drug therapy for heart failure Flashcards
what is heart failure aka congestive heart failure (CHF)
complex clinical condition where the heart cannot effectively pump enough blood to meet the body’s O2 and nutritional needs
what can CHF result from?
-impaired myocardial contraction during systole
-imparied relaxation and filling of the ventricles during diastole
-combination of both
other causes (which impait pumping ability or increase cardiac workload)
-hyperthyroidism
-excessive IV fluids or blood transfusions
-antidysrhythmic meds
-CAD (major cause) and HTN
-drugs that cause sodium and water retention (corticosteroids, estrogens, NSAID use)
describe CHF at a cellular level
-dysfunction of contractile myocardial and endothelial cells that line the heart and vessels
-endothelial dysfunction allowa narrowing of vessel lumen (leads to clot formation and vasoconstriction, major factors in CAD and HTN)
may or may not present with congestive s/sx whcih refers to fluid back up in the body
describe normal heart function
-ventricles fill nrmally with blood
-ventricles pump out about 60% of the blood
describs systolic HF
-failure of ventricular contraction
-most common
-reduced ejection fraction
-enlarged ventricles fill with blood
-ventricles pump out less than 40-50% of the blood
descrie diastolic HF
-failure of fillinf og the ventricles
-stiff/noncompliant muscles
-normal ejection fraction
-stiff ventricles fill with less blood than usual
-ventricles pump out about 60% of the blood but may be lower than normal
what are the s/sx of left sided HF
-SOB
-crackles
-dizziness
-activity intolerance
-orthopnea, tachypnea, pulmonary congestion
-cyanosis, restlessness, confusion
what are the s/sx of right sided HF
-weight gain
-JVD
-peripheral edema
-enlarged live and spleen, ascites
-anorexia, complaints of GI distress
-may be secondary to chronic pulmonary problems
what is the goal of treatment for CHF
symptom management
what are some nonpharmacologic management measures for CHF
prevent contributing conditions:
-restrict Na+ intake (lowNa+/heart healthy diet)
-restrict fluid (if hyponatremic)
-promote weight loss (for obese pts)
-reduce physical activity (if symptomatic)
-administer O2 (to reduce dyspnea, workload)
-prpeare for heart transplant (if indicated)
daily weights are also super important
give an example of a cardiac glycoside
digoxin
what is digoxin used to treat
-management of mild/moderate HF -> has positive inotropic effect -> increases cintractility and pumping of the heart
-management of atrial fibrillation -> negative chonotropic effect -> slows the rate of ventricular contraction
what are the therapeutic actions of digoxin
allows more calcium to enter cell -> increases intracellular calcium -> decreases cardiac workload
describe the pharmacokinetics of digoxin
-decrease metabolism in pts with HF
-excreted via the kidneys
what are some adverse effects of digoxin
-weakness
-HA
-drowsiness
-vision changes (yellow halo)
-GI upset/anorexia
-arrythmias
-breast enlargement
what are some nursing implications r/t digoxin
-monitor for improving signs og HF/afib and monitor for toxicity
what are some contraindications of digoxin
PMHx of Vtach/Vfib, HB/sick sinus, acute MI, renal insufficiency, electrolyte abnormalities
what other types of meds are digoxin often given with
ACE inhibitors and ARBs or other diuretics
what makes digoxin a dangerous med?
very narrow therpautic index, requires serum digoxin levels to be drawn
what are normal digoxin levels
0.8-2 ng/ml
below= not therapeutic
above = toxic
what are the signs of digoxin toxicity
-yellow-green halo/visual blurring and color change
-ventricular rhythm changes
-premature ventricular contractions (PVCs)
-N/V, anorexia, abdominal discomfort
-cognition changes
who can develop digoxin toxicity even when serum levels are WNL?
