Path of a cardiac impulse

Question 1

Describe the full path of one cardiac impulse

Answer 1

SA node- Atrial syncytium-junctional fibres-AV node-AV bundle- bundle branches-Purkinjean fibres-ventricular syncytium

Question 2

What is the cardiac cycle?

Answer 2

Change in heart pressure

Question 3

What is diastole?

Answer 3

Heart is relaxed fill with blood

Question 4

What is systole?

Answer 4

Heart is contracting blood expels

Question 5

How to record an ECG

Answer 5

Record of the electrical changes that occur during a cardiac cycle
From summed action potentials of many cardiac muscle cells- be detected through electrical currents in the body fluid

Question 6

What are all the components of an ECG

Answer 6

P wave, QRS complex, T wave

Question 7

What is the P wave?

Answer 7

First wave, corresponds to depolarization of the atria, leads to the contraction of the atria

Question 8

What is the QRS complex?

Answer 8

Depolarization of ventricles- leads to contraction of the ventricles
Repolarization of the atria occurs- hidden behind the larger ventricular events

Question 9

What is the T Wave?

Answer 9

Corresponds to ventricular repolarization- leads to ventricular relaxation

Question 10

What can the heart sounds be described as?

Answer 10

Lubb-dupp sound

Question 11

What does the first heart sounds lubb occur for?

Answer 11

Ventricles contract

AV valves are closing

Question 12

What does the second heart sounds dubb occur for?

Answer 12

Ventricles relax

aortic and pulmonary valves are closing

Question 13

What is a murmur?

Answer 13

Abnormal heart sound- due to a damaged valve