NUR 239: Pharmacotherapeutics of CV Disorders
NUR 239: Pharmacotherapeutics of CV Disorders
Mennonite College of Nursing @ Illinois State University
N 239: Pathphysiology and Pharmacotherapeutics I
Cardiovascular Study Guide II—CV Disorders
Hyperlipidemia and Atherosclerosis
See: Detailed Overview of Hyperlipidemia See: Update on Cholesterol and triglycerides
Elevated levels of blood lipidsàlead to atherosclerosis
Atherosclerosisàheart attack, stroke, and other cardiovascular events.
Lipids—cholesterol and triglycerides
Cholesterol: waxy, fatlike substance essential to growth and viability of body cells
- Component of cell membranes
- Used in synthesis of steroid hormones
- About 7% circulates as blood serum and contribute to atherosclerotic plaques in arteries
Triglyerides: chemical form of most fats in food and in the body
- Stored in adipose as energy source
- Major component of VLDLs and chylomicrons
Lipids are encapsulated by lipoproteins–special fat-carrying proteins for transport in blood. (carry cholesterol and triglycerides)
- HDL—high-density lipoprotein—carries cholesterol to liver
- LDL—low-density lipoprotein—carries cholesterol back to liver or cholesterol dependent pathways (70%) and some to the nonreceptor dependent pathway (30%)
- VLDL- very low density lipoprotein – carries cholesterol to blood vessels
- Chylomicrons—carries triglycerides & cholesterol after ingestion/absorption from GI tract and carry to skeletal muscle for energy or fat for storage
2 sites of lipoprotein synthesis:
Liver—Synthesizes and releases VLDL & HDL; removes LDLs
Small intestine—synthesizes chylomicrons
Labs to know: fill in from ATP III guidelines
1. Total Blood cholesterol levels in adults:
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Desirable: <200 mg/dl—low risk
Borderline-high: >240 mg/dl—risk doubles
High: >260 mg/dl—risk triples
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2. HDL levels : “good guys”
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Protective: >60 mg/dl
Increased risk: <35
Usually seen: 40-50
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3. LDL levels: “bad guys”
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Optimal: <100 or 130 mg/dl
Near-optimal: <100-129
Borderline high: 130-159
High: 160-189 |
4. Triglycerides:
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Optimal: <150 mg/dl
high: |
Hypercholesteremia:
Primary
- elevated cholesterol levels that develops independent of other health problems or lifestyle behaviors.
- May have a genetic basis (defective synthesis of apoproteins, lack of receptors, defective receptors). Familial hypercholesterolemia
NUR 239: Pharmacotherapeutics of CV Disorders
Secondary
- associated with other health problems and behaviors.
- Caused by obesity with high-caloric intake
- Metabolic disorders such as diabetes mellitus.
- blood cholesterol levels at least once every 5 years after age 20.
Atherosclerosis
- Def: a type of arteriosclerosis or hardening of the arteries.
- Characterized by formation of fibrofatty lesions in intimal lining of large and medium-sized arteries (coronaries most common); build-up of plaque in the lumen of arteries
- Leading cause of cardiovascular disease and death among men/women in US
- Development of lesions in arteries which gradually occlude them
Atherosclerotic lesions characterized by:
- Accumulation of intracellular and extracellular lipids
- Proliferation of vascular smooth muscle cells
- Formation of scar tissue and connective tissue proteins.
- Click here to see slides depicting varying degrees of atherosclerosis
Managing Hyperlipidemia— Report of ATPIII (Adult Treatment Panel) for Detection , Evaluation & Treatment of high blood cholesterol in adults
Patient ed website using these new guidelines: http://www.nhlbi.nih.gov/chd/
Prevention IS KEY
Step I—assess blood lipoprotein levels
Step 2—identify presence of atherosclerosis/ risk of coronary heart disease (CHD)
Step 3—identify major risk factors : cigarette smoking, hypertension, low HDL, premature CHD fam history, age
Step 4—If 2+ risk factors, determine 10 year risk of CHD
Step 5—Determine risk category
Step 6—Initiate therapeutic lifestyle changes (TLC)
- TLC Diet–
- Weight loss
- Increased exercise
Step 7—add drug therapy—Work by affecting cholesterol production, increasing intravascular breakdown, or removing cholesterol from bloodstream.
