| Recent studies have suggested that adenosine was a adenine metabolite with various cardiovascular protective effects. Adenosine could relieve reperfusion injury through inhibitting neutrophil adhesiveness and aggregation, protecting vascular endothelial cells function, cleanning oxygen-derived free radicals, and improving the energy metabolism of ischemia cardiomyocyte. Several clinical studies has verified that as a adjunct to reperfusion therapy of acute mayocardial infarction, adenosine could reduce infacted size and decrease incidences of no-reflow phenomenon. But animal studies of adenosine in myocardial reperfusion had contradictory results.Thirty one patients undergoing percutaneous revascularization was enrolled in the clinical study. Fifteen patients was acute myocardial infarction and performed primary PICA, and sixteen patients was old myocardial infarction, and interventional therapy was performed on either saphenous vein grafts or native vessells. After successful PCI therapy, all patients received intracoronary injection of adenosine (15 u g - 60^g) through guide catheter. The angiographic archeives before and after adenosine administration were analyzed by TEMI Myocardial Perfusion Grade (TMPG) and Corrected TEvH Frame Count (CTFC).The results showed that following successful PCI, adenosine infusion through guide catheters could result in transient decrease of heart rate and blood pressure, but reversed in several seconds. No significant hypotension and bradycardia or other adverse clinical events were associated with adenosine administration. Analysis of angiogram demonstrated that the CTFC of culprit coronary artery was significantly decreased after adenosine5treatment(the CTFC of pretreatment > 1 and 10 minute after adenosine treatment were 31.24 ?10.67 > 27.44 ?7.70,27.17 ?8.72 separately, P<0.05 compared with pretreatment angiograme), and TMPG was significantly improved (pretreatment 2.12?.81 vs after treatment 2.48?.74, P=0.02).The no-reflow phenomenon a common complication of percutanous coronary intervention(PCI) therapy of acute myocardial infarction and PCI of saphenous vein grafts, and it is associated with poor functional and clinical outcomes. Angiographic improvement has been achieved with intracoronary administration calcium channel blockers and direct-acting vasodilators such as nitroprusside. However these agents often induce hypotension , aggravating hernodynamic instability.Six patients undergoing percutaneous revascularization procedures complicated with no-reflow that received introcoronary adenosine infusion ( 60 u g - 120^g ) treatment were studied. We found that adenosine administration ( 60 U g - 90fig ) could lead to significant and rapid improvement in TIMI 1 and 2 patients, but the efficacy of adenosine treatment (120 u g) adjunct with verapamil and nitroprusside was rather poor in patients of TIMI 0 grade.We applied dog myocardial infarction reperfusion model and randomized to adenosine group and control group. The dogs of adenosine group(n=10, three dogs died during the procedure) received introcoronary infusion of adenosine(100Mg/kg in 20ml saline) and control group(n=10, four dogs died during the procedure) received equivalence saline after 20 minutes of reperfusion. Serial semi- quantitative single photon emission computerized tomography (SPECT) was performed, and determinated the perfusion defect score of adenosine pretreatment and the perfusion defectscore 3 days after procedure, and calculated the myocardial savage index. Two weeks after the procedure, two dimensional echocardiogram was performed to determinate left ventricular ejection fraction (LVEF), regional wall motion index and left ventricular end diastolic diameter(LVEDD).The results showed that the myocardial perfusion defect score of adenosine pretreatment had no significance difference between adenosine group and control group (17.86?.44 vs 17.51?.32, P=0.84); the myocardial perfusion defect score of 3 day after procedures was significantly reduced in the adenosi...
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