Effect of New Method of Intracoronary Adenosine Injection during Primary Percutaneous Coronary Intervention on Microvascular Reperfusion Injury - Clinical Outcome and 1-Year Follow-Up

<b><i>Objectives:</i></b> The aim of this single-center, randomized placebo-controlled trial in 70 consecutive patients (64 ± 14 years) with acute myocardial infarction was to examine the role of a new protocol of adenosine administration during primary angioplasty on immediate electrocardiographic and angiographic results, clinical outcome and 1-year follow-up. <b><i>Methods:</i></b> Group A (n = 35) twice received intracoronary adenosine through the guiding catheter: immediately after crossing the lesion of the infarct-related artery with guidewire and then after first balloon inflation. Group B (n = 35) received placebo. <b><i>Results:</i></b> Resolution of ST segment elevation was more frequently observed in the adenosine than in the placebo group (p < 0.01). Percutaneous coronary intervention (PCI) resulted in borderline better TIMI 3 flow after the procedure in the adenosine group than in the placebo group. Myocardial blush grade 3 at the end of the procedure was significantly improved in the adenosine compared to the placebo group (p < 0.05). At 1-year the composite end-point of death, recurrent myocardial infarction, heart failure and clinically driven target vessel revascularization was present in 8 patients in the adenosine group and 16 patients in placebo group (p < 0.05). <b><i>Conclusions:</i></b> Intracoronary adenosine improved electrocardiographic and angiographic results in patients undergoing primary PCI and seemed to be associated with more favorable clinical course.