心电图教学课件英文版.pptVIP

Undernormalconditions,theSTsegmentisisoelectric(Figure15)orshowsonlyasmalldescentslope(0.5mm)withascendentinclination,orasmallascentslopethatisconvexinrelationtotheisoelectriclineandusuallymorevisibleinV1–V2*QTintervalrepresentsthesumofdepolarisation(QRScomplex)andrepolarisation(STsegmentandTwave).*目测法*Ⅰ、Ⅱ、V4～V6导联向上，aVR向下，Ⅲ、aVF、V1～V3导联可以向上、双向或向下，但若V1的T波向上，则V2～V6导联就不应再向下。*chloride*Thermosensitive*amplitude*Leftatrialenlargement(LAE)isseeninpatientswithmitralandaorticvalvulardisease,ischaemicheartdisease,hypertensionandsomecardiomyopathiesbimodal*Rightatrialenlargement(RAE)isespeciallypresentinpatientswithcongenitalandvalvularheartdiseasesaffectingtherightsideoftheheart*Leftventricularenlargement(LVE)isfoundparticularlyinhypertension,ischaemicheartdisease,valvularheartdisease,cardiomyopathiesandsomecongenitalheartdiseases.*R波为主*Rightventricularenlargement(RVE)isfoundparticularlyinthecasesofcongenitalheartdiseases,valvularheartdiseasesandcorpulmonale.*相互抵消*Sinustachycardiaisanormalresponsetophysicalexercise,emotionalexcitement(suchasfright),severeanaemia,hyperthyroidism，sepsis,fever,catecholaminesurgeandadrenergicmedications(suchasbetaagonistsgivenasbronchodilators).*Ectopic颅高压jiajia甲减*心电图特征1.明显而持久的窦性心动过缓（心率＜50次／min，且不易用阿托品等药物纠正）；2.多发的窦性静止或严重的窦房阻滞。3.明显的窦性心动过速而常出现室上性快速心律失常发作，故亦称心动过缓－过速综合征。4.若同时累及房室交界区，可发生房室传导阻滞或窦性停搏后长时间无交界性逸搏,成为双节病变*交界性心律其激动发源于房室结区或结－希区，其下传心室时与窦性激动的下传途径相同或相似，所以QRS结与窦性者相同或相似。交界区的激动也能同时逆行上传达心房，产生一个逆行P’波（Ⅱ、Ⅲ、aVF的P’倒置，aVR的P’直立），P’波可出现于QRS波之中、之后，也可在其前，但P’－R0.12sec，R－P’0.20sec，*vary*多系异位节律点兴奋性增高、触发活动或形成折返激动所引起，是最常见的心律失常。早搏可以来自各种不同的异位节律点，最多见的是室性早搏，交界性早搏较少见。Extrasystolebyanintracellularbuild-upofpositiveions,(usuallycalcium)thatcantriggeranimpulsecausingdepolarisationthatdoesnotoriginatefromtheSAN.Theotherprincipleme