Dynamic planar myocardial perfusion imaging in patients with one-vessel disease with intracoronary injection of technetium 99m teboroxime during papaverine-induced coronary hyperemia

This study examined the imaging results and kinetics of technetium 99m teboroxime after its intracoronary injection during papaverine-induced coronary hyperemia in patients with one-vessel disease before and after coronary angioplasty. Thirteen patients with ≥90% diameter stenosis of either the left anterior descending or the left circumflex coronary artery were included. Two patients were excluded because of ventricular tachycardia during papaverine injection in one patient and unsuccessful angioplasty in the second patient. One mCi of technetium 99m teboroxime was injected into the left main coronary artery during coronary hyperemia induced by intracoronary injection of papaverine. Dynamic acquisition in a frame mode (20 sec/frame) was performed for 5 minutes in the left anterior oblique projection with a multicrystal gamma camera before and after successful angioplasty. Ischemic:normal count ratio increased from 0.75 ± 0.4 before to 1.00 ± 0.50 after angioplasty (p < 0.1). The of teboroxime was 6.5 ± 1.5 min in the normal zone and 7.2 ± 1.9 min in the ischemic zone (p, NS). Perfusion defects were visible in the territory of the stenosed coronary artery in 9 of 11 patients before angioplasty and in 7 of 11 patients after angioplasty. The image quality was excellent in all studies. Thus this study shows that performing dynamic imaging with intracoronary injection of technetium 99m teboroxime is feasible. This technique may be useful to study the impact of angioplasty on coronary flow and tracer kinetics.