Kittikarn Thongsonkreeb

Electrical cells: Pacemaker cell Fiber tract

Mechanical cells : Myocardium

Sinoatrial node (SA node): Primary pacemaker (rate 60-100/min)Atrioventricular junction: Escape pacemaker (AV node, bundle of His rate 40-60/min)Purkinje system: Escape pacemaker (rate < 40/min)

saline , gel

Isoelectric line : Upright/positive : Inverted/negative :

12 leadsBipolar limb leads 3 leads : I ,II, IIIUnipolar limb lead 3 leads : aVR,aVL,aVFPrecordial chest leads 6 leads : V1-V6!!! LeadIII aVRII aVLI aVF

Right armLeft armRight leg (ground electrode)Left leg

V1 : right 4th ICS sternumV2 : left 4th ICS sternumV3 : V2 V4V4 : left 5th ICS , Midclavicular lineV5 : left 5th ICS , Anterior axillary lineV6 : left 5th ICS , Middle axillary line

stylus 25 mm/secVoltage 10 mm (2 ) = 1 mV 1 = 0.20 1 = 0.04

P wave : atrial depolarizationPR interval : P wave QRS complex (atrial depolarization ventricle depolarization)PR segment : AV nodeQRS complex : ventricular depolarizationT wave : ventricular repolarizationU wave : repolarization of Purkinje system

ComponentsNormal limit (!!!)P waveAtrial depolarization x = 2 x 2.5 RA, LA , ectopyPR delay AV/BB/muscle etc.3-5 Heart block Q x = 1x2 , else patho QOLD MIQRSVentricular depolarization 5 2.5 -: LVH, RVH, : Ventricular rhythm, BBB, HyperKSTPhase 2 ventricular depoisoelectricNSTEMI, STEMI, Pericarditis, LVH strain, Dig intoxTPhase 3 Ventricular repolarization< 2/3 R R-: Hyper/hypoKInvert: ischemia, infarctQT ventricle8-11 Hyper/hypoCal, Dig intox, antiarrhythmicURepolarization of Purkinje system normal post exerciseHyperCal, HyperThyroid, HypoK

Rate: 300/, 1500/, regular Rhythm:sinus? OR non-sinus (atrial?, Junctional (AV)?, Ventricular?)AxisP: 2 x 2.5 RA, LA PR: >5 AV blockQRS: RVH, LVH, BBBST:depress, elevate MI, pericarditisT: peak T, invert T MI, hyper KU: HyperCal, HyperThyroid, HypoK

: 300/, 1500/: 300 150 100 75 60 50 45 40 35 30

Sinus tachycardia: rate > 100Sinus bradycardia: rate < 60Normal sinus rhythmP II, III, aVF, aVRSame p contour in the same leadOne p for every QRSPR < 5 Regular rate 60-100Normal R progression

Regular rhythm with rate < 60 beat/min (45-59)Uniform P wavePR interval NOT PROLONGED MI , sick sinus syndromeHypothyroidismBeta blocker ******

Rate > 100 beat/min (101-160)1 P 1 QRS , MyocarditisPulmonary embolism********* + (SI, QIII, TIII)Increase cardiac output : fever, hyperthyroidism, anemia

Respiratory sinus arrhythmia SA node Nonrespiratory sinus arrhythmia SA node

SA node atrial depolarization AMISick sinus syndrome

Reentry focus in atria 250 Atrial rate 250-350 beat/minP wave : sawtooth pattern

Identify P wave QRS Irregularly Irregular

Aging: 10% > 70 15% > 90IschemiaAlcohol abuseHyperthyroidism

Treatment Heart rate control (

Regularity : regularRate : 130-210P wave : QRS complex P wave P wave lead II ( AV)QRS : 3

QRS : 3 rhythm (Ventricular ectopy) rhythm EKG ( complete heart block, Ventricular tachycardia)

Ventricular irritability ventricular contraction

I, II, III Biphasic axis Lead biphasic ( I Bi aVF -ve axis = -90) Biphasic Lead Lead 15

Example I +ve II ve III ve aVR ve aVL +ve aVF -ve

!! limb lead Axis = 75 - 30x -15y Lead I = 105 + 30x +15y Lead I

X = Lead Y = Lead biphasic( lead I)

LeadAxisII+III+aVR-aVL-aVF+

Axis = -15

Axis = -165

Axis = +30

lead II Normal: 2x2.5 RA/LA enlargementRA : peak P 2.5 DDx: Cor pulmonale, congenital PS or tricuspid atresia, TR, TSLA : wide & notch biphasic P V1

DDx: MS ( 3 ), MR ( 4 ), LA myxoma

Criteria:p wave 3 negative p V1 1 Left atrial abnormality:1 of 2 CriteriaLeft atrial enlargement:2 of 2 Criteria

