21-31 - Heart Failure Flashcards
bowditch phenomenon
icnreases in heart rate cause an increase in contractility ( saves CO - filling time issues)
frank-starling mechanism
increases in preload increase the contractility
Anrep =
if you increase the afterload, contractility will increase
in the excited state ____- preload is needed to increase SV because of changes in contractility
smaller preload to get same increase in SV
main cause CHF
cardiac remodeling
high risk for developing HF
stage A
- HTN
- CAD
- DM
- family hx
asymptomatic HF
stage B
- previous MI
- LV systolic dysfunction
- asymptomatic valvular disease
symptomatic HF
stage C
- known structural heart disease
- SOB and fatigue
- reduced exercise tolerance
refractory end-stage HF
stage D
- marked symptoms at rest despite maximal medical therapy
drug at all stages of HF
ACEi or ARB
drug starting at stage B of HF
b- blocker
added to ACEi or ARB
drug starting at stage C of HF
lots, notably Diuretics and Digoxin added to ACEi or ARB
symptomatic HF, african-american race
hydralazine and nitrates and ACEi and B blocker
symptomatic HF with afib
digoxin
ACEi
b-blocker
drug that is bridge to transplantation or end of life
positive ionotropes
4 practical approaches to increase intrinsic myocardial contractility
- increase cytosolic Ca2+
- increase myocardial cAMP
- agonism of B1 receptors
- increase B1 receptor density
what drugs increase B1 receptor density?
b1 adrenergic antagonists
example b adrenergic agonists
dobutamin, epinepthrin, NE, dopamine
what drugs increase myocardial cAMP
phosphodiesterase inhibitors
amrinone, milrinone
what drugs increase cytosolic Ca2+
cardiac glycosides
digoxin
MOA digoxin
blocks Na/K ATPase to increase intracellular sodium and extracellular Ca2+
positive ionotropic effects of digoxin
decrease EDV and ESV
decrease systemic and pulmonary venous pressure
decrease SANS
digoxin has a ____ vagal effect
direct –> increases vagal tone
how does digoxin affect coronary flow
increases it (by decrease hypertrophy)
