Congestive heart failure Flashcards
What is systolic heart failure?
Failure of the heart to pump sufficient blood. It is when the ejection fraction is 40% or below.
How does one calculate ejection fraction?
What is a normal %?
volume of blood ejected (SV)/ total volume of blood in heart
normal % is 50-80%
What is diastolic heart failure?
What is the ejection fraction in HF?
Failure of heart to FILL enough (reduced preload).
The EF is still normal because the total volume has reduced.
What is the frank-starling law?
States that SV is increased by a greater EDV - end diastolic volume.
Hence why increased venous return will increase SV.
Causes of Systolic Left sided HF?
The following cause Systolic left sided HF;
- Ischaemic Heart disease - bcos insufficient blood flow to myocardium can cause infarct
- Long standing HTN - increases afterload, increasing myocardium work = hypertrophy = increased oxygen demand = weaker contraction.
- Dilated cardiomyopathy - myocardium because thinner = weak
Causes of Diastolic Left sided HF?
- Restrictive cardiomyopathy
- Hypertrophic cardiomyopathy
- Long standing HTN
- Aortic stenosis
How does left sided heart failure cause pulmonary oedema?
Blood in left side begins to back up into the lungs through the pulmonary vein.
this increases pressure in pulmonary arteries leading to leaving vessels into the interstitium of the lung.
How does left sided HF cause right sided HF?
through increasing pulmonary BP, thus increasing afterload for the righr ventricle = more work
What is cor pulmonale?
abnormal enlargement of the right side of the heart as a result of disease of the lungs or the pulmonary blood vessels.
Causes of right sided HF?
- Cor pulmonale; some lung disease can cause pulmonary vessel constriction - increasing pulmonary pressure hence afterload
Right sided heart failure shows what sign?
JVP distension/elevation
due to blood backing up in systemic circulation
How can right sided heart failure cause cardiac cirrhosis and livr failure?
back up of blood in liver and spleen then prolonged congestion.
fluid can then move into the peritoneal space from this place = ascites
the same back up of blood from the right side = pitting oedema
Difference between CHF and HF?
CHF and HF are used interchangeably but chf is a stage of hf when fluid builds up around the heart and causes it to pump inefficiently.
congential causes of ccf in children?
CCF in children occurs as a result of various congenital abnormalities as well as rheumatic fever. Congenital causes include aortic stenosis, PDA and Eisenmenger’s syndrome.
what would a cxr show for ccf?
other invx that shoudl be done?
CXR may reveal pulmonary vascular redistribution to the upper zones, Kerley B lines, an increased CTR (cardiomegaly) and pleural effusion.
For all patients, initial investigations should include ECG, CXR, TTE and bloods including BNP levels.
