Download presentation
Presentation is loading. Please wait.
Published byBethanie McCarthy Modified over 9 years ago
1
Ulkumen Rodoplu, MD EuSEM ELECTROCARDIOGRAPHY
2
Plan A Normal ECG Basic ECG Waveform Initiation of Spread of Electrical Activation in the Hearth The Magnitude and Direction of the Activation Process Activation Vectors
3
Introduction - Essential tool in the investigation of heart disease. - No cardiological assessment is complete without a 12-lead ECG. - One hundred million ECGs are recorded worldwide each year.
4
History 19th century. The heart generated electricity. 19th century Augustus Waller, working in St Mary's Hospital in London: The first systematical approach about the heart from an electrical point-of-view. Augustus WallerSt Mary's Hospital London Willem Einthoven, working in Leiden, The Netherlands, invented the string galvanometer, which was much more precise than the capillary galvanometer that Waller used. Willem EinthovenLeidenThe Netherlandsgalvanometercapillary Einthoven assigned the letters P, Q, R, S and T to the various deflections, and described the electrocardiographic features of a number of cardiovascular disorders. He was awarded 1924 Nobel Prize for Physiology and Medicine for his discovery.1924Nobel Prize for Physiology and Medicine
5
Initiation and Spread of Electrical Activation in the Heart In normal circumstances the whole process begins in the sino-atrial node.
6
Initiation and Spread of Electrical Activation in the Heart SA Node normally initiates activation of the atrial myocardium AV Node transmits activation received from the SA Node to the common bundle HIS Bundle forms the electrical connection between the atria and the ventricles
7
Initiation and Spread of Electrical Activation in the Heart The right and left bundle branches run below the endocardial surfaces of their respective ventricles The Purkinje network spreads over the endocardial surfaces of the ventricles
8
The Basic ECG Waveform P wave - spread of electrical activation through the atrial myocardium. QRS Complex – spread of electrical activation through ventricular myocardium. T wave – electrical recovery of the ventricular myocardium.
9
Electrical Activity & ECG
10
P Wave < 0.10 sec. wide < 2.5 mm. amplitude (+)……DI, II, aVF (+) (-)… aVL (-)… aVR VI, biphasic or (-)
11
PR interval 0.12 – 0.20 sec
12
QRS Depolarisation of ventricles < 0.10 sec. wide
13
T Wave Repolarisation of ventricles 0.12-0.25 sec. wide (+)…DI, II, V2-6 (+) (-)…aVL, aVF (-)….aVR
14
Calculation of Rate
15
Activation Vectors - A vector is simply something which has magnitude and direction. - Direction in which the arrow points represents the direction of the vector. - Length of the arrow represents the magnitude of the vector. - The apparent magnitude of the activation wave will depend on the direction from which it is sensed.
16
Polarisation and Depolarisation - Activation is actually the process of depolarisation and the spontaneous spread of this process over the myocardial cells. - Resting, healthy mycardial cells are polarised. - The surface membrane of each cell has an accumulation of charges – positive ones on the outside and an equal number of negative ones on the inside.
17
The QRS Complex - The central oblong is the myocardial strip. - The arrow shows the depolarisation vector in magnitude and in direction. - The deflection recorded by each lead is shown at the side of that lead.
18
A Normal 12 - Lead Electrocardiogram
19
ECG Derivations Bipolar…DI, DII,DIII Unipolar…aVR, aVL, aVF Precordial….V1….V6
20
Precordial Electrodes
21
Einthoven Triangle
22
A Normal Vectorcardiogram
23
Electrical Axis
24
Electrical Axis-Triaxial Method
25
Electrical Axis- Hexaxial Method
26
Electrical Axis-Practical Method I,II,III,aVF.. QRS(+).... Normal I…QRS(-), aVR…QRS(+)…RAD II,III,aVF.. QRS(-)....30º LAD
27
Normal ECG Leads
28
Normal Sinus Rhytm
29
Sinus Tachycardia
30
Sinus Bradycardia
31
Sinus Arrhytmia
32
Atrial Escape Beat
33
Nodal Escape Beats
34
Nodal Rhythm in Complete AV Block
35
Atrial Tachycardia
36
Supraventricular Tachycardia
37
Atrial Flutter – atrial rate 300
38
Atrial Flutter – 2:1 Conduction, Atrial rate 300
39
Ventricular Premature Contractions
40
Multiform VPBs
41
Ventricular Couplets
42
Ventricular Flutter
43
Ventricular Fibrilation
44
First degree AV Block
45
Second degree AV Block Wenckebach or Mobitz Type I
46
Second degree AV Block Mobitz Type II
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.