3.B-Heart Failure Basics Flashcards
True or false: heart failure is a condition that relies heavily on antihypertensives with blood pressure reduction being the goal
false
antihypertensives are heavily relied on but blood pressure reduction is NOT the goal
What is the fundamental problem with heart failure?
reduced cardiac output
What will happen in the kidney in someone with heart failure?
the reduced CO means less blood pumped to the kidney thus glomerular pressure will decrease which results in:
-renin release
-RAAS activation but RAAS wont improve GFR
-RAAS will be active 24/7
If the CO of the left ventricle decreases but the amount of blood returned to the heart is not changed, what happens to the pressure in the vena cava?
increases
it will expand due to the backup of blood flow
What is preload?
the degree to which the ventricle(s) is stretched before it contracts
also called filling pressure
What is the preload like in someone with heart failure?
preload is high
due to the high volume of blood being returned but not cleared
not able to pump all the blood returning from the venous system
blood backs up and increases preload
Why is high preload exacerbated by RAAS activation?
RAAS activation by the kidney is putting more fluid in the system but the left ventricle is doing a poor job of ejecting blood therefore GFR is not fixed and RAAS continues to be activated
What is Starlings Law?
the force of contraction is proportional to the initial length of the cardiac muscle fiber
-increased preload (stretch)=increased work of the heart
(MVO2)
-HF lacks this stretch and work
What happens to the body (not in terms of symptoms) from heart failure?
high adrenaline and RAAS due to baroreceptors
high preload
reduced blood flow to the brain
reduced blood flow to muscles
What are the primary symptoms of heart failure?
dyspnea (difficulty breathing)
fatigue
What are the two main types of heart failure?
HFpEF-heart failure with preserved ejection fraction
-diastolic disfunction (relaxation disfunction)
HFrEF-heart failure with reduced ejection fraction
-left ventricular systolic disfunction (contraction disfunction)
What is ejection fraction?
the % of blood in the left ventricle that is pumped out during contraction
What is normal ejection fraction?
50-75%
True or false: in HFpEF the ejection fraction is off but the CO is in normal range
false
ejection fraction is in the normal range but CO is low
What are the most common causes of heart failure?
heart attack (70% of HFrEF cases)
hypertension (the slow way to get heart failure)
Which drugs are used for HFrEF?
volume overload: TZD or loop diuretics and SGLT-2 inhibitors
RAAS activation: entresto or ACEI/ARB
MRA
SNS activation: beta blockers
Why are diuretics used in HFrEF?
reduces the symptoms associated with fluid retention
-volume overload
-high preload
-edema
-pulmonary congestion
-orthopnea
Why are ACEI or ARBs or Entresto used in HFrEF?
reduces ANGII and aldosterone
-vasoconstriction
-cardiac remodeling
-SNS activation
-Na and fluid retention
Why are MRAs used in HFrEF?
benefits of further aldosterone blockade
-reduce cardiac fibrosis and remodeling
-reduce inflammatory trigger
-reduce progression of arterial narrowing
Why are beta blockers used in HFrEF?
beneficial effects of interfering with SNS transmission
-reduced exposure of cardiac cells to NE
-may reverse some remodeling of cardiac tissue
-lower HR–>improves ventricular filling time–>can improve EF
True or false: non-DHP CCBs are safe in heart failure
false
they dont shield the heart against adrenaline
What is heart failure?
a progressive clinical syndrome that can result from changes in cardiac structure or function that impairs the ability of the ventricle to fill with or eject blood
What is the result of RAAS overstimulation due to decreased GFR (induced by heart failure)?
fluid retention
edema
increased vascular volume
What would to a normal healthy heart when there is an increased venous return?
in a healthy heart, an increased venous return is accompanied by an increased cardiac workload
-absent in heart failure
What are the medications used in HFpEF?
ongoing research to identify the best way to manage
What are common challenges associated with heart failure medications?
blood pressure reduction
-drugs used in HFrEF are not for lowering bp
-bp reduction becomes a side effect
renal perfusion
-lower GFR
-K can increase