5 = Prolonged AV block 1st degree: PR prolong 5 2nd degree: - Mobitz I: PR prolong QRS 1 prolong - Mobitz II: PR QRS - 2:1 AV block: P-P-QRS (High grade)3rd degree: P QRS rate QRS Junctional () ventricular rhythm ()

PR = 6

Mobitz I: PR prolong QRS 1 prolong

Mobitz II: PR prolong QRS

2:1 AV block: P-P-QRS

P QRS rate QRS Junctional () ventricular rhythm ()

LVH, RVH, BBBNormal: 5 2.5 Normal R progression: R V1 V4-5S V1 V6Biphasic V3-4

V1: R S V3-4: BiphasicV5-6: Q S

Tall R in V1 DDx ???Rt. Block: RBBBClockwise: Clockwise rotation: Dextrocardia, Situs inversus: Posterior wall MI RV: RVH : WPWHypertrophic obstructive cardiomyopathyDuchenne muscular dystrophyMisplaced electrode

EKG sensitivity Gold standard = EchocardiogramVoltage criteriaNormalPressure loadVolume load AS, Coarc, HTN AR, MR, PDA, etc.

Criteria for RVH ( LV DDx LVH)1. R V1 (7 ) + S V6 (10.5 )2. Strain (ST depress V1-2) pressure load3. +/- Rt. axis deviationDDx:1. LA : MS, Myxoma 2. LA : COPD, Cor, PE, PAHT, PS

Criteria for LVH1. [max S in V1-2] + [max R in V5-6] >352. Strain (ST depress V4-6) pressure load3. +/- Lt. axis deviationDDx:1. Pressure load: AS, Coarc, HTN 2. Volume load: AR, MR, PDA

Incomplete vs Complete block Incomplete: QRS < 3 Complete: QRS > 3 M-pattern:rSR pattern: M rSR Lead Block

Can be normal variantM rSR () V1-3 + Slur S V6

Always ABNORMAL!!!M V5-6 + Slur S V1 DDX: Cardiomyopathy, Ischemia, Myocarditis, LVH, HTN

Complete block (QRS > 3 ) !!! M rSR LBBB, RBBB

Pathologic Q wave: > 1 > 2 lead 2 leads ST elevation: ST segment > 2 mm V1-2 > 1mm Lead 2 leads ST depression: > 0.5 mm Lead J point HorizontalDownsloping

More remnant R wave: better prognosis (Still have some good wall left)Persistent ST elevation: Possibly ventricular aneurysm

LCXRCA supply SA node 60% AV node 80% Right ventricle Posterior wall 75% Inferior wallLCX supply Posterior wall 25% Inferior wall lateral wall of LV SA node 40% AV node 10%LAD supply Septal wall of LV Anterior wall of LV Lateral wall of LV LBB, RBB

ST depression Lead lead ST elevation NSTEMI Lead

Inferior wall MI I, aVLAnterior wall MI II, III, aVF

Anterior wall MI Reciprocal proximal LAD stenosis Poor prognosis

ST Elevate inII, III, aVF:RCAOR LCX+ V1, V3R, V4R:proximal RCA+ V5, V6, I, aVL:LCX+ ST depress V2-4:inferoposterior MI+ dominant R in V1-2:inferoposterior MIV1-V4 (at least 2):LADV2-4:mid LADV1-6, I, aVL:proximal LAD (extensive wall MI)V5, V6, I, aVL:LCX: EKG single vessel

ST elevate in II, III, aVF 2 RCA, LCX RCA stenosis: RV infarct (V3R,4R) III Elevate IILCX stenosis: lateral infarct (V5-6, I, aVL) II Elevate III Inferior wall infarct ST depress V2-4 dominant R V1-2 Posterior wall infarct V7-9 Inferior wall V3R,4R V7-9

Acute inferoposterolateral STEMI, possibly LCX occlusion

Acute anteroseptal STEMI, possibly proximal LAD occlusion

Acute inferoposterior wall STEMI, possibly RCA occlusion

Acute extensive wall STEMI, possibly proximal LAD occlusion

Acute inferior wall STEMI, vessel??

Acute inferior wall STEMI c RV infarct, RCA occlusionV3RV4RV5RV6R

A 25 YOM presenting with sudden cardiac arrest, the EKG at ER shows

After CPR 5 min & Defibrillation, patient was recovered. The 12-lead EKG was obtained

Brugada syndrome: Mutation of Na channel

Reentry: 2 different conduction fibersMost common cause of tachyarrhythmiaAVNRT, Aflut, VTEctopy: abnormal automaticity of ectopic fociCause from abnormal tissue, e.g. post cardiac surgery, post MIAtrial tachycardia

NarrowWideRegular Sinus tachycardia Atrial flutter Atrial tachycardia PSVT (AVNRT, AVRT) VT SVT c BBB Antidromic AVRTIrregular P: AT/Aflut c varying block MAT P: AF AF c BBB/WPW Aflut/AT c varying block c BBB/WPW

