L9 by uni - heart failure Flashcards
what is heart failure
- when the heart cant supply enoigh blood to the organs so the O3 delivery is decerased
groups of heart failure based on ejection fraction (HR EF)
- preserved EF - HFpEH
- mid range - HFmEF
reduced - HFrEF
other indicators that the patient is suffering from the heart failure
- elevated level of natruretic peptides like ANP, BNP
- structure of the heart chnages like hypertrpoyhy
- diastolic dusfunction
3 main causes of heart failure
pressure overload, vol over load (blood flowing back in), contractile dysfunction
how does the pressure overload lead to hypertrophy
- the ventricular pressure increases si that increases the heart wall stress
- the wall thickens to normalise the wall stress
- the radius of the heart increases while maintaining that thickness of the wall and the pressure
- the heart enlarges
how does Vol overload lead to hypertrophy
- the blood flows back in due to valves not working
- this increases the vol of blood in the heart and also increase the radius of the heart
- the wall thickens so the heart enlarges
formaula for laplace law
pressure = 2 x stress x width
/ radius
compensatory conseq of neurohormonal changes due to heart failure
- Heart failure> BP falls > baroreceptor reflex
- leads to vasocon and increases contractility and HR > increases BP
compensatory conseq of renal changes due to heart failure
- renal artery vasocon
- increased renin, angio 1 and 2 to increase Na conc
- increase CVP and EDP
what happens to the force frew relationship during heart failure
freq increase and the force decreases
-usuallu proportional
what can change the strcuture of the heart during HF
-
what is increased int he pulm ciric regarding the capillary filteration
the hydrostatic pressure is increases so there is a accuml of fluid in the lungds
- can lead to pleural effusion and pulm odema (fluid in the alveolo)
