drug therapy heart failure Flashcards
(50 cards)
heart failure is
the hearts inability to pump an adequate blood supply of blood to the body, does not meet body O2 and nutritional needs; a complex clinical condition or collection of symptoms that weaken your heart
the most common cause of heart failure
coronary artery disease: cause narrowing of arteries; cardio myopathy, myocardial infarction, heart valve disease, arrhythmias, emphysema
heart failure may result from
impaired myocardial contraction during systole or impaired relaxation and filling of ventricles during diastole or combination
other causes of HF which impair pumping ability or increase cardiac workload
hyperthyroidism, excessive IV fluids or blood transfusions, antidysrhythmic medications, drugs that cause sodium and water retention (estrogens, NSAIDs, corticosteroids use)
cellular level of HF
dysfunction of contractile myocardial and endothelial cells that line the heart and vessels, endothelial dysfunction allows narrowing of vessel lumen (lead to clot formation and vasoconstriction, major factors in HTN & CAD)
systolic HF
failure of ventricular contraction, reduced ejection fraction, enlarged ventricles (most common) (pump ~40-50% out)
diastolic HF
failure of filling, stiff/noncompliant muscle, normal ejection fraction (pump ~ 60% out)
s/sx of left sided heart failure
SOB, crackles, dizziness, activity intolerance, tachycardia, fatigue
s/sx of right sided heart failure
weight gain, JVD, peripheral edema, fatigue,
normal blood flow
inferior/ superior vena cava -> right atrium -> right ventricle -> pulmonary artery -> lungs -> pulmonary veins -> left atrium -> left ventricle -> aorta -> systemic circulation of body
nonpharmacologic management measures
restrict Na+ intake, restrict fluid(if hyponatremic), promote weight loss(if obese), reduce physical activity(if symptomatic), administer O2 (to reduce dyspnea, workload), prepare for heart transplant
drug therapy for HF
cardiac glycoside, phosphodiesterase inhibitor, human B type natriuretic peptides, angiotensin receptor neprilysin inhibitors, sinoatrial node modulators
drug therapy for HF: cardiac glycoside
digoxin; management for mild-moderate HF = positive inotropic effect= increases contractility and pumping of heart & management of atrial fibrillation = negative chonotropic effect = slows the rate of ventricular contraction
cardiac glycoside action
allows more Ca2+ to enter cell/ increases intracellular Ca2+/ decreased workload of the heart
pharmacokinetics of cardiac glycoside
decreases metabolism in pt’s with HF/ excreted via kidneys
adverse effects of cardiac glycoside
weakness, HA, drowsiness, vision changes, GI upset, arrhythmias, breast enlargement
nursing concerns for cardiac glycoside
monitor for improving signs of HF/ Afib and monitor digoxin toxicity
digoxin has a very narrow therapeutic window which means
it is very hard to dose because you have to keep it in a very small range; if lower -> not therapeutic; if higher -> become toxic (serum: 0.8-2 ng/mL)
contraindications of cardiac glycoside
PMHx Vtach/ Vfib, HB/sick sinus, acute MI, renal insufficiency, electrolyte abnormalities
digoxin can be given with what other medications
ACE inhibitors & ARB’s or other diuretics
signs of digoxin toxicity
yellow-green halo/ visual blurring and color change, ventricular rhythm changes
patients with what electrolyte abnormalities can develop digoxin toxicity when serum levels is WNL
hypokalemia, hypomagnesemia, hypercalcemia
antidote for digoxin toxicity
digoxin immune fab (digibind/ digifab)
phosphodiesterase inhibitor medication
milrinone
