Prospective evaluation of health status, quality of life and clinical outcomes following implantable defibrillator generator exchange

BACKGROUND Little is known about health status and quality of life(QoL)after implantable cardioverter-defibrillator(ICD)generator exchange(GE).METHODS We prospectively followed patients undergoing first-time ICD GE.Serial assessments of health status were performed by administering the 36-Item Short Form Survey(SF-36).RESULTS Mean age was 67.5±14.3 years,left ventricle ejection fraction(LVEF)was 36.5%±15.0%and over 40%of the cohort had improved LVEF to>35%at the time of GE.SF-36 scores were significantly worse in physical/general health domains compared to domains of emotional/social well-being(P<0.001 for each comparison).Physical health scores were significantly worse among those with medical comorbidities including diabetes,chronic obstructive pulmonary disease and atrial fibrillation.Mean follow-up was 1.6±0.5 years after GE.Overall SF-36 scores remained stable across all domains during follow-up.Survival at 3 years post-GE was estimated at 80%.Five patients died during follow-up and most deaths were adjudicated as non-arrhythmic in origin.Four patients experienced appropriate ICD shocks after GE,three of whom had LVEF which remains impaired LVEF(i.e.,<35%)at the time of GE.CONCLUSION Patients undergoing ICD GE have significantly worse physical health compared to emotional/social well-being,which is associated with the presence of medical comorbidities.In terms of clinical outcomes,the incidence of appropriate shocks after GE among those with improvement in LVEF is very low,and most deaths post-procedure appear to be non-arrhythmic in origin.These data represent an attempt to more fully characterize the spectrum of QoL and clinical outcomes after GE.

Investigation of Possible Half-Metallic Antiferromagnets on Double Perovskites A_(2)BB′O_(6)(A=Ca,Sr Ba;B,B′=Transition Metal Elements)

A search was made for possible half-metallic(HM)antiferromagnet(AFM)in all the(C_(2)^(92)=406)double perovskites structures of Sr2BB′O6 where BB′pairs are any combination of 3d,4d or 5d transition elements with the exception of La.Sr can also be replaced by Ca or Ba whenever HM-AFM was found and similar calculations were then performed in order to probe further possibilities.It was found that A_(2)MoOsO_(6),A_(2)TcReO_(6),A_(2)CrRuO_(6),where A=Ca,Sr,Ba,are all potential candidates for HM-AFM.The AFM of A2BB′O6 comes from both the superexchange mechanism and the generalized double exchange mechanism via the B(t2g)-O2pp-B′(t2g)coupling,With the latter also being the origin of their HM.Also considered were the effects of spin-orbit coupling(SOC)and correlation(+U)by introducing+SOC and+U corrections.It is found that the SOC effect has much less influence than the correlation effect on the HMproperty of the compounds.For A_(2)TcReO_(6)and A_(2)CrRuO_(6),after+U,they become nearlyMott-Insulators.In the future,it is hoped that therewill be further experimental confirmation for these possible HM-AFMcandidates.