1. ElectrocardiogramElectrocardiogram

2. ElectrocardiogramElectrocardiogram

3. ElectrocardiogramElectrocardiogram Flow of Current Around the Heart During the Cardiac Cycle

4. ElectrocardiogramElectrocardiogram

5. ElectrocardiogramElectrocardiogram

6. ElectrocardiogramElectrocardiogram

7. ElectrocardiogramElectrocardiogram Findings from ECG The anatomical orientation of the heart The relative sizes of its chambers The various disturbances of rhythm Conduction, the extent and location of ischemic damage to the myocardium and its progress The effects of altered electrolyte concentrations The influence of certain drugs (notably digitalis, antiarrhythmic agents, and Ca ++ channel antagonists). The anatomical orientation of the heart The relative sizes of its chambers The various disturbances of rhythm Conduction, the extent and location of ischemic damage to the myocardium and its progress The effects of altered electrolyte concentrations The influence of certain drugs (notably digitalis, antiarrhythmic agents, and Ca ++ channel antagonists).

8. ElectrocardiogramElectrocardiogram Electrocardiographic Leads (Frontal plane) Bipolar Limb Leads Augmented Unipolar Limb Leads Augmented Unipolar Limb Leads

9. ElectrocardiogramElectrocardiogram Einthoven's Law I + III = II Einthoven's Law I + III = II Calculation of mean QRS vector. In each lead, distances equal to the height of the R wave minus the height of the largest negative deflection in the QRS complex.

10. ElectrocardiogramElectrocardiogram Electrocardiographic Leads (Horizontal plane)

11. ElectrocardiogramElectrocardiogram Vectorial Analysis of Electrocardiograms

12. ElectrocardiogramElectrocardiogram Normal direction of the mean QRS vector is generally said to be –30 to +110 degrees