New method of intracoronary adenosine injection to prevent microvascular reperfusion injury in patients with acute myocardial infarction undergoing percutaneous coronary intervention.

The aim of our study was to examine the role of a new, simple protocol of intracoronary adenosine administration performed during primary angioplasty on the immediate angiographic results and clinical course. A prospective, single-center, randomized, placebo-controlled trial of 70 consecutive patients (64 ± 14 years, 54 men) with acute myocardial infarction with ST-segment elevation undergoing primary percutaneous coronary intervention (PCI) was conducted. Patients were randomized to 2 groups. Group 1 (n = 35) received intracoronary adenosine (1 to 2 mg) with a hand injection through the guiding catheter 2 times: immediately after crossing the lesion of the infarct-related artery with guidewire and then after the first balloon inflation. Group 2 (n = 35) received placebo. The baseline clinical and angiographic characteristics of the 2 groups were similar. Percutaneous coronary intervention resulted in Thrombolysis In Myocardial Infarction grade 3 flow after PCI in 32 patients (91.4%) in the adenosine group and 27 patients (77.1%) in the placebo group (p = 0.059). Myocardial blush grade 3 was observed at the end of PCI in 23 patients (65.7%) in the adenosine group and 13 (37.1%) in the placebo group (p < 0.05). Resolution of ST-segment elevation (> 50%) was more frequently observed in the adenosine than in the placebo group: 27 (77%) versus 15 (43%), respectively (p < 0.01). In conclusion, intracoronary adenosine administration improved the angiographic and electrocardiographic results in patients with acute myocardial infarction with ST-segment elevation undergoing PCI. Adenosine administration seemed to be associated with a more favorable clinical course.