INTERPRETATION of INTERPRETATION of ELECTROCARDIOGRAMSELECTROCARDIOGRAMS

BRIAN D. LE, MDBRIAN D. LE, MDPresbyterian HospitalPresbyterian Hospital

CIVACIVA

OutlineOutline

I.I. Approach to interpretation of ECGsApproach to interpretation of ECGs

II.II. Cases illustrating approach Cases illustrating approach principlesprinciples

III.III. Unusual CasesUnusual Cases

Seven Step ApproachSeven Step Approach

RateRate RhythmRhythm AxisAxis IntervalsIntervals HypertrophyHypertrophy ST/Tw changes, Q wavesST/Tw changes, Q waves Conduction system Conduction system

Seven Step ApproachSeven Step Approach

RateRate RhythmRhythm AxisAxis IntervalsIntervals HypertrophyHypertrophy ST/Tw changes, Q wavesST/Tw changes, Q waves Conduction system Conduction system

Seven Step ApproachSeven Step Approach

RateRate RhythmRhythm AxisAxis IntervalsIntervals HypertrophyHypertrophy ST/Tw changes, Q wavesST/Tw changes, Q waves Conduction systemConduction system

Seven Step ApproachSeven Step Approach

RateRate RhythmRhythm AxisAxis IntervalsIntervals HypertrophyHypertrophy ST/Tw changes, Q wavesST/Tw changes, Q waves Conduction systemConduction system

Seven Step ApproachSeven Step Approach

RateRate RhythmRhythm AxisAxis IntervalsIntervals HypertrophyHypertrophy ST/Tw changes, Q wavesST/Tw changes, Q waves Conduction system Conduction system

INTERVALS

PR < 200 ms

QRS < 120 ms

QTc: Men < 440 ms, Women < 460 ms

Seven Step ApproachSeven Step Approach

RateRate RhythmRhythm AxisAxis IntervalsIntervals HypertrophyHypertrophy ST/Tw changes, Q wavesST/Tw changes, Q waves Conduction system Conduction system

Left Ventricular HypertrophyLeft Ventricular Hypertrophy Cornell +R (aVL)+Sw(V3)>24mm (male) Cornell +R (aVL)+Sw(V3)>24mm (male)

>20mm >20mm (female)(female)

Sokolow S(V1) + R(V5)=32mmSokolow S(V1) + R(V5)=32mm Rw (aVL)>11mmRw (aVL)>11mm Rw (I)>14mmRw (I)>14mm

Right Ventricular HypertrophyRight Ventricular Hypertrophy 1. RAD>100*1. RAD>100* 2. IRBBB2. IRBBB 3. R>S V13. R>S V1 4. R<S V64. R<S V6 5. R in V1>=7mm5. R in V1>=7mm 6. R V1 + S V5 or V6 >=10mm6. R V1 + S V5 or V6 >=10mm 7. RAE7. RAE 8. strain pattern in rt precordial leads8. strain pattern in rt precordial leads

Seven Step ApproachSeven Step Approach

RateRate RhythmRhythm AxisAxis IntervalsIntervals HypertrophyHypertrophy ST/Tw changes, Q wavesST/Tw changes, Q waves Conduction system Conduction system

ANATOMICAL LOCALIZATION

ANTERIOR: V1-V4, SEPTAL V1-V2

LATERAL: V5-V6, I, Avl

INFERIOR: II, III, aVF

Seven Step ApproachSeven Step Approach

RateRate RhythmRhythm AxisAxis IntervalsIntervals HypertrophyHypertrophy ST/Tw changes, Q wavesST/Tw changes, Q waves Conduction systemConduction system

LBBBLBBB QRS > 0.12 secQRS > 0.12 sec wide monophasic R in I, V5 and V6wide monophasic R in I, V5 and V6 (usually notched or slurred)(usually notched or slurred) no Q in I, V5 and V6no Q in I, V5 and V6

Left Anterior Fascicular BlockLeft Anterior Fascicular Block LAD > -30', + I, aVR, -II/III/aVFLAD > -30', + I, aVR, -II/III/aVF qR in I and LqR in I and L rS in II, III and aVFrS in II, III and aVF

Left Posterior Fascicular BlockLeft Posterior Fascicular Block RAD > 100'RAD > 100' small R in I and aVL, Q in II, III, aVFsmall R in I and aVL, Q in II, III, aVF S1 Q3 patternS1 Q3 pattern

RBBBRBBB QRS>0.12 secQRS>0.12 sec R' > r in right precordiumR' > r in right precordium wide S in I, V5 and V6wide S in I, V5 and V6

Normal Variants- Juvenile Tw Normal Variants- Juvenile Tw inversionsinversions

Nuts and BoltsNuts and Bolts

Electrode MisplacementElectrode Misplacement

Amplitude ArtifactAmplitude Artifact

Parkinson’s TremorParkinson’s Tremor

CASESCASES

Case 1: Case 1: 21 yo presents for 21 yo presents for routineroutine physical examphysical exam

