Part 25: Heart Failure Flashcards
at the most fundamental level, what causes heart failure?
progressive damage to the heart that results in reduced cardiac output
reduced CO that is seen in heart failure can present as ____
weakness, fatigue
why does reduced CO in heart failure present as weakness and fatigue?
the body is getting less oxygenated blood to the tissues
the complexity of heart failure comes from what happens when the body tries to ____
compensate and correct for the decreased CO
define cardiac output (CO)
amount of blood pumped per heart beat (stroke volume) x # of heart beats per minute (HR)
to compensate for decreased CO, the ____ nervous system is activated
sympathetic
how does sypathetic activation act to compensate for the decreased CO of heart failure?
NT stimulates B1 receptors in the heart, causing increased heart rate and contractility and increasing renin secretion to increase water retention
why cant we rely solely on our endogenous compensatory mechanisms for treatment of heart failure?
can only be used short term, for example during exercise and heart failure needs chronic attention. If the compensatory mechanisms tried to do this alone, it would lead to damage (remodelling) and the fluid retention may cause edema and difficulty breathing
what are the 3 primary management strategies for managing heart failure?
- reduce symptoms
- decrease progressive damage and remodelling of the heart
- if cardiac output is significantly impaired, adding agents to increase CO
what are the main underlying causes of heart failure?
hypertension and coronary artery disease
in what part of the heart is heart failure most common and why?
the left ventricle bc it does the most work moving blood out into circulation
what is congestive heart failure?
umbrella term for any type of heart failure that has a fluid or congestion component
what does the “congestive” part of congestive heart failure mean?
refers to the accumulation of fluid and edema caused by the failing heart
left sided heart failure means
left ventricular failure to fill and pump blood into circulation
left sided hart failure may cause accumulation of fluid in the ____, which is called ____ and is due to ____
lungs; pulmonary edema; blood backing up i the lungs
right sided heart failure means
right ventricular failure to fill and pump blood to the lungs
right sided HF may cause fluid accumulation in the ___, called ___, due to ___
peripheries; peripheral edema; blood backing up into the veins
t/f failure of one ventricle will often progress to the failure of both
t
is the pumping action of the heart is reduced, this is called ___ heart failure
systolic
the capacity of the heart to pump blood out of the ventricles is measured by the ____ (the % of the blood pushed out of the chamber during contraction)
ejiection fraction
normally, ____% of the blood in the ventricle is pushed out during systole
50-70%
in systolic failure, the contraction of the ventricles pushes ___(more/less) blood out of the chamber, leaving ____ (more/less) behind
less; more
in systolic failure, the ejection fraction / proportion of blood pumped out with each contraction is ____ (increased/decreased)
decreased
a diagnosis of HF is usually made when ejection fraction falls below ___%, but patients in the ____% range can be considered borderline and may experience symptoms of HF with exertion
40; 40-50
systolic HF is more commonly called ___
HF-rEF: heart failure with reduced ejection fraction
____ HF occurs when stiffening of the ventricular walls prevents the chambers from filling to their normal capacity
diastolic
in what type of HF is there less blood in the chamber before contraction, so less blood is pumped to circulation (reduced CO)
diastolic HF
is the EF always reduced in diastolic HF?
no
what is the other name for diastolic HF?
HF pEF: HF with preserved ejection fraction
HF pEF can occur bc despite the volume being reduced, the ____ remains within the normal range
proportion
in HF pEF, why is increasing the contractility of the heart is less likely to improve CO?
the contracting of the heart isnt as much of an issue in this type of HF
in HF pef, reduced ____impairs the filling of the ventricles
stretch of the cardiac muscle
the _____ uses a roman numeral system to characterize HF from class I-IV
New York Heart Association