Medications to treat Hyperlipidemia
“Statins”: HMG-CoA reductase inhibitors à inhibit enzyme needed for hepatic synthesis of cholesterol so <LDL, VLDL trig. <inflamm
Prototype: Atorvastatin
Other key drugs:
Rosuvastatin, simvastatin
Name clue: “statin”
Actions:
Adverse Effects: nausea, constipation, diarrhea RARE myopathy, rhabdomylosis
Teteratogenic
Nursing Implications: give with food, teach pt to notify if has muscle aches
Bile acid-binding resins:
Prototype: Cholestyramine (Questran)
Other key drugs:
Name clue: “Chol”
Actions: binds bile acid in intestine so are lost in stool, liver breaks down cholesterol
Stays in intestine, not bloodstream
Adverse Effects: GI-constipation, bloating, flatulence
Nursing Implications: very safe; increase fluids, take 1 hour before or 4 hours after other meds, used with statins
Nicotinic acid
Prototype: Niacin
Other key drugs:
Name clue: “Ni”
Actions: prevents fatty acids from reaching liver, so < cholesterol and trig synthesis, increases HDLs
Adverse Effects: skin flushing, pruritus, GI irritation, hyperglycemia
Nursing Implications: take with food, take ASA 325mg 30 minutes before Niacin
Fibric acids
Prototype: Gemfibrozil (Lopid)
Other key drugs:
Name clue: “Fib”
Actions: increases oxidation of fatty acids in liver, lowers triglycerides and increases HDLs
Adverse Effects: GI upset, diarrhea; increase gallstones
Nursing Implications: Don’t use with statins-increases risk of rhabdomylosis (muscle dz)
Metabolic Syndrome (used to be called Syndrome X)—read more about it
- Syndrome (cluster of symptoms and disorders) associated with high incidence of cardiac disease and stroke 2/2 hyperlipidemia, atherosclerosis
- Caused by insulin resistance (inherited or due to obesity) and resultant hyperinsulinemia which leads to
- Activation of sympathetic nervous system, increasing cardiac output
- Increased peripheral vascular resistance and renal sodium retention à HTN
- Increased blood lipids and accelerated atherosclerosis
- Diagnosed when a person has 3 or more of the following “metabolic risk factors” for heart disease:
- Hypertension (BP > 130/85)
- low HDLs (<40 mg/dl men; < 50 mg/dl,women)
- high triglycerides (>150 mg/dl)
- Truncal obesity (apple shape)
- Fasting blood sugar > 110 mg/dl
- Can be treated with weight loss, exercise—if needed will add medications for hypertension & dyslipidemia
Hypertension (HTN; High blood pressure)
Primary HTN 90% of cases of HTN
- chronic elevation in blood pressure occurring without evidence of other disease
- Diagnosed when blood pressure exceeds 140/90
- Also called Essential HTN
- No specific identifiable cause
Secondary HTN— only 5-10% of cases (secondary to something else, may be something else causing it)
- elevation of blood pressure resulting from some other disorder
- Renal disease
- Most acute kidney disordersàdecreased urine formation, retention of salt/water, hypertension.
- Reduced renal blood flowàaffected kidneys release excessive amounts of reninàincreasing circulating levels of angiotensin IIàarteriolar vasoconstriction
- Disorders of Adrenocorticosteroid Hormones
- These hormones facilitate salt and water retention by kidney
- Salt-restricted diet reduces HTN
- Pheochromocytoma
- Very rare tumor of chromaffin tissue, which contains sympathetic nerve cells
- Tumor commonly located in adrenal medulla.
- Tumor cells produce and secrete epinephrine and norepinephrine.
- Coarctation of Aorta
- Narrowing of the aorta, reducing blood flow to lower parts of body and kidneys.
