Y1S1W8 Cardiovascular System

Question 1

Describe location of the heart

Answer 1

In the chest between the lungs, slightly tilted towards the left hip

Question 2

Main structures of the heart

Answer 2

Left side:
Pulmonary Vein, left atrium, left ventricle, Aorta (artery)

Right side:
Vena Cava, right atrium, right ventricle, Pulmonary arteries

Question 3

Describe the heart covering and heart wall

Answer 3

Pericardium (epicardium) covers the heart. This is composed of membranous layers which trap fluid between.

Heart wall sits beneath pericardium and is composed of 3 layers. (Epi, Myo, Endo). Primarily muscular (myocardium) which varies in thickness in different areas.

Question 4

Explain how blood circulates through the heart

Answer 4

Blood flows in a closed system (vascular). Heart connected to systemic and pulmonary circuit.

Veins normally carry deoxygenated blood from around the body.

Pulmonary vein carries oxygenated blood to left atrium (to be pumped around the body).

Question 5

Explain and name the main heart valves

Functions

Answer 5

ATRIOVENTRICULAR valves sit between atria & ventricles. These are TRIcuspid and BIcuspid.

SEMILUNAR valves sit between the ventricle and artery. These are pulmonary and aortic semilunar valves.

Function: To make sure blood flows in ONE DIRECTION

Open and close as a result of changing pressure. Held in place by chordae tendineae

Question 6

Describe the cardiac cycle

Answer 6

Deoxygenated blood from the body enters right atrium via the vena cava, filters into the right ventricle and is pumped out to the lungs via the pulmonary artery.

Oxygenated blood from the lungs enters the left atrium via the pulmonary veins, filters into the left ventricle and is pumped out to the body via the aorta.

Question 7

Explain how the heart sets ‘pace’

Answer 7

Via SAN - Sinoatrial Node - CONDUCTION, electrical impulses

Myocardium contracts, impulse from SAN spreads across atria causing contraction.

Impulse hits atrioventricular node and passes signal on to ventricles causing contraction.

Question 8

What is systolic pressure?

Optimum reading?

Answer 8

Pressure whilst beating (contraction)

> 140mmHg (more than)

Question 9

What is distolic pressure?

Optimum reading?

Answer 9

Pressure between beats/resting (relaxation)

<85mmHg (less than)

Question 10

Common Conditions:

Answer 10

Angina, heart attack, hypertension, high cholesterol, congestive heart failure, rhythm disorders, vascular problems

Question 11

Anti-anginals

Answer 11

Nitrates, Beta-blockers, Ca channel blockers

Question 12

Hypertension therapies

Answer 12

Vasodilators, Diuretics, ACE inhibitors

Question 13

Congestive heart failure treatments

Answer 13

ACE inhibitors, Diuretics, Cardiotonics, Vasoconstrictors

Question 14

Rhythm disorder therapies

Answer 14

Beta-blockers, Ca Channel blockers

Question 15

What is an ACE inhibitor?

Answer 15

Angiotensin Converting Enzyme produce angiotensin II (vasoconstrictor)

Inhibiting formation of angiotensin II reduces blood pressure.

Question 16

What is a Beta-Blocker?

Answer 16

Beta receptors are found in the brain, involved in sympathetic nervous system activity - leads to increased cardiac output.

Beta-Blockers = antagonist, reduce this effect, reducing blood pressure.

Question 17

What is an ACE inhibitor?

Answer 17

Angiotensin Converting Enzyme produce angiotensin II (vasoconstrictor)

Inhibiting formation of angiotensin II reduces blood pressure.

e.g. captopril

Question 18

What is a Beta-Blocker?

Answer 18

Beta receptors are found in the brain, involved in sympathetic nervous system activity - leads to increased cardiac output.

Beta-Blockers = antagonist, reduce this effect, reducing blood pressure.

e.g. atenolol, propranolol, bisoprolol

Question 19

What is a Calcium Channel Blocker?

Answer 19

Reduce influx of Ca2+ to myocardial cells therefore reducing contraction and promotes vasodilation.

e.g. amlodipine, verapamil