Background Radiofrequency catheter ablation （RFCA） for atrial fibrillation （AF） has developed rapidly,and is a commonly performed ablation in many major hospitals throughout the world,due to its satisfactory resul...Background Radiofrequency catheter ablation （RFCA） for atrial fibrillation （AF） has developed rapidly,and is a commonly performed ablation in many major hospitals throughout the world,due to its satisfactory results.The aim of this study was to detect the effect of RFCA on C-reactive protein （CRP）,brain natriuretic peptide （BNP）,and echocardiograph in patients with persistent and permanent AF.Methods A total of 120 patients （71 males,mean age （50.8＆#177;12.0） years） with persistent and permanent AF undergoing RFCA under guidance of the Carto merge technique were studied.Left atrial diameter （LAD）,right atrial diameter （RAD）,left ventricular ejection fraction （LVEF）,CRP,and BNP were observed 3,6 and 12 months after RFCA and compared with results before RFCA.The recurrence of atrial arrhythmias was observed 3 and 12 months after the procedure.Results Compared with that before RFCA,LAD and RAD decreased and LVEF increased significantly after RFCA.Meanwhile,the levels of CRP and BNP were reduced significantly at 3,6,and 12 months after RFCA （P〈0.05）.In the non-recurrent patients,LVEF was increased significantly compared with the recurrent patients at 3,6,and 12 months after RFCA （P〈0.05）.CRP and BNP levels were decreased significantly in the non-recurrent patients compared with the recurrent patients at 3,6,and 12 months after RFCA （P〈0.05）.After one or two applications of RFCA,during a follow-up of 12 months,12 patients （10.0%） had AF,10 patients （8.3%） had atrial flutter,and 5 patients had atrial tachycardia （4.2%）.Conclusions Conversion of AF to sinus rhythm by RFCA,has been shown to reduce LA size and improve LVEF.It can also significantly decrease the levels of CRP and BNP in patients with persistent and permanent AF and reduce the risk of inflammation and developing heart failure.展开更多
The micro-ablation processes and morphological evolution of ablative craters on single-crystal magnesium under subpicosecond laser irradiation are investigated using molecular dynamics(MD) simulations and experiments....The micro-ablation processes and morphological evolution of ablative craters on single-crystal magnesium under subpicosecond laser irradiation are investigated using molecular dynamics(MD) simulations and experiments.The simulation results exhibit that the main failure mode of single-crystal Mg film irradiated by a low fluence and long pulse width laser is the ejection of surface atoms,which has laser-induced high stress.However,under high fluence and short pulse width laser irradiation,the main damage mechanism is nucleation fracture caused by stress wave reflection and superposition at the bottom of the film.In addition,Mg[0001] has higher pressure sensitivity and is more prone to ablation than Mg[0001].The evolution equation of crater depth is established using multi-pulse laser ablation simulation and verified by experiments.The results show that,under multiple pulsed laser irradiation,not only does the crater depth increase linearly with the pulse number,but also the quadratic term and constant term of the fitted crater profile curve increase linearly.展开更多
We investigate the influence of environmental media on ablation rate of AISI 443 stainless steel under femtosecond （fs） laser single raster scan and multiple raster scans in air, water, and methanol. Meanwhile, the ...We investigate the influence of environmental media on ablation rate of AISI 443 stainless steel under femtosecond （fs） laser single raster scan and multiple raster scans in air, water, and methanol. Meanwhile, the development of ablation rate with the change of fs laser-induced surface morphology in the three environmental media is comparatively studied. The results show that environmental media as well as fs laser-induced morphology control the ablation rate with the increasing number of raster scans （N）. Under single raster scanning （N = 1）, the ablation rate is higher in liquid than in air due to the confinement of plasma, laser-induced shockwaves, and bubble-related mechanical forces. However, under multiple raster scans, the variation in ablation rate with the increase in N in these three environmental media is complicated and is largely determined by the surface morphology induced by previous fs laser ablation. When N 〉 20, the ablation rate is much higher in air than in liquids due to preferential ablation caused by the formation of nanostructures-textured mound-shaped microstructures in air. Besides, the redeposition of ejected ablated materials is also an important factor that affects the ablation depth.展开更多