NUR 239: Pharmacotherapeutics of CV Disorders
Malignant Hypertension
- Accelerated and potentially fatal form of disease
- Characterized by sudden marked elevations in BP
- May include intense arterial spasm of cerebral arteries
- Injures walls of arterioles and may cause intravascular coagulation and fragmentation of RBC
- Renal damage
- needs immediate and rigorous medical treatment
Assessment & Treatment of HTN: EBP Approach: Guidelines from the Joint National Committee on Detection, Treatment and Prevention of Hypertension (JNC 7)
- take BP: see JNC 7 Classification
Category |
SBP |
DBP |
Normal |
<120 |
<80 |
Pre-HTN |
120-139 |
80-89 |
HTN, Stage 1 |
140-159 |
90-99 |
HTN, Stage 2 |
>160 |
>100 |
- Identify risk/ contributing Factors:
- Family hx
- Age-related changes in BP
- Race—HTN more prevalent/severe in African Americans than whites.
- High salt intake
- Obesity
- Hyperinsulinemia: over secretion of insulin into the blood; happens before diabetes
- Excess alcohol consumption
- Low intake of Potassium, Calcium, and Magnesium
- Stress—mostly causes transient alterations in BP
- Oral contraceptive drugs
- Diseases causing secondary HTN
3. Signs and Symptoms
-No early symptoms—“the silent killer”
-Later symptoms
- Headache
- Nocturia—indicating that kidneys are losing ability to concentrate urine
Target Organ Damage
- Blood vessels: major risk for atherosclerosis:
- Heart:
- Atherosclerosisàheart failure, stroke, coronary artery disease, and peripheral artery disease.
- HTN increases workload of left ventricle by increasing pressure against which heart must pump to eject blood into systemic circulationàleft ventricular hypertrophy.
- Left ventricular hypertrophyàmajor risk factor for ischemic heart disease, cardiac dysrhythmias, sudden death, congestive heart failure.
- Kidneys: nephrosclerosis, common cause of renal insufficiency.
- Eyes: hypertensive retinopathyàbleeding, macular/optic nerve swelling, blindness
Treatment of HTN
- Treatment Goal: BP <140/90 mmHg for everyone under 60, >60 years 150/90 mm/Hg
- Majority of patients will require two medications to reach goal. (new guideline goal is relaxed)
Step 1: Lifestyle modifications
Weight reduction
- Regular physical activity
- Modification of alcohol intake
- Smoking cessation
- DASH diet: Increased intake of potassium, calcium, and magnesium (dietary, approach, stop, hypertension) more fruits and veggies and lowfat, lower sodium than TLC
- Decreased sodium
- Use of relaxation and biofeedback
Step 2: Initiate antihypertensive medications – see JNC 7 for choice of initial drugs
- most common first-line drug categories are “ABCD” categories (see meds table)
- A = Angiotensin Converting Enzyme (ACE) inhibitors or Angiotensin II receptor blockers (ARBs)
- B = Beta Blockers (BB)
- C= calcium channel blockers (CCB)
- D = Diuretics
- JNC suggests starting with “D” –Diuretics, specifically thiazide diuretics
Step 3: Adjust medications (change dosage, add medications from other categories) to achieve BP goal with minimal AEs. NUR 239: Pharmacotherapeutics of CV Disorders.
