EVALUATION OF THE EFFICACY OF NICORANDIL IN PATIENTS WITH ISCHEMIC-HEART-DISEASE BY EXERCISE TL-201 MYOCARDIAL SPECT

The effect of nicorandil on myocardial perfusion in ischemic heart dis ease was studied using exercise-load T1-201 myocardial SPECT (Ex-SPECT ). ExSPECT was carried out in 12 patients with previous myocardial inf arction (OMI) and 9 with angina pectoris (AP) before and after adminis tration of nicorandil 15 mg/day, for three or more weeks; %T1 uptake a nd the washout rate in infarcted or ischemic areas were calculated fro m short axial images using the Bull's eye method. In the OMI group, %T 1 uptake and washout rates in the infarction areas improved significan tly from 52.4% and 0.25 before nicorandil to 60.4% and 0.38 after nico randil. In the AP group, too, %T1 uptake and washout rates showed a si gnificant improvement from 56.9% and 0.10 before to 69.1% and 0.33 aft er administration of nicorandil. Six subjects who had not received the drug, and who showed negative washout rates, had high improvement rat es when nicorandil was administered, suggesting that the drug could in crease myocardial perfusion during exercise loading as well as suppres sing coronary spasm. Ex-SPECT was carried out in 4 subjects before and after the administration of nicarandil and after subsequent surgical treatment (PTCA or CABG) and the effects of the two therapies were com pared. The washout rate was improved from 0.01 to 0.34 by the administ ration of nicorandil, and a notable increase in coronary artery blood flow was achieved compared to the level after surgical treatment, i.e. 0.50. It is concluded that normal dosages of nicorandil have a powerf ul direct effect of dilating the coronary arteries without any influen ce on preload or afterload.