Identification of viable myocardium in patients with chronic coronary artery disease and left ventricular dysfunction. Comparison of thallium scintigraphy with reinjection and PET imaging with 18F-fluorodeoxyglucose.

摘要: In patients with chronic coronary artery disease and left ventricular dysfunction, the distinction between dysfunction arising from myocardial fibrosis ischemic, but viable, myocardium has important clinical implications. By positron emission tomography (PET), enhanced fluorine-18-labeled fluorodeoxyglucose (FDG) uptake in segments impaired function reduced blood flow is evidence of viability. Reinjection thallium-201 at rest immediately after stress-redistribution imaging may also provide viability by demonstrating thallium regions apparently "irreversible" defects. To compare these two methods, we studied 16 (ejection fraction, 27 +/- 9%), all whom had irreversible defects on standard exercise-redistribution single-photon computed (SPECT) imaging. Thallium was reinjected redistribution study, SPECT images were reacquired. The underwent PET FDG oxygen-15-labeled water. A total 432 analyzed comparable transaxial tomograms, which 166 (38%) before reinjection. demonstrated 121 (73%) Irreversible then subgrouped according to degree activity, relative peak activity normal regions. only mild (60-85% activity) or moderate (50-59% peak) reduction considered viable basis 91% 84% segments, respectively. contrast, severe (less than 50% peak), present 51% segments. such defects, an identical number (51%) data concordant techniques 88% 45% identified as 43% scar both reinjection studies. These observations suggest that can be used identify dysfunction. Most represent confirmed uptake.(ABSTRACT TRUNCATED AT 400 WORDS)