简介:Epsilon波是致心律失常性右室心肌病的特征性心电图表现,发生机制是由于右室的部分心肌细胞萎缩、退化,被纤维或脂肪组织替代,右室病态的心肌细胞除极延迟,延迟的除极波即Epsilon波。但Epsilon波除见于致心律失常性右室心肌病以外,还可见于心脏结节病、先天性心脏病、右室心肌梗死、后壁心肌梗死以及其他右室受累的疾病。本文报道的一例食管癌患者经证实无右室心肌病变,其心电图上的Epsilon波考虑可能与右侧胸膜肥厚粘连、右侧液气胸,右心缘高密度影(疑为心包积液)有关,这些改变可以累及右室心外膜下的心肌细胞,使其发生除极延迟。
简介:BackgroundAtrialfibrillation(AF)isthemostcommonsustainedcardiacarrhythmiawithouteffectivetreatment.AFisassociatedwithatrialconductiondisturbancescausedbyelectricaland/orstructuralremodel-ing.Buttheroleofconnexin(Cx)43intheregulationofLtypecalciumchannel(LCC)remainsunclear.WehypothesizedthatCx43mightco-localizeandregulatetheLtypecalciumchannelcurrent(ICa,L).MethodsReal-timePCRandwhole-cellpatchclampwereusedtodetecttheexpressionofLCC1csubunitandthecurrentdensityofICa,L,beforeandafterCx43knockingdownrespectively.Theco-localizationofCx43withLCCwasinvestigatedbyco-immunoprecipitationandconfocalmicroscopy.ResultsKnockingdownofCx43significantlyinhibitedthecurrentdensityofICa,LthroughdecreasingthegeneexpressionofLCCα1cinculturedatrium-derivedmyocytes(HL-1cells).Cx43co-localizedwithLCCα1csubunitinatrialmyocytes.ConclusionsCx43regulatestheICa,LinatrialmyoctyesthroughLCC,representingapotentialpathogenicmechanisminatrialarrhythmias.
简介:ObjectivesTheeffectsofcarvediloloncalciumcurrent(ICa)wereinvestigatedinisolatedadultratventricularmyocytes.MethodsICawasrecordedbyusingwhole-cellpatch-clamprecordingtechnique.ResultsCarvedilolreversiblyinhibitedICainaconcentration-dependentmanner,carvedilolat0.1,0.3,1and10μmol/LintheextracellularsolutiondecreasedpeakICaby1.52%,18.04%,37.34%and72.18%,respectively.Thesteady-stateinactivationcurveofICawasshiftedtomorenegativepotentials,whiletheactivationcurvewasnotaltered.Therecoveryfrominactivationwasshiftedtorightdirection,itcouldnotberecoveredcompletely.Inaddition,Pretreatmentofventricularmyocyteswithprazosinandpropranololcouldn'tblockthecarvedilol-inducedreductionofICa.ConclusionsCarvedilolinhibitsICainadultratventricularmyocytesbymechanismsinvolvingpreferentialinteractionwiththeinactivatedstateofcalciumchannel.
简介:ObjectivesToevaluateantihypertensiveefficiencyandsafetyofanewdomesticofL-&N-typeCa^2+antagonist-eilnidipinewithimidaprilasapositivecontrol.MethodsAfter2weeks'placebowashingout,22patientsweretreatedwitheilnidipine5mgdailyand27patientsweretreatedwithimidapril5mgdaily.4weekslater,ifpatient'ssittingdiastolicbloodpressureisover90mmHg,his/herdosagewasdoubledforanother4weeks,theothersmeasuringupremainedtheirdosageunchangedforanother4weeks.Bloodpressure,heartrate,bloodandurineroutineexamination,serumglucose,serumchemicalexaminationincludingtotalcholesterol,triglyceride,HDL,LDL,transaminase,creatineetcandsidereactionswererecordedbeforeandafterthetrial.Datawereanalyzedstatistically.ResultsAfter8weeks'treatment,bloodpressurewassignificantlydecreased(P<0.05)inbothgroups,andthetwomedicineshadsimilarantihypertensiveeffects.Furthermore,thereducingofheartratewasstatisticallysignificantcomparedwithbaseline(P<0.01)inthecilnidipinegroup,butnotintheimidaprilgroup.Thenegativechronotropiceffectofcilnidipinehadlittleeffectoncontinuingthetherapy.Therewerenochangesonbloodandurineroutineexaminationandserumlipid,serumglucose,creatine,transaminaseandetcinbothgroups.Theirsidereactionsweremildandwell-tolerated.ConclusionsCilnidipinehasacon-vincingantihypertensiveeffectsimilartothatofimi-dapril.Especiallycilnidipinemaybeadministeredtopatientswithrelativelymildtachycardia.
简介:ObjectivesToinvestigateeffectofAngll,captoprilonsingleguineamyocytesonL-typecalciumcurrentandsodiumcurrent.MethodsMembranepatchclampwholecellrecordingtechniquewasusedtoinvestigateeffectofangll,captoprilonL-Camaximumcurrentdensityandsodiummaximumcurrentdensity.ResutlsAngllincreasedthemaximumcurrentdensitycomparedwithcontrolafterperfused5min,357.7±219.7Vs279.5±240.5PA/PF,increaserateis27.9%,theshapeofcurrent-voltagerelationshipcurvewasunchanged,peakedat+10mv,indicatedthatangllincreasedL-Cacurrentdensityinvoltage-dependent.Afterperfusedwithcaptopril,captopril+angll3,5min,L-Cacurrentwasrecorded,resultssuggestL-Camaximumcurrentdensitydecreasedsignificantlycomparedwithcontrol,incaptoprilgroup,128.4±92.6Vs286.2±89.7,66.7±68.3Vs286.2±89.7,respectively,rateofinhibitionis55.1%,76.6%,respectively.L-Cacurrentfurtherdecreasedincaptoprilpe
简介:目的观察扩张型心肌病(DCM)24h12导联动态心电图改变。方法58例均经心脏超声检查诊断为DCM,再行24h12导联动态心电图监测。结果所有病例动态心电图均有异常改变,以心律失常最为常见。其中室性心律失常56例(96.6%),房性心律失常43例(74.1%),ST—T改变32例(55.2%)、室性心动过速29例(50.0%)。心功能越差,复合性心律失常越多见。传导阻滞25例(43.1%),房室肥大27例(46.6%),Q—T间期延长24例(41.4%),异常Q波8例(13.8%)等。结论DCM有多种心电图表现,其多发、多样性心律失常对DCM早期诊断有重要意义。有复合心律失常的患者有必要进行心脏超声心动图检查。