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Common Medications used to treat Hypertension
FIRST LINE MEDICATIONS:
ACE Inhibitors (ACE = angiotensin converting enzyme)
Prototype: Captopril (Capoten)
Other key drugs: Lisinopril (Zestril)
Name clue: “pril”
Actions: block angiotensin converting enzyme from converting angiotensin I to angiotensin II
- Vasodilation (due to blocking angiotensin II)
- Decreased sodium and water retention (due to blocking aldosterone)
Adverse Effects:
- Dry cough in ~10-20%
- Sometimes—hyperkalemia in pts with DM or renal disease who are taking NSAIDS, K supplements, spironolactone
- Rare but serious: neutropenia, proteinuria, angioedema
- Contraindicated in pregnancy
Nursing Implications:
- A key drug to treat HTN and HF with few AEs
- First line drug to treat HTN in people w/ DM 2/2 slowing progression of renal impairment
ARBs—Angiotensin II receptor blockers
Prototype: Losartan (Cozaar)
Other key drugs : Telmisartan (Micardis)
Name clue: “sartan”
Actions: block angiotensin II receptor sites so block its action
Adverse Effects:
- Contraindicated in pregnancy
Nursing Implications:
- “cousins” to ACE inhibitors—same actions, fewer AEs (less cough, hyperkalemia)
- Takes 3-6 weeks to reach maximal BP lowering effect
**IF HTN AND CHRONIC KIDNEY DISEASE ARB’S or ACE’S ARE USED**
Beta-blockers NOT FIRST LINE FOR HTN ANYMORE so SECOND LINE
Prototype: Propanolol (Inderol) (1st gen)
Other key drugs: Atenolol (Tenormin) (2nd gen)
Metoprolol (Lopressor /Toprol)
Name clue: “olol”
Actions: block b1 receptors in heart causing decrease HR and contractility
3 generations of BBs with different effects:
- 1st gen: nonselective– block both b1 and b2 receptors so also causes bronchoconstriction
- 2nd gen: cardioselective: block b1 receptors only so only act on the heart
- 3rd gen: vasodilating: block b1 and a1 so also cause arterial dilation
Adverse Effects:
- Bradycardia, bronchospasm (if 1st gen, non-selective BB), orthostatic hypotension
- Use cautiously with in clients with Asthma, COPD, DM (can lead to and mask symptoms of severe hypoglycemia)
- DO not use in people with heart block
- Do not stop abruptly if have CADà could lead to angina, MI
Nursing Implications
- Key drug in HTN, HF, arrhythmias (also used for migraines, anxiety)
- Take apical pulse and BP before administering: hold if P < 50-60 or BP < 90- 100 and notify prescriber
Calcium-Channel Blockers
Key drugs: Nifedipine (Procardia) (dilates arterioles)
Amlodipine (Norvasc) (dilates arterioles)
Diltiazem (Cardizem) (acts on arterioles and heart)
FOCUS ON PINE because others focus on arrhythmias
Actions: Block calcium ion channels in smooth muscle in peripheral & cardiac arterioles and in cardiac muscle, thus
slowing contraction and in SA and AV nodes slowing node firing
Adverse Effects:
- Constipation
- Flushing
- Palpitations or bradycardia
- Peripheral edema
- Worsening HF
Nursing Implications:
- Key drug in HTN, angina, arrhythmias
Diuretics
- There are several classes of diuretics
- All act on the kidney to increase urine output: this will decrease blood __________ and ___________
- Used for: treatment of HTN, diuresis (removal of excess fluid volume), HF
- Thiazide diuretics (safest because slow onset, fairly weak, and stop working when lose excess fluid)
Prototype: HCTZ (ie hydrochlorothiazide) (Hydrodiuril)
Actions: block Na and CL reabsorption in renal tubule, so increase loss of Na, CL, K, water in urine
Adverse Effects
Nursing Implications
- Safest of the diuretics; slower onset, weaker diuretic– will not cause dehydration
- Teach pt to increase dietary sources of potassium
- Pts may need potassium supplements
- Monitor fluid status: VS, daily weight, edema
- Loop diuretics (much stronger, act on different places in kidnets, fast onset, don’t quit working àno ceiling effect)
Prototype: Furosemide (Lasix)
Actions:
- block Na and CL reabsorption in Loop of Henle, so increase loss of Na, CL, K, water in urine
- Very strong and very fast acting
- Up to 10x greater diuresis than thiazides
Adverse Effects:
- Hypokalemia-low potassium
- Severe dehydration
- Hypotension
- Hearing loss (ototoxicity)
