Patients with Ischemic Heart Disease

Background：Brain natriuretic peptide (BNP) is primarily secreted from the cardiac ventricles. Circulating concentrations of BNP are known to be increased in established chronic heart failure and acute myocardial infarction and to correlate well with left ventricular dysfunction and prognosis. It may also act as an index of ischemic severity. This study was performed in order to evaluate the value of plasma BNP measurement during exercise tests in patients with ischemic heart disease for an assessment of myocardial ischemia. Method：This study included a total of 63 cases of suspected ischemic heart disease or myocardial infarction. The subjects underwent treadmill exercise with a modified Bruce protocol. Tc-99m MIBI (methoxyisobutyl Isonitrile) SPECT image was obtained by one-day or two-day protocol with rest-stress sequence. They were divided into 3 groups by findings in exercise TC-99m MIBI SPECT；16 cases with reversible perfusion defect into the angina pectoris group, 12 cases with myocardial infarction and fixed perfusion defect into the myocardial infarction group and 35 cases without perfusion defect into the control group. Venous blood was obtained at rest and just after peak exercise. Plasma levels of BNP level were measured by radioimmunoassay. Result：BNP levels increased with exercise from 20.1±28.2 to 33.2±44.0 pg/ml in the control group, 33.9±48.8 to 44.6±49.2 pg/ml in the angina pectoris group and 86.6±85.0 to 140.9±116.2 pg/ml in the myocardial infarction group (p<0.01