Background The Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery （SYNTAX）-score is a validated tool for risk stratification and revascularization strategy selection in patients with c...Background The Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery （SYNTAX）-score is a validated tool for risk stratification and revascularization strategy selection in patients with complex coronary artery disease. The aim of this study was to analyse its age-related prognostic value. Methods SYNTAX-score was calculated in 1331 all-comer patients undergoing percutaneous coronary intervention （PCI）： 463 patients ≥ 75 years and 868 patients 〈 75 years. Outcomes of interest were all-cause mortality at one and two years. Results A significant interaction of age and SYNTAX-score for mortality was observed at two-year （Pinteraction= 0.019） but not at one-year follow-up （Pinteraction= 0.594）. In multivariable analysis, SYNTAX-score independently predicted 1-year mortality in both age groups （〈 75 years, hazard ratio （HR）： 1.43, 95% confidence intervals （CI）： 1.03-2.00, P = 0.034; and 〉 75 years, HR： 1.37, 95% CI： 1.01-1.85, P = 0.042）, but only two-year mortality among younger patients （〈 75 years, HR： 1.33, 95% CI： 1.01-1.76, P = 0.041; and ≥ 75 years, HR： 1.11, 95% CI： 0.87-1.41, P = 0.394）. SYNTAX-score tertiles were useful to stratify 1-year mortality in both, patients 〈 75 years （SYNTAX-score 〈 9, 3.8%; 9-20, 5.3%; 〉 20, 10.3%; P = 0.004） and 〉 75 years （SYNTAX-score 〈 11, 5.7%; 11-22.5, 16.1%; 〉 22.5, 18.7%; P = 0.003）, but two-year mortality only among patients 〈 75 years （SYNTAX-score 〈 9, 6.5%; 9-20, 7.6%; ≥ 20, 15%; P 〈 0.001） and not among ≥ 75 years old patients （SYNTAX-score 〈 11, 19.4%; 11-22.5, 26.3%; _〉 22.5, 27.9%; P = 0.138）. Conclusions Age modi- fies the impact of the SYNTAX-score on longer-term mortality after PCI. Among patients 〈 75 years, the SYNTAX-score independently predicts the risk of death at one and two years after PCI, while among patients 〉 75 years its predictive role is limited to the first year after PCI. Further studies are needed to evaluate the value of SYNTAX-score for selecting the most appropriate revascularization strategy among elderly patients.展开更多
AC / DC converter is a kind of devices applicable to reactive power compensation. Three parameters including losses, Total Harmonic Distortion （THD） and compensation capacity have important role in designing procedu...AC / DC converter is a kind of devices applicable to reactive power compensation. Three parameters including losses, Total Harmonic Distortion （THD） and compensation capacity have important role in designing procedure that these parameters are affected by the firing angle. Consideration trade of between these parameters can cause be selected suitable firing angle for optimal working of the compensator. In this paper is defined an objective function which includes the above parameters. This objective function is optimized through appropriate weighting factor for any parameters and the optimal firing angle will be obtained. So, the mention parameters can be selected optimally.展开更多
文摘Background The Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery （SYNTAX）-score is a validated tool for risk stratification and revascularization strategy selection in patients with complex coronary artery disease. The aim of this study was to analyse its age-related prognostic value. Methods SYNTAX-score was calculated in 1331 all-comer patients undergoing percutaneous coronary intervention （PCI）： 463 patients ≥ 75 years and 868 patients 〈 75 years. Outcomes of interest were all-cause mortality at one and two years. Results A significant interaction of age and SYNTAX-score for mortality was observed at two-year （Pinteraction= 0.019） but not at one-year follow-up （Pinteraction= 0.594）. In multivariable analysis, SYNTAX-score independently predicted 1-year mortality in both age groups （〈 75 years, hazard ratio （HR）： 1.43, 95% confidence intervals （CI）： 1.03-2.00, P = 0.034; and 〉 75 years, HR： 1.37, 95% CI： 1.01-1.85, P = 0.042）, but only two-year mortality among younger patients （〈 75 years, HR： 1.33, 95% CI： 1.01-1.76, P = 0.041; and ≥ 75 years, HR： 1.11, 95% CI： 0.87-1.41, P = 0.394）. SYNTAX-score tertiles were useful to stratify 1-year mortality in both, patients 〈 75 years （SYNTAX-score 〈 9, 3.8%; 9-20, 5.3%; 〉 20, 10.3%; P = 0.004） and 〉 75 years （SYNTAX-score 〈 11, 5.7%; 11-22.5, 16.1%; 〉 22.5, 18.7%; P = 0.003）, but two-year mortality only among patients 〈 75 years （SYNTAX-score 〈 9, 6.5%; 9-20, 7.6%; ≥ 20, 15%; P 〈 0.001） and not among ≥ 75 years old patients （SYNTAX-score 〈 11, 19.4%; 11-22.5, 26.3%; _〉 22.5, 27.9%; P = 0.138）. Conclusions Age modi- fies the impact of the SYNTAX-score on longer-term mortality after PCI. Among patients 〈 75 years, the SYNTAX-score independently predicts the risk of death at one and two years after PCI, while among patients 〉 75 years its predictive role is limited to the first year after PCI. Further studies are needed to evaluate the value of SYNTAX-score for selecting the most appropriate revascularization strategy among elderly patients.
文摘AC / DC converter is a kind of devices applicable to reactive power compensation. Three parameters including losses, Total Harmonic Distortion （THD） and compensation capacity have important role in designing procedure that these parameters are affected by the firing angle. Consideration trade of between these parameters can cause be selected suitable firing angle for optimal working of the compensator. In this paper is defined an objective function which includes the above parameters. This objective function is optimized through appropriate weighting factor for any parameters and the optimal firing angle will be obtained. So, the mention parameters can be selected optimally.
