druggie drugs for heart failure (week 5) Flashcards
name examples of some inotrops and pressors
- dopamine
- dobutamine
- epinephrine
- norepinephrine
inotrope/vasopressor MOA
- beta adrenergic AGONISTS
increase the availability of intracellular calcium and thus increase the force of ventricular contraction (shift the Frank-Starling curve upwards)
increase SV and cardiac output at any end diastolic volume
- alpha adrenergic AGONISTS
increase vasoconstriction in periphery
norepi is more alpha 1
epi is more B1 and B2
overall: increase inotropy, chronotropy and vasoconstriction of periphery
what are inotropes/vasopressors used for
ACUTE CHF
indications for inotrops/vasopressors
very useful in patients with systolic ventricular dysfunction (as opposed to pure systolic failure)
administer thru IV for temporary hemodynamic support, in acutely ill, hospitalized patients
what type of CHF are diuretics used to treat
acute CHF
MOA of diuretics in CHF
promote elimination of sodium and water through the kidney and thus reduce intravascular volume
this means lower venous return, lower preload and thus lower diastolic pressure
goal is to REDUCE END DIASTOLIC PRESSURE WITHOUT AFFECTING SV–> its possible if patients are on “flat” portion of frank-starling curve
indications for diuretic use in heart failure
indicated when there is evidence of pulmonary congestion (rales) or peripheral interstitial edema
why do you have to be extra careful with diuretics in patients with LV diastolic dysfunction?
avoid over-diuresis because patients with this condition require a higher diastolic filling pressure to function
name some diuretics
loop: furosemide, torsemide, bumetanide
thiazide: hydrochlorothiazide, metolazone
name a nitrate used in CHF
nitroglycerin
what type of CHF is nitro used for
acute AND chronic
nitrate MOA in CHF
vasodilate primarily venous–> increased venous capacitance–> decrease venous return to heart–> decrease LV preload–> decrease LV diastolic pressure–> pulmonary hydrostatic pressure falls and pulmonary congestion improved
examples of ACEi
captopril
ramipril
enalapril
fosinopril
what type of CHF do you treat with ACEi
CHRONIC
why would you use ACEi to treat CHF?
because inhibits RAAS and Angiotensin II which is a vasoconstrictor
results in vasodilation of veins and arteries
also facilitates Na+ excretion and thus lower intravascular volume
increased bradykinin levels lead to vasodilation
effect is to decrease pulmonary congestion, limit maladaptive ventricular remodeling and decrease heart failure symptoms and need for hospitalization
improved survival in those with chronic CHF
name some ARBs
isosartan
candesartan
irbesartan
what type of CHF are ARBs used for
chronic
what type of CHF are beta blockers used for
chronic
CONTRAINDICATED IN ACUTE CHF
why are beta blockers used in CHF
because despite their antagonism of the beta receptors they improve CO, reduce hemodynamic deterioration and increase survival
how is acute CHF managed
diuretic (lasix–loop diuretic)
natriuretic peptides
inotropes/pressors
nitroglycerin
NOT beta blockers or ACEi
no nitro or diuretics if hypotensive
how is chronic CHF managed
*ACEi–reduce preload and afterload
*beta blockers–reduce cardiac workload
ARBs–reduce preload and afterload
*diuretic
*digoxin–inotrope and negative chronotrope and antiarrhythmic
exercise training
salt/fluid restriction
weight management
dopamine
inotrope/vasopressor
nitroglycerin
nitrates
losartan
ARB
