The Cardio Vascular System

Question 1

Vasodilation

Answer 1

widening of blood vessels as a result of the relaxation of the blood vessel’s muscular walls.
Vasodilation is a mechanism to enhance blood flow to areas of the body that are lacking oxygen and/or nutrients.

Question 2

vasoconstriction

Answer 2

is the narrowing (constriction) of blood vessels by small muscles in their walls. When blood vessels constrict, blood flow is slowed or blocked.
Vasoconstriction may be slight or severe. It may result from disease, drugs, or psychological conditions

Question 3

How Blood Clots -Haemostasis

Answer 3

Vasoconstriction
Platelets become sticky and adhere to the damaged wall

Platelet Plug formation
Platelets clump together attracting more platelets forming a temporary seal

Coagulation ( Blood Clotting)
Clotting factors activate each other in a specific order

Fibrinolysis
This is the process of healing the damaged blood vessel

Question 4

Tunica Adventitia

Answer 4

outer layer, fibrous tissue, supports and protects the blood vessel.

Question 5

Tunica Media

Answer 5

middle layer of smooth muscle and elastic tissue.

Question 6

Tunica Intima – or endothelium.

Answer 6

Smooth lining, one cell in thickness.

Question 7

What does anastomosis mean?

Answer 7

Joining of 2 tubes (ulnar and radius arties do this)

Question 8

What vertebrae does the thoracic aorta become the abdominal aorta

Answer 8

T12

Question 9

Arteries for upper limbs?

Answer 9

Ascending aorta -> Arch of aorta -> brachiocephalic trunk -> Subclavian artery -> axillary artery -> brachia artery -> Radial artery/ulna artery -> palmer arch

Question 10

Arteries for abdominal

Answer 10

Ascending aorta -> Arch of aorta -> Descending thoracic aorta -> abdominal aorta -> Coeliac axis/trunk and Superior Mesenteric Artery and Inferior Mesenteric Artery

Question 11

What vertebrae is the coeliac trunk at?

Answer 11

T12

Question 12

What vertebrae is the Superior Mesenteric Artery at?

Answer 12

L1 and L2

Question 13

What vertebrae is the Inferior Mesenteric Artery at?

Answer 13

L3

Question 14

Organs and their arteries

Answer 14

Diaphragm – phrenic artery
Stomach – Gastric artery
Liver        -  Hepatic artery
Pancreas – Pancreatic artery
Spleen    -  Splenic artery
Suprarenal / adrenal glands 
Kidneys  -  Renal arteries
Gonads   - Uterine or testicular arteries 
Lumbar (usually 4 pairs)

Question 15

Arteries for the lower limb?

Answer 15

At the end of the aorta it divides into 2 common iliac arteries (internal iliac artery for organs in the pelvis) and external iliac artery -> femoral artery -> popliteal artery/fossa -> Anterior/posterior tibial artery and peroneal artery -> plantar arch

Question 16

What vertebra is the common iliac artery at? wherein the pelvis?

Answer 16

L4, in front of the SIJs

Question 17

Arteries for head

Answer 17

Ascending aorta -> Arch of aorta -> brachiocephalic trunk -> common carotid artery (internal skull/external face) // Subclavian artery -> Vertebral arteries (to the brain)

Question 18

Interior of Heart

Answer 18

Divided into Right and Left sides by a septum

Each side is divided by an atrioventricular valve into an upper atrium and a lower ventricle

Question 19

What side is the tricuspid valve?

Answer 19

Right

Question 20

What side is the Bicuspid valve or Mitral Valve?

Answer 20

Left

Question 21

What holds the valves

Answer 21

Flaps of the valves are held by chordae tendineae, which fasten to the papillary muscles.
The papillary muscles are tiny extensions from the inner wall of the heart.

Question 22

Pericardium has 2 sacs 2 sacs
Fibrous pericardium
Serous pericardium
What does each do

Answer 22

Fibrous pericardium
Continuous with the tunica adventitia.
Attached to diaphragm
Protects and prevents over distention of the heart

Serous pericardium
Folded double layer around the heart – like the pleura in the lungs.
Inner layer is firmly attached to the myocardium.
Outer layer is attached to the fibrous pericardium.
20mls of pericardial fluid in between – lubricates the space, so the heart doesn’t rub against the fibrous sac.

Question 23

Myocardium facts?

Answer 23

Striated muscle, not under voluntary control
Cells are arranged in a continuous sheet, allowing the whole heart to contract in a co-ordinated and efficient manner
Network of fibres run between that transmits the hearts electric signals
Thickest at the apex, thins towards the base
Thickest in the left ventricle as this has to push the blood around the whole body.

Question 24

Endocardium facts?

