心电图介绍-李宁

《心电图介绍-李宁》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、李宁心电图QuestionsWhyECGcouldbeservedforthediagnosisofsomediseases?WhatisECG?WhatisnormalECG?正常心电图A.BasicknowledgeofECGDepolarizationandrepolarizationSinglemyocardialcellAmusclestrip心电生理心脏传导系统接受迷走-交感神经支配ThenormalSinusNodeRhythm3.PacingandconductingsystemoftheheartSinusnodeInternodaltracts

2、AVnoderightbundlebranch(RBB)PurkinjefibersBundleofHisanteriorfascicleleftbundlebranch(LBB)Purkinjefibersposteriorfascicle心率估算法一个RR间期的大格数心率1300215031004755606507.540…………电轴临床工作中很少测量P波和T波的电轴，而QRS波群的电轴变化常与心脏病变密切相关。电轴的正常值在-30~+90度，-30~-90度电轴左偏，+90~+180电轴右偏，-90~+180度电轴不确定P波形态：在Ⅰ、Ⅱ、aVF、V4-V6导

3、联中均向上，aVR导联向下时间：正常人小于0.12s振幅：在肢体导联小于0.25mv,胸导联小于0.2mvP-R间期成年人的P-R间期为0.12-0.20S。在老年人及心动过缓的情况下，P-R间期可略延长但不超过0.22S。ST段在任一导联ST段下移不超过0.05mv，ST段上抬在V1-V2导联不超过0.3mv,V3不超过0.5mvV4-V6与肢体导联不超过0.1mv。T波（1）方向：大多和QRS主波的方向一致。若V1的T波向上，则V2-V6导联就不应再向下。（2）振幅：除Ⅲ、aVL、aVF、V1-V3导联外，T波的振幅一般不应低于同导联R波的1/10。T波在胸导联有

4、时可高达1.2-1.5mv尚属正常。Q-T间期正常范围为0.32-0.44S。Q-Tc就是R-R间期为1s(心率60次/分）时的Q-T间期。Q-Tc的正常上限为0.44S。U波U波方向大体与T波相一致。U波明显增高见于血钾过低。PartIIIAtrialEnlargementandVentricularHypertrophy(1)LeftAtrialEnlargementLeadIIDurationofPwave≥0.12sec.;Pwavebecomebifid(P"mitrale");Thedistanceoftwopeak≥0.04sec.LeadV1Pwa

5、vebecomebiphasic;Ptfv1-0.04mm·secRightAtrialEnlargementLeadIIPwaveispeaked(P"pulmonale");AmplitudeofPwave≥0.25mVinlimbleads.BiatrialEnlargementLeadIIPwavedurationandamplitudebothincreased.LeftVentricularHypertrophyA.IncreasedvoltageSV1+RV5>3.5mV(female),4.0mV(male);Rv5orRv6>2.5mV;RI>1

6、.5mV;RaVL>1.2mV;RaVF>2.0mV;RI+SIII>2.5mV;B.LeftaxisdeviationC.STdepressionandTinversioninV5-6.RightVentricularHypertrophyA.Increasedvoltage(adultsover30)R/SratioinV1>1.0;R/SratioinV5orV6≤1.0;R/qorR/SratioinaVR≥1;RV1+SV5>1.05mV(severe>1.2mV);RaVR>0.5mV;B.Rightaxisdeviation≥+900(severe

7、>+1100).C.STdepressionandTinversionV1-2.PartVIMyocardialIschemiaandMyocardialinfarctionECGofmyocardialischemiashows:STsegmentdepression;STsegmentelevation(coronaryspasm);Inverted,diphasic,lowTwave.Myocardialinfarction(1)Basicchanges“Hyperacute”TWaves.TallpeakedTwaves,oftenappe