Thallium-201 Myocardial Imaging in Patients with Coronary Artery Disease: Comparison of Intravenous Adenosine and Oral Dipyridamole

OBJECTIVE:To compare thallium-201 (201Tl) myocardial perfusion imaging following intravenous adenosine and oral dipyridamole.DESIGN:Open-label, randomized, comparison.SETTING:Outpatient, university-affiliated clinic.PATIENTS:Fifteen patients with angiographically documented coronary artery disease.INTERVENTIONS:Planar 201Tl myocardial perfusion imaging following both intravenous adenosine 140 μg/kg/min for six minutes and oral dipyridamole suspension 300 mg.MAIN OUTCOME MEASURES:A comparison between adenosine and dipyridamole was made in the following areas: concordance in interpretation of 201Tl scintigrams, cardiac and noncardiac 201Tl uptake and clearance, hemodynamic and electrocardiographic changes, and adverse effects.RESULTS:The scintigraphic studies showed perfusion defects in 13 patients (87 percent) after dipyridamole and in 15 patients (100 percent) after adenosine. 201Tl uptake and clearance were quantitated in nine myocardial segments and in four extracardiac segments in each patient. 201Tl u...