Cardiovascular Sustem Flashcards
Where is the heart located?
The head lies beneath the breast bone in a cavity called the mediastinum
What are the three layers of the heart
Endocardium - inner lining that lines the chambers and the heart valves
Myocardium- heart muscle - contains mitochondria which provides the muscle cells with energy
Pericardium - outer surface - protects and prevents overfilling of the heart
What are the four heart valves?
Tricuspid valve
Mitral valve
Aortic valve
Pulmonary valve
Definition of systole
The peak pressure produced when the heart contracts
Definition of diastole
The lowest pressure when the heart relaxes
Definition of heart rate
The number of times the heart beats per minute
number of ventricular systole as in a minute
Definition of stroke volume
The volume of which blood is ejected from the heart each time the heart beats
Definition of cardiac output
The amount of blood pumped out of the heart in one minute
What is the function of the cardiovascular system?
To transport nutrients & gases around the body via oxygenated blood
Describe the coronary blood flow
The heart needs it’s own blood supply
Supplied by the coronary arteries which branch off the aorta
They carry blood to the heart muscle to give a continuous blood supply
What are the four chambers of the heart
Right aorta
Right ventricle
Left aorta
Left ventricle
Aorta- upper chambers, thin walls, pumps blood into ventricles
Ventricles- lower chambers, thick walled. Right ventricle pumps blood to lungs. Left ventricle pumps blood to rest of body via aorta
What is the order in which blood flows through the heart
Inferior/ superior vena cava
Right atrium
Right ventricle
Pulmonary artery
Lungs
Pulmonary vein
Left atrium
Left ventricle
Aorta
What is a heart valve
They permit blood flow in one direction and prevent back flow of blood
Where is the tricuspid valve found?
Between the right atrium and the right ventricle
What is the pulmonary valve found?
Between the right ventricle and the and pulmonary artery
Prevent blood from flowing back into the right ventricle
Where is the mitral valve found?
Between the left atrium and the left ventricle
Where is the aortic valve found?
Between the left ventricle and the aorta.
Prevents blood from flowing back into the left ventricle
What are the five types of blood vessels?
Arteries - transport oxygenates blood from the heart the body
Arterioles- connect arteries and capillaries
Veins- transport deoxygenated blood from the body to the heart
Venules- connect capillaries and veins
Capillaries- allow gas exchange, transfer nutrients and removes waste
What are the three structures to blood vessels
Tunica externa- the outer layer made of collagen. Provides structural support to blood vessels
Tunica media- middle layer made of smooth muscle and elastic. Can initiate vasoconstriction or vasodilation
Tunica interna- smooth, outer layer of cells called the epithelium. In direct contact with blood
What is the lumen?
A structure inside blood vessels that allows blood to flow through.
It can either constrict or expand to control the amount of blood flowing through
What is vasoconstriction?
When the lumen inside the blood vessels constricts to reduce the volume of blood flow.
This causes higher blood pressure due to their being a higher pressure of blood flowing through the vessels
What is vasodilation?
Is when the lumen inside blood vessels widen to allow a higher volume of blood to flow through.
This occurs to enhance blood flow to areas of the body that are lacking oxygen
Changed to the cardiovascular system during pregnancy?
Cardiac output - increases
30-40% higher in first trimester
up to 40%-50% by the third trimester
Stroke volume- Increases by 30%
Heart rate- increases by 10-15 bpm
High blood volume due to an increase in left ventricular dimension
Why does the cardiovascular system change during pregnancy?
To meet the increased metabolic demands of the mother & fetus
