1.
Nicorandil administration shows cardioprotective effects in patients with poor TIMI and collateral flow as well as good flow after AMI.
Toyama, T, Seki, R, Hoshizaki, H, Kawaguchi, R, Isobe, N, Adachi, H, Oshima, S, Taniguchi, K, Kasama, S
Annals of nuclear medicine. 2006;(4):277-85
Abstract
BACKGROUND Nicorandil (NCR) has been reported to have cardioprotective effects in patients with AMI. And collateral flow and TIMI flow are also important determinants of final salvaged myocardium in patients with AMI. There is no evidence as to whether TIMI or collateral flow modifies the cardioprotective effects of NCR in patients with AMI. METHODS AND RESULTS We studied 68 initial AMI patients without restenosis which was defined as 50% diameter reduction of the intervention site in the chronic period. On initial CAG, 41 patients with poor flow (collateral: Rentrop 0 or 1 and TIMI 0 or 1) were NCR/Non-NCR = 20/21. Twenty-seven patients with good flow (collateral: Rentrop 2 or 3 or TIMI 2 or 3) were NCR/Non-NCR = 13/14. NCR was administered intravenously (4 mg) via intracoronary injection (2 mg) or continuously (4 mg/h). 99mTc-tetrofosmin (TF) and 123I-BMIPP SPECT were performed in the subacute and chronic (6 Mo) periods. In 20 SPECT segments, summed defect scores (TDS) and regional wall motion (WMS: -1=dyskinesis -4 = normal) of AMI segments using TF-QGS were estimated. In poor flow patients, the following values for NCR patients were higher (p < 0.05) than for Non-NCR patients in the improvement degree of TDS (BMIPP) (NCR: 6.5 +/- 3.9 vs. Non-NCR: 4.0 +/- 3.4), the improvement degree of TDS (TF) (NCR: 5.7 +/- 4.6 vs. Non-NCR: 2.2 +/- 4.6), and delta WMS (NCR: 1.4 +/- 1.1 vs. Non-NCR: 0.9 +/- 1.0). In good flow patients, the following values for NCR patients were better (p < 0.05) than for Non-NCR patients in TDS (BMIPP) (subacute) (NCR: 9.9 +/- 5.2 vs. Non-NCR: 16.5 +/- 10.4) and (chronic) (NCR: 5.1 +/- 5.2 vs. Non-NCR: 12.4 +/- 8.5), WMS (subacute) (NCR: 1.7 +/- 1.3 vs. Non-NCR: 1.0 +/- 1.0), and WMS (chronic) (NCR: 3.0 +/- 1.5 vs. Non-NCR: 2.1 +/- 1.3). CONCLUSION We conclude that the cardioprotective effects of nicorandil administration are observable in both AMI patients with poor collateral and TIMI flow and good flow before reperfusion therapy.
2.
Intravenous nicorandil can reduce the occurrence of ventricular fibrillation and QT dispersion in patients with successful coronary angioplasty in acute myocardial infarction.
Ueda, H, Nakayama, Y, Tsumura, K, Yoshimaru, K, Hayashi, T, Yoshikawa, J
The Canadian journal of cardiology. 2004;(6):625-9
Abstract
BACKGROUND Because nicorandil, a potassium channel opener, has a cardioprotective effect and attenuates reperfusion injury in patients with acute myocardial infarction (AMI), intravenous nicorandil should reduce arrhythmic mortality and QT dispersion in patients with AMI. OBJECTIVES The purpose of this study was to evaluate whether intravenous nicorandil reduces the occurrence of ventricular fibrillation and QT dispersion in patients with successful coronary angioplasty in AMI. METHODS A historical cohort study on the effect of nicorandil on ventricular fibrillation and QT dispersion was conducted. Eighty-three patients with AMI who underwent successful percutaneous transluminal coronary angioplasty (PTCA) were enrolled. The patients were divided into two groups: nicorandil (n=46) and control group (n=37). Nicorandil was injected at 4 mg/h continuously from admission to 48 h after PTCA in the nicorandil group. QT dispersion was measured before, immediately after, 24 h after and 48 h after PTCA. RESULTS Ventricular fibrillation was observed in three patients in the control group, but none was observed in the nicorandil group. QT dispersion in the nicorandil group was shorter than that in the control group 48 h after PTCA (QT dispersion was 23.2+/-16.1 ms and 33.4+/-24.0 ms, respectively, P<0.05). There was a significant difference between the two groups in time course after the onset of AMI (P<0.05). CONCLUSIONS Because intravenous nicorandil reduces the occurrence of ventricular fibrillation and QT dispersion in patients with successful coronary angioplasty in AMI, it would prevent the occurrence of cardiac events after successful PTCA for AMI.
3.
Nicorandil enhances myocardial tolerance to ischemia without progressive collateral recruitment during coronary angioplasty.
Sakai, K, Yamagata, T, Teragawa, H, Matsuura, H, Chayama, K
Circulation journal : official journal of the Japanese Circulation Society. 2002;(4):317-22
Abstract
Nicorandil, a hybrid nitrate and ATP-sensitive potassium channel opener, has had a preconditioning effect in some coronary angioplasty studies. The present study investigated whether the cardioprotective effects of nicorandil involve coronary collateral function. Thirty-two patients with stable angina pectoris were randomized to receive a 1-min intravenous infusion of nicorandil (100 microg/kg) or normal saline. Five minutes later they underwent three 2-min balloon inflations 5-min apart. The maximum ST-segment elevation (deltaSTmax), the sum of ST-segment elevations in all leads (sigmaST), and the chest pain score were determined at the end of each balloon inflation. The collateral flow index (CFI) was derived from simultaneous measurement of the mean aortic pressure and the coronary wedge pressure obtained from a pressure guidewire during balloon inflation. The deltaSTmax, sigmaST, and chest pain score decreased progressively during the 3 sequential balloon inflations in both groups, and the deltaSTmax and sigmaST were less in the nicorandil group than in the control group during each inflation. The CFI did not change during the 3 inflations in either group and was similar in the 2 groups during each inflation. In conclusion, pretreatment with intravenous nicorandil enhances myocardial tolerance to ischemia without progressive collateral recruitment during coronary angioplasty.