Nursing Implications
- No ceiling effect—will continue working (causing diuresis even to the point of severe dehydration)
- Carefully monitor fluid status: I & O, VS, daily weight, edema
- Teach pt to increase dietary sources of potassium
- Pts may need potassium supplements
- Potassium-sparing diuretics:
Prototype: Spironolactone (Aldactone )
Other key drugs: triamterene
Actions: blocks aldosterone (spironolactone) or acts directly on renal tubule to increase loss of Na (and water) in urine,
and retain K
Adverse Effects:
Nursing Implications
- Weak diuretics; Usually used in combination with thiazide or loop diuretic to prevent excessive K loss
- (triamterene is a component of many combination diuretics such as Dyazide (HCTZ +
triamterene)
- Teach pts to avoid dietary sources of potassium and potassium supplements
- Don’t use in patients with renal disease
SECOND LINE MEDS
Alpha-Blockers
name clue: |
Prazosin (Minipress) Doxazosin-Cardura |
Block a receptors in arteries à vasodilation; 1st dose phenomenon; take at HS |
Centrally acting |
Alpha Agonist Clonidine-Catapres |
Block norepinephrine realease in brain à decreases HR and contractility |
Direct Vasodilators |
Hydralazine-Apresoline Nitroglycerin-NitroBid (IV) |
Do not stop abruptly à high BP |
General Nursing Implications of antihypertensives:
- AEs more likely in elders, those with renal disease and/or DM, and with multiple or large doses of HTN meds
- Teach pts to:
- take at same time each day and not skip doses
- Monitor BP, P and weight
- Watch for orthostatic hypotension
- Don’t stop suddenly
See interactive informational website aimed at consumers: http://www.nhlbi.nih.gov/hbp/index.html
NUR 239: Pharmacotherapeutics of CV Disorders
Heart Failure:
- Insufficient CO for demand
- Inability of heart to supply sufficient blood to meet metabolic demand (O2 need of tissues)
- Impaired pumping ability of heart
- Accompanied by congestion of body fluids
- Not a disease, but a syndrome
Cardiac output: amount of blood heart pumps each minute or volume of blood ejected by ventricle into the circulation per minute
CO=stroke volume * heart rate. CO = SV x HR
–Ave. adult = 3.5 – 8.0 L/min.
Either > HR or > SV or both will > Cardiac Output
Cardiac reserve: Ability of the normal heart to > CO up to 5 times the resting level to meet increased demands = 5 (4 – 8 LPM)
In Heart Failure, there is little if any cardiac reserve…cannot >CO more
Low CO triggers Compensatory Mechanisms:
- Most rapid response (minutes) : Sympathetic Nervous System Stimulation:
- Increases heart rate (b1)
- Increases contractiltiy (b1)
- Increases venous return through vasoconstriction (> preload)
- Renal Retention of Fluid (days):
- stimulation of renin-angiotensin-aldosterone system
- angiotensin II –> vasoconstriction
- Aldosterone –> kidneys save Na & water
- happens within days
- Cardiac remodeling (months):
- Ventricular dilation: > length of myofibrils (due to chronic stretch) and > heart chambers
- Ventricular hypertrophy:> size (diameter) of myofibrils so >muscle mass of LV
Short-term effects: all increase CO
Long-term effects: weaken heart
Heart Failure
- Pumping ability of heart impaired –> low perfusion of organs/ tissues
- Often accompanied by congestion of body tissues –> edema, pulmonary congestion
Overviews—heart failure online AHA site aimed at consumer education: http://www.americanheart.org/presenter.jhtml?identifier=1486
From the NIH: http://www.nhlbi.nih.gov/health/dci/Diseases/Hf/HF_WhatIs.html
Causes of HF: Pathophysiology |
examples |
Myocardial Diseases
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Heart attack, when damages heart muscle |
Valvular Heart diseases
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Mitral valve prolapse |
Congenital heart defects
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Born with it |
Constrictive Pericarditis
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Swelling, squeezes heart |
Excessive work demands
|
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Types or Classifications of Heart Failure
High-Output vs. Low-Output Failure
High—uncommon type caused by excessive need for cardiac output.
