated by primary angioplasty prolonged ischaemic time is associated with impaired myocardial perfusion, larger infarct size, and higher 1-year mortality. Therefore, all efforts should be made to shorten ischaemic time as much as possible to achieve better myocardial perfusion and myocardial salvage in primary angioplasty for STEMI.