Heart Failure Flashcards
1
Q
general facts
A
- 5.8 million americans
- 670,000 new per year
- 3.5 million hospitalizations per year
- 5 year mortality of 50%
- costs 34.8 billion per year
- prognosis of life is improving and mortality increasing
- longevity, more cases
2
Q
definition
A
- inability of the heart to meet the metabolic needs of the body
- different from cardiac dysfunction with successful adaptation
- when adaptation fails and becomes part of the problem
- clinical diagnosis is a complex of findings
3
Q
causes of heart failure
A
- decreased circulatory supply to the body
- CAD, MI, ischemic cardiomyopathy
- valvular heart disease
- cardiomyopathy - increased circulatory demand from the body
- HTN
- thyrotoxicosis
- anemia
- AV fistula - Heart failure-final common pathway
4
Q
adaptive mechanisms
A
- compensations that maintain pump function in the presence of heart disease or increased demand
1. Frank Starling (short term)
2. Neruo-hormonal (intermediate)- renal
3. Hypertrophy
5
Q
starling
A
- improved ventricular performance when end diastolic volume increases
- normal curve moves up and to the left with increased SNS or exercise
- curve moves down and right with impaired ventricular function
- progressive reaction until you can’t compensate anymore then shock
6
Q
increased plasma NE
A
- increased release from neurohumoral nerve endings
- decreased uptake by neurohumoral nerve endings
- decreased rate of degradation
- eventually leads to B1 receptor exhaustion due to chronic stim and decrease in B1 receptor synthesis
- increase in coronary sinus NE output
- increased PNE associated with decreasing length of survival
7
Q
Neurohormonal sympathetic stim
A
- redistribution of CO
- maintains flow to brain and heart
- at expense of skin, skeletal muscle and kidneys
- much less to skeletal muscle
- total output goes down with severe CHF
8
Q
renal mechanisms
A
- stimulated by dec GFR, dec RBF, inc aldosterone
- response is increases Na and water retention, increased plasma volume, increased venous return, increased venous pressure
9
Q
beta receptor density
A
- decreases in patients with failing hearts because they are over stimulated
- only B1
- response to IV epi goes down in failing patients
10
Q
renin-angiotensin
A
- activated by adrenergic stimulation of J-G apparatus and decreased renal blood flow
- angiotensin II has various affects all over the body that lead to increased Na and water retention
- increases thirst
- vasoconstricts
- can lead to myocardial hypertrophy and increased NE, vessel hypertrophy
- increases aldosterone
- increases AVP
11
Q
ANP
A
- counter regulatory
- promotes vasodilation, natriuresus, suppresses RAS
12
Q
brain natriuretic factor
A
- from ventricles
- counter regulatory, actions similar to ANP
13
Q
endothelin
A
-powerful vasoconstrictor
14
Q
IF cytokines
A
-TNF alpha promotes cell hypertrophy and apoptosis
15
Q
in heart failiure
A
- plasma NE increases
- renin increases
- Aldosterone increases
- ANP increase
- Endothelin increases
