Heart Failure Flashcards
Heart failure
Failure of the heart as a pump to meet the circulatory needs
Names of heart failure
Chronic
Congestive heart failure
Congestive cardiac failure
What may heart failure be caused by ?
Failure of the heart muscle or failure of the heart valves
Characteristic of heart failure
Chronic or acute (post MI)
Secondary: IHD (Ischaemic heart disease, hypertension, cardiomyopathies (alcohol viral )
What is heart failure precipitated by?
Pregnancy
Anaemia
Hyper/hypothyroidism
Fluid retaining drugs - glucocorticoids, NSAIDs
How can valvular heart failure be treated?
Easily - surgery
What can chronic heart failure be a consequence of?
MI
What is cardiac function governed by?
Preload, afterload and muscle contractility
What is impaired muscle function usually caused by?
Ischaemic heart disease
How does hypertension contribute to heart failure?
Cardiac enlargement increased work of the heart and lessens ejection fraction
What can cause hypertrophy
Increased afterload - hypertrophy
How does the body try to compensate for circulatory failure?
Neurohormonal adaptation, activation of: Sympathetic nervous system Renin-angiotensin-aldosterone system ADH Atrial natriuretic peptide (ANP)
Which adaptations cause heart failure to be worse?
Activation of
SNS, RAA, ADH
What is ANP
Atrial Natruiretic Peptide
Released by failing atria
Acts on kidney, promotes excretion of Na
Positive effect on circulatory system - circulatory volume increases
What does angiotensin II do?
Increases blood pressure - vasoconstriction and Na retention
Acts on adrenal gland to produce aldosterone
How does RAA make things worse?
Increased resistance - impaired renal function, more salt/water retention with further activation of RAA system
Increased fluid
Increased after load
Further impairs pump activity of the heart
Leads to myocyte dysfunction
Describe left-sided failure
Often secondary to hypertension
LV impaired, leads to increase in left atrial/pulmonary venous pressure with pulmonary oedema
What is pulmonary oedema?
Accumulation of fluid in the tissue of the lungs
Leads to swelling
How does an oedema form?
Increased venous pressure,opposes reabsorption of fluid
Fluid accumulates in the tissues
Describe right-sided heart failure
RV output fails
Often due to lung disease, pulmonary valvular stenosis
Describe biventricular failure
Both chambers
Disease (IHD) has affected both ventricles
LVF leads to pulmonary congestion, may lead to RVF
Signs and symptoms of heart failure
Fatigue, listless Poor exercise tolerance (determines grade) Cold peripheries - vasoconstriction Low blood pressure? Reduced urine flow Weight loss
LV failure signs and symptoms
Pulmonary oedema Dyspnoea – sensation of drowning ‘Cardiac asthma’ Cough - wet Orthopnoea Nocturnal problem? (paxosysmal nocturnal dyspnoea) Inspiratory crepitations
RV failure signs and symptoms
Raised venous pressure
Increased JVP
Enlarged liver
Oedema – ankles; if lying down rises to thighs/abdomen
