SM 144 Heart Failure Treatment Flashcards
What is Heart Failure?
Heart Failure is a syndrome where the heart cannot produce enough cardiac output or can only do so at the cost of increased filling pressures
What causes HFrEF?
Impaired contractility + Increased afterload
What causes HFpEF?
Impaired diastolic filling
What are the Stages of HF and are they unidirectional or bidirectional?
The stages span A - D and represent the extent of damage a patient has endured; A = high risk, B = damage but asymptomatic, C = HFrEF or HFpEF and symptomatic, D = HFrEF end stage; they are unidirectional because damage cannot be undone
What are the Classes of HF and are they unidirectional or bidirectional?
The Classes span I - IV and represent the symptoms experienced by a patient; I = none while IV = symptoms at rest; they are bidirectional because symptoms can be improved
What is the first step in managing HF?
Prevent it to begin with! Control BP, DM, Lipids, Smoking, and Weight
How does Hypertension relate to HF?
Hypertension can directly lead to HFrEF or cause HFpEF which can then worsen to HFrEF
What are symptoms of HF?
Low exercise capacity, dyspnea, orthopnea, nocturia
What are signs of HF?
Elevated JVP, rales, edema, hepatomegaly
What is BNP?
A biomarker elevated in HF
What tests can be used to diagnose HF?
BNP, EKG, CXR, Swan-Ganz catheterization
What drugs are always indicated in chronic treatment of HFrEF?
ACE-I or ARB or Sacubutril + ARB; Beta Blockers
What Beta Blockers are approved for HF?
Metropolol Succinate, Bisoprolol, Carvedilol
What are the pure venodilators?
Nitrates = reduce preload
What are mixed vasodilators?
Nitroprusside, ACE-I/ARBs, a-agonists, central a2 agonists = reduce afterload + preload
What are the arteriolar dilators?
Hydralazine, Minoxidil, CCB’s = reduce afterload
How does spironolactone affect the RAAS system?
Normally AngII binds the AT1 receptor to produce Aldosterone, which increases Na/Water reabsorption; Spironolactone prevents Aldosterone from binding it’s receptor, decreasing Na/Water reabsorption
How does Sacubutril work?
Sacubutril inhibits Neprilysin, potentiating Bradykinin and causing vasodilation
What are ACE-I’s and ARBs indicated for?
ACE-I and ARB’s are indicated for HF and HTN
How does Sacubutril compare to ACE-I/ARB’s?
Sacubutril is better but more expensive, while ACE-I’s and ARB’s are equivalent
How do Beta agonists work?
Beta blockers bind to an adrenergic receptor to increase inotropy and heart rate, leading to shorter diastole and lower coronary O2 supply
How do Beta blockers treat HF if they reduce inotropy?
Is the short run, Beta Blockers make HF worse due to decreased inotropy lowering CO; however, over time, more Beta receptors are expressed on myocytes increasing sensitivity to adrenergic signaling and contractility
How are Beta1 adrenergic receptors internalized?
B-ARK phosphorylated Beta receptors that are active, allowing B-Arrestin to bind and internalize the receptor, decreasing sensitivity to adrenergic signaling
When is Metropolol Succinate the right Beta Blocker to use?
Purely B1 cardioselective, good choice for asthma
When is Bisoprolol the right Beta Blocker to use?
Purely B1 cardioselective
When is Carvedilol the right Beta Blocker to use?
Combined A1/B2 effects allows for additional vasodilation
How do Mineralocorticoid/Aldosterone Antagonists work?
Spironolactone prevents the binding of Aldosterone to the internal Mineralocorticoid receptor in the Principal Cell, causing diuresis as well as protection against fibrosis
Compare Spironolactone to Eplerenone?
Spironolactone is cheap/generic, relatively nonselective, and is a prodrug with many metabolites; Eplerenone is highly selective for the Mineralocorticoid Receptor; both cause hyperkalemia
How do Nitrates work?
Primarily venodilators that decrease Preload, have minor arteriolar dilation effects that can decrease afterload in high doses
What is Hydralazine and how does it work?
Mechanism unknown, causes smooth muscle relaxation to vasodilate arterioles
What is the evidence based Nitrate of choice for HF?
Isosorbide Dinitrate
What are side effects of Nitrates?
Headache, hypotension
What is Ivabradine?
Selective sinus node inhibitor that alters pacemaker Phase 4 to lower HR; not used often clinically
What is the only evidence based treatment for HFpEF?
Blood pressure control
What drug is most useful for HFpEF?
Spironolactone
How should HFpEF be managed?
Volume control, BP control, Spironolactone, weight + exercise
What causes HF to worsen?
Decompensation events
What are the proarrhtymic effects of Digoxin?
Digoxin can cause almost any arrythmia
How does Digoxin improve HF?
Digoxin is a positive inotrope via Ca/Na potentiation
What can decompensate HF?
Medication non-adherence, high salt diet, increased metabolic demands, increased afterload, decreased contractility
What are signs of congestion?
Orthopnea, elevated JVP, edema, pulmonary rales = “wet”
What are signs of poor perfusion?
Cool extremities, decreased BP, decreased pulse pressure = “cool” + give Nitroprusside
What should be done when a HF patient is “warm and dry”?
Warm = well perfused + dry = no congestion, so reconsider HF diagnosis
What should be done when a HF patient is “warm and wet”?
Warm = well perfused + wet = congested, so diurese the patient and uptitrate HF meds
What should be done when a HF patient is “cool and dry”?
Cool = poor perfusion + dry = no congestion, treat with inotropes + vasodilators (Nitroprusside) + LVAD/Heart Transplant to increase cardiac output/perfusion
What should be done when a HF patient is “cool and wet”?
Cool = poor perfusion and wet = congestion, treat with vasodilators (Nitroprusside) first to increase perfusion and allow for diuresis later, inotropes can improve perfusion but raise mortality
What drugs can be given to treat acute pulmonary edema?
LMNOP; Loop diuretics, Morphine, Nitrates, Oxygen, Positve Pressure Ventilation (BiPap); treat underlying problem later
What do loop diuretics do when treating pulmonary edema?
Loop diuretics acutely venodilate than natriuresis occurs
What does Morphine do when treating pulmonary edema?
Venodilator + lowers sensation of dyspnea
What do nitrates do when treating pulmonary edema?
Venodilator + increase pulmonary venous capacitance
What does oxygen do when treating pulmonary edema?
Increase Oxygen supply during a period of high demand
What does positive pressure ventilation do when treating pulmonary edema?
Improve oxygenation
What can cause acute pulmonary edema?
Elevated BP, ACS, Increased Dietary Na
When should Inotropes be used in HF?
Sparingly because they cause higher mortality, use in Class IV patients (symptomatic at rest)
What are the two types of Inotropes?
B1 agonists + Phosphodiesterase 3 Inhibitors
When B1 agonist is used to treat HF and why?
Dobutamine, which binds B1 and B2 equally; results in increased HR, SV, and vasodilation
How do phosphodiesterase inhibitors work in HF and name one?
Milrinone bypasses the Beta1 receptor to increase cAMP directly to increase contractility