Answer 24

Lines the chambers and valves

Flattened epithelial cells that are continuous with the lining of the blood vessels

Question 25

Blood flow in the heart

Answer 25

2 largest veins – superior vena cava (SVC) and inferior vena cava (IVC) flow into the Right Atrium (RA) This increases pressure in the RA – opening the tricuspid valve Blood enters the Right Ventricle (RV) The pressure in the RV increases, the tricuspid valve shuts, the ventricle contacts and pushes blood out into the Pulmonary Trunk, which divides into the Right and Left Pulmonary Arteries The exit is guarded by the pulmonary valve

Question 26

Pulmonary Circulation

Answer 26

Blood goes to the lungs, where gaseous exchange happens. CO2 is removed and O2 in taken in. 2 Pulmonary Veins then carry blood back to the Left Atrium (LA) This increases pressure in the LA – opening the Bicuspid valve Blood enters the Left Ventricle (LV) Pressure in the LV increases, the Bicuspid valve shuts

Question 27

The Blood Supply to the Heart

Answer 27

Heart is supplied by Right and Left Coronary Arteries -which arises immediately off the aorta as it leaves the left ventricle. 5% of the blood pumped from the heart, goes to these arteries. Drained by coronary sinus that empties into the right atrium.

Question 28

The Conducting System

Answer 28

The heart generates its own electrical impulses. Its is supplied with both sympathetic and parasympathetic nerve fibres which can increase and decease the heart rate respectively It also responds to certain hormones, including adrenaline and thyroxine.

Question 29

Sinoatrial node

Answer 29

Sinoatrial node (SA node) is a small collection of specialised cells Found in wall of the RA near the opening of SVC It generates an electrical impulse faster that any other part and is known as the pacemaker of the heart 60 – 90 times per minute The impulse from the SA arrives at the atrioventricular node at 0.1 secs later

Question 30

Atrioventricular node

Answer 30

The atrioventricular node (AV node) is a small mass of neuromuscular tissue in the wall of the atrial septum near the atrioventricular valves It transmits the electrical signals from the atria to the ventricles. 40 – 60 beats per minute This takes 0.1 seconds – allowing the atria to finishing contacting before the ventricles do.

Question 31

Atrioventricular Bundle

Answer 31

``` Atrioventricular Bundle (AV Bundle or Bundle of His) is a mass of specialised fibres that come from the AV node. They pass through to the ventricles and divided into right and left branches Within the ventricular myocardium they divided into the Purkinje Fibres ``` The AV bundle, bundle branches and Purkinje fibres transmit the electrical impulses from the AV node to the apex of the heart, where the wave of ventricular contraction begins, sweeping upwards and outwards pumping blood into the pulmonary trunk and the aorta.

Question 32

What is ischemic heart disease?

Answer 32

It's the term given to heart problems caused by narrowed heart arteries. When arteries are narrowed, less blood and oxygen reaches the heart muscle. This is also called coronary artery disease and coronary heart disease.

Question 33

What is angina?

Answer 33

Angina is a type of chest pain caused by reduced blood flow to the heart. Angina is a symptom of coronary artery disease. Angina, also called angina pectoris, is often described as squeezing, pressure, heaviness, tightness or pain in your chest.

Question 34

Myocardial infarction (MI)?

Answer 34

Myocardial infarction (MI) refers to tissue death (infarction) of the heart muscle (myocardium) caused by ischaemia.

Question 35

Congestive heart failure (CHF)

Answer 35

Heart failure is where the heart is unable to pump blood around the body properly and needs treatment to help it work.

Question 36

Atheroma

Answer 36

Atheroma is the medical term for the buildup of materials that adhere to arteries. Among others, these include: fat. cholesterol.

Question 37

Sclerosis

Answer 37

Sclerosis is the stiffening of a tissue or anatomical feature, usually caused by a replacement of the normal organ-specific tissue with connective tissue.

Question 38

A thrombus

Answer 38

A thrombus is a blood clot that forms in a vessel and remains there. An embolism is a clot that travels from the site where it formed to another location in the body

Question 39

Aneurysm

Answer 39

An aneurysm is a bulge in a blood vessel caused by a weakness in the blood vessel wall, usually where it branches. As blood passes through the weakened blood vessel, the blood pressure causes a small area to bulge outwards like a balloon.

Question 40

Embolism

Answer 40

What is an embolism? A blood clot that forms in a blood vessel in one area of the body, breaks off, and travels to another area of the body in the blood is called an embolus. An embolus can lodge itself in a blood vessel. This can block the blood supply to a particular organ.

Question 41

DVT

Answer 41

Deep vein thrombosis (DVT) is a medical condition that occurs when a blood clot forms in a deep vein. These clots usually develop in the lower leg, thigh, or pelvis, but they can also occur in the arm.

Question 42

Varicose vein

Answer 42

Varicose veins are caused by increased blood pressure in the veins. Varicose veins happen in the veins near the surface of the skin (superficial). The blood moves towards the heart by one-way valves in the veins. When the valves become weakened or damaged, blood can collect in the veins.