How the CVS fails Flashcards
What is the definition of stroke
the rapid loss of brain function due to loss of perfusion to part(s) of the brain
What are the two types of stroke and what are their causes.
Haemorrhagic: cerebral blood vessel rupture
Ischaemic: Cerebral blood vessel blockage
What causes Blood vessels to burst
Stresses: high BP, turbulent flow, low compliance
damage: trauma, atherosclerosis and diabetes.
What is compliance
The change in volume caused by a change in pressure.
Outline some endothelium activities
BV tone: vasodilatation
fluid filtration: blood-brain barrier, kidney (glomerulus), GI secretions
Haemostasis: fibrinolysis
Angiogenesis: the creation of capillaries
What is an acute MI
A region of heart tissue that is dead or dying, usually caused by a blocked coronary artery, reduced the capacity of the heart to pump.
can be fatal.
What is atherosclerosis
A disease process that results in the furring of arteries, results from hyperlipidemia and immune actions.
What is CAD
A disease process resulting in obstruction of the arteries supplying heart tissue,
symptoms include angina and may be asymptomatic
the primary cause is atherosclerosis
Outline sympathetic activity during and MI
The sympathetic NS releases adrenaline and noradrenaline during an acute MI as a response to pain to help compensate during HF, it can lead to increased HR and contractility.
Outline pulmonary oedema
fluid accumulation in the lungs which impairs gas exchange, caused by LHF, symptoms include dyspnoea/ orthopnoea and can lead to hypoxia.
Outline peripheral oedema and ascites
peripheral oedema and ascites are caused by RHF.
PO is the swelling of tissue esp the ankles due to fluid build-up in the body that moves to the ankles due to gravity.
ascites is the build-up of fluid in the peritoneal cavity
What is compensation
Maintaining homeostasis of physiological function despite stressors or malfunctions. In HF to maintain adequate CO, plasma volume and sympathetic activity increase.
What is decompensated HF
A medical emergency, failure of the heart to maintain adequate blood circulation, after a long-standing vascular disease, respiratory stress.
What is cardiac remodelling and what is the treatment?
The growth of cardiac muscle as a response to injury such as MI, hypertension. The result is hypertrophy or dilation, initially, it is compensatory but becomes pathological.
treatment: ACE inhibitors or spironolactone.
What are the two types of ventricular hypertrophy?
Eccentric: dilate due to volume overload.
concentric: thickens due to pressure overload.
Describe the actions of ADH on BP
causes kidneys to absorb more water which increases blood volume and as a result increases bp.
Describe the actions of Aldosterone on BP
causes kidneys to reabsorb more NaCl and thus more water which results in greater blood volume and greater BP.
Outline the RAAS
angiotensinogen produced by the liver is transformed into angiotensin 1 by renin which is secreted by the kidney.
angiotensin 1 is converted into angiotensin 2 by ACE and angiotensin 2 causes aldosterone secretion which increases BP.
Outline the impacts of Ang 2
It causes vasoconstriction and increased fluid retention all which contributes to ventricular hypertrophy and remodelling.
Name 3 classes of diuretic, give examples of each and where they affect the nephron.
Thiazide & thiazide-like, indapamide and blocks reabsorption at the DCT.
Loop, furosemide and blocks reabsorption in the ascending loop.
K+ sparing e.g. spironolactone and blocks reabsorption at the collecting duct.
What is the definition of HF
when the cardiac output is insufficient for meeting the needs of the body.
What is cardiogenic shock and what is the treatment
critically low perfusion due to low CO
treatment: aggressive iv fluid and oxygen with airways maintained.
What are some treatments for chronic heart failure
ACE inhibitors, diuretics and beta-blockers.
