LV heart dysfunction Flashcards
What is chronic heart failure?
NICE- Complex clinical syndrome of symptoms and signs that suggest the efficacy of the heart as a pump is impaired
What is early HF
Filling start to increase so contraction increase and have the same Cardiac output
Fact about the epidemiology of HF
- 1 million cases
- expected 50% increase in next 25 years
- rise exponentially with age
Population age by 2032? and affects on NHS?
- 16 million in UK will be older than 65
- 3 million older than 85
- 5% of emergency budget will be on chronic heart failure
- 2% of NHS budget
- poor prognosis only 30% mortality rate within 1 year
5year survival curves with a first time diagnosis of HF compared to common cancers
For both men and women HF lies in the same survival rates as cancer prognosis
- breast cancer higher survival
- lung lower
Roughly 60% survival
What is LVHD and HFPEF?
Left ventricular heart dysfunction
Heart failure with a preserved ejected fraction (diastolic failure)= the % of the volume of blood ejected from the left ventricle with each heartbeat divided by the volume of blood when the left ventricle is maximally filled - is normal
5 facts about heart failure
What is it? what causes it? effects? phgarmacology?
- HF is a clinical syndrome with signs and symptoms that suggests the efficacy of the pump is impaired
- It is caused by structural or functional abnormalities of the heart
- most common cause is coronary artery disease
- causes morbity, mortality, hospital admissions and substantial cost
- Evidence for pharmacology is in chronic heart failure due to LVSD
- Main benefit is with vasodilator therapy via neurohumoral blockade (RAAS-SNS) and not from direct LV stimulants
Western countries affect
Increase coronary artery disease- smoking, drinking, diet, hypertension etc block the arteries and
- common cause of heart attacks
- most trials done on chronic not acute
Where do drugs act?
On the periphery not the heart itself
LV dysfunction verses heart failure
1. reduced cardiac output
Forward flow
- output impaired and filling pressures are increased
- reduced flow to muscles and lungs
- exercise intolerance and fatigue
LV dysfunction verses heart failure
2. Increased filling pressures
Backward flow
- left arterial pressure up= pulmonary pressure up
- pulmonary edema= excess fluid in the lungs. This fluid collects in the numerous air sacs in the lungs, making it difficult to breathe.
- cause by a rise in the left arterial pressure, backward pressure
- Symptoms = wake up in the middle of the night breathless as fluid has flown back into the lungs after lying down, reverse this by sitting up
- right side= fixed conjunction on jugular vein
What happens if the pressure is increased in the venous system?
causes fluid to leak out, aggrevated by gravity ( ankle swelling when stood up)
Go to bed and redistributed in sleep
seen by pressing on leg and leaving a thumb print
Marked fluid edema= get fluid in abdominal cavity
Frank starling law
Graph of LVEDP v Cardiac output (stroke volume)
-Line to high then you have a higher cardiac output at lower LVEDP= pulmonary congestion
- Line below horizontal the
A law that states that the energy liberated with each cardiac contraction is a function of the length of the muscle fibers in the ventricular wall; as preload ↑, so does end-diastolic pressure, which ↑ force of ventricular contraction
Frank starling graph- horizontal and vertical line explanations
- Above vertical line=lower cardiac output at higher LVEDP= pulmonary congestion
- Line below horizontal= below volume so you have a problem= hypotension
What should you add if in pulmonary congestion?
- diuretics
- vasodilators
moves right to left on the graph lowering the LVEDP`
diuretics clinical indications and classes
Indications= HF and hypertension Classes 1. Thiazides and related drugs (distal tubule) 2. Loop diuretics (loop of henle) 3, potassium- sparing diuretics 4. aldosterone antagonists
Thiazide diuretics
Weak more in HF than hypertension - Bendroflumethiazide - hydrochlorothiazide - chlorthalidone
Loop diuretics
Could get hold of easily
pass lots of urine
- Furosemide
- Bumetanide
Potassium sparring diuretics
Not common
- Spironolactone
- Eplerenone
- Amiloride
- Triamterene
Aldosterone antagonists
Important as help block renal aldosterone