BACKGROUND Complications of transcatheter aortic valve implantation(TAVI)procedures include bleeding,vascular complications,and strokes.These complications are often associated with the type of access used.The two typ...BACKGROUND Complications of transcatheter aortic valve implantation(TAVI)procedures include bleeding,vascular complications,and strokes.These complications are often associated with the type of access used.The two types of access in TAVI procedures are primary and secondary.The main use of the primary access is for valve delivery,while secondary access is used for angiography and hemodynamic monitoring.While there are many options for primary access,those for secondary access are transfemoral and transradial.AIM To compare outcomes between transradial vs transfemoral secondary access(TFSA).METHODS A systematic search was conducted using major databases(EMBASE,PubMed,Cochrane Central,Google Scholar),which resulted in 5 studies that met the criteria for study selection.Outcomes of interest were 30-d rates each of major/life-threatening bleeding,vascular complications,strokes,and mortality.All 5 studies were observational.Only adjusted or matched data were used when available in this meta-analysis.RESULTS A total of 5065 patients underwent TAVI,with 1453 patients(28.7%)having undergone transradial secondary access(TRSA)and 3612 patients(71.3%)TFSA.Irrespective of the site of primary access,the odds of having major or lifethreatening bleeding were 60%lower in the TRSA group than the TFSA group(P<0.00001).The odds of having major vascular complications were 52%lower in the TRSA group(P<0.0001)with no difference in minor vascular complications between the 2 groups.Similarly,the odds of mortality in 30-d after the procedure were 41%lower(P=0.006)and the odds of stroke were 54%lower(P=0.001)in the TRSA group than the TFSA group.CONCLUSION The transradial secondary approach appears to be a safer alternative to the transfemoral secondary approach in TAVI procedures.展开更多
Since FCC's opening for white space(WS) utilization,database-assisted dynamic spectrum access(DSA) has become the de facto solution for the realization of dynamic spectrum sharing(DSS),due to its simplicity and co...Since FCC's opening for white space(WS) utilization,database-assisted dynamic spectrum access(DSA) has become the de facto solution for the realization of dynamic spectrum sharing(DSS),due to its simplicity and compatibility with commercial off-the-shelf(COTS) devices.It is envisioned that such technology will strongly support the prosperous wireless multimedia networking(WMN) applications with satisfying QoS guarantees in the future.However,how to counter the time-frequency variant property when exploiting the WS spectrum for the provision of these services to secondary users(SUs) still remains a great challenge.In such context,a dynamic secondary access scheme for database-assisted spectrum sharing networks is proposed in this paper.In the beginning,the spectrum requirements of SUs for diverse services are modeled by considering the minimum required service data-rate and spectrum access duration.Afterwards,the spectrum demand evaluation and bidding policy are formulated based on the service classes of SUs.Furthermore,a doublephase(DP) spectrum allocation scheme,which consists of the initial resource allocation phase and resource allocation adjustment phase,is carefully designed for DSA.Finally,extensive simulations are conducted and the results demonstrate that our scheme can increase the spectrum trading revenue and adapt to varying service requirements.展开更多
文摘BACKGROUND Complications of transcatheter aortic valve implantation(TAVI)procedures include bleeding,vascular complications,and strokes.These complications are often associated with the type of access used.The two types of access in TAVI procedures are primary and secondary.The main use of the primary access is for valve delivery,while secondary access is used for angiography and hemodynamic monitoring.While there are many options for primary access,those for secondary access are transfemoral and transradial.AIM To compare outcomes between transradial vs transfemoral secondary access(TFSA).METHODS A systematic search was conducted using major databases(EMBASE,PubMed,Cochrane Central,Google Scholar),which resulted in 5 studies that met the criteria for study selection.Outcomes of interest were 30-d rates each of major/life-threatening bleeding,vascular complications,strokes,and mortality.All 5 studies were observational.Only adjusted or matched data were used when available in this meta-analysis.RESULTS A total of 5065 patients underwent TAVI,with 1453 patients(28.7%)having undergone transradial secondary access(TRSA)and 3612 patients(71.3%)TFSA.Irrespective of the site of primary access,the odds of having major or lifethreatening bleeding were 60%lower in the TRSA group than the TFSA group(P<0.00001).The odds of having major vascular complications were 52%lower in the TRSA group(P<0.0001)with no difference in minor vascular complications between the 2 groups.Similarly,the odds of mortality in 30-d after the procedure were 41%lower(P=0.006)and the odds of stroke were 54%lower(P=0.001)in the TRSA group than the TFSA group.CONCLUSION The transradial secondary approach appears to be a safer alternative to the transfemoral secondary approach in TAVI procedures.
基金supported in part by Major State Basic Research Development Program of China(973 Program)(No.2009CB320403)National Natural Science Foundation of China(61420106008,61221001, 61201222,61100213)+5 种基金the 111 Project (B07022)China Scholarship CouncilShanghai Key Laboratory of Digital Media Processing and Transmissionsthe funds of MIIT of China(Grant No.2011ZX03001-007-03)Research Grant SRG030-FST13-HF from the University of Macaothe NSERC,Canada
文摘Since FCC's opening for white space(WS) utilization,database-assisted dynamic spectrum access(DSA) has become the de facto solution for the realization of dynamic spectrum sharing(DSS),due to its simplicity and compatibility with commercial off-the-shelf(COTS) devices.It is envisioned that such technology will strongly support the prosperous wireless multimedia networking(WMN) applications with satisfying QoS guarantees in the future.However,how to counter the time-frequency variant property when exploiting the WS spectrum for the provision of these services to secondary users(SUs) still remains a great challenge.In such context,a dynamic secondary access scheme for database-assisted spectrum sharing networks is proposed in this paper.In the beginning,the spectrum requirements of SUs for diverse services are modeled by considering the minimum required service data-rate and spectrum access duration.Afterwards,the spectrum demand evaluation and bidding policy are formulated based on the service classes of SUs.Furthermore,a doublephase(DP) spectrum allocation scheme,which consists of the initial resource allocation phase and resource allocation adjustment phase,is carefully designed for DSA.Finally,extensive simulations are conducted and the results demonstrate that our scheme can increase the spectrum trading revenue and adapt to varying service requirements.
