AIM: To investigate endothelium-dependent and independent coronary microvascular functions in patients with vasospastic angina (VSA). METHODS: Thirty-six patients with VSA (30 men and 6 women; mean age, 58 years) were...AIM: To investigate endothelium-dependent and independent coronary microvascular functions in patients with vasospastic angina (VSA). METHODS: Thirty-six patients with VSA (30 men and 6 women; mean age, 58 years) were enrolled in this study. VSA was defined as ≥ 90% narrowing of the epicardial coronary arteries on angiography performed during a spasm provocation test, presence of chest pain, and/or ST-segment deviation on an electrocardiogram (ECG). Patients (n = 36) with negative spasm provocation test results and those matched for age and sex were enrolled as a control group (nonVSA group). Low-dose acetylcholine (ACh; 3 μg/min) was infused into the left coronary ostium for 2 min during the spasm provocation test. Following the spasm provocation test, nitroglycerin (0.2 mg) was administered intracoronally. Coronary blood flow (was calculated from quantitativeangiography and Doppler flow velocity measurements, and the coronary flow reserve was calculated as the ratio of coronary flow velocity after injection of adenosine triphosphate (20 μg) to the baseline value. Changes in the coronary artery diameter in response to ACh and nitroglycerin infusion were expressed as percentage changes from baseline measurements. RESULTS: Body mass index was significantly lower in the VSA group than in the nonVSA group. The fre- quency of conventional coronary risk factors and the rate of statin use were similar between the 2 groups. The left ventricular ejection fraction as evaluated by echocardiography was similar between the 2 groups. The duration of angina was 9 ± 2 mo. The results of blood chemistry analysis were similar between the 2 groups. Low-dose ACh did not cause coronary spasms. The change in coronary artery diameter in response to ACh was lower in the VSA group (-1.4% ± 9.3%) than in the nonVSA group (3.1% ± 6.5%, P 【 0.05), whereas nitroglycerin-induced coronary artery dilatation and coronary blood flow increase in response to ACh or coronary flow reserve did not differ significantly between the 2 groups. CONCLUSION: These findings suggest that microvascular coronary function may be preserved despite endothelial dysfunction of the epicardial coronary arteries in patients with VSA.展开更多
AIM: To investigate the effects of different doses of aspirin on coronary endothelial function. METHODS: The study included 139 Japanese subjects(mean age, 60 years; 53 women) with angiographically normal coronary art...AIM: To investigate the effects of different doses of aspirin on coronary endothelial function. METHODS: The study included 139 Japanese subjects(mean age, 60 years; 53 women) with angiographically normal coronary arteries. Patients were distributed into GroupⅠ(n = 63), who was administered aspirin and Group Ⅱ(n = 76), the control, who were not administered aspirin. GroupⅠwas further divided into GroupⅠa(n = 50, low-dose aspirin, 100 mg) and GroupⅠb(n = 13, high-dose aspirin, 500 mg). After a routine coronary angiography, acetylcholine(ACh; 3 and 30 μg/min successively) and nitroglycerin(NTG) were infused into the left coronary ostium over 2 min. The change in the diameter of the coronary artery in response to each drug was expressed as the percentage change from baseline values.RESULTS: The patient characteristics did not differ between the two groups. The change in coronary diameter in response to ACh was greater in GroupⅠthan in Group Ⅱ(P = 0.0043), although the NTG-induced coronary vasodilation was similar between groups. ACh-induced dilation was greater in GroupⅠa than in GroupⅠb(P = 0.0231). Multivariate regression analysis showed that a low-dose of aspirin(P = 0.0004) was one of the factors associated with ACh-induced dilation at 30 μg/min.CONCLUSION: In subjects with angiographically normal coronary arteries, aspirin only had a positive influence on coronary endothelial function at the low dose of 100 mg. This improvement of coronary endothelial function may be involved in the preventive effect of aspirin against future coronary events.展开更多
The purpose of this research is to propose an early restoration for lifeline systems after earthquake disasters. The previous researches show that the optimization of the restoration schedule by using genetic algorith...The purpose of this research is to propose an early restoration for lifeline systems after earthquake disasters. The previous researches show that the optimization of the restoration schedule by using genetic algorithm (GA) is powerful. However, those are not considering the uncertain environment after earthquake disasters. The circumstances of the damage at devastated areas are very changeable due to the aftershock, fire disaster and bad weather. In addition, the restoring works may delay by unexpected accidents. Therefore, it is necessary to obtain the restoration schedule which has robustness, because the actual restoring works could not progress smoothly under the uncertain environment. GA considering uncertainty (GACU) can treat various uncertainties involved, but it is difficult to obtain the robust schedule. In this study, an attempt is made to develop a decision support system of the optimal restoration scheduling by using the improved GACU.展开更多
