B.7 Chronic Heart failure Flashcards
What is heart failure ?
Failure of the heart as a pump to meat circulatory needs.
the input of the heart is insufficient for the needs of the body to perform the activity
What can heart failure be due to?
Failure of the heart muscles or failure of the heart vavlves
What can heart failure be precipitated by?
Pregnancy
Anemia
Hyper and hypothyrodism
Fluid retaining drugs:
- Glucocorticoids
- NSAIDs
What happens to the heart after an increase in afterload?
Hypertrophy of the heart
Cardiac enlargement, therefore, increases the work of the heart and lessens the ejection fraction.
The heart becomes less effective
When a heart experiences circulatory failure what happens to the body to compensate?
Neurohormonal adaptation:
sympathetic nervous activation
Renin-anfiotensin-aldosteriine system
Antidiuretic hormone (ADH)
Atrial Natriuretic Peptide (ANP)
What activates the RAAS?
Low NA+
Low BP/volume
Beta-adrenoceptors
What does neurohormonal adaptation lead to?
Increase afterload
Increase circulatory volume (increase preload and afterload)
Increased resistance will lead to impaired renal function, more salt/water retention with further activation of RAAS
A vicious cycle develops which further impairs the pump activity of the heart
Neurohormonal activation leads to myocyte dysfunction
What does left-sided heart failure lead to?
LV impaired (poor output) leads to
- Increase in left atrial/pulmonary venous pressure with pulmonary edema
Makes it very hard to breath
What is oedema?
Accumulation of fluid in tissues
This leads to swelling
What does right-sided heart failure lead to?
Increase pressure in the whole of the venous system
Increase fluid accumulation in ankles due to hydrostatic pressure die to gravity
What is right-sided heart failure often due to?
Lung disease
Pulmonary valvular stenosis
When does biventricular heart failure occur?
When a disease such as IHD has affected both ventricles
What are the signs and symptoms of CHF?
FAtigue, listless Poor exercise tolerance Cold peripheries Low blood pressure Reduced urine flow Weight loss
What are the signs and symptoms of left ventricular failure?
Pulmonary oedema
Dyspnoea
(breathlessness/sensation of drowning)
Wet cough
Orthopnoea- breathlessness on laying down but relieved by sitting up
Inspiratory crepitations (cracking noises)
What are the signs and symptoms of RV failure ?
Raised venous pressure
Increases JVP
Enlarged liver
Oedema- ankles; if lying down raise to thigh/abdomen
