Effect of adenosine on myocardial perfusion in acute anterior myocardial infarction patients treated with emergency percutaneous coronary intervention evaluated by myocardial contrast echocardiography

Objective To study the effect of periprocedural intravenous administration of adenosine on myocardial perfusion by myocardial contrast echocardiography(MCE)in acute anterior myocardial infarction patients treated with emergency percutaneous coronary intervention(PCI).Methods Forty patients,admitted between November 2008 to January 2010,with acute anterior myocardial infarction undergoing emergency PCI were randomly assigned to the Adenosine Group(n = 23)or the Control Group(n =17)within 12h of infarct onset.Adenosine(50 μg·min-1·kg-1)was started to infuse 10 min before coronary intervention.TIMI blood flow was evaluated immediately after PCI and MCE was done 7 days after the procedure for evaluation of myocardial perfusion.Routine UCG was done to examine the LVEF and all the patients were followed up for at least 1 month to observe any incidence of cardiac events.Results There was no significant difference in the incidence of TIMI 0-2 between two groups(17.6% vs 11%,χ2 = 0.00,P 0.05).Perfusion of 73 segments and 52 segments were analyzed separately in the Adenosine Group and the Control Group.The primary end point was myocardial perfusion as determined by MCE imaging.Myocardial perfusion in the Adenosine Group was better than that in the Control Group.A significant difference in the myocardial blood velocity(β)was observed in the Adenosine Group when compared with the Control Group(0.12 ± 0.04 vs 0.09 ± 0.03,t = 5.00,P 0.05),and the myocardial blood flow(A·β)was also increased in Adenosine Group(0.75 ± 0.40 vs 0.52 ± 0.26,t = 3.61,P 0.05).More segments in Control Group restored high level reperfusion(42.5% vs 17.3%,χ2 = 47.204,P 0.05).The left ventricular ejection fraction(LVEF)was higher in Adenosine Group compared with the Control Group [(50.87 ± 5.57)% vs(46.12 ± 6.29)%,t = 2.52,P 0.05].Conclusions The periprocedural intravenous administration of adenosine in acute anterior myocardial patients treated with PCI could improve myocardial perfusion and restore more segmental reperfusion.The left ventricular systolic function could be improved by the administration of adenosine.MCE could provide a reliable,portable assessment of myocardial perfusion.