Electrocardiogram

Electrocardiogram

Electrocardiogram

Flow of Current Around the Heart During the Cardiac Cycle

Electrocardiogram

Electrocardiogram

Electrocardiogram

60 R-R

1 RateHeart

Electrocardiogram

Findings from ECGThe 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).

Electrocardiogram

Electrocardiographic Leads (Frontal plane)

Bipolar Limb Leads

Augmented Unipolar

Limb Leads

ElectrocardiogramEinthoven's

LawI + 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.

Electrocardiogram

Electrocardiographic Leads (Horizontal plane)

Electrocardiogram

Vectorial Analysis of Electrocardiograms

Electrocardiogram

Vectorial Analysis of Electrocardiograms

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