heart failure3/4/5 Flashcards
what are the 5 treatments of heart failure?
Diuretics Neurohormonal blocking agents If channel inhibitors –ivabradine Vasodilators –hydralazine-ISDN combination Inotropic agents –digoxin
what are the aims of HF-REF treatment?
discover cause/ precipitating factors
relieve/ control signs and symptoms
prevent and reduce risk of hospitalisation
arrest or slow the risk of progressive HF
prolong survival/ reduce mortality
what is the integrated approach to treating HF-REF ?
general: reduce cardiac workload/ decrease salt intake/ smoking and alcohol moderation
drug treatment
other: heart transplant
what are the hallmarks( indications) of CHF?
reduced cardiac output
raised atrial / ventricular filling pressures
progressive deterioration in cardiac function
what are the 3 treatment goals of HF-CHF?
improve cardiac output (i.e. decrease forward failure)
reduce atrial / ventricular filling pressures (i.e. decrease venous return/preload decrease backward failure)
arrest or reverse myocardial remodelling
what are the 3 treatment strategies for CHF?
- myocardial stimulation
- reduce cardiac workload
- arrest or reverse of cardiac remodelling
how do you myocardial stimulate?
increase myocardial contractility- with inotropic agents(digoxin, -adrenoceptor agonists, etc)
how do you reduce cardiac workload?
reduce afterload / preload-with diuretics, vasodilators, etc
how do you arrest or reverse cardiac remodelling?
inhibit chronic neurohormonal activation –with ACEIs, -blockers, ARBs, ARNIs, & aldosterone antagonists
which models are symptom relief?
cardiorenal model (Diuretics•Inotropes) and cardiocirculatory model(Inotropes•Vasodilators)
which model aims to prevent disease?
neurohormonal model (ACEIs•bblockers•ARBs•Aldosterone antagonists•ARNIs)
what are diuretics?
anionic, cationic or uncharged molecules at physiological pH
enter renal tubules via glomerular filtration or active secretion
interfere with tubular solute and/or water reabsorption
what are the 5 main subtypes of diuretics and what are they classified according to?
classified according to chemistry, site of action and MOA
what are the 5 subtypes of diuretics?
1-Osmotic diuretics –mannitol
2-Carbonic anhydrase inhibitors –acetazolamide
3-Thiazides & thiazide-related agents -Bendroflumethiazide*
4-Loop diuretics, types I & II –ethacrynic acid, furosemide*
5-Potassium sparing agents
what is the site and MOA of thiazide diuretics?
inhibit active exchange of Na+, Cl-in the distal convoluted tubule
what is the site and MOA of potassium sparing diuretics?
Inhibit reabsorption of Na+in the distal convoluted and collecting tubule
what is the site and MOA of loop diuretics?
Inhibit exchange of Na+, K+, 2Cl-in the thick segment of the ascending loop of Henle
what is the mechanism of diuretics?
1- increase salt and water excretion (diuresis)
- decrease effective plasma vol/ dec venous return and preload
2-arterial/ venodilation
what are the clinical uses of diuretics in CHF?
to prevent fluid retention and the elimination of congestive symptoms
indicate CHF patients with predisposition to fluid retention
what should be avoided with diuretics?
avoid COX 2 inhibitors and NCAIDS
avoid monotherapy-combine with ACEIs, -blockers, ARBs, ARNIs, etc
what are the adverse effects of thiazide and loop diuretics?
depletion phenomenon –hypokalaemia, hyponatremia hypomagnesaemia, hypovolaemia (L)
retention phenomenon –hyperuricemia, hypercalcemia (T)
metabolic changes –hyperglycaemia & hyperlipidaemia (T)hypersecretion of renin & aldosterone
what are the adverse effects of potassium-sparing diuretics?
retention phenomenon –hyperkalaemia
what 3 neurotransmitters contribute to neurohormonal activation HF
ANG 2, aldosterone and norephrine
what are the 5 available drugs for the neurohormonal blockade?
1-Angiotensin converting enzyme inhibitors (ACEIs)-
2-b-adrenoceptor antagonists (b-blockers)
3-Angiotensin II receptor antagonists (ARBs)
4-Aldosterone receptor antagonists
5-Angiotensin II receptor-neprilysin inhibitors (ARNIs)
what is the MOA of ACEIs?
inhibition of ACE by:
decreasing ang 2 production
INCREASING bradykinin activity
how does ACEIs increase bradykinin activity?
by inhibiting Kinase 2- to prevent the inactive form being formed
what happens when you suppress ANG 2 formation?
decrease in peripheral vasoconstriction- decrease SVR
decreased aldosterone release
decrease plasma volume - decrease cardiac stimulation decrease cardiac remodelling decrease SNS activation -decrease SVR & cardiac remodelling
what happens when you promote bradykinin activity?
1 increase peripheral vasodilatation increase SVR 2increase prostaglandin release- increase vasodilatation- increase SVR
what happens when aldosterone is released?
decrease in PV - decrease congestive symptoms
when do you give ACE inhibitors?
all patients with LV systolic dysfunction (LVEF
less than 40%)
Asymptomatic patients with LV dysfunction
All NYHA II-IV patients (unless contraindicated)
how do you dose ACE inhibitors?
start at low doses
up-titrate to clinically proven effective doses (every 2 weeks)
heck BP, renal function and serum K+& Na+–at initiation, 1-2 weeks after initiation, and after each dose increment
avoid fluid retention
should dose of ACE inhibitors be determined by symptoms?
no