TL-201 MYOCARDIAL TOMOGRAPHY WITH INTRAVENOUS-INFUSION OF ADENOSINE-TRIPHOSPHATE IN DIAGNOSIS OF CORONARY-ARTERY DISEASE

0bjectives. The purpose of this study was to evaluate the feasibility, safety and diagnostic accuracy of thallium-201 myocardial tomography with intravenous adenosine triphosphate (ATP) infusion in patients wit h suspected coronary artery disease. Background. Both ATP and adenosin e are potent coronary vasodilators with a very short half-life. Severa l studies have confirmed that the diagnostic accuracy of adenosine tha llium-201 scintigraphy is comparable to that with exercise. However, a high incidence of side effects, including atrioventricular (AV) block , has also been reported. Because the appropriate infusion rate for AT P has not Set been determined, this agent has not been tested in combi nation with myocardial scintigraphy. Methods. The study group included 253 consecutive patients who underwent thallium-201 myocardial tomogr aphy with ATP infusion (0.16 mg/kg body weight per min for 5 min). The occurrence of adverse effects was carefully monitored. Of the 120 pat ients with coronary angiography, 76 had significant coronary artery di sease. Tomographic images were assessed visually and by computer-quant ified polar maps, and they were compared with the results of coronary angiography. Results. Although 56% of the patients had some adverse ef fects, they were transient and mild. In all patients, the ATP infusion protocol could be completed, and no patient required aminophylline; A V block occurred in only 2% of the patients. The sensitivity and speci ficity were 88% and 80%, respectively, by visual analysis and 91%: and 86%, respectively, by computer quantification. Conclusions. Thallium tomography,vith ATP is feasible and has a diagnostic value similar to that with adenosine for detecting coronary artery disease. In addition , it may have fewer side effects than adenosine myocardial tomography.