Introduction to the heart

Question 1

What are the capacities of the chambers of the heart?

Answer 1

Left atrium-100ml

Right atrium-110ml

Left ventricle-150ml

Right Ventricle-175ml

Question 2

What are the pressures of the greater vessels of the heart?

Answer 2

Aorta:100-120mmHg

Pulmonary artery:10-20mmHg

Vena Cava:5-10mmHg

Pulmonary Vein: 10-15mmHg

Question 3

Why is it important to know the pressure of the Vena Cava?

Answer 3

because it gives an indication of the central venous pressure of a patient which can be used to know if a certain patient will recover and is used a lot in emergency and ICU

Question 4

What is caused by high blood pressure in the pulmonary artery

Answer 4

pulmonary arterial hypertension

Question 5

Which valves are on the left and right side of the heart?

Answer 5

Right: -Tricuspid(AV) -Pulmonary(SL)

Left: -Mitral(AV) -Aortic(SL)

Question 6

What is regurgitation of a valve?

Answer 6

Valve cant close properly so blood flows backwards

Question 7

What is stonosis of valves?

Answer 7

valves harden and are more difficult to open

Question 8

What happens if you have valves replaced?

Answer 8

They are more likely to suffer from bacterial infections

Question 9

What are the nodes of the heart and function?

Answer 9

Sinoatrial node: -pacemake of the heart 60-100bpm

Atrioventricular node:

• 3 internodal pathways go to the right atrium and 1 to the left atrium -made of cardiac non muscle
• electrical activity comes down to AV node and stops as the AV node prevents electrical activity going further and regulates electrical activity
• slow calcium mediated action potential

Question 10

Where is the sinoatrial node located?

Answer 10

junction of the cristae terminalis-upper wall of right atrium and opening of superior vena cava

Question 11

Where is the AV node located?

Answer 11

TRINAGLE OF KOCH at the base of the right atrium

Question 12

What are the tracts in the heart?

Answer 12

BUNDLES OF HIS(specialised myocytes)->split into right and left bundle branches->goes on to form PURKINJE FIBRES which allows electrical conductance around the heart (go from the AV node)

INTERNODAL TRACTS -between the sinoatrial node and AV nde

Question 13

What cell are purkinje fibres made from?

Answer 13

Specialised conducting cells not myocytes

Question 14

What are the names of the coronary arteries?

Answer 14

Right coronary(in between the right atrium and right ventricle)

Left coronary splits into:

• Left Circumflex(curves round the left atrium)
• Left anterior descending (in between the left and right ventricle) this is the most common place in the heart to get a blockage=Myocardial infarction

Question 15

How can you detect where a myocardial infarction is?

Answer 15

using an ECG

Question 16

What are the names of the veins involved in the venous supply of the heart?

Answer 16

(Usually towards the posterior of the heart)

• Coronary sinus
• Great Cardiac Vein
• Middle Cardiac vein

Question 17

What is an example of a cardioselective beta blocker

Answer 17

Atenolol

Question 18

What are calcium channel blockers used for commonly and give example?

Answer 18

hypertension e.g.amlodipine

Question 19

What is an angiotensin receptor blocker? Give example?

Answer 19

losratan prevents vasoconstriction

Question 20

What is an ACE inhibitor? Give example

Answer 20

used before angiotensin receptor blocker to block the angiotensin converting enzyme=prevent vasoconstriction e.g.ramipril

Question 21

What is a thiazide-like diuretic? Give example?

Answer 21

reduce blood pressure by reducing blood volume e.g. chlorthalidone