Notes on EKG and its Leads

Introduction

• The EKG (Electrocardiogram) consists of 12 leads.
• These leads observe the depolarization wave across the heart.

Einthoven's Leads

• Lead I: Observes from the left arm, designated as 0 degrees.
• Lead II: Observes from +60 degrees.
• Lead III: Observes from +120 degrees.

Augmented Leads

• aVR: Observes from the right arm at +120 degrees.
• aVL: Observes from -30 degrees.
• aVF: Observes from below at +90 degrees.

Orientation of the Leads

• All mentioned leads are seen in a frontal plane, as if the body were upright.

Precordial Leads

• They are placed on the chest, cutting the heart in a transverse or sagittal section.
• V1 to V6: Start from the right sternal border and wrap around towards the axilla.

Interpretation

• All the leads (I, II, III, aVR, aVL, aVF, V1 to V6) are printed on paper or appear on screens for interpretation.