Abstract
In patients with recanalized acute myocardial infarction (AMI), the relation between the timing of preinfarction angina (PA) and microvascular reperfusion remains unclear. A total of 186 patients (114 with anterior and 72 with inferior AMI) who had total occlusion and TIMI 3 recanalization ≤ 6 hours from the onset of AMI were divided into 4 groups according to the time interval between the last episode of PA and the onset of AMI: ≤ 2 hours (group A, n = 52); 2 to 48 hours (group B, n = 43), ≥ 48 hours (group C, n = 33), and no PA (group D, n = 58). The angiographic myocardial blush grade, a marker of microvascular reperfusion, was retrospectively assessed immediately after recanalization. There were no differences in baseline characteristics, except for sex among the 4 groups. Myocardial blush grade 3 was more frequent (42% vs 21%, 9%, and 14%) and peak creatine kinase was lower (2659 vs 3455, 4422, and 4622 mU/mL) in group A than in groups B, C, and D (all P < 0.05). Multivariate analysis showed that PA occurring ≤ 2 hours before AMI (OR 3.88, P < 0.05), a smaller summed ST-segment elevation before recanalization (OR 0.84, P <0.01), earlier time to recanalization (OR 0.52, P < 0.05), and inferior AMI (OR 4.87, P < 0.05) were independently associated with adequate microvascular reperfusion. We conclude that PA ≤ 2 hours before the onset of AMI is independently associated with adequate microvascular reperfusion after recanalization in patients with AMI.
