technetium-tc-99m-tetrofosmin and Cerebral-Infarction

It is well known that silent myocardial ischemia (SMI) often complicates patients with cerebral infarction and that stroke patients often die of ischemic heart disease. Therefore, it is considered important to treat myocardial ischemia in stroke patients. This study investigated SMI complicating Japanese patients with fresh stroke, using (99m)Tc-tetrofosmin myocardial scintigraphy with pharmacologic stress testing to elucidate their clinical manifestations. This study included 41 patients (26 men, mean age 76.0 ± 10.7 years) with acute cerebral infarction and no history of coronary artery disease. All patients underwent (99m)Tc-tetrofosmin myocardial scintigraphy with intravenous administration of adenosine to diagnose SMI. Of the 41 patients, myocardial ischemia was confirmed in 17 patients (41.5%). Atherosclerotic etiology was the major cause of stroke in the ischemia(+) group and embolic origin was the major cause in the ischemia(-) group. Patients with myocardial ischemia had a higher incidence of diabetes mellitus (52.9 vs 20.8%; P = 0.0323) and more than two conventional cardiovascular risk factors (64.7 vs 25.0%; P = 0.0110) compared with the nonischemic patients. Infarction subtype of atherosclerotic origin was an independent positive predictor of asymptomatic myocardial ischemia in patients with stroke. These findings indicate that the prevalence of asymptomatic myocardial ischemia is relatively high, especially in patients with stroke of atherosclerotic origin. Therefore, it is beneficial for us to narrow the target population who are at the highest risk when screening for SMI in Japanese patients with acute cerebral infarction.

Topics: Acute Disease; Adenosine; Aged; Cerebral Infarction; Coronary Angiography; Diagnosis, Differential; Exercise Test; Female; Follow-Up Studies; Humans; Incidence; Japan; Male; Myocardial Ischemia; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Retrospective Studies; Risk Factors; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents

To investigate the role of sublingual nitrate plus 99Tcm-tetrofosmin infusion in the detection of severely ischaemic but viable myocardium, we selected 25 patients with coronary artery disease who had at least one fixed segmental defect during conventional stress-redistribution (ST-RD) 201Tl single photon emission tomographic (SPET) imaging. Reinjection (RI) and 24 h late redistribution (LRD) imaging were also performed. Within a week of 201Tl imaging, one-day rest-stress (R-ST) 99Tcm-tetrofosmin SPET was performed with the same stress levels. The following day, 99Tcm-tetrofosmin was infused over 1 h immediately after sublingual nitrate administration and SPET images (N + Inf) were acquired. Of 100 fixed defects on R-ST 99Tcm-tetrofosmin imaging, 15 were reversible on N + Inf 99Tcm-tetrofosmin imaging. There was 91% concordance between ST-RD/RI/LRD 201Tl and R-ST/N + Inf 99Tcm-tetrofosmin imaging regarding reversibility. We conclude that N + Inf 99Tcm-tetrofosmin imaging may be clinically useful in the detection of severely ischaemic but viable myocardium.

Topics: Administration, Sublingual; Adult; Aged; Cerebral Infarction; Coronary Disease; Exercise Test; Female; Heart; Humans; Infusions, Intravenous; Male; Middle Aged; Myocardial Ischemia; Nitrates; Organophosphorus Compounds; Organotechnetium Compounds; Physical Exertion; Radiopharmaceuticals; Thallium Radioisotopes; Tissue Distribution; Tomography, Emission-Computed