[L3 Anatomy and Physiology] Section 1: The heart and circulatory system Flashcards
What is the myocardium?
The Cardiac muscle, which is the predominant tissue of the heart.
How does the heart prevent unwanted backflow of blood into the chambers of the heart?
Using a number of valves
The valves open and close in response to what?
Changes in pressure as the heart contracts and relaxes
What are the main valves of the heart?
Atrioventricular (AV) valves and the Semilunar (SL) valves
Where is the Atrioventricular (AV) valve located
The AV valves are located between the atria and the ventricles and prevent the back-flow of blood from the ventricles into the atria.
Where is the Semilunar (SL) valve located
The SL valves are located at the base of the arteries leaving the heart (aorta and pulmonary artery).
What is Coronary Circulation?
The circulation of blood to the heart
The heart, like any other tissue, requires a
constant supply of what?
Oygen and Nutrients
The right coronary artery supplies blood to which area of the heart?
Myocardium of the right ventricle
The left coronary artery supplies blood to which area of the heart?
Myocardium of the left ventricle and posterior of heart.
Blood supply to the tissues can be maintained despite vessels becoming damaged (due to heart desease), because of what?
Most regions of the heart are served by more than one branch of coronary arteries.
What is ischaemia?
Reduction in blood flow
What is Myocardial ischaemia and what can it cause?
Reduction in blood flow to the heart through coronary circulation and can result in a myocardial infarction (or a heart attack)
Most heart problems can be attributed to poor coronary circulation as a result of?
Blood clots, fatty plaques building up in the coronary arteries or spasms in the smooth muscle of their walls
Vascular disease is?
The narrowing of the blood vessels
Vascular disease is one of the main causes of death in the developed world and it is caused by?
Inflammation in blood vessels, accumulation of mineral, protein and fat deposits, which create a build-up of plaques on vessel walls.
What is atherosclerosis?
Hardening of the arteries
Describe what happends when an atery becomes inflamed or damaged.
Plaque forms on the artery walls (as the body attempts to repair the artery using cholesterol, protein and mineral deposits).
(As the plaque build ups) The artery becomes thicker, harder and less elastic.
The artery is then narrower and less able to stretch in response to blood flowing through it (so blood flow/oxygen to tissues is reduced).
Coronary atherosclerosis can be associated with what type of pain?
Chest pain on exertion that settles with rest
Blood pressure is an expression of arterial blood flow and what?
The peripheral resistance the blood encounters as
it flows round the body
What is total peripheral resistance and what happens to blood pressure when it increases?
The resistance the blood vessels offer to blood flow; the greater the resistance, the higher the blood pressure
Express Blood Pressure as a formula.
BLOOD PRESSURE = CARDIAC OUTPUT X TOTAL PERIPHERAL RESISTANCE
140-159/90-99 mmHg is classified as?
Stage 1 Hypertension
130-139/85-89 mmHg is classified as?
High normal - Pre-hypertension
What is the most common type of stroke?
Ischaemic stroke
What is a thrombosis?
An obstruction of a blood vessel leading to the brain by a localised blood clot
What is an embolism?
An obstruction due to an embolus – a detached blood clot – from elsewhere in the body
What is a haemorrhagic stroke?
An intracranial bleed linked to an aneurysm (localized, blood-filled, balloon-like bulge in the wall of a weakened blood vessel).
What is the short-term effect of exercise on systolic blood pressure?
A linear increase in systolic blood pressure (SBP)
with increasing levels of exertion.
What is the short-term effect of exercise on diastolic blood pressure?
A slight decrease during exertion due to vasodilation, or it will remain unchanged.
Individuals with hypertension may experience what effect on diastolic blood pressure, and why?
A rise in diastolic blood pressure as a result of an impaired vasodilatory response.
What effect does heavy weight training and isometric exercise have on systolic and diastolic blood pressure?
Significantly increases both systolic and diastolic blood pressure.
Why is it important for an individual not to hold
their breath when performing eavy weight training and isometric exercise?
To avoid the Valsalva effect -which can
drastically increase blood pressure and heighten the risk of a cardiovascular event such as a heart attack or stroke
What are some long-term benefits of aerobic/endurance training on the cardiovasuloar system:
- A greater stroke volume, i.e. more blood pumped per beat.
- A lower relative exercise heart rate, which allows for greater performance potential.
- Stronger, more elastic arteries.
- Lower levels of bad cholesterol (LDL) and higher levels of good cholesterol (HDL).
- An improved blood supply to the body’s tissues.
- Higher levels of haemoglobin in the blood, which increases its oxygencarrying capacity.
- Improved aerobic capacity (VO2 max).
- Lower blood pressure in the long term.
