Lecture 05 LV Dysfunction and HF 1 Flashcards
1. Describe the patterns of clinical presentation of LV dysfunction, chronic heart failure and acute heart failure 2. Describe neurohumoral activation in heart failure, with an understanding of the interaction between the renin-angiotensin-aldosterone and sympathetic nervous systems 3. Describe pharmacological interventions in chronic heart failure, with an emphasis on neurohumoral blockage rather than direct stimulation of cardiac contraction in patients with chronic heart failure 4. Understa
Define: Heart Failure
heart failure is a complex clinical syndrome of symptoms and signs that suggest the efficiency of the heart as a pump is impaired, despite normal filling pressures
How many prevalent cases of heart failure are there in the UK?
~ 1 million
Describe the epidemiology of heart failure
cases of heart failure predicted to increase by 50% over the next 25 years
by 2032 23% of the UK population will be aged over 65 and over 3 million aged over 85
Why is research for heart failure treatment so important?
makes 5% all emergency admissions
high cost of treating, mostly due to hospitalisation
currently poor prognosis leading to greater than 30% mortality in the first year and increasing 10% per year after that
A prognosis of heart failure is similar to what cancers?
prostate and colorectal
What is an example of chronic heart failure?
left ventricular systolic dysfunction (LVSD)
What is an example of acute heart failure?
heart failure with preserved ejection fraction (HFPEF)
What type of heart failure is HFPEF?
diastolic
What causes heart failure?
structural or functional abnormalities of the heart
What are the most common risk factors?
smoking, drinking and diabetes (fat build up)
What therapy has been the most/least promising for LVSD?
vasodilator therapy via neurohumoral blockade
not direct LV stimulants
Does LVSD also mean heart failure?
no, but it will if there are problems with diastole or the valves
What are the symptoms of LVSD?
reduced cardiac output
increased filling pressures (backwards pressure)
What do these symptoms present as?
fatigue and exercise intolerance
pulmonary oedema (breathlessness)
congested and prominent jugular veins
ankle oedema
What drug can be used to treat heart failure and hypertension?
diuretics
What are the four classes of diuretics?
thiazides
loop diuretics
potassium-sparing diuretics
aldosterone antagonists
Give examples of thiazides (x3)
bendroflumethiazide
hydrochorothiazide
chlorothalidone
What do Thiazides act on?
act on distal tubule to treat hypertension
Give examples of Loop Diuretics (x2)
furosemide
bumetanide
What do Loop Diuretics act on?
loop of Henle
key for treating heart failure
Give examples of Potassium-sparing Diuretics (x4)
spironolactone
eplerenone
amiloride
triamterene
What is a side effect of Spironolactone? What should you do if this occurs?
has an effect on oestrogen and progesterone causing breast tissue sensitivity in males and females
if occurs switch patient to eplerenone
What does spironolactone and eplerenone act on?
encourage sodium loss through the angiotensin system
What is the advantage of Spironolactone over more traditional Potassium-sparing Diuretics?
cheap
very effective
huge impact on patient survival
What are the more traditional Potassium-sparing Diuretics?
amiloride
triamterene
How do Aldosterone Antagonists work?
block the aldosterone pathway
What are the main adverse effects of Diuretics?
hypovolaemia hypotension hypokalaemia hyponatraemia hypomagnesaemia hypocalcaemia hyperuricaemia and gout
What are the adverse effects of Thiazides?
erectile dysfunction
diabetes
Give an example of vasodilator therapy. How does it work?
hydralazine and isosorbide dinitrate
hydralazine is an arterial dilator
isosorbide dinitrate is a venous dilator buffering blood supply and decreasing venous return
In terms of personalised medicine, what must be taken into consideration when treating with hydralazine and isosorbide dinitrate?
ethnicity
genetic differences mean this treatment has greater impact on Afro-American’s aldosterone pathway
What was the result of the vasodilator therapy study on mortality?
significant reduction in mortality by 36%
Is Prazosin a good vasodilator for LVSD? Why?
no, little difference between placebo and prazosin treatment in terms of mortality
