Direct Infarct Artery Stenting Without Predilation and No-reflow in Patients with Acute Myocardial Infarction

Background: In patients with acute myocardial infarction (AMI), the rate of microvascular embolization and no-reflow promoted by coronary stenting with the use of conventional techniques (CS) appears to be greater than the one that occurs with balloon angioplasty. The minor invasiveness of direct stenting (DS) of the infarct artery without predilation could be expected to reduce embolization in the coronary microvasculature and no-reflow in patients with AMI.

Methods: In a cohort of 423 consecutive patients with AMI who underwent infarct-artery stenting, we compared CS and DS in terms of angiographic no-reflow rate and 1-month clinical outcome.

Results: At baseline patients who underwent DS (n = 110) had a better risk profile compared with the use of CS (n = 313). The incidence of angiographic no-reflow was 12% in the CS group and 5.5% in the DS group (P =.040). The 1-month mortality rate was 8% in the CS group and 1% in the DS group (P =.008). The mortality rate was 11% in patients with no-reflow and 5.6% in patients with a normal flow. Multivariate analysis showed that age, preprocedure patent infarct artery, and lesion length were related to the risk of no-reflow. In the subset of patients with a target lesion length </=15 mm, the variables independently related to the risk of no-reflow were age, DS, and final balloon inflation pressure.

Conclusions: DS in patients with AMI may reduce the incidence of angiographic no-reflow, thereby increasing ultimate effective myocardial reperfusion.