Cardiovascular System Physiology

Front 1

Name the four components of the conduction system of the heart.

Back 1

1) SA node

2) AV node

3) Bundle of His

4) Purkinjee fibers

Front 2

What is the main function of the conduction system?

Back 2

Conduction of the heart beat.

Front 3

Which component of the conduction system is called the "Pace maker"?

Back 3

SA Node.

Front 4

The pathway of conduction of an impulse in the heart muscles.

Back 4

SA node → Atria → AV node → Bundle of His → Purkinje Fibers → Ventricles

Front 5

Define the cardiac cycle.

Back 5

It refers to the sequence of events that occur during one complete heartbeat.

Front 6

Diastole

Back 6

Relaxation of heart chambers.

Front 7

Systole

Back 7

Contraction of heart chambers.

Front 8

Atrial Diastole

Back 8

The period when both left and right atria are relaxed and receiving blood.

Front 9

Ventricle Diastole

Back 9

During this stage, the ventricles are relaxed and receiving blood from both left and right atrium.

Front 10

Atrial Systole

Back 10

During this period the atrial muscles contract to push 30% of remaining blood into ventricles. During this period the AV valves are open but semilunar valves are closed.

Front 11

Ventricular Systole

Back 11

1) The increased pressure in ventricles shut the AV valves to prevent back flow of blood into atria.

2) The semilunar valves are opened due to high pressure in ventricles. The ventricular muscles contract and push the blood into aorta and pulmonary artery.

3) At the end of the ventricular systole, the semilunar valve shut close to prevent back flow of blood into ventricles.At the same time, the both left and right atrium relax and start receiving blood from veins.

Front 12

During ventricular systole what event happens first?

Back 12

The first event during this period is - the increased pressure in ventricles shut the AV valves to prevent back flow of blood into atria.

Front 13

Closure of which valves is responsible for making the first heart sound?

Back 13

AV valves

Front 14

Closure of which valves is responsible for making the second heart sound?

Back 14

Semilunar valves.

Front 15

What are heart murmurs?

Back 15

Abnormal heart sounds that are produced due to abnormal blood flow in the heart.

Front 16

What is valvular insufficiency?

Back 16

The leakage of AV valves when they fail to close completely.

Front 17

What does mitral valve or bicuspid valve leakage lead to?

Back 17

Left side congestive heart failure.

Front 18

What does tricuspid valve leakage lead to?

Back 18

Right side congestive heart failure.

Front 19

What is valvular stenosis?

Back 19

When semilunar valves fail to open completely.

Front 20

Define cardiac output.

Back 20

The volume of blood pumped by each ventricle per minute.

Front 21

Cardiac output depends on what factors?

Back 21

The heart rate and stroke volume (volume of blood pumped /beat).

Front 22

Which component of the nervous system controls the rate of heartbeat?

Back 22

The autonomic nervous system.

Front 23

What is the effect of parasympathetic stimulation on the heart rate and coronary blood flow?

Back 23

It slows down the heart rate (bradycardia) by decreasing the force of contraction of heart muscles and also decreases the blood flow to the coronary arteries.

Front 24

What is the effect of sympathetic stimulation on the heart rate and coronary blood flow?

Back 24

It speeds up the heart rate (tachycardia) and blood flow to the coronary arteries. The sympathetic stimulation causes contraction and relaxation to occur quicker and more efficiently, so the heart rate increases.

Front 25

Define stroke volume.

Back 25

It depends on the contractibility of heart and ventricular filling.

Front 26

What is the Sterling Law of the Heart?

Back 26

The greater the diastolic filling, the greater the cardiac output.

Front 27

What is Bainbridge Reflex?

Back 27

Increased right atrium blood pressure (or increased blood pressure in vena cavae returning the blood to right atrium) will increase the heart rate and therefore stroke volume.

Front 28

What is pulmonary edema?

Back 28

Fluid build up in the lungs.

Front 29

Define blood pressure.

Back 29

The pressure that the blood exerts on the vessel wall.

Front 30

Name the device used to measure the blood pressure.

Back 30

Sphygmomanometer.

Front 31

Systolic Pressure

Back 31

Peak pressure obtained during ventricular systole with each cardiac ejection.

Front 32

Diastolic Pressure

Back 32

Lowest pressure reached in the arteries during ventricular relaxation.

Front 33

Pulse

Back 33

The wave of systolic pressure that starts at the ventricles and spreads throughout the arterial network.

Front 34

Blood flow in vessels depends on what two factors?

Back 34

The change in blood pressure and the resistance of a given vessel.

Front 35

What structure in the arterial network controls the blood flow into the capillaries?

Back 35

The arterioles at the end of arterial network regulate the flow of blood in to capillaries.

Front 36

Mean Arterial Pressure depends on what two factors?

Back 36

The cardiac output (CO) and total peripheral vascular resistance (TPR).

Front 37

The P-wave of the ECG represents what cardiac event?

Back 37

Atrial depolarization.

Front 38

The QRS-complex of the ECG represents what cardiac event?

Back 38

Ventricular depolarization.

Front 39

The T-wave of the ECG represents what cardiac event?

Back 39

Ventricular repolarization or ventricular diastole.

Front 40

What are the 4 uses of the ECG?

Back 40

1) Monitoring the patient during and after surgery.

2) Detects enlargment of atria and ventricles.

3) Diagnosis of cardiac arrhythmias.

4) Diagnosis of cardiac diseases like endocarditis, myocarditis or tumors.