Low—caused by disorders that impair pumping ability of heart.
Systolic vs. Diastolic Failure
- Systolic Failure—Impaired ejection of blood during systole
- Involves a decrease in cardiac contractility and ejection fraction
- Commonly results from condition that impair contractile performance or hemodynamic conditions producing volume overload or pressure overload
- Ejection fraction = normal ventricle ejects 50-65% of blood in ventricle during contraction
- Ejection fraction declines progressively during systolic heart failure.
- Diastolic Failure—impaired filling of heart during diastole
- Characterized by smaller ventricular chamber size, ventricular hypertrophy, and poor ventricular compliance (ability to stretch during filling)
- Causes include those that restrict diastolic filling, those that increase ventricular wall thickness and reduce chamber size and those that delay diastolic relaxation.
Right-Sided vs. Left-Sided Failure
- Right and left ventricles must maintain equal output to function effectively
- Long-term heart failure usually involves both sides
- Right-Sided Failure—cor pulmonale
- Caused by conditions that restrict blood flow from Rt. Ventricle into lungs—ex. stenosis or regurgitation of tricuspid or pulmonic valves and Pulmonary diseases
- Decreased pumping of deoxygenated blood from systemic circulation into pulmonic circulation
- Accumulation / congestion / back up of blood in venous system leading to fluid retention and edema in peripheral tissues and abdominal organs
- Left-Sided Failure
- Caused by heart muscle or heart valves problems – most common: acute myocardial infarction and cardiomyopathy
- Results in:
- decreased cardiac output—less oxygenated blood pumped into systemic circulation
- increased left atrial and ventricular end-diastolic pressures [preload]
- Accumulation / congestion / back up of blood in pulmonary circulation leads to fluid accumulation in the lungs
Clinical Manifestations of CHF:
- Fluid retention and edema (due to congestion from right-sided failure)
. Pitting edema
. Ascites—fluid accumulation in the abdomen
- Congestion of hepatic veins that drain into inferior vena cava
à impaired liver function and hepatic cell death
à Congestion of GI tract may interfere with digestion and nutrient absorption
- Jugular vein distention [JVD]
- Nocturia—nightly increase in urine output
- Respiratory manifestations (due to congestion from left-sided failure)
- SOB
- Exertional dyspnea—related to increase in activity
- Orthopnea—SOB occurring when person is supine
- Paroxysmal nocturnal dyspnea—occurs during sleep
- Chronic dry, nonproductive cough
- Cardiac asthma—bronchospasm due to congestion of bronchial mucosa causing wheezing and breathing difficulty
- Cheyne-Stokes respiration (periodic breathing)—Slow waxing and waning of respiration
- Fatigue and weakness
- Cyanosis
Diagnostic Methods
- Electrocardiograph—indicate atrial or ventricular hypertrophy, underlying disorder of cardiac rhythm, or conduction abnormalities
- Chest radiographs—size and shape of heart and pulmonary vessels, pulmonary edema
- Echocardiograph—reveal size and function of cardiac valves and size and motion of both ventricles
- Radionuclide angiography and cardiac catheterization—describe underlying causes
- Invasive hemodynamic monitoring
- Central venous pressure (CVP)—reflects amount of blood returning to heart
- Pulmonary capillary wedge pressure (PCWP)—monitors pulmonary capillary pressures in direct communication with pressures from left heart
NUR 239: Pharmacotherapeutics of CV Disorders
- Blood tests: BNP: B type natriuretic hormone (or brain naturetic hormone)
- a cardiac hormone secreted by ventricles due to pressure or volume overload
- is a marker for heart failure– used for diagnosis and monitoring
- BNP levels go up with uncompensated HF; are normal with no HF
- <100 pg/mL = no heart failure
- 100 – 200 = compensated HF (Class II ~ 200)
- 200 – 400 = moderate HF (Class III)
- > 400 = severe HF
7. Two classification systems
NY Heart Association Functional Classification of Patients with Heart Disease
—based on how patient feels and limitations with physical activity
