AvinashKhanna,MD,FACC,FSCAI

February 10, 2018

EKG Boot Camp

Objectives

•  TheBasics•  Interpreta/on•  ClinicalPearls•  Prac/ceRecogni/on

The Normal Conduction System

11 Step Method for Reading EKG’s

“DataGathering”–steps1-4

• 1.Standardiza/on–makesurepaperandpaperspeedisstandardized• 2.HeartRate• 3.Intervals–PR,QT,QRSwidth• 4.Axis–normalvs.devia/on

11 Step Method for Reading EKG’s

“Diagnoses”

– 5.Rhythm– 6.Atrioventricular(AV)BlockDisturbances– 7.BundleBranchBlockorHemiblock

– 8.Preexcita/onConduc/on– 9.EnlargementandHypertrophy– 10.CoronaryArteryDisease– 11.UWerConfusion

Lead Placement

Rate

•  Ruleof300-Divide300bythenumberofboxesbetweeneachQRS=rate

Number of big boxes

Rate

1 300

2 150

3 100

4 75

5 60

6 50

What is the heart rate?

(300 / 6) = 50 bpm

www.uptodate.com

Normal Intervals

•  PR-0.20sec(lessthanonelargebox)

•  QRS-0.08–0.10sec(1-2smallboxes)

•  QT-450msinmen,460msinwomen-Basedonsex/heartrate-HalftheR-RintervalwithnormalHR

Prolonged QT

•  Normal-Men450ms-Women460ms

•  CorrectedQT(QTc)-QTm/√(R-R)

•  Causes-Drugs(Nachannelblockers)-Hypocalcemia,hypomagnesemia,hypokalemia-Hypothermia-AMI-Congenital-IncreasedICP

The QRS Axis

•  Represents the overall direction of the heart’s activity

•  Axis of –30 to +90 degrees is normal

The Quadrant Approach

•  QRSupinIandupinaVF=Normal

What is the axis? •  Normal-QRSupinIandaVF

Rhythm

•  Sinus-  Origina/ngfromSAnode

-  PwavebeforeeveryQRS

-  Pwaveinsamedirec/onasQRS

What is this rhythm? Normalsinusrhythm:

Supraventricular Arrhythmias

•  PSVT-regular;Pwavesretrogradeifvisible;rate150-250bpm;caro/dmassage:slowsorterminates

•  FluWer–regular;saw-toothedpaWern;2:1,3:1,4:1,etc.block;atrialrate250-350bpm;ventricularrate½,⅓,¼,etc.ofatrialrate;caro/dmassage:increasesblock

•  Fibrilla/on–irregular;undula/ngbaseline;atrialrate350to500bpm;variableventricularrate;caro/dmassage:mayslowventricularrate

•  Mul/focalatrialtachycardia(MAT)–irregular;atleast3differentPwavemorphologies;rate–usually100to200bpm;some/mes

•  <100bpm;caro/dmassage:noeffect

•  PAT–regular;100to200bpm;characteris/cwarm-upperiodintheautoma/cform;caro/dmassage:noeffect,ormildslowing

Supraventricular Arrhythmias

Ventricular Arrhythmias

Torsades de Pointes

Blocks AVblocks

– Firstdegreeblock-  PRintervalfixedand>0.2sec

– Seconddegreeblock,Mobitztype1-  PRgraduallylengthened,thendropQRS

– Seconddegreeblock,Mobitztype2-  PRfixed,butdropQRSrandomly

– Type3block-  PRandQRSdissociated

What is this rhythm? FirstdegreeAVblock

PRisfixedandlongerthan0.2sec

What is this rhythm?

Type1seconddegreeblock(Wenckebach)

What is this rhythm? AV block

Dropped QRS

Type 2 second degree

What is this rhythm?

3rddegreeheartblock(complete)

Bundle Branch Blocks

RBBBcriteria:1.QRScomplex>0.12seconds2.RSR’inleadsV1andV2(rabbitears)withSTsegmentdepressionandTwaveinversion3.ReciprocalchangesinleadsV5,V6,I,andaVL

LBBBcriteria:1.QRScomplex>0.12seconds

2.BroadornotchedRwavewithprolongedupstrokeinleadsV5,V6,I,andaVLwithSTsegmentdepressionandTwaveinversion.

3.ReciprocalchangesinleadsV1andV2.

4.Lemaxisdevia/onmaybepresent.

