E C G

DR.CH PAVAN KUMAR MBBS

CHAKRADHAR HOSPITALS.

WHAT IS ECG

HOW TO TAKE ECG

REPORTING OF ECG

WHAT IS ECG

E C G THE CAMERA

• A noninvasive electrocardiographic

representation of biophysiological

status of myocardium .

• ECG is the simplest way to take the

photograph of heart in different

directions to get a clear picture of it .

• Current flowing in the heart via the pacemakers to heart is to be recorded via the leads.

V = iR ohms law• Current (i) is low but with high resistance the

voltage outcome is made too large so that it can be recorded .

6

Normal Impulse Conduction

Sinoatrial node

AV node

Bundle of His

Bundle Branches

Purkinje fibers

HOW TO TAKE IS ECG

Einthoven’s triangle

LEADS

• Unipolar leads –V1 ,V6

• Bipolar leads– I ,II,III –VL ,VR ,VF

–aVL ,aVR ,aVF

How to read ECG

STANDARDISATION

Rate Number of large boxes divided by 300. 300,150,100,80,75,60,50.

Rate 150bpm

• Sinus rhythm–P wave followed by QRS complex in

lead II, III, aVF, V5, V6 • Ventricular rhythm• Fibrillation• Flutter

Rhythm

Rhythm Sinus rhythm

AXIS• This is the vector of the heart in toto ,hence

in simple terms it can be deducted by the lead I, aVF

LEAD AXIS AXIS AXIS AXIS

I + - - +aVF + - + -

REPORT NORMAL EXTREME RAD

RAD LAD

AXIS

R A D- ve

+ ve

CHAMBERS• RIGHT ATRIUM : Height in leads V1 ,II.

• LEFT ATRIUM : Width in leads V1 ,II.• RIGHT VENTRICLE : If R > S for 1 small square in

V1.• RVH with STRAIN : RVH with T wave inversion• Left ventricle : Cornell Voltair Crieteria – aVL “R” + V3 “S” > 20 in female or >28 in males

• LVH with STRAIN : LVH with T wave inversion

CHAMBERS

NORMAL CHAMBERS

RIGHT ATRIUM : Height of P leads V1 ,II.LEFT ATRIUM : Width of P in leads V1 ,II.

RIGHT VENTRICLE : If R > S for 1 small square in V1.

Left ventricle : Cornell Voltair Crieteria aVL “R” + V3 “S” > 20 in female or >28 in males

INTERVALS• P wave : 0.2 seconds• PR interval : 0.12 -0.2 seconds• QRS complex : 0.06 – 0.10

seconds• QT interval : less than half of

the RR interval• ST interval : • ST character• T wave : • R – R progression :

ARTIFACTS AND

ERRORS

To do• Patient to be in rest.• Respirations should not be voluntarily to

intense .• See electrodes are not loose.• Shave the hair if possible at electrodes area .• Place nothing on the bed ,don’t touch the bed

while taking ECG .• Maitain the paper speed ,don’t change default

settings

Effect of reversing electrodes RL

Effect of poor electrode contactbizarre QRS

Effect of overcalibration

Effect of pattern of respiration

Effect of stray potentials

Effect of electrical interfernce

RATE :RHYTHM :CHAMBERS :INTERVALS AND SIGNIFICANCE :

76 BPMSINUSNORMAL NORMAL

NORMAL ECG

RATE :RHYTHM :CHAMBERS :INTERVALS AND SIGNIFICANCE :

150 BPMSINUSNORMAL NORMAL

SINUS TACHYCARDIA ECG

Exercise, Anxiety, Fever, Hypoxemia,Hypovolemia, Or Cardiac Failure.

RATE :RHYTHM :CHAMBERS :INTERVALS AND SIGNIFICANCE :

48 BPMSINUSNORMAL NORMAL

SINUS BRADYCARDIA ECG

In acute MI, it may be protective and beneficial or the slow rate may compromise cardiac output. Certain medications, such as beta blockers, may also cause sinus bradycardia.

MYOCARDIAL INFARCTION

ST segment elevation 1 mm in the limb leads and 2 mm in the chest leads

Q

?

ANTERIOR MI

?

LATERAL MI

?INFERIOR MI

RATE :RHYTHM :CHAMBERS :INTERVALS AND SIGNIFICANCE :

150 BPMSINUS,SINUS PAUSENORMAL NORMAL

SINUS PAUSE ECG

Cardiac output may decrease, causing syncope or dizziness..

RATE :RHYTHM :CHAMBERS :INTERVALS AND SIGNIFICANCE :

76 BPMSINUS,DROPPED BEATNORMAL NORMAL

DROPPED BEAT ECG

RATE :RHYTHM :CHAMBERS :INTERVALS AND SIGNIFICANCE :

150 BPMNO P WAVE? NORMAL NO P WAVE,NO PR

SUPRAVENTRICULAR TACHYCARDIA ECG

RATE :RHYTHM :CHAMBERS :INTERVALS AND SIGNIFICANCE :

300 BPM,IRREGULAR ? SINUS? NORMAL NO P WAVE,NO PR

PAROXYSMAL SVT ECGSudden onset of SVT

RATE :RHYTHM :CHAMBERS :INTERVALS AND SIGNIFICANCE :

ATRIA :300;VENTRICULAR 100 ? SINUS? NORMAL PR VARIALBLE

ATRIAL FLUTTER ECGSudden onset of SVT

RATE :RHYTHM :CHAMBERS :INTERVALS AND SIGNIFICANCE :

ATRIA : >350 ;VENTRICULAR 60-150 . NOT SINUS? NORMAL PR NONE

ATRIAL FIBRILLATION ECG

Irregular R-R intervals

RATE :RHYTHM :CHAMBERS :INTERVALS AND SIGNIFICANCE :

20. NOT SINUS? NORMAL PR NONE

IDIOVENTRICULAR RHYTHM ECG

Irregular R-R intervalsagonal rhythm

RATE :RHYTHM :CHAMBERS :INTERVALS AND SIGNIFICANCE :

70. NOT SINUS WHEN PVC OCCURS? NORMAL PR NORMAL ,QRS BIZARRE

PREMATURE VENTRICULAR CONTRACTION ECG

PREMATURE VENTRICULAR CONTRACTION ECG

VENTRICULAR TACHYCARDIA ECG

PULSELESS ELECTRICAL ACTIVITY (PEA) ECG

• pUlmonary Embolism, MI, Acidosis, Tension Pneumothorax, Hyper- and Hypokalemia, Cardiac Tamponade, Hypovolemia, Hypoxia,hypothermia, and Drug Overdose (I.E., Cyclic Antidepressants, Beta Blockers, Calcium Channel Blockers, Digoxin).

ASYSTOLE ECG

• RULE OUT V FIB.• SEE IT NOT LESS THAN TWO LEADS .

Atrial pacemaker spike • Ventricular pacemaker spike

Pacemaker spike

Single-Chamber Pacemaker Rhythm—Ventricular

Dual-Chamber Pacemaker RhythmAtrial and Ventricular

SUMMARY• WHAT IS IT ?

• HOW IS IT ?

• HOW TO DO IT ?

• WHEN TO DO IT ?

• HOW TO NOT DO IT ?

• WHY SHOULD I DO IT ?

• WHAT DOES IT ?

• IS ECG EVERYTHING ?

• LEAR A LOT MORE……..