Anatomy - Cardiovascular system Flashcards
What does the circulatory system consist of
heart, blood vessels and blood
What is the primary function of the circulatory system
transport
What does the cardiovascular system consist of
heart and blood vessels.
What is cardiology
the study of the heart and its disorders
What is angiology
the study of vessels
What is haematology
the study of blood and its disorders
What are all of the functions of the circulatory system
Transport
Protection
Regulation
Transport
The circulatory system transports carbon dioxide and oxygen to and from the lungs, nutrients from digestive system, metabolic waste to kidneys, hormones from glands to target tissues and stem cells.
Protection
The circulatory system is involved in inflammation in response to infection, it includes white blood cells, which destroy pathogens, antibodies and other proteins that help destroy pathogens and is responsible fro blood clotting by using platelets.
Regulation
The circulatory system controls fluid distribution in the body, it helps to buffer pH of the extracellular fluid and it has a role in controlling body temperature by changing skin blood flow.
What are the two circulations
Pulmonary circulation - carries blood to and from the lungs for gas exchange
Systemic circulation - carries blood to and from all parts of the body.
How is circulation implemented
Both circulations are implemented by two pumps at the left and right sides of the heart which are synchronized to beat in unison.
What does each side of the heart do
The right side of the heart receives blood from the systemic circulation and deliver it to the pulmonary circulation and the left side receives blood from the pulmonary circulation and delivers it to the systemic circulation
What is the heart activity over 80 years
3 billions beats
200 million litres pumped
What is the position of the heart
The heart is found in the thoracic cavity, superior to the diaphragm, medial to the lungs and the bulk of the heart lies towards the left of the body.
What is the size of the heart
The heart is about 9cm at the base,
13 cm from base to apex,
and 6 cm anterior to posterior.
(about the size of your fist)
What is the heart contained in
within serous linings
What are the layers of the heart
pericardium (parietal and visceral)
Myocardium
Endocardium
Pericardium
It is the outermost layer of the heart. It has a lot of connective/fibrous tissue. It forms around the pericardial cavity that contains the pericardial fluid, which minimizes friction during beating.
It attaches to the diaphragm inferiorly and to the mediastinal tissue posteriorly.
There is visceral pericardium and parietal pericardium.
Myocardium
It is the cardiac muscle.
Endocardium
It is the inner lining of the heart.
What can we see from the anterior view of the heart
The main chamber observed is the right ventricle, we can see the superior vena cava going into the right auricle and atrium. The pulmonary trunk and left pulmonary artery are also in view. The ascending aorta and the aortic arch. There is aboundant fat coming out of the interventricular sulcus.
The left auricle and ventricle are showing a bit
What can we see from the posterior view of heart
The main chamber in view is now the left ventricle, but a bit of the right ventricle is showing too. And and the posterior interventricular sulcus. About veins, the coronary sinus in the coronary sulcus, the entry of the inferior vena cava, the left atrium and the pulmonary veins coming into the heart, the right and left pulmonary veins and the other side of the aorta.
Inside the heart: right atrium
It has a thin (about four milimiters) but rough wall because of muscular strands called pectinate muscles and then a smooth area called the fossa ovalis which is part of the atrial septum. On the outflow there is the pulmonary trunk and preventing the backflow there is the pulmonary or semilunar valve.
What is the atrial septum
The division between the right atrium and posterior left atrium. Sometimes, with surgery, it is used to cross devices from one side of the heart to the other.
Inside the heart: right atrioventricular valve
it connects the right atrium to the right ventricle, it is also known as tricuspid valve. It is tethered to the myocardium via tendinous chords to columnar papillary muscles. The role of these chords is to prevent the leaflets from going back into the atrium.
What are valves for
They prevent the backflow of blood.
Inside the heart: left atrium
It is much thicker (about 10 milimiters). It has a very smooth wall and it connects to the left ventricle via the atrioventricular, mitral or bicuspid valve.
Inside the heart: left ventricle
It is very thick compared to the left one because it pumps blood to the systemic circulation through the aorta.
Coronary circulation
It is a process in which the heart gets its very own blood supply and drainage.
How much is the coronary flow
250 ml per minute, about 5% of the total cardiac output. This is because the heart is highly metabolic.
About the coronary arteries
The left and right, blood flows during the relaxation phase of the ventricles and provide to the heart, if they become blocked it leads to angina and myocardial infarction.
About the coronary veins
they drain via the coronary sinus into the right atrium
Blood flow through the heart
1 Deoxygenated blood comes in through the inferior and superior vena cana.
2 Then it goes through the tricuspid valve into the right atrium
3 Out through the right semi lunar valve into the pulmonary trunk
4 Pulmonary circulation
5 Then it comes back into the left atrium through the pulmonary veins
6 Then into the left ventricle through the mitral valve
7 and out through the left semilunar valve to the aorta to supply the systemic circulation.
Cardiac muscle
Cardiac muscle is its own type of muscle, separated from the skeletal and smooth muscle. Cardiac cells are called myocytes.
What are myocytes
They are mono-nuclear, relatively thick cells: 10 to 20 micrometers thick and relatively short, 50 to 100 micrometres long. These cells have branches that connect to other myocytes, allowing them to form the myocardium by connecting via intercalated discs.
What are the interdigitating discs
They are interdigitating folds that connect through junctions