Hemiblocks Diagnosedbylookingatrightorlemaxisdevia/on:

• Le#AnteriorHemiblock•  1.NormalQRSdura/onandnoSTsegmentorTwavechanges

•  2.Lemaxisdevia/ongreaterthan-30°•  3.Noothercauseoflemaxisdevia/onispresent

• Le#PosteriorHemiblock•  1.NormalQRSdura/onandnoSTsegmentorTwavechanges•  2.Rightaxisdevia/on

•  3.Noothercauseofrightaxisdevia/onispresent

Bifascicular Block

•  RBBBwithLAH-  RBBB–QRS>0.12secandRSR’inV1andV2withLAH–lemaxisdevia/on

•  RBBBwithLPH-  RBBB–RS>0.12secandRSR’inV1andV2withLPH–rightaxisdevia/on

Preexcitation

•  Wolff-Parkinson-White(WPW)Syndrome-  1.PRinterval<0.12sec

-  2.WideQRScomplexes-  3.Deltawavesseeninsomeleads

•  Lown-Ganong-Levine(LGL)Syndrome-  1.PRinterval<0.12sec-  2.NormalQRSwidth

-  3.Nodeltawave

Preexcitation

WPW LGL

Atrial Enlargement LookatPwavesinleadsIIandV1

• Rightatrialenlargement(Ppulmonale)•  1.Increasedamplitudein

firstpor/onofPwave•  2.Nochangeindura/onofPwave

• Lematrialenlargement(pmitrale)

•  1.Occasionally,increasedamplitudeofterminalpartofPwave

•  2.Moreconsistently,increasedPwavedura/on

Ventricular Hypertrophy

LookattheQRScomplexesinallleads

• Rightventricularhypertrophy(RVH)-  1.RAD>100°-  2.Ra/oofRwaveamplitudetoSwaveamplitude>1inV1and<1inV6

• Lemventricularhypertrophy(LVH)PrecordialCriteria LimbLeadCriteriaRwaveinV5orV6+SwaveinV1orV2>35mm

RwaveinaVL>13mm

RwaveinV5>26mm RwaveinaVF>21mm

RwaveinV6>18mm RwaveinI>14mm

RwaveinV6>RwaveinV5 RwaveinI+SwaveinIII>25mm

Myocardial Infarction

•  Dx–Hx,PE,serialcardiacenzymes,serialEKG’s

•  3EKGstagesofacuteMI•  1.Twavepeaksandtheninverts•  2.STsegmentelevates•  3.Qwavesappear

Q Waves

•  CriteriaforsignificantQwaves-  Qwave>0.04secondsindura/on-  Qwavedepth>⅓heightofRwaveinsameQRScomplex

-  QwavesarenormalinleadIIIandaVRduetheirrightwardorienta/on.

Localizing MI on EKG •  InferiorinfarcKon–leadsII,III,aVF

-Omencausedbyocclusionofrightcoronaryarteryoritsdescendingbranch-Reciprocalchangesinanteriorandlemlateralleads

•  LateralinfarcKon–leadsI,aVL,V5,V6-Omencausedbyocclusionoflemcircumflexartery-Reciprocalchangesininferiorleads

•  AnteriorinfarcKon–anyoftheprecordialleads(V1-V6)-Omencausedbyocclusionoflemanteriordescendingartery-Reciprocalchangesininferiorleads

•  PosteriorinfarcKon–reciprocalchangesinleadV1(STsegmentdepression,tallRwave)-Omencausedbyocclusionofrightcoronaryartery

Localizing MI on EKG

ST segment

•  ElevaKon-  Seenwithevolvinginfarc/on,Prinzmetal’sangina-  Othercauses–Jpointeleva/on,apicalballooningsyndrome,acutepericardi/s,acutemyocardi/s,hyperkalemia,pulmonaryembolism,Brugadasyndrome,hypothermia

•  Depression-  Seenwithtypicalexer/onalangina,non-QwaveMI-  Indicatorof+stresstest

Electrolyte Abnormalities on EKG

•  Hyperkalemia–peakedTwaves,prolongedPR,flaWenedPwaves,widenedQRS,mergingQRSwithTwavesintosinewave,AVblock,VF

•  Hypokalemia–STdepression,flaWenedTwaves,Uwaves

•  Hypocalcemia–prolongedQTinterval

•  Hypercalcemia–shortenedQTinterval

Drugs

•  Digitalis-  Therapeu/clevels–STsegmentandTwavechangesinleadswithtallRwaves

-  Toxiclevels–tachyarrhythmiasandconduc/onblocks;PATwithblockismostcharacteris/c.

•  Mul/pledrugsassociatedwithprolongedQTinterval,Uwaves-  Sotalol,quinidine,procainamide,disopyramide,amiodarone,dofe/lide,dronedarone,TCA’s,erythromycin,quinolones,phenothiazines,variousan/fungals,somean/histamines,citalopram(onlyprolongedQTinterval–dose-dependent)

Digitalis

Dubin, 4th ed. 1989

EKG ∆’s in other Cardiac Conditions

•  PericardiKs:DiffuseSTsegmenteleva/onsandTwaveinversions;largeeffusionmaycauselowvoltageandelectricalalternans(alteringQRSamplitudeoraxisandwanderingbaseline)

•  MyocardiKs:conduc/onblocks

•  HypertrophicCardiomyopathy:ventricularhypertrophy,lemaxisdevia/on,septalQwaves

EKG ∆’s in Pulmonary Disorders

•  COPD:lowvoltage,rightaxisdevia/on,andpoorRwaveprogression.

•  Chroniccorpulmonale:Ppulmonalewithrightventricularhypertrophyandrepolariza/onabnormali/es

•  Acutepulmonaryembolism:rightventricularhypertrophywithstrain,RBBB,andS1Q3T3(withTwaveinversion).Sinustachycardiaandatrialfibrilla/onarecommon.