–person can go back and forth between categories based on symptoms
I |
No symptoms and no limitation in ordinary physical activity
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BNP ~ 100
|
II
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Mild symptoms and slight limitation during ordinary activity. Comfortable at rest
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BNP ~ 200
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III |
Marked limitation in activity due to symptoms, even during less-than-ordinary activity. Comfortable only at rest. |
BNP ~ 350 |
IV |
Severe limitations. Experiences symptoms even while at rest |
BNP ~ 1000 |
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http://www.clinlabnavigator.com/Tests/Flash/BTypeNatriureticPeptide.swf |
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AAC/AHA Heart Failure Guidelines and Classification System—see diagram posted in module –classification based on progressive nature of HF—can’t go back to lower level
–includes recommendations for treatment
NUR 239: Pharmacotherapeutics of CV Disorders
Medications used to treat Heart Failure
First line drugs: |
Key drugs in this class used in HF |
Key Points |
ACE Inhibitors or ARBs: block RAA–
block angiotensin II production
–vasodilation arterioles
–vasodilation venules
block aldosterone production
–less Na and H20 retention in kidney
favorable impact on cardiac remodeling |
ACE:
- Captopril (Capoten)
- Enalapril (Vasotec)
- Lisinopirl (Zestril)
ARB:
- Losartan (Cozaar)
- Vlasartan (Diovan)
|
All pts with HF should take ACE inhibitors
Reduce symptoms, improve functioning and prolong life
ARBs can be used instead if pt has difficulty with AEs of cough and/or angioedema
see AEs, nursing implications in HTN notes |
Beta-blockers
–lower heart rate and decrease cardiac workload
–3rd generation BBs also cause vasodilation
|
only cardioselective B-Blockers:
- carvedilol (Coreg)– 3rd gen
- bisoprolol (Zebeta) –2nd gen
- sustained release metoprolol (Toprol XL)
|
Most pts with HF should take BBs
improve cardiac function, reduce symptoms, prolong survival
protect heart from excessive SNS stimulation
need to start with low dose and monitor closely
see AEs, nursing implications in HTN notes |
Diuretics
increase urine output, thus decrease fluid overload |
Thiazides for most (HCTZ)
Loop– furosemide (Lasix) for more severe edema |
Diuretics used in pts with congestive symptoms–
fluid volume excess–edema, JVD, crackles, dyspnea, orthopnea, etc
see AEs, nursing implications in HTN notes |
Second line drugs: Add these drugs in Stage C or D as needed |
Cardiac Glycosides (Digitalis):
Digoxin (Lanoxin)
positive inotropic effect: increases contractility
negative chronotropic effect: slows SA and AV node impulses
|
-improves CO, reduces symptoms but does not prolong life
very dangerous drug:!!
- long 1/2 life
- very narrow therapeutic window– small difference between therapeutic and toxic dose
- optimal therapeutic blood level:0.5-0.8ng/dl
- if have hypokalemia, can develop toxicity at normal blood level
- early toxicity S&S: anorexia, nausea & vomiting
- later toxicity S&S: vision changes– halos, blurry, yellow tint, fatigue, CV arrythmias– can vary from bradycardia (AV block) to ventricular fibrillation
- drug interactions with lots of other meds
nursing implications:
- monitor K– if on diuretic, should be on K supplements
- assess apical pulse before admin– hold if <60 or >120 or a change from pts normal and call provider
|
Vasodilator drugs
- produce relaxation of vascular smooth muscle
- reduce afterload (through arterial dilation)
- reduce preload (though venous dilation)
|
nitrate: isosorbide dinitrate (venous dilation)
hydralazine (Apresaline) (arteriolar dilation) |
often are combined
- orthostatic hypotension and reflex tachycardia
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aldosterone antagonists
· block actions of aldosterone
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spironolactone (Aldactone)
|
promotes cardiac remodeling, reduces symptoms and prolongs life
see AEs, nursing implications in HTN notes |