ECG.pptx
- 1. ELECTROCARDIOGRAM Dr Manjiri Honap Ist M.D.S. Department of Conservative Dentistry and Endodontics 1
- 2. Learning objectives Definition of Electrocardiogram What is the purpose of recording it? Terminologies used during ECG recording (Leads, waves, segments, interval, ECG paper) Calculate Heart rate and evaluate rhythm Case studies and Quiz Demonstration video summary Abbreviations used- Electrocardiogram - ECG 2
- 3. What is ECG? Graphic record of electrical activity of heart which is obtained by placing electrode on body surface that records voltage differences generated by heart 3
- 4. Electrocardiography and Electrocardiograph Electrocardiography is a method of recording ECG Wile electrocardiograph is a machine that records ECG which amplifies and gives a plot of voltage as a function of time 4
- 5. How does the surface electrode record the activity of heart? Human body is a volume conductor ECG recorded at body surface is an algebraic sum of action potential of individual cardiac muscle fiber 5
- 6. What Is the purpose of recording ECG? Anatomical orientation of heart Relative size of chambers Disturbances of rhythm and conduction Ischemia of myocardium if present Location and extent of myocardial infarct 6
- 7. Which all patients you will advise ECG in your Dental office? • The patients undergoing any major surgical procedure • Previous history of any cardiac disease • The patients which you are going to treat under General Anesthesia 7
- 8. Terminologies used during ECG recording 8
- 9. Electrode and Leads • Electrode is a metal plate used to detect electrical currents of heart in any location • ECG lead shows different voltages recorded by electrodes • A standard ECG is recorded with 12 leads • Where does the 12 lead come from? • Leads are placed in 2 different planes perpendicular to each other 9
- 10. 10 12 leads Frontal plane or limb leads (6) Bipolar Unipolar Transverse plane or chest leads (6) Unipolar
- 11. Frontal or limb leads or hex axial leads 11 Lead I, II, III Bipolar Avr, Avf, Avl Unipolar
- 12. Einthoven's triangle Bipolar limb leads Lead I Between right arm and left arm Lead II Between left foot and right arm LEAD III Between left foot and left arm Right foot is a grounded electrode 12
- 13. Unipolarlimbleads • AVR, AVL, AVF • Here A stands for augmented V stands for unipolar • These are exploring electrodes while • The reference point or an indifferent electrode is connected to right arm, left arm and left leg through the high resistance which is called as Wilson’s terminal which is maintained at zero potential 13