文摘AIM: To investigate endothelium-dependent and independent coronary microvascular functions in patients with vasospastic angina (VSA). METHODS: Thirty-six patients with VSA (30 men and 6 women; mean age, 58 years) were enrolled in this study. VSA was defined as ≥ 90% narrowing of the epicardial coronary arteries on angiography performed during a spasm provocation test, presence of chest pain, and/or ST-segment deviation on an electrocardiogram (ECG). Patients (n = 36) with negative spasm provocation test results and those matched for age and sex were enrolled as a control group (nonVSA group). Low-dose acetylcholine (ACh; 3 μg/min) was infused into the left coronary ostium for 2 min during the spasm provocation test. Following the spasm provocation test, nitroglycerin (0.2 mg) was administered intracoronally. Coronary blood flow (was calculated from quantitativeangiography and Doppler flow velocity measurements, and the coronary flow reserve was calculated as the ratio of coronary flow velocity after injection of adenosine triphosphate (20 μg) to the baseline value. Changes in the coronary artery diameter in response to ACh and nitroglycerin infusion were expressed as percentage changes from baseline measurements. RESULTS: Body mass index was significantly lower in the VSA group than in the nonVSA group. The fre- quency of conventional coronary risk factors and the rate of statin use were similar between the 2 groups. The left ventricular ejection fraction as evaluated by echocardiography was similar between the 2 groups. The duration of angina was 9 ± 2 mo. The results of blood chemistry analysis were similar between the 2 groups. Low-dose ACh did not cause coronary spasms. The change in coronary artery diameter in response to ACh was lower in the VSA group (-1.4% ± 9.3%) than in the nonVSA group (3.1% ± 6.5%, P 【 0.05), whereas nitroglycerin-induced coronary artery dilatation and coronary blood flow increase in response to ACh or coronary flow reserve did not differ significantly between the 2 groups. CONCLUSION: These findings suggest that microvascular coronary function may be preserved despite endothelial dysfunction of the epicardial coronary arteries in patients with VSA.
文摘AIM: To investigate the effects of different doses of aspirin on coronary endothelial function. METHODS: The study included 139 Japanese subjects(mean age, 60 years; 53 women) with angiographically normal coronary arteries. Patients were distributed into GroupⅠ(n = 63), who was administered aspirin and Group Ⅱ(n = 76), the control, who were not administered aspirin. GroupⅠwas further divided into GroupⅠa(n = 50, low-dose aspirin, 100 mg) and GroupⅠb(n = 13, high-dose aspirin, 500 mg). After a routine coronary angiography, acetylcholine(ACh; 3 and 30 μg/min successively) and nitroglycerin(NTG) were infused into the left coronary ostium over 2 min. The change in the diameter of the coronary artery in response to each drug was expressed as the percentage change from baseline values.RESULTS: The patient characteristics did not differ between the two groups. The change in coronary diameter in response to ACh was greater in GroupⅠthan in Group Ⅱ(P = 0.0043), although the NTG-induced coronary vasodilation was similar between groups. ACh-induced dilation was greater in GroupⅠa than in GroupⅠb(P = 0.0231). Multivariate regression analysis showed that a low-dose of aspirin(P = 0.0004) was one of the factors associated with ACh-induced dilation at 30 μg/min.CONCLUSION: In subjects with angiographically normal coronary arteries, aspirin only had a positive influence on coronary endothelial function at the low dose of 100 mg. This improvement of coronary endothelial function may be involved in the preventive effect of aspirin against future coronary events.
文摘The purpose of this research is to propose an early restoration for lifeline systems after earthquake disasters. The previous researches show that the optimization of the restoration schedule by using genetic algorithm (GA) is powerful. However, those are not considering the uncertain environment after earthquake disasters. The circumstances of the damage at devastated areas are very changeable due to the aftershock, fire disaster and bad weather. In addition, the restoring works may delay by unexpected accidents. Therefore, it is necessary to obtain the restoration schedule which has robustness, because the actual restoring works could not progress smoothly under the uncertain environment. GA considering uncertainty (GACU) can treat various uncertainties involved, but it is difficult to obtain the robust schedule. In this study, an attempt is made to develop a decision support system of the optimal restoration scheduling by using the improved GACU.