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Taylor
Pharm Cardio
144
Health Care
Graduate
02/25/2011

Additional Health Care Flashcards

 


 

Cards

Term
Complications of HTN
Definition
Cerebral vascular accident (CVA)
Congestive heart failure (CHF)
Myocardial infarction (MI)
Kidney damage
Term
Stages of HTN
Definition
normal less than 120/80
Pre HTN 121-139/80-89
Stage 1 140-159/90-99
Stage two over 160/100
Term
2 mechanisms controlling BP
Definition
Baroreflexes (Sympathetic nervous system
Renin-Angiotensin-Alodosterone system
Term
RAAS
Definition
Renin converts angiotensinogen to antiotensin 1 and ACE enzymes converts angiotensin 1 to angiotensin 2
Term
Effects of Angiotensin 2
Definition
Vasoconstriction, Aldosterone release which causes Na and water retention which leads to increased blood volume which increases BP also causes NE release
Term
Treatments for HTN
Definition
Lifestyle changes,
diuretics- Thiazide and loop
Beta blockers- non and cardio selective
renin-Angiotensin inhibitors- Ace
inhibitors, ARB, renin inhibitors
CCBs dihydropyridine and non dihydro
Alpha blockers
Others
Term
African american response to HTN treatment
Definition
respond better to diuretics, don't respond as well to BBs or ACEIs
Term
Elderly
Definition
respond to CCBs or ACEis and diuretics
more adverse affects from BB and a blockers
Term
1st line of defense for HTN
Definition
Diuretics they are safe, effective, and inexpensive
Term
Thiazide Actions
Definition
Act mainly in distal tubule to ↓ reabsorption of Na (by inhibition of a Na/Cl cotransporter on luminal membrane of DCT)
Initially causes an increase in Na & water excretion (resulting in a decrease in blood volume)
Creates hyperosmolar urine- monitor K⁺ and Mg⁺⁺ (esp. elederly)
Inhibit urinary Ca⁺⁺ excretion
Long-term treatment results in normal plasma volume, but a decrease in peripheral vascular resistance (caused by relaxation of arteriolar smooth muscle)
Term
Thiazide Actions
Definition
Act mainly in distal tubule to ↓ reabsorption of Na (by inhibition of a Na/Cl cotransporter on luminal membrane of DCT)
Initially causes an increase in Na & water excretion (resulting in a decrease in blood volume)
Creates hyperosmolar urine- monitor K⁺ and Mg⁺⁺ (esp. elederly)
Inhibit urinary Ca⁺⁺ excretion
Long-term treatment results in normal plasma volume, but a decrease in peripheral vascular resistance (caused by relaxation of arteriolar smooth muscle)
Term
Thiazide uses
Definition
Reduction of BP
Monotherapy or Combination with other antihypertensives
NOT effective in patients with inadequate kidney function (CrCl < 50 mL/min)
Term
SE of Thiazides
Definition
Electrolyte abnormalities
Hypokalemia
Follow K levels closely in patients prone to arrhythmias
Also monitor K levels closely if taking digoxin
Hyperuricemia-increase serum uric acid by ↓ amount of acid excreted byorganic acid secretory system (may ppt gouty attack)
Hypomagnesemia
Hyperglycemia- due to impaired release of insulin and tissue uptake of glucose
Hyperlipidemia- can cause ↑ in cholesterol and LDL levels bus usually return to normal w/long-term therapy
Term
Kinetics of Thiazides
Definition
Pharmacokinetics
Orally active
Absorption & elimination rates are variable
1 to 3 weeks to produce a stable reduction in blood pressure
Utilizes acid secretory function of the nephron (compete with uric acid for elimination)
Term
Loop Actions
Definition
Inhibit cotransport of N/K/2Cl in luminal membrane in ascending limb of loop of Henle
Reabsorption of these ions is ↓
Most efficacious of diuretic drugs – ascending limb accounts for reabsorption of 25 to 30% of filtered NaCl and downstream sites are not able to compensate for ↑ Na load
Act promptly (even in pts w/poor renal fxn or have not responded to other diuretics)
Cause ↓ renal vascular resistance and ↑
Increase prostaglandin synthesis-helps play a role in diuretic action
Term
Uses for Loops
Definition
Drug of choice for reducing acute pulmonary edema of heart failure
Also used to treat hypercalcemia and hyperkalemia
IV or PO
Very rapid onset when given IV and useful in emergency situations
Term
SE of loop diuretics
Definition
Ototoxicity- especially when used with aminoglycosides
Hyperuricemia-compete w/uric acid for renal & biliary secretory systems →gouty attacks
Acute hypovolemia-severe, rapid reduction in blood vol. can lead to hypotension, shock and cardiac arrhythmias
K⁺ depletion
↓Mg⁺⁺
Term
K sparing Diuretics (spironolactone)
MoA
Definition
Aldosterone Antagonist:
Synthetic steroid that antagonizes aldosterone at intracellular cytoplasmic receptor sites- results in failure to produce proteins normally synthesized in response to aldosterone
Prevents Na⁺ reabsorption and K⁺ and H⁺ secretion
Blood levels of aldosterone are high in most edematous states
Often given w/thiazide or loop diuretics
Term
Spironolactone Uses
Definition
Useful in secondary hyperaldosteronism
Helps prevent remodeling of heart that occurs w/progressive heart failure
Term
SE of Spironolactone
Definition
GI upset and may cause peptic ulcers
May induce gynecomastia in males and menstrual irregularities in females (resembles sex steroids and may act at those receptors)