pts with hypokalemia, hypomagnesia, and hypercalcemia
what is the antidote for digoxin toxicity
digoxin immune fab (digibind/digifab)
give ana example of a phosphodiesterase inhibitor
milrinone
describe milrinone
(phosphodiesterase inhibitor)
-long term bridge therapy in heart failure
-increase Ca++ in cell
what are the therapeutic actions of phosphodiesterase inhibitors
increasing the force of onctraction in the ventricle -> posiitve inotropic effect -> relaxes vascular smooth muscle -> systemic and pulmonary vasodilation -> decrease in preload and afterload
describe the pharmacokinetics of phosphodiesterase inhibitors
metabolized in liver and excreted via urine
name some adverse effects of phosphodieserase inhibitors
-potentially fatal ventricular arrythmias
-hypotension
-chest pain
-N/V
-anorexia
-thrombocytopenia
-burning at injection site
what are some nursing implications of phosphodiesterase inhibitors
monitor:
-HR
-BP
-ECG
-BMP labs for Ca++
what are some contraindications of phosphodiesterase inhibitors
-acute MI
-aortic stenosis
-pregnancy
-pulmonary artery stenosis
name an example of a human B type natriuretic peptide
nesiritide
what are natriuretic peptides?
hormones that help maintain sodium and fluid balance = reduces preload and afterload
describe the therapeutic actions of human B type natriuretic peptide
-release increases sodium excretion by the kidneys and diuresis
-direct vasodilation
-increased GFR
where is human B type natriuretic peptide excreted?
kidneys
name some adverse effects of human B type natriuretic peptides
-hypotension
-headache
-nausea and vomiting
-back pain
-ventricular tachycardia
-dizziness
-anxiety
-insomnia
-bradycardia
what are some nursing implications r/t human B type natriuretic peptides
monitor BP and urine output
name a contraindication of human B type natriuretic peptides
SBP less than 90
why are human B type natriuretic peptides not a commonly used med?
bc of the adverse effects and newer, more efficient meds being available
give an example of angiotensin receptor neprilysin inhibitors
sacubitril/valsartan
approved in 2015 - newer drug
combo drug
what are angiotensin receptor neprilysin inhibitors used for
management of chronic HF in pts with reduced ejection fraction
EF is the amount of blood that is pumped out of the ventricles with each contraction
describe the therapeutic actions of angiotensin receptor neprilysin inhibitors
-sacubitril inhibits the enzyme neprilysin, responsible for degradation of atrial and brain natriuretic peptides (BNP)
-the peptides responsible for lowering BP by reducing blood volume along with valsartan (ARB)
please just know that it lowers BP
describe the pharmacokinetics of angiotensin receptor neprilysin inhibitors
-metabolized in liver
-excreted in urine and feces
what are some adverse effects of angiotensin receptor neprilysin inhibitors
-hypotension
-hyperkalemia
-cough
-dizziness
-renal impairment
-angioedema may also occur
what are some nursing implications r/t angiotensin receptor neprilysin inhibitors
monitor HR and BP, as well as electrolytes and adverse effects
what are some contraindications of angiotensin receptor neprilysin inhibitors
-lithium rx
-pregnancy possibility
give an axample of a sinoatrial node modulator
ivabradine
what are SA node modulators used for
reduce risk of worsening HF in pts who have chronic heart failure while they are in the hospital
describe the therapeutic actions of SA node modulators
selective inhibition of the SA node -> decreased firing from the SA nod -> decrease HR -> allows more ventricular filling
describe pharmacokinetics of SA node modulators
-first pass metabolism in liver
-excreted via kindeys
what are some adverse effects of SA node modulators
-bradycardia
-hypotension
-atrial fibrillation
-phosphine (a ring or spot of light caused by pressure on eye orbital)
what are some nursing implications r/t SA node modulators
-HR/BP/cardiac rhythm monitoring
-no grapefruit juice
what are some contraindications of SA node modulators
-acute decomposed HF
-bradycardia
-hypotension
-heart blocks
-sick sinus syndrome
-pacemaker pts
-severe hepatic impairment
name some adjunctive meds used to treat HF
-loop diuretics (furosemide)
-thiazide diuretics (HCTZ, hydrodiuril)
-ACE inhibitor (enalapril)
-ARB (losartan potassium)
-beta adrenergic blockers (propranolol hydrochloride)
-aldosterone antagonists (spironolactone)
