Simon Simon AbouAbou JaoudJaoudééCardiology DepartmentCardiology Department

HôtelHôtel--DieuDieu

ECG reading: the common and dangerous

ECG reading: the ECG reading: the common and dangerouscommon and dangerous

Review essential technical aspects of ECG recordingReview essential technical aspects of ECG recording

Content and ObjectivesContent and Objectives

Distinguish between Distinguish between ““normalnormal”” and and ““abnormalabnormal”” ECG findingsECG findings

List the criteria for heart blocks and WPWList the criteria for heart blocks and WPW

Recognize arrhythmia type during sustained tachycardiaRecognize arrhythmia type during sustained tachycardia

Identify main ECG abnormalities caused by MI and ischemiaIdentify main ECG abnormalities caused by MI and ischemia

common technical pitfallscommon technical pitfalls

Lead placementLead placement

FFIILLTTEERR

OONN

Paper SpeedPaper Speed

50 mm/sec 25 mm/sec

0,04 sec 0,2 sec

TEMPS

VO

LT

AG

E

25mm/sec

10 m

m/m

V 0,04 sec

motion motion artifactartifact

--breathingbreathing

stop breathingstop breathing

Auto modeAuto mode

Lead InversionLead Inversion

L R

Normal ECG ??Normal ECG ??

•• 62 y 62 y •• emergency departmentemergency department•• chest painchest pain

•• 62 y 62 y •• emergency departmentemergency department•• chest painchest pain

T wave polarity depends on T wave polarity depends on

T wave axisT wave axis

I

II

III

Frontal PlaneFrontal Plane

T wave is always positive in leads I and IIT wave is always positive in leads I and II

may be negative in lead III.may be negative in lead III.

T wave is always positive in T wave is always positive in precordialprecordialleads.leads.

(except V1: may be negative)(except V1: may be negative)

• 75 y W• elective cholecystectomy• pre op ECG

Normal ECG ??Normal ECG ??

I

ExpirationExpiration InspirationInspiration

Positional Q waves (Positional Q waves (septalseptal Q waves)Q waves) often disappears with often disappears with change in heart orientation associated with deep inspiration change in heart orientation associated with deep inspiration

• 33 y M• ER• chest pain x 3 hours

Normal ECG ??Normal ECG ??

““Early Repolarisation SyndromeEarly Repolarisation Syndrome”” ““High takeHigh take--off ST segmentoff ST segment””

TachycardiaTachycardia

Atrial Fibrillation

TachycardiaTachycardia (HR > 100/min)(HR > 100/min)

RegularRegularIrregularIrregular

Atrial Fibrillation

SVTSVT

TachycardiaTachycardia (HR > 100/min)(HR > 100/min)

RegularRegularIrregularIrregular

Atrial Fibrillation

NarrowNarrow QRS tachycardiaQRS tachycardia(< 0.12 sec)(< 0.12 sec)

WideWide QRS tachycardiaQRS tachycardia(> 0.12 sec)(> 0.12 sec)

““ SVTsSVTs ””

Sinus Tachycardia

Atrial Tachycardia

Atrial Flutter

AVNRT-AVRT(Bouveret)

VTVT

““ SVTsSVTs ””

+ WPW

+ BBB

VTVT

P wave ?

Identifying P wave: several approaches

- Spontaneous on surface ECG(compare with previous tracings)

- Lewis lead (DI on chest)- Esophageal lead- Epicardiac lead (post open heart)- CSM, ATP, AdenosineAdenosine

Analyze P wave- Morphology- Timing- Rate

““ SVTsSVTs ”” (Regular, Narrow QRS tachycardia)

Analyze P wave- Morphology- Timing- Rate

“sinus” morphology: positive P wave in leads I and Vf

P P wavewave

II

aVfaVf

Analyze P wave- Morphology- Timing- Rate

“P” wave rate

120-150 250 350 /min

Sinus Atrial Atrial Atrialtachy tachy flutter fibrillation

sinus tachycardia

Regular narrow QRS tachycardia at 150/minRegular narrow QRS tachycardia at 150/min AdenosineAdenosine

Regular P waves at 150/minRegular P waves at 150/minAdenosineAdenosine

1/1 Atrial Tachycardia

ATPATP Regular P waves at 300/minRegular P waves at 300/min

Regular tachycardia at 150 / minRegular tachycardia at 150 / min 2/1 Atrial Flutter

AVNRT

AdenosineAdenosine

Adenosine

2003 ACC/AHA/ESC Guidelines for Management of SVA

ECG in CADECG in CAD

definedefine

-- typetype of ischemic changesof ischemic changes-- localizationlocalization of ischemic changesof ischemic changes

ECG in CADECG in CAD

Q waveQ wave

ST changesST changes

T wave T wave changeschanges

depolarization depolarization abnormalitiesabnormalitiesirreversibleirreversibleInfarction:Infarction:

1/ elevated ST1/ elevated ST

2/ depressed ST2/ depressed STrepolarisation repolarisation abnormalitiesabnormalitiesreversiblereversibleInjury :Injury :

1/ inverted T wave1/ inverted T wave

2/ Peaked T wave2/ Peaked T waverepolarisation repolarisation abnormalitiesabnormalitiesreversiblereversibleIschemia :Ischemia :

-- typetype of ischemic changesof ischemic changes

ECG in CADECG in CAD

Inverted T waveInverted T wave

Peaked T wavePeaked T wave

Elevated STElevated ST

Depressed STDepressed ST

IschemiaIschemia

InjuryInjury

antero-apical postero-inferior

antero-lateral

anterior

antero-septal

RV

postero-basal

Lateral Lateral viewview

Localization of ischemic changesLocalization of ischemic changes

anterioranteriorviewview

V1V1V2V2 V3V3

V4V4

V5V5

V6V6

VL VL leadlead I I

II III VFII III VF

V4rV4rV3rV3r

++

++antero-septal : V1 V2

apical : V3 V4

lateral : V5 V6

high lateral : I -VL

anterior : V1 - V6

postero-inferior : II -III -VF

postero-basal : V7 V8 V9

RV : V3r V4r

Localization of ischemic changesLocalization of ischemic changes

Heart blocks and WPWHeart blocks and WPW

AV node

His

-- Sinus dysfunctionSinus dysfunction

-- AV BlockAV Block

Heart blocksHeart blocks

PR > 0,2 secPR > 0,2 sec

1st degree AV block

«« progressiveprogressive »» AV blockAV block

Mobitz 1 AV block

constant PRconstant PRblocked P waveblocked P wave

Mobitz 2 AV block

P waveP wave

QRSQRS

Complete AV block

AV dissociationAV dissociation

sinus arrestsinus arrest

junctionaljunctional escape rhythmescape rhythm

Sinus dysfunction

KENTKENT

Wolf Parkinson White Syndrome Wolf Parkinson White Syndrome

Zone ventriculaire préexcitée

Zone excitée normalement

Wolf Parkinson White Syndrome Wolf Parkinson White Syndrome