22 - cardiovascular disease Flashcards
(47 cards)
what is the leading cause of death in the UK and worldwide?
coronary heart disease.
how many deaths are caused by coronary heart disease in the UK each year?
over 64,000 deaths a year
what is stenosis?
A valve that is stiff and can not open properly.
what is calcific stenosis?
if a valve that is stiff and not able to open properly is caused by a build up of calcification plaques.
how can the aortic valve be stenosed?
sue to a bi-cuspid valve - this is when two of the leaflets are fused together.
what does a valve not shutting properly cause?
may cause the valve to be leaky.
this is known as regurgitation and is more common in the mitral valve.
what are the three layers of the normal arterial wall?
- tunica intima (inner)
- tunica media (middle)
- tunica external (outer)
what does the elasticity of the artery allow?
this elasticity allows a degree of stretching at high blood pressures and recoiling (pulsating) of the vessel wall to push blood along the arteries.
what happens if the artery wall becomes stiff?
this is known as arteriosclerosis.
what is stiffening of arteries due to fatty plaque know as?
atherosclerosis.
how does atherosclerosis occur?
it is caused by fatty deposits in the tunica intima layer (between the endothelium and tunica media) of the vessels which accumulate into calcific plaque.
what happens if there is significant narrowing of the artery?
not enough blood reaches critical tissues. this leads to angina which is characterised by thickness in the chest and pain.
plaque breaking odd and blocking a vessel somewhere.
a completely blocks vessel can lead to ischemia which can progress to a heart attack or stroke (in brain) as tissues are deprived of oxygen. if not treated quickly, this leads to tissue death (necrosis).
thought to be irreversible but can be managed with pharmaceutics and improved healthcare.
what is tissue death due to lack of oxygen know as?
infraction.
what is myocardial infraction?
it leaves the remaining myocardium needing to work harder to compensate for the loss of contracting cardiac muscle cells.
if left untreated more cells die (ischemia cascade).
what happens when myocardium’s are damaged?
damaged myocardium conducts more slowly compared to the SA node. this leads to arrhythmias (i.e. ventricular fibrillation) which can be lethal.
what factors contribute to a heart attack?
- high blood pressure
- high blood cholesterol
- smoking
- obesity
- lack of exercise
- diabetes mellitus
- stress
what are the symptoms of a heart attack?
- tightness in chest
- pain radiating down left arm
- pain can also mimic heartburn
- shortness of breath due to pulmonary oedema
- weakness
- light-headedness
- nausea
what are aneurysms?
when the local arterial pressure exceeds the elasticity of the artery, the walls bulge out resulting in an aneurysm.
if this aneurysm gets too large, it can rupture.
what are the most common places for aneurysms?
the abdominal aorta and the brain (cerebral aneurysm)
what is cardiac arrhythmia?
a normal heart beat is a sinus rhythm. abnormal heartbeats are known as cardiac arrhythmias.
what are the three types of cardiac arrhythmias?
- hearth beating too slow (<60 bpm) = bradycardia
- heart beating too fast (.100 bpm) = tachycardia
- extra heartbeats occurring out of sync = ectopic heartbeat
what is fibrillation?
a type of arrhythmia used to describe an irregular and unsynchronised rate of contraction on the muscle fibres by other areas of the conduction system.
what are some symptoms of fibrillation?
- feelings of a racing heart
- thumping heart - caused by a skipped heartbeat followed contraction
- chest pain
- dizziness and breathlessness.
what is fibrillation caused by?
- most common type: coronary artery disease and myocardial infraction
- heart failure
- hypertension
- valvular heart disease