Most common isSinus tachycardia

Rate > 100 beat/min (101-200)1 P 1 QRS , Increase cardiac output : fever, hyperthyroidism, anemiahypoxemiaHypovolemiaMyocarditisPulmonary embolism********* + (SI, QIII, TIII)

Macro reentry focus in atria 250 Atrial rate 250-350 beat/minP wave : sawtooth pattern 2:1 block (rate = 150)

AV node blocker slow rate flutter wave

Ectopic foci in atrium: rate SA node (150-250) ASD (Scar formation) Isoelectric p wave p wave lead II, III, aVF SVT P QRS

AV nodal reciprocating tachycardia (AVNRT) reentry circuit AV nodeAV reciprocating tachycardia(AVRT)Reentry circuit accessory pathway

Reentry circuit in AV node, Precedes with PAC 70% no retrograde PPseudo S in II, III, aVFPseudo R in V1

After adenosine injection

Congenital accessory pathway (Bundle of Kent)Orthodromic or antidromic AVRTUsually, p wave is seen inverted after QRS

Conduction through bundle of KentShort PR + delta wave + QRS Dominant R in V1-2 arrhythmia, syncope Wolff-Parkinson-White Syndrome

With P wave:Atrial tachycardia c varying blockAtrial flutter c varying blockMultifocal atrial tachycardiaWithout P wave:Atrial fibrillation

At least 3 morphologies of p waveVariable PR interval Chronic lung disease

1 2 3 2 4 2 5 1 4 2

Multiple micro-reentry circuit in atriumParoxysmal: heart failure, hypovolemia, sepsis, postoperativePermanent: structural atrial disease MS, HTN LAA-LAEP wave rate: 350-600 bpm in a character of Fibrillation waveQRS is usually irregular, except AF with 3rd deg. AV blockSlow, normo or rapid ventricular response

Identify P wave QRS Irregularly Irregular

VT is the MOST COMMONSVT with BBBAntidromic AVRT Criteria VT VT

PVC 3 Sustained VT (>30s): DefibrillateNon-sustained with hypotension: DefibrillateNon-sustained without hypotension: find the causeVentricular rate: 150-250/minAV dissociationFusion beatEscape beat

100% VT for sure

Monomorphic: single ectopic focusPolymorphic: multiple ectopic fociTorsade de pointes

Escape beatFusion beat

Polymorphic VT in long QTc (>0.45 sec)QRS axis

AF/Aflut with varying block withBBBWPW

1:1 AV conduction (bypass AV node) AV node blocker: adenosine, digoxin, diltiazem, verapamil

Regular rhythm with rate < 60 beat/min (45-59)Uniform P wavePR interval NOT PROLONGED MI , sick sinus syndromeHypothyroidismBeta blocker ******

SA node atrial depolarization AMISick sinus syndrome

PR 5 = Prolonged AV block 1st degree: PR prolong 5 2nd degree: - Mobitz I: PR prolong QRS 1 prolong - Mobitz II: PR QRS - 2:1 AV block: P-P-QRS (High grade)3rd degree: P QRS rate QRS Junctional () ventricular rhythm ()

PR = 6

Mobitz I: PR prolong QRS 1 prolong

Mobitz II: PR prolong QRS

2:1 AV block: P-P-QRS

P QRS rate QRS Junctional () ventricular rhythm ()

2:1 AV block

1st degree AV block, ST depression in V4-6, II, III, aVF, LVH with strain pattern

3rd degree AV block with complete RBBB

Hyper/hypokalemiaHyper/hypocalcemiaDigoxin intoxicationDextrocardiaMisplaced leads

Tall-peaked T: K = 5.5-6.0P wave : K = 6.5-7.5 Wide QRS: K = 7.5-8.0Sine wave: K > 8.0

Mx:10% Ca Gluconate 10ml in 10 minInsulin 5-10 U IV + 50% glucose 50 mlExcretory agent: diuretics, Kalimate

Flat T UST depressionT inversion

HyperCal: Short QTHypoCal: Long QT

block SVT with AV blockAF with AV blockAccelerated junctional rhythm (specific)Ventricular arrhythmiaMultifocal PVCs (Most common)VT, VFReversed check sign in ST segment

FeaturesRight axis deviationDominant R in V1, with declining heights in V2-6Positive p wave in aVRInverted p wave in I, aVL (DDx reversed limb electrode)

Positive P in aVR (RA involved)Inverted p in I, aVL: RA LAInverted p in II, III, aVF: RA LLAbsent II, or almost biphasic I: RA RL (unsure)Negative P in aVR (RA not involved)Inverted p in III only: LA LLAbsent III: LA RL (unsure)Nothing change: LL RL

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