EKG ∆’s in Other Conditions

•  Hypothermia:Osbornwaves,prolongedintervals,sinusbradycardia,slowatrialfibrilla/on,bewareofmuscletremorar/fact

•  CNSDisease:diffuseTwaveinversionwithTwaveswideanddeep,Uwaves

Utter Confusion

•  Verifyleadplacement

•  RepeatEKG•  RepeatstandardizedprocessofEKGanalysis-star/ngover

fromthebeginningwithbasics–rate,intervals,axis,rhythm,etc.andproceedthroughen/restepwiseanalysis

Case

•  45yomalepresentswithacuteSOBs/plongvaca/oninParis

•  PMHx-asthma,Crohn’sdisease,anxiety,GERD,tobaccoabuse

•  VS37,148/92,130,26•  Pa/entappearsuncomfortablebutotherwise

unremarkableexam

Case

AcutePEwithsinustachycardia,aPVC,andS1Q3T3paWern

Case

•  27yofemalepresentstotheEDwithc/ochestdiscomfortandpalpita/onsamerstudyingallnightforgraduateschoolexams

•  Appearsnervousand“uneasy”withrapidpulse•  PMHx–unremarkable;nomeds,admitstooccasionalalcohol,non-smoker,deniesillicitdruguse,usedcoffeetostayawaketostudy

Case

SVT:regular,narrow-QRStachycardia,rateof160bpm

Case

•  46yomalepresentstoEDwithc/osevereHApersis/ngover5hoursdespiteacetaminophenandNSAIDaWemptsasabor/vetherapy

•  PMHx:occasionallemshoulderpain,non-smoker

•  Construc/onworker•  VSS;unremarkableexam

Normal ECG

Case

•  28yomalepresentsforcommercialdriver’slicense(CDL)evalua/on

•  Nocomplaints

•  VSS;asymptoma/c;examwithoutsignificantfindings

Case

•  Diagnosis?EKGfindings?

Case

•  Typicalpreexcita/on(WPW)paWern

•  ShortPRintervalanddeltawavesinmanyleads•  Txiscloseobserva/onunlesspa/enthashadSVToratrialfibrilla/onwhichindicatestxwithabla/onofaccessorypathway

Case

•  32yomalepresentstoEDwithc/ofeelingsickforthelast6days

•  Symptomsincludefevers,cough,anddifficultycatchinghisbreath

•  PMHx:hyperlipidemia,obesity,metabolicsyndrome

•  VS38.1,105,128/84,22

AcutepericardiKs:diffuseSTeleva/onwithPRsegmentdepressionisdiagnos/cDiagnosis?EKGfindings?

Case

•  67yomalepresentstohiscardiologistforout-pa/ent6weekpost-hospitalvisit

•  Previoushospitaliza/onfornon-cardiacchestpain

•  Post-hospitalcardiacmeds:ACEinhibitor,betablocker,aspirin,nitrate

•  Nocurrentcomplaints

Case

•  Atrialfibrilla/on:irregularlyirregularwithoutPwaves

•  RBBB:wideQRSwithrsR’paWerninV1,broadSwavesinleadsIandaVL

•  Inferiorinfarct:non-acute(>1week)pathologicQwavesininferiorleads(II,III,andaVF)

Case

•  79yomalebroughttoEDviaEMSwithchestpain,SOB,andnear-syncope

•  PMHx:unobtainablesecondarytopa/entdistress

•  VS:36.9,140’s,82/40,28

Case

Monomorphicsustainedventriculartachycardia(VT)–couldrapidlydeteriorateintoVF,torsadesdepointes,asystole,orsuddendeath.

What is the diagnosis?

AcuteinferiorMIwithSTeleva/oninleadsII,III,aVF

Junctional Rhythm

Rate 40-60, no p waves, narrow complex QRS

Hyperkalemia

Tall, narrow and symmetric T waves

Wellen’s Sign

ST elevation and biphasic T wave in V2 and V3 Sign of large proximal LAD lesion

Brugada Syndrome

RBBB or incomplete RBBB in V1-V3 with convex ST elevation

Male39Years

Brugada Syndrome

•  Autosomaldominantgene/cmuta/onofsodiumchannels

•  Causessyncope,v-fib,selftermina/ngVT,andsuddencardiacdeath

•  CanbeintermiWentonEKG•  Mostcommoninmiddle-agedmales•  CanbeinducedinEPlab•  NeedICD

Second Degree Heart Block, Mobitz Type II

PR interval fixed, QRS dropped intermittently

Hypokalemia

U waves: Can also see PVCs, ST depression, small T waves

Bonus Case

•  18yomaleundergoingmilitaryphysicalexamandevalua/onpriortobootcamp

•  Nocomplaints

•  PMHx–denies•  VSS;examunremarkable

Bonus Case

•  Diagnosis?EKGfindings?

Bonus Case

•  Reversedarmleads–invertedPwavesinleadIwithnormalRwaveprogressioninprecordialleads