RESUMO
Primary percutaneous coronary intervention [PCI] has resulted in marked reduction in the incidence of reinfarction death and stroke in the setting of acute myocardial infarction. However, its beneficial effects are limited by reperfusion injury. Adenosine limits reperfusion injury in animal models. The aim of this study was to evaluate the feasibility safety and value of intracoronary adenosine as an adjunct to primary PCI in acute myocardial infarction. The study included 60 patients with acute ST-elevation myocardial infarction within 6 hours of the onset of chest pain referred for primary PCI. Patients were divided into two groups, the adenosine group, included 20 patients who received intracoronary adenosine as an adjunct to primary PCI; and the control group, included 40 patients, who received saline instead. All patients had 12-lead ECG before and after intervention cardiac enzynes estimation and detailed assessment of angiographic data during PCI emphasizing on post-intervention TIMI flow and TIMI myocardial perfusion grading [TMP]. Conventional and pulsed tissue Doppler examinations were done within 24 hours after PCI and one week later to evaluate wall motion and myocardial velocities within the reperfused segments. Both groups were matched in teens of age sex risk factors, infarct location and distribution of coronary artery disease. Though the mean time from onset of chest pain to PCI was significantly shorter in the control group, the adenosine group demonstrated significantly lower enzymatic peaks [1880.3 +/- 1020.4 versus 2806 +/- 1379.8; P < 0.01], significantly higher incidence of TIMI III flow [95% versus 65%; P < 0.03]. significantly higher incidence of TMP III grace [85% versus 40%; P < 0.007], significantly lower TIMI frame count [11.5 +/- 3.1 versus 23.1 +/- 9.8 frames: P < 0.0001] and markedly lower incidence of no-reflow compared to the control group [10% versus 45% P < 0.006] at day 7, only adenosine group demonstrated significant improvement in ejection fraction, systolic wall motion score indices with striking improvement in the annular and segmental S wave velocities recorded by tissue Doppler. Adenosine administration in the setting of primary PCI for ecute myocardial infarction is safe, significantly limits reperfusion injury and improves myocardial perfusion thus optimizing the results of PCI