Cardiac Axis

Question 1

What 2 leads are good for determining the cardiac axis?

Answer 1

I and aVF

Question 2

What is the cardiac axis if lead I is +ve and aVF is -ve?

Answer 2

Left axis deviation

Question 3

What is the cardiac axis if both lead I and aVF are -ve?

Answer 3

Indeterminate axis

Question 4

What is the cardiac axis if both lead I and aVF are +ve?

Answer 4

Normal axis

Question 5

What is the cardiac axis if lead I is -ve and aVF is +ve?

Answer 5

Right axis deviation

Question 6

What are the ranges for the axis?

Answer 6

Normal = -30 - 90
Right AD = 90 - 180
Left AD = -30 - -180

Question 7

List 5 possible causes of right axis deviation?

Answer 7

Respiratory inspiration
Right ventricle hypertrophy
Right bundle branch block
Dextrocardia
Ventricular ectopi

Question 8

List 5 possible causes of left axis deviation?

Answer 8

Expiration
Left bundle branch block
Emphysema
Hyperkalaemia
Congenital lesions