DEXTROCARDIADEXTROCARDIA

Case 2: Case 2: 38 yo with one week of 38 yo with one week of URIURI

presents with chest pain presents with chest pain

Acute PericarditisAcute Pericarditis

Stage I--ST elevation, Tw upright,Stage I--ST elevation, Tw upright, PR depressionPR depression Stage II--ST baseline, flattened TwStage II--ST baseline, flattened Tw Stage III--inv TwStage III--inv Tw Stage IV--Tw baseline, days to wksStage IV--Tw baseline, days to wks

Case 3: Case 3: 48 yo homeless man 48 yo homeless man foundfound

unresponsive unresponsive

HypothermiaHypothermia

Case 4: Case 4: 34 yo ESRD missed 34 yo ESRD missed three three

days of dialysis days of dialysis

HyperkalemiaHyperkalemia

Case 5: Case 5: 28 yo woman s/p neck 28 yo woman s/p neck surgerysurgery

HypocalcemiaHypocalcemia

Case 6: Case 6: 32 yo female on 32 yo female on antidepressantsantidepressants

had syncopehad syncope

Acquired Long QT SyndromeAcquired Long QT Syndrome

Case 7: Case 7: 60 yo man with chest 60 yo man with chest painpain

Inferior MI with RV infarction and Inferior MI with RV infarction and 2:1 and complete heart block2:1 and complete heart block

2:1 Heart block with 2:1 Heart block with ventriculophasic effectventriculophasic effect

Case 8Case 8: : 80 yo man with syncope80 yo man with syncope

Aflutter with complete heart Aflutter with complete heart blockblock

Aflutter with normal conduction

Aflutter with complete heart block

Aflutter with 1:1 conductionAflutter with 1:1 conduction

Aflutter with carotid sinus Aflutter with carotid sinus massagemassage

Counter-clockwise AflutterCounter-clockwise Aflutter

Clockwise AflutterClockwise Aflutter

Case 9: 50 yo man with DCMCase 9: 50 yo man with DCM

Biventricular pacingBiventricular pacing

Case 10Case 10: : 25 yo man with 25 yo man with palpitationspalpitations

Pre-excited Atrial Fibrillation- Pre-excited Atrial Fibrillation- right sided postero-septal right sided postero-septal

pathwaypathway

Wolf-Parkinson-White: Left Wolf-Parkinson-White: Left anterolateral pathwayanterolateral pathway

Postero-septal pathway Postero-septal pathway pre-ablationpre-ablation

Post-ablation with Post-ablation with repolarization abn due to repolarization abn due to

memory effectmemory effect

Case 11: 25 yo female with Case 11: 25 yo female with lightheadedness lightheadedness

AV Node Re-entrant AV Node Re-entrant TachycardiaTachycardia

(AVNRT)(AVNRT)

Case 12: 75 yo man with Case 12: 75 yo man with ischemicischemic

DCM and syncope DCM and syncope

Ventricular TachycardiaVentricular Tachycardia

BRUGADA'S CRITERIA- Circulation '91BRUGADA'S CRITERIA- Circulation '91 1. Absence of all RS complex in all 1. Absence of all RS complex in all

precordial leads S 21%, SP 100%precordial leads S 21%, SP 100% 2. R to S interval > 100ms in one 2. R to S interval > 100ms in one

precordial lead S 65%, SP 98%precordial lead S 65%, SP 98% 3 A-V Dissociation, fusion, capture 3 A-V Dissociation, fusion, capture

beats S 82%, SP 98%beats S 82%, SP 98% 4. Morphologic criteria in V1+2, 64. Morphologic criteria in V1+2, 6

Ventricular TachycardiaVentricular Tachycardia

Ventricular Tachycardia: AV Ventricular Tachycardia: AV dissociation, RS >100msdissociation, RS >100ms

Case 13: Case 13: 18 yo Asian man with 18 yo Asian man with family history of SCD presents family history of SCD presents with syncopewith syncope

Brugada SyndromeBrugada Syndrome

Genetic mutation in SCNA5Genetic mutation in SCNA5 Predominantly in Asian malesPredominantly in Asian males Syncope and sudden cardiac deathSyncope and sudden cardiac death Three typesThree types

Brugada’s Type II- Saddle Brugada’s Type II- Saddle backback

Case 14: Case 14: 28 yo man with 28 yo man with syncopesyncope

Arrythmogenic Right Arrythmogenic Right Ventricular Dysplasia (ARVD)Ventricular Dysplasia (ARVD)

Case 15: 28 yo man with Case 15: 28 yo man with syncopesyncope

Short-coupled TorsadesShort-coupled Torsades

Case 16Case 16: : 34 yo woman with 34 yo woman with fatigue, weight gain, and abn fatigue, weight gain, and abn menstrual periodmenstrual period

MyxedemaMyxedema

Case 17: Case 17: 84 yo man with skipped84 yo man with skipped beats beats

Sino-atrial exit block Type ISino-atrial exit block Type I

Case 18Case 18: : 64 yo woman presents 64 yo woman presents forfor

routine exam routine exam

Retrograde concealed Retrograde concealed conduction into the AV nodeconduction into the AV node