Advanced Ecg Interpretation

Front 1

The normal path of impulse transmission throughout the heart

Back 1

Sinoatrial Node
Atrioventricular Node
Bundle of His
Bundle Branches (L & R)
Purkinje Fibres

Front 2

Identify each component of the ECG

Back 2

P Wave
P-R interval
QRS Complex
T Wave
Q-T interval
Sometimes a U wave

Front 3

The 5-Step Method of ECG Analysis

Back 3

1. Calculate the Heart Rate

2. Determine if the Ventricular Rhythm is regular or Irregular.

3. Measure the Width of the QRS Complex.
< 0.12 sec - (normal supraventricular origin)

4. Analyse the P Wave
(positive deflection, rounded shape, present befor QRS)

5. Measure the P-R Interval
0.12 - 0.20 sec

Front 4

Correct Lead Configuration
for Cardiac Monitoring

Einthoven's Triangle

Back 4

Bipolar Limb Leads I,II,III

Identify negative and positive electrodes

Front 5

Definition of 'Lead and 'electrode

Back 5

A lead is an electrical system used to record electrical activity. A lead is composed of a negative and a positive electrode (Bipolar), which sense the magnitude and direction of electrical impulses between the two electrodes.

Hint 5

As an impulse travels towards the positive electrode, a positive deflection (vector) is seen on the ECG while an impulse that travels away from the positive electrode is seen as a negative deflection on the ECG. (below the isolectric line)

Front 6

The normal speed of the ECG paper

Back 6

25 mm per second

Front 7

What both horizontal and vertical axes of the ECG represents

Back 7

Horizontal plane = Time

Vertical plane = Amplitude (voltage)

Front 8

The time representation of a
1mm box
on the ECG paper

Back 8

0.04 sec

Front 9

The time representation of a
5mm box
on the ECG paper

Back 9

0.20 sec

Front 10

The time representation of a
25mm box
on the ECG paper

Back 10

1 sec

Front 11

Three methods of calculating heart rate on the ECG

Back 11

1. Count back method
1 sq = 300bpm
2 sq = 150bpm
3 sq = 100bpm
4 sq = 75bpm
5 sq = 60bpm
6 sq = 50bpm

2. HR calculator/Ruler

3. 6 sec strip
Count R waves x 10 = 60sec
starting on line.

Front 12

Define ectopic complexes?

Back 12

Ectopic
Premature Contraction
Extrasystole

Anypart of the heart is able to depolarise earlier than it should, they can arise in the atria, A-V node or the ventricles.

Front 13

Identify this rhythm?

Back 13

Ventricular Tachycardia
VT
Defined by three of more consecutive PVC's occuring at a greater rate than 100 complexes per minute

Front 14

Identify this rhythm?

Back 14

Ventricular Fibrillation

VF is a death producing dysrhythmia in which electrical activity in the heart is chaotic due to multiple ectopic ventricular sites.

Its a quivering of the heart not allowing cardiac cells to depolarise and repolarise.

It does not pump blood , therfore circulation stops.

Front 15

The 5 Steps of ECG rhythm recognition

Back 15

1. Rate (60-100bpm)

2. Rhythm regularity
P-P interval & R-R interval

3. P wave
positive (upright) in lead ii and precedes each QRS complex, P waves should look alike

4. PR interval 0.12-0.20 sec and constant from beat to beat

5. QRS 0.04-0.12 sec

Front 16

Identify this rhythm

Back 16

A premature atrial complex

is an extra P-QRS-T complex consisting of an abnormal (sometimes normal) P wave followed by a normal or abnormal QRS complex, occurring earlier than the next expected beat of the underlying rhythm, usually a sinus rhythm. A PAC is generally followed by a non-compensatory period.

Hint 16

Types of PAC's

Infrequent PAC's (<5/min)
Frequent PAC's (>5/min)
Isolated PAC's (Single)
Atrial Tachycardia (>3 in a row)
Atrial Bigemity PAC's alternating with QRS of the underlying rhythm.

Atrial Trigemity/Quadrigemity
PAC's following every two or three QRS complexes of the underlying rhythm, respectively.

Front 17

Identify this rhythm

Back 17

Rate: Underlying rhythm
regularity: Irregular when PVC occurs
P Waves: of underlying rhythm
PR intervals: of underlying rhythm
QRS complexes: Wide >0.12 sec

Hint 17

A premature ventricular complex (PVC)

is an extra ventricular complex consisting of an abnormally wide and bizzare QRS complex that originates in an ectopic site in the ventricles, in the bundle branches, purkinji network, or ventricular myocardium. It occurs earlier than the next expected beat of the underlying rhythm and is usually followed by a compensatory pause.

