Background Aortic valve stenosis （AS） is very common in the elderly patients above 80 years. Transcatheter aortic valve replacement （TAVR） in such patients is being increasingly performed. This study sought to ass...Background Aortic valve stenosis （AS） is very common in the elderly patients above 80 years. Transcatheter aortic valve replacement （TAVR） in such patients is being increasingly performed. This study sought to assess in-hospital outcome differences between octogenarians and nonagenarians and predictors of mortality in nonagenarians undergoing TAVR with severe AS. Method The study population was derived from the National Inpatient Sample （MS） for the years 2012-2014 using ICD-9 CM procedure codes 35.05 and 35.06 for TAVR. Hospitalizations below 80 years of age were excluded. After performing propensity score matching （1： 2）, in-hospital outcomes were compared in matched cohorts. Then, multivariate model was developed to analyze predictors of in-hospital mortality in nonagenarians. Results There were 11,630 hospitalizations in the octogenarian and 5815 hospitalizations in the nonagenarian group. Primary outcome of in-hospital mortality （6% vs. 4.1%, P ≤ 0.001） was higher in nonagenarians compared to octogenarians. Secondary outcomes including stroke （3.4% vs. 2.8%, P ≤ 0.001）, renal failure （18.9% vs. 17.3%, P ≤0.001）, blood transfusion （35% vs. 32.6%, P ≤ 0.001）, vascular complications （4.5% vs. 3.5%, P ≤ 0.001）, and pacemaker implantation （27.8% vs. 24.8%, P ≤ 0.001） were higher in nonagenarians. There was no difference in their length of stay. Median cost （70,3745 vs. 65,3815, P ≤ 0.001） was slightly higher with nonagenarian. Conclusions Although in-hospital mortality is slightly higher in nonagenarians, it is acceptable. This difference in mortality is at least partly explained by higher complications in nonagenarians. Efforts should be made to decrease the complications which can further narrow the difference in in-hospital mortality between the groups.展开更多
Rheumatoid arthritis (RA) is a systemic disorder that is chronic in nature and difficult to treat. RA presents in many variants. Here we present an interesting case only seldom described before. Our patient presented ...Rheumatoid arthritis (RA) is a systemic disorder that is chronic in nature and difficult to treat. RA presents in many variants. Here we present an interesting case only seldom described before. Our patient presented to emergency room with acute shortness of breath and was seen to have acute pulmonary edema. Patient later had urgent echocardiography which revealed severe mitral regurgitation from ruptured anterior leaflet. Patient was taken for heart valve replacement and was found to have RA nodule on ruptured leaflet. There are cases involving aortic valve but to our knowledge there are no reports of RA nodule on mitral leaflet.展开更多
A robust optimal framework is designed herein to mitigate the oscillatory dynamics in a doubly fed induction generator(DFIG)even in the presence of network disturbances and input variation.To address uncertain dynamic...A robust optimal framework is designed herein to mitigate the oscillatory dynamics in a doubly fed induction generator(DFIG)even in the presence of network disturbances and input variation.To address uncertain dynamics,herein,a novel transformation formula is developed for a wind energy conversion system.An unscented Kalman filter is applied to estimate the un-measured internal states of the wind energy conversion system using terminal measurements.The detailed convergence and stability analyses of the presented framework are investigated to validate its effectiveness.Additionally,comparative modal analyses are carried out to demonstrate the improvement in the damping of critical low-frequency oscillatory modes using the presented framework.The simulation results demonstrate satisfactory performance under various operating scenarios,such as increasing and decreasing wind speed and varying the terminal voltage.The comparative performance is demonstrated to validate the effectiveness of the presented framework over that of the state-of-the-art frameworks.展开更多
文摘Background Aortic valve stenosis （AS） is very common in the elderly patients above 80 years. Transcatheter aortic valve replacement （TAVR） in such patients is being increasingly performed. This study sought to assess in-hospital outcome differences between octogenarians and nonagenarians and predictors of mortality in nonagenarians undergoing TAVR with severe AS. Method The study population was derived from the National Inpatient Sample （MS） for the years 2012-2014 using ICD-9 CM procedure codes 35.05 and 35.06 for TAVR. Hospitalizations below 80 years of age were excluded. After performing propensity score matching （1： 2）, in-hospital outcomes were compared in matched cohorts. Then, multivariate model was developed to analyze predictors of in-hospital mortality in nonagenarians. Results There were 11,630 hospitalizations in the octogenarian and 5815 hospitalizations in the nonagenarian group. Primary outcome of in-hospital mortality （6% vs. 4.1%, P ≤ 0.001） was higher in nonagenarians compared to octogenarians. Secondary outcomes including stroke （3.4% vs. 2.8%, P ≤ 0.001）, renal failure （18.9% vs. 17.3%, P ≤0.001）, blood transfusion （35% vs. 32.6%, P ≤ 0.001）, vascular complications （4.5% vs. 3.5%, P ≤ 0.001）, and pacemaker implantation （27.8% vs. 24.8%, P ≤ 0.001） were higher in nonagenarians. There was no difference in their length of stay. Median cost （70,3745 vs. 65,3815, P ≤ 0.001） was slightly higher with nonagenarian. Conclusions Although in-hospital mortality is slightly higher in nonagenarians, it is acceptable. This difference in mortality is at least partly explained by higher complications in nonagenarians. Efforts should be made to decrease the complications which can further narrow the difference in in-hospital mortality between the groups.
文摘Rheumatoid arthritis (RA) is a systemic disorder that is chronic in nature and difficult to treat. RA presents in many variants. Here we present an interesting case only seldom described before. Our patient presented to emergency room with acute shortness of breath and was seen to have acute pulmonary edema. Patient later had urgent echocardiography which revealed severe mitral regurgitation from ruptured anterior leaflet. Patient was taken for heart valve replacement and was found to have RA nodule on ruptured leaflet. There are cases involving aortic valve but to our knowledge there are no reports of RA nodule on mitral leaflet.
基金supported in part by the National Natural Science Foundation of China(No.62103296)the UK Engineering and Physical Sciences Research Council(No.EP/T021713/1)the Shanxi Scholarship Council of China(No.2023-062).
文摘A robust optimal framework is designed herein to mitigate the oscillatory dynamics in a doubly fed induction generator(DFIG)even in the presence of network disturbances and input variation.To address uncertain dynamics,herein,a novel transformation formula is developed for a wind energy conversion system.An unscented Kalman filter is applied to estimate the un-measured internal states of the wind energy conversion system using terminal measurements.The detailed convergence and stability analyses of the presented framework are investigated to validate its effectiveness.Additionally,comparative modal analyses are carried out to demonstrate the improvement in the damping of critical low-frequency oscillatory modes using the presented framework.The simulation results demonstrate satisfactory performance under various operating scenarios,such as increasing and decreasing wind speed and varying the terminal voltage.The comparative performance is demonstrated to validate the effectiveness of the presented framework over that of the state-of-the-art frameworks.
