Treatment of HF Flashcards
What is HF?
*Heart failure (HF) is a complex, progressive disorder in
which the heart is unable to pump enough blood to
meet the needs of the body
*It is caused by
decreased coronary blood flow that is
insufficient to meet the oxygen demands of the
myocardium, leading to ischemia
What drugs are used for chronic HF
diuretics, ACE inhibitors, ARBs, beta blockers, Aldosterone receptor agonists, Cardiac glycosides (digoxin), vasodilators
What drugs are used for acute HF
Diuretics, vasodilators, oxygen, beta receptor agonists (dobutamine)
Describe ACE inhibitors and HF
*ACE inhibitors decrease vascular resistance (afterload) and venous tone (preload), resulting in increased cardiac output
*ACE inhibitors are indicated for patients at all stages of LHF, asymptomatic and symptomatic HFrEF
*Adverse effects: persistent dry cough, renal insufficiency, hyperkalemia, postural hypotension, fetotoxic
Describe ARBs and HF
*block AT1 receptor on the heart, peripheral vasculature and kidney, reduce preload and afterload
*mainly used for patients who cant tolerate ACE inhibitors
Name ACE inhibitors
-prils
Captopril
Enalapril
Fosinopril
Lisinopril
Quinopril
Name ARBs
-sartan
Candesartan
Losartan
Telmisartan
Valsartan
Describe aldosterone antagonists and HF
Patients with HF have elevated levels of
aldosterone due to angiotensin II stimulation
*Spironolactone is a direct antagonist of aldosterone, which
prevents salt retention, myocardial hypertrophy, and
hypokalemia
* Eplerenone is also an antagonist of aldosterone but with
lower incidence of endocrine-related side effects
Describe beta blockers and HF
*decrease in HR and inhibition of renin release from the kidneys; decrease workload and oxygen consumption
*carvedilol is a nonselective beta blockers that also blocks a-receptors
*Bisoprolol and Metoprolol are B1 selective antagonists
*AE: bradycardia, hypotension, fatigue, dizziness
Describe diuretics and HF
*Diuretics relieve pulmonary congestion and peripheral
edema
*Reduce afterload and decrease preload
* Loop diuretics are the most commonly used diuretics in HF
*Furosemide, Metolazone, Bumetanide, Torsemide
What drugs are used as vaso and venodilators? what are the adverse effects?
*Nitrates are commonly used venous dilators to reduce preload for patients with chronic HF
*Arterial dilators, such as hydralazine reduce systemic arteriolar resistance and
decrease afterload
*A fixed combination of hydralazine and isosorbide dinitrate improve symptoms and survival in black patients with HF
*Adverse Effects: Headache, hypotension, and tachycardia are common adverse
effects with this combination
What is the MOA of ionotropic drugs?
*Positive inotropic agents enhance cardiac
contractility thus, increase cardiac output
*Inotropic action is the result of an increased
cytoplasmic calcium concentration that
enhances the contractility of cardiac
muscle
*All positive inotropes have been associated
with reduced survival
*only used for a short period of time
What is the MOA of Digoxin?
- Regulation of cytosolic calcium concentration: By inhibiting the Na+ /K+ -ATPase pump, increase in free Ca2+ , thereby leading to increased cardiac contractility.
- Increased contractility of the cardiac muscle: Digoxin increases the force of cardiac contraction
What are the adverse effects of Digoxin?
*It has a very narrow therapeutic index
*Anorexia, nausea, and vomiting may be initial indicators of toxicity
*Blurred vision
*Cardiac arrhythmias
*Hypokalemia
Describe Milrinone and Dobutamine
Milrinone is a phosphodiesterase inhibitor that increases the
intracellular concentration of cyclic adenosine monophosphate
(cAMP), results in an increase of intracellular calcium and, therefore,
cardiac contractility
* Dobutamine is a β receptor agonist, increases intracellular
(cAMP), which results in the activation of protein kinase, which
increases entry of calcium ions into the myocardial cells and
enhances contraction
