Comparison of outcomes of direct stenting versus stenting after balloon predilation in patients with acute myocardial infarction (DIRAMI)

Due to recent advances in stent design, stenting without balloon predilation (direct stenting) has become more extensively used in patients with acute myocardial infarction (AMI). We performed a randomized study with broad inclusion criteria and early randomization after presentation to compare direct stenting with stenting after balloon predilation in patients with AMI. A total of 248 patients was randomized. After exclusion of patients not suitable for stenting, the final study group comprised 217 patients. Direct stenting strategy was feasible in 88% of patients with no meaningful complications. Final Thrombolysis In Myocardial Infarction grade 3 flow (96% vs 94%), final Thrombolysis In Myocardial Infarction myocardial perfusion grade 2 or 3 (68% vs 61%), and average ST-segment resolution after the procedure (49% vs 51%) were similar in the direct stenting and predilation groups, respectively (p = NS). Rate of in-stent restenosis was higher in the direct stenting group (30% vs 16%, p = 0.024), which was due to a worse angiographic result after the procedure. At 5 years, a composite of cardiac death, reinfarction, and target lesion revascularization had occurred in 39% in the direct stenting group and 34% in the predilated group (p = 0.40). In conclusion, although at 5 years clinical outcome did not differ significantly between groups, direct stenting was associated with a higher incidence of in-stent restenosis at 1 year. Direct stenting did not improve epicardial and myocardial reperfusion indexes. Direct stenting strategy should not be recommended in all patients with AMI as an alternative strategy to stenting after predilation.