Clinical characteristics of silent myocardial ischemia diagnosed with adenosine stress 99mTc-tetrofosmin myocardial scintigraphy in Japanese patients with acute 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 Tc-99m-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 Tc-99m-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.