This document discusses cardiac rhythms and electrocardiogram (ECG) interpretation. It provides normal and abnormal heart rate ranges for the sinoatrial node, atrioventricular node, and bundle branches. It also describes ECG patterns such as sinus rhythm, arrhythmias, conduction abnormalities, myocardial infarction, and other cardiac conditions. Measurement techniques for rate, intervals, and waveform analysis on ECG strips are outlined.

1. By M.elkhatib CIN

3.  SA node- 60-100bpm
 AV node- 40-60bpm
 Bundle branches- 20-40bpm

6.  Regular - RR interval constant
 Basically regular – premature
atrial/ventricular ectopic
 Regularly irregular - RR interval variable but
 with a pattern
 Irregularly irregular - RR interval variable with
no pattern

7.  Sinus Rhythm
 Sinus Brady
 Sinus Tachy
 Atrial Tachy
 Atrial Flutter
 Junctional Tachy
 AVNRT/AVRT
 VT
 1 & 3 degree HB

9.  Sinus arrhythmia
 Atrial fibrillation
 Wenkebach
 Mobitz 2
 VF

10.  Horizontally
One small box - 0.04 s
One large box - 0.20 s
 Vertically
One large box - 0.5 mV

12.  Small boxes
 Number of small boxes between RR or PP
 1500 divide by number of small boxes
 Example 15 small boxes between the peaks
 of two RR - 1500/15 = HR 100bpm.

13.  Number of large boxes between 2 RR/PP
intervals
 Divide 300 by the number of large boxes
Example
 5 large boxes between 2 RR complexes
 300/5 =60bpm

14.  Quick and dirty method great for an irregular
rhythm
 Measure 6 second strip and x by ten.

15.  Sinus Brady
 Sino atrial arrest
 Wenkebach
 Mobitz type 2
 CHB

16.  Sinus Tachy
 Atrial Tachy
 A flutter
 Atrial fibrillation
 VT
 VF
 Junctional Tachy
 Nodal re-entrant Tachy
 Re-entrant Tachy

17.  Does a P wave precede every QRS
 Is it positive or negative in the correct leads
 Do all the p waves look alike
 What is the shape of the p wave
 What is the ratio of p waves to QRS
complexes
 Normal p waves upright (except AVR) round
with 1:1ratio

18.  P Mitrale
 A wide bifurcated P - wave
 Left atrial enlargement

19.  P Pulmonale
 Tall P wave
 Right atrial hyptrophy

20.  AV junctional rhythm
 Atrial fibrillation
 Atrial flutter
 Sino-atrial block

21.  Dextrocardia
 Incorrectly placed limb leads
 Ectopic beats

22.  Beginning of P wave to the beginning of QRS
 Normal = 0.12 -0.20 secs
 No more than 5 small squares

23.  PR interval > 0.20 sec
 secondary to drugs (digoxin/beta blockers)
 Hypokaleamia
 Congenital abnormalities (ASD, TGA)

24.  First degree AV Block

25.  <0.12 secs
 Wolf Parkinson White syndrome (ventricular
muscle stimulated early)
 Junctional rhythm
 Dissociated beats (CHB)

26.  Wenkebach
 Wandering pacemaker
 Premature atrial beats
 AV dissociation

27.  The length of time taken to depolarise the
ventricles
 <0.12 secs (3 small squares)
 Q - first negative deflection
 R- first positive deflection
 S negative deflection after R
 Any upward deflection after the R above the
isoelectricline is classed as another R

28.  QRS - 0.12 secs or greater
 Common cause BBB
 Abberant conduction
 Think VT, VF, CHB

29.  Dead or stunned myocardial tissue
 Usually permanent
 Can be reversed with early intervention
 More than 1mm in depth
 0.02 secs or greater in V1-V2
 0.04 secs or more and greater than one-third of the
R wave (although their is much dispute over this)

30.  Reflects length of time from the beginning of
ventricular depolarisation to the end of repolarisation
 QT interval corrected for heart rate variability
 The ECG machine corrects this
 The corrected figure is called the QTc
 Should be no more than 440ms
 Slight variation in peadiatrics depending on age

31.  Inherited
 Medicine induced- amioderone, sotolol
 Hypocalceamia, hypokaleamia,hypomagnesia
 Induce torsades de points.

32.  Digoxin therapy
 Hypercalacaemia

33.  Represents recovery or repolarisation of the
ventricles
 Measured from the end of the QRS to the
beginning of the T wave
 The ST is normally isoelectric

34.  ST elevation-MI (STEMI)
 ST Depression (NSTEMI)

35.  Pericarditis
 Angina
 Hyperkalemia

36.  Digoxin therapy
 Tachycardia
 Hypokaleamia
 BBB
 Ectopics
 Cardiomyopathies

37. • Reflects repolarisation or ventricular muscular
relaxation ,T wave changes seen in:
 MI
 Ischemia
 electrolyte imbalances
 medications
 pericarditis
 Cardiomyopathies

39.  Upright round wave seen in lead II after
Twave and before the next P wave
 Not clearly understood
 Associated with hypokaleamia, amioderone
& digoxin

40.  The general flow of electrical activity of the
heart
 It relates to the flow of depolarisation wave
through the heart
 This can change with position of the heart
 Generally related to changes in electricalflow

42.  Left ventricular hypertrophy
 LBBB - bifasicular block
 LBBB + 1st degree HB - trifasicular block
 Mechanical shift of the heart
 Normal variant

43.  Right Ventricular Hypertrophy
 RBBB
 Dextrocardia
 Mechanical shift
 Normal variation