Front 18

Identify this rhythm with the 5 steps of ECG rhythm recognition

Back 18

Rate: 150-250
Regularity: Regular
P Wave: Usually absent
PR interval: P'R interval equal <0.12 sec
QRS Complex: Normal, wide if conduction delay exists

Hint 18

Paroxysmal supraventricular tachycardia (PSVT)

is a dysrhythmia originating abruptly at the site of a rapid reentry circuit in the AV junction with a rate between 150-250 bpm. The PSVT may present as an AV nodal reentry tachycardia (AVNRT) or an AV reentry tachycardia (AVRT)

Front 19

Identify this rhythm using the 5 step method

Back 19

Rate: Atrial rate 350-600, ventricular rate 160-180 if AF uncontrolled; 60-70 if AF controlled or AV block is present

Rhythm: irregularly irregular

P Wave: No identifiable P waves, fibrillatory waves present; erratic, wavy baseline

PR interval: not measurable
QRS: normal (0.12 or <) but may be wide if an intraventricular conduction delay exists.

Hint 19

Atrial fibrillation

is a dysrhythmia arising in multiple ectopic atrial sites or sites of rapid reentry circuits in the aria, characterised by very rapid atrial fibrillation (f) waves and an irregular, often rapid ventricular response.

Front 20

Identify this rhythm using the 5 step method

Back 20

Rate: Atria 240-260, Ventricular 1/2 atrial rate or less
Regularity: Regular
P Waves: Normal P waves absent, F waves (sawtooth)
PR intervals: difficult to measure
QRS: Normal <0.12 sec, wide if conduction delay exists

Hint 20

Atrial Flutter

is a dysrhythmia arising in an ectopic pacemaker or the site of rapid reentry circuit in the atria, characterised by rapid atrial flutter (f) waves with a sawtooth appearance and, usually a slower, regular ventricular response.

Front 21

Identify this rhythm using the 5 step method

Back 21

Rate: 40-60
60-100= accelerated junctional rhythm,
>100= junctional tachycardia

Regularity: regular
P Waves: absent or inverted
PR interval: If present <0.12 sec
QRS: Normal, wide if conduction delay exists

Hint 21

Junctional Rhythm

ia s dysrhythmia originating in an escape pacemaker in the AV junction with a rate of 40-60 bpm. When less than three consecutive QRS complexes arising from the escape are present, they are called junctional escape beats or complexes.

Front 22

Identify this rhythm

Back 22

Paced Rhythm

2 Types= Fixed Rate & Demand

Fixed Rate, are designed to fire constantly at a preset rate without regard of the hearts own electrical activity.

Demand PM, have a sensing device that senses the hearts electrical activity and fires at a preset rate only when the hearts electrical activity drops below a predetermined rate.

Hint 22

Single Chamber Pacemakers:
Atrial Demand and Ventricular Demand

Dual Chamber Pacemakers:

Front 23

Identify this rhythm using the five step method

Back 23

Rate: normal

Rhythm: regular

P Waves: Normal in size and shape, one positive P wave befor each QRS

PR interval: Prolonged (>0.20) but constant

QRS Duration: Normal < 0.12 sec unless a conduction delay exists

Hint 23

First Degree AV Block

is a dysrhythmia in which there is a constant delay in the conduction of electrical impulses, usually through the AV node. It is characterised by abnormally long PR intervals that are greater than 0.20 sec and constant in duration.

Front 24

Identify this rhythm using the 5 step method

Back 24

Rate: Atrial rate is greater than the ventricular rate

Rhythm: Atrial regular (P's plot through on time); ventricular irregular

P Wave: Normal in size and shape; some P waves are not followed by a QRS complex

PR interval: Lengthens with each cycle, until a P wave appears without a QRS complex

QRS Duration: Normal <0.12 sec but is periodically dropped

Hint 24

Second Degree AV Block type i - Wencheback

Is a dysrhythmia in which there is a progressive delay following each P Wave until conduction is completely blocked. The sequence of increasing PR intervals and an absent QRS complex is repetitive.

Front 25

Identify this rhythm using the 5 step method

Back 25

Rate: Atrial rate is greater than the ventricular rate; ventricular rate is often slow

Rhythm: Atrial regular (P's plot through on time), ventricular irregular

P Wave: Normal in size and shape; some P waves are not followed by a QRS complex

PR interval: within normal limits or slightly prolonged but constant for the conducted beats; there may be shortening or the PR interval that follows a nonconducted P wave

QRS Duration: Normal <0.12 sec but periodically absent after P Wave

Hint 25

Second Degree AV Block type ii - Mobitz type ii

The conduction delay in this block occurs below the AV node, either at the bundle of His or the bundle branches. It is characterised by a constant PR interval befor conducted beats, with some beats not conducted at all. (more serious than type i)

Front 26

Identify this rhythm using the 5 step method

Back 26

Rate: Atria rate is greater than Ventricular rate, independent escape rhythm

Rhythm: Atria regular; ventricular rate regular, there is no relationship between the atrial and ventricular rhythms

P Wave: Normal in size and shape

PR interval: none - the atria and ventricles beat independently of each other.

QRS duration: Narrow or wide depending on the location of the escape rhythm
Narrow= junctional pacemaker
Wide = Ventricular pacemaker

Hint 26

Third Degree AV Block

Is the complete absence of conduction of the electrical impulses through the AV node, bundle of His or bundle branches, characterised by independent beating of the atria and ventricles.