Heart Failure Flashcards
What are the symptoms of heart failure?
Breathlessness, exercise intolerance, fatigue, swelling in the extremities
what is acute Heart Failure the result of?
Sudden circulatory collapse - sudden drop in CO during AMI
what is systolic dysfunction and diatolic dysfunction and which is most common?
Systolic dysfunction = inability of the heart to contract and eject blood - THIS IS THE MOST COMMON
Diastolic dysfunction = lack of compliance to filling e.g. left ventricle thining or thickening = isn’t able to fully relax
Which is most common, left or right sided HF?
Left is most common and the cause of right sided usually
What is the difference between compensated and decompensated HF?
Compensated = managed and controlled with pharmacological help
Decompensated = having several episodes, not managed - will lead to death
Symptoms =worsening breathlessness, coucg with frothy bloody sputum, dizziness, fatigue, coldness NEED HOSPITAL ADMISSION
What compensatory measure is seen in HF patients when trying to meet oxygen demands?
We see an increase in ventricular end diastolic volume = increase in Preload. The more the ventricle is fills, the more it will stretch (like an elastic band) so it will contract with more force to try and reach desired stroke volume. This mechanism will work at rest but will never be able to reach demands at exertion.
What happens during cardiogenic shock?
Blood volume drops e.g. artery has been cut so will never meet hearts needs without pharmacological help to increase contractility = fatal
What are the symptoms at different stages of HF?
- ) asymptomatic but see very early signs of ventricular dysfunction
- ) Breathlessness and fatigue during moderate exercise
- )Breathlessness and fatigue during mild exercise
- ) Symptoms even at rest
HF is usually caused by some form of cardiomyopathy (disease of the myocardium is associated with cardiac dysfunction). What are the main causes?
Inherited:
1.) Congenital hypertrophic cariomyopathy (thickening of ventricles)
3.)Arrhythmic RV Cardiomyopathy (fatty deposits between muscle fibres of the heart = inefficient contractility)
Aquired:
1.) Pressure overload = increased afterload (due to HT - systemic/pulmonary, aortic/pulmonary valve stenosis)
2.) Ischaemic cardiomyopathy e.g. MI, coronary artery disease
3.) Valvular disease (structural damage due to HT or valve stenosis)
4.) Infection/Inflammation myocarditis - can be due to bacteria, viruses, alcohol or chemotherapy
How does HR progression lead to decrease in cardiac function
1.) reduced myocyte contractility = ventricles start to fail
2.) This leads to less CO
3.) this leads to less tissue pefusion as the main organs are prioritised
4.) The body compensated by trying to increase blood volume by retaining water = oedema
5.) Get reduced venous return = less is pumped out from left side to body = less is returned to the right side via the lungs.
BREATHLESSNESS, FATIGUE, OEDEMA
What are the symptoms of reduced cardiac output?
Fatigue, low tolerance to extertion
What are the symptoms of reduced skeletal muscle blood?
Blood is diverted to the major organs causing muscle weakness, fatigue, low tolerance to exertion.
Eventually will see muscle wasting and weigh loss (bc blood not being perfused to gut)
What are the symptoms of LV failure?
Pulmonary oedema = blood isn’t being pumbed into circulation = backlog into lungs = breathlessness, paroxymal nocturnal dyspnoea (fluid moving in lungs in the night = panick)
What are the symptoms of RV failure?
Increase in venous pressure, blood can’t be returned to the lungs to be oxygenated = backlog - will see swelling in the jugular vein that brings blood back down from the brain, will also get hepatic congestion (backlog in abdomen) and peripheral oedema (swelling in arms and legs)
What are baroreceptors part in the neurohormonal axis?
Following a heamorhage there will be a decrease in the firing of the baroreceptors. The medulla senses this and stimulates the SNS to release noradrenaline to act on the beta receptors in the heart and tha alpha receptor in the vasculature. Nad causes an increase in heart rate, peripheral vasoconstricion and contractility (SV) all of which lead to an increase in CO.
