Clinical Research Of Myocardial Perfusion Imaging Using Adenosine Loading ²⁰¹Tl On The Survival Myocardium In Area Of Coronary Chronic Vascular Occlusion

Objective: To evaluate the accuracy and safety of myocardial perfu- sion imaging using adenosine loading 201Tl on the survival myocardium in area of coronary chronic vascular occlusion.Method: 30 patients, who were conformed as victims of coronary chronic vascular occlusion by 16 multi-slice coronary computer tomography angiography(CTA),were injected adenosine through intra-vein with constant speed. 201Tl(3mCi) was not shot until the end of the third minute after the adenosine introduced by means of bolus injection,then the injection of adenosine lasted six minutes.After 10 minutes,loading phase was collected, and the redistributed imaging was gathered after 3 hours.All of the patients were performed coronary angiography (CAG) within 1 week.Result: 23 of 30 patients exist collateral circulation using myocardial perfusion imaging,while 21 patients present collateral circulation by CAG.The sensitivity and specificity of myocardial perfusion imaging are 95.4% and 75%,the accuracy of positive and nagetive prediction is 87.5% and 90%.The cohorts were divided into two groups,positive and negative group,according to the occurrence of collateral circulation detected by CAG. The difference of integral equal to the minus of the integral between loading imaging and delayed imaging of two groups.The mean difference of integral is 1.03±0.84 in collateral circulation group, yet it is 0.31±0.56 in the other group (P=0.033).There is significant deviation.After adenosine injection,the heart rate (HR) increases, furthermore systolic pressure(SP) and diastolic pressure (DP) decrease (P<0.05),but there is no significant deviation in them (P>0.05).In the process of adenosine injection,only one case appeared the depression of ST segment and relieved through extenuation.No adverse reactions were observed in all the other patients .Conclusion: Myocardial perfusion imaging using adenosine loading 201Tl can evaluate the survival myocardium in area of coronary chronic vascular occlusion commendably.It is also safe.The larger the minus of the integral between loading imaging and delayed imaging of every segments, the more the survival myocardium .The former is correlation with whether existing collateral circulation or not.