EKG Leads

Question 1

EKG Lead I

Answer 1

Bipolar lead

Only one L

Horizontal from R arm (-) to L arm (+)

Get a (+) deflection on the EKG for that lead when the forces are directed towards the L arm.

Question 2

EKG Lead II

Answer 2

Bipolar lead

Two Ls

R arm (-) to L leg (+)

Get a (+) deflection on the EKG for that lead when the forces are directed towards the L leg.

**Visualizes the P wave best (esp R atrial enlargement)

Question 3

EKG Lead III

Answer 3

Bipolar lead

Three Ls

L arm (-) to L leg (+)

Get a (+) deflection on the EKG for that lead when the forces are directed towards the L leg.

Question 4

EKG Lead aVR

Answer 4

Unipolar lead

All other limb leads = composite (-) reference

R arm (+)

Get a (+) deflection on the EKG for that lead when the forces are directed towards the R arm

Question 5

EKG Lead aVF

Answer 5

Unipolar lead

All other limb leads = composite (-) reference

L leg = (+)

Get a (+) deflection on the EKG for that lead when the forces are directed towards the foot.

Question 6

EKG Lead aVL

Answer 6

Unipolar lead

All other limb leads = composite (-) reference point

L arm lead = (+)

Get a (+) deflection on the EKG for that lead when the forces are directed towards the L arm.

Question 7

Upward or Positive deflection

Answer 7

Means that forces are directed towards the (+) pole of a lead

Question 8

Downward or Negative deflection

Answer 8

Means that forces are directed away from the (+) pole of that lead [towards the (-) pole of that lead]

Question 9

Magnitude of a deflection

Answer 9

Represents how parallel the electrical force is to the axis of the lead being examined

That is, parallel → large magnitude

oblique → medium magnitude

Question 10

Flat line on a lead

Answer 10

Represents an electrical force that is directed perpendicular to the lead being examined, and therefore does not register any activity by that lead.

Question 11

EKG Lead V1

Answer 11

Anterior lead - R ventricle

4^th intercostal space (ICS), 2 cm to the R of the sternum

**Visualizes L atrial enlargement on the P wave best

Question 12

EKG Lead V2

Answer 12

Anterior lead - R ventricle

4^th ICS, 2 cm to the L of the sternum

Question 13

EKG Lead V3

Answer 13

Lateral - towards to apex

In between V2 and V4

Question 14

EKG Lead V4

Answer 14

Lateral - at the apex

5^th ICS at L mid-clavicular line

Question 15

EKG Lead V5

Answer 15

Posterior - L ventricle

5^th ICS, L anterior axillary line

Question 16

EKG Lead V6

Answer 16

Posterior - L ventricle

5^th ICS, L midaxillary line