L28-heart Failure 2 Flashcards
What are the compensatory responses in heart failure
1-inc sympathetic activity
2-activated RAAS
3-myocardial hypertrophy,dilatation and remodeling
What are the 3 mediators for neurohormonal activation
NE
AgII
Aldosterone
What do the natriuretic peptides do(physiological response)
Vasodilation Dec blood pressure Dec aldosterone levels Naturesis Diuresis Antifibrotic effects
What does the RAAS do(pathophysilogical response)
Activates Angiotensin 2 which acts on the AT1 receptor to: Vasoconstriction Inc blood pressure Inc sympathetic tone Inc aldosterone Inc sodium Fibrosis
What are the 2 main goals in treatment of heart failure
Relieve symptoms
To slow down disease progression,improve survival and dec the long term mortality
What type of drugs can relieve symptoms
▪️Inotropic drugs: 1-sympathomimetics 2-PDE inhibitors 3-cardiac glycosides ▪️Diuretics
What type of drugs can be given to dec long term mortality and slow down disease progression
Beta blockers
ACEI and ARBs
aldosterone antagonist
ARNI
Describe sympathomimetic inotropes
B adrenoreceptor activation which inc myocyte cAMP and inc intracellular Ca
Examples for non selective b1 and b2 drugs
Isoprenaline and isoproterenol
Example of sympathomimetic inotropes(selective) and what does it do
Dobutamine
B1 less tachycardia
Example of sympathomimetic inotropes for D1,D2,b1 and a1 receptors and what does it do
Dopamine
D1:renal VD
Presynpatic D2:peripheral VD by inhibtion of NE release
When are sympathomimetic drugs given
Given IV to acutely ill hospitalized patients in order to provide a short term inc in cardiac contractility
What are phosphodiestrase inhibitors
Do no cause down regulation of b receptor number
Inc intracellular cAMP which is associated with inc patient mortality
Examples for PDI
Milrinone
Enkximone
How do milrinone and enoximone relieve hf
▪️Inc cAMP by inhibtion of phosphodiestrase 3 which breaks down cAMP
▪️Activation of protein kinase which causes phosphorylation of ca2+ channels and inc ca2+ flow
▪️Which will cause positive inotropism and relaxation of resistance in vessels
▪️Which will inc CO and dec preload and afterload relieving heart failure