heart failure Flashcards
What is forward failure?
reduced CO
What is backward failure?
elevated A/V filling pressures
HF-REF
HF with reduced ejection fraction
LVEF < 40%
inability of heart to contract effectively
HF-PEF
HF with preserved ejection fraction
normal LV ejection fraction
LVEF > 50%
inability of heart to relax effectively
What is acute HF?
- rapid onset of symptoms
- sudden decline in cardiac function (hrs/days)
- life threatening
- new or as a result of chronic HF
- decompensated failure
What is chronic HF?
- slow onset of symptoms (months/yrs)
- activation of adaptive responses to maintain organ perfusion in long term
- compensated failure
What are causative features of HF?
- intrinsic myocardial damage
- pressure overload
- volume overload
- inadequate filling
HF-REF pathophysiology mechanisms? (3)
- cardiorenal model
- cardio-circulatory model
- neurohormonal model
What happens in the neurohormonal model?
- drop in CO and fall in BP
- reflex activation of several neurohormonal pathways
- initially are beneficial
- eventually become harmful
What are the beneficial effects of the neurohormonal method?
maintain BP
maintain CO
maintain organ perfusion
What are the harmful effects of the neurohormonal pathway?
progressive decreased cardiac function
progressive decreased CO
systemic/pulmonary congestion
How does the neurohormonal system effect the sympathetic nervous system?
- increase in catecholamines
- inc contractility and HR
- inc systemic/pulmonary vasoconstriction
- inc renin from kidneys (RAAS)
Neurohormonal system on RAAS
inc angiotensin II
inc aldosterone release
-> both toxic to heart, promote remodeling
neurohormonal system and ADH
increases ADH release
which increases water retention and vasoconstriction
What natriuretic peptides are released?
ANP and BNP
What are the active and inactive versions of BNP?
active - BNP
inactive - NT-pro BNP
What are the 2 types of symptoms of HF?
- hypoperfusion - reduced CO
2. congestive - impeded venous return
What are the treatment goals for drug treatment of CHF?
- to improve CO
- reduce atrial/ventricular filling pressures
- reverse/stop remodeling
What does myocardial stimulation do and what is used?
increases myocardial contractility
inotropic agents
What does reducing cardiac workload do and what is used?
reduces afterload/preload
with diuretics, vasodilators
What does arresting/reversing remodeling do and what is used?
inhibits chronic neurohormonal activation
with ACEIs, beta, ARBs, ARNIs, aldosterone antagonists
5 types of drugs in the neurohormonal blockade
- ACEIs
- beta blockers
- ARBs
- aldosterone receptor antagonist
- ARNIs
What do ANP and BNP do?
- counteract the effects of the neurohormonal system
- cause vasodilation, diuresis
- decrease: cardiac stress, remodeling, aldosterone production
Where is ANP released from?
atrial cells