文摘Background Radiofrequency catheter ablation （RFCA） for atrial fibrillation （AF） has developed rapidly,and is a commonly performed ablation in many major hospitals throughout the world,due to its satisfactory results.The aim of this study was to detect the effect of RFCA on C-reactive protein （CRP）,brain natriuretic peptide （BNP）,and echocardiograph in patients with persistent and permanent AF.Methods A total of 120 patients （71 males,mean age （50.8＆#177;12.0） years） with persistent and permanent AF undergoing RFCA under guidance of the Carto merge technique were studied.Left atrial diameter （LAD）,right atrial diameter （RAD）,left ventricular ejection fraction （LVEF）,CRP,and BNP were observed 3,6 and 12 months after RFCA and compared with results before RFCA.The recurrence of atrial arrhythmias was observed 3 and 12 months after the procedure.Results Compared with that before RFCA,LAD and RAD decreased and LVEF increased significantly after RFCA.Meanwhile,the levels of CRP and BNP were reduced significantly at 3,6,and 12 months after RFCA （P〈0.05）.In the non-recurrent patients,LVEF was increased significantly compared with the recurrent patients at 3,6,and 12 months after RFCA （P〈0.05）.CRP and BNP levels were decreased significantly in the non-recurrent patients compared with the recurrent patients at 3,6,and 12 months after RFCA （P〈0.05）.After one or two applications of RFCA,during a follow-up of 12 months,12 patients （10.0%） had AF,10 patients （8.3%） had atrial flutter,and 5 patients had atrial tachycardia （4.2%）.Conclusions Conversion of AF to sinus rhythm by RFCA,has been shown to reduce LA size and improve LVEF.It can also significantly decrease the levels of CRP and BNP in patients with persistent and permanent AF and reduce the risk of inflammation and developing heart failure.
文摘The micro-ablation processes and morphological evolution of ablative craters on single-crystal magnesium under subpicosecond laser irradiation are investigated using molecular dynamics(MD) simulations and experiments.The simulation results exhibit that the main failure mode of single-crystal Mg film irradiated by a low fluence and long pulse width laser is the ejection of surface atoms,which has laser-induced high stress.However,under high fluence and short pulse width laser irradiation,the main damage mechanism is nucleation fracture caused by stress wave reflection and superposition at the bottom of the film.In addition,Mg[0001] has higher pressure sensitivity and is more prone to ablation than Mg[0001].The evolution equation of crater depth is established using multi-pulse laser ablation simulation and verified by experiments.The results show that,under multiple pulsed laser irradiation,not only does the crater depth increase linearly with the pulse number,but also the quadratic term and constant term of the fitted crater profile curve increase linearly.
基金supported by the National Natural Science Foundation of China under Grant No.51305292
文摘We investigate the influence of environmental media on ablation rate of AISI 443 stainless steel under femtosecond （fs） laser single raster scan and multiple raster scans in air, water, and methanol. Meanwhile, the development of ablation rate with the change of fs laser-induced surface morphology in the three environmental media is comparatively studied. The results show that environmental media as well as fs laser-induced morphology control the ablation rate with the increasing number of raster scans （N）. Under single raster scanning （N = 1）, the ablation rate is higher in liquid than in air due to the confinement of plasma, laser-induced shockwaves, and bubble-related mechanical forces. However, under multiple raster scans, the variation in ablation rate with the increase in N in these three environmental media is complicated and is largely determined by the surface morphology induced by previous fs laser ablation. When N 〉 20, the ablation rate is much higher in air than in liquids due to preferential ablation caused by the formation of nanostructures-textured mound-shaped microstructures in air. Besides, the redeposition of ejected ablated materials is also an important factor that affects the ablation depth.