Hyperkalemia, N, lethargy and mental confusion can occur
Term
Beta Blocker Actions
Definition
Reduction of BP occurs primarily through reduction of cardiac output.
Some inhibition of renin release & possible reduction in sympathetic output from CNS
Selective b-1 receptor blockers are most commonly prescribed: (i.e. metoprolol, atenolol)
Term
Uses for B blockers
Definition
Population subsets
More effective in Caucasians & younger to middle-age patients
Hypertension with co-morbid disease
Previous MI, Chronic HF, Migraine HAs, Angina pectoris, SVT
Term
SE of B blockers
Definition
Common
Cardiovascular: Bradycardia, hypotension
CNS: fatigue, insomnia
Other: sexual dysfunction
Less common
May adversely effect cholesterol
Term
pharmacokinetics of BB
Definition
Orally active
May take several weeks of treatment to see the full effect
Propranolol (Inderal®): extensive 1st pass
Term
Cautions with BB
Definition
Asthma/COPD: bronchoconstriction (esp. with non-selective BBs)
Blockade of B2 causes bronchoconstriction
Unstable HF (may cause further decompensation)
Heart is not functioning sufficiently & adding a B-Blocker may further  cardiac function (worsening acute, unstable HF)
Peripheral vascular disease (potential for vasoconstriction)
Unopposed -stimulation due to -blockade
AV Block
Sympathetic drive may be the only factor allowing the heart to function properly if there is a atrial-ventricular block
Withdrawal: abrupt cessation of BBs may cause angina, MI, or sudden death (patients with ischemic heart disease)
Term
ACE inhibitors actions
Definition
Decrease BP by reduction of peripheral vascular resistance
Angiotensin I------>Angiotensin II
Angiotensin II: potent vasoconstriction & release of aldosterone
ACE is also responsible for the breakdown of bradykinin (bradykinin levels are increased with ACEI treatment)
Vasodilation occurs as result of lower vasoconstriction due to ↓ levels of angiotensin II and potent vasoldilating effect of ↑ bradykinin
↓ angiotensin II decreases secretion of aldosterone-- ↓ Na and water retention
Bradykinin may be involved in ACEI-associated cough
Slows progression of diabetic nephropathy
Decreases albuminuria
Prevention of cardiac remodeling after MI
Term
Uses for Ace inhibitors
Definition
HTN
Population subsets: most effective in young, Caucasian patients
Effective in African Americans when combined with a diuretic
Heart Failure (helps prevent remodeling)
Diabetic nephropathy (Esp. useful for patients with diabetes & hypertension)
Term
Uses for Ace inhibitors
Definition
HTN
Population subsets: most effective in young, Caucasian patients
Effective in African Americans when combined with a diuretic
Heart Failure (helps prevent remodeling)
Diabetic nephropathy (Esp. useful for patients with diabetes & hypertension)
Term
SE of ACE inhibitors
Definition
Dry cough
Hypotension- esp. 1st dose
Hyperkalemia- do not use w/K⁺ sparing diuretics
Angioedema- rare- may also be due to ↑ bradykinin levels
Renal failure (patients with bilateral renal stenosis)
Other: fever, rash
TERATOGENIC
Enalapril, lisinopril
Term
Angiotensin Receptors blockers actions
Definition
Block AT1 receptors (where angiotensin II binds)
Effects similar to ACE inhibitors
 BP
Vasodilation
aldosterone secretion
Do not seem to increase bradykinin levels
Losartan, Valsartan
Term
Uses for Angiotensin Receptor Blockers
Definition
Alternative to ACE inhibitors
HTN, HF, prevention of diabetic nephropathy
Term
Adverse Effects of Angiotensin Receptors blocked
Definition
Similar to ACEI
Less risk of cough & angioedema
TERATOGENIC
Term
Renin Inhibitors actions and uses
Definition
Direct inhibition of renin
HTN- works as well as ARBs, ACEI, and thiazides
Can be combined with other antihypertensive drugs
Term
SE of Renin inhibitors
Definition
Hypotension
Diarrhea
Cough
Angioedema
TERATOGENIC
Hyperkalemia
Aliskiren (Tekturna®)
Term
Actions of CCB
Definition
Block inward movement of calcium by binding to L-type Ca channels in the myocardium & smooth muscles of the peripheral vasculature
Causing vascular smooth muscle to relax
Also have intrinsic natriuretic effect and usually don’t require addition of diuretic
Term
Uses of CCB
Definition
Uses-when 1st line is contraindicated or ineffective
HTN, angina
Population subsets
African Americans with HTN respond well to CCBs
Also a good choice for patients with peripheral vascular disease, angina, & asthma
Term
actions of Non-Dihydropyridines
Definition
Act on Ca channels of vascular smooth muscle & myocardial smooth muscle
Additional actions-slow automaticity/AV nodal conduction
Verapamil-Pronounced negative inotropic effects
Diltiazem-similar to Verapamil, but less pronounced negative inotropic effects & more favorable SE profile
Term
Action is Dihydropyridines
Definition
Cause vasodilation & decreased peripheral vascular resistance
Have greater affinity for vascular calcium channels than for Ca⁺⁺ channels in heart
Most useful for hypertension, but may cause reflex sympathetic stimulation (in response to vasodilation) & end up requiring treatment with a B-blocker
Term
Drugs for dihydropyridines
Definition
Less drug interactions with other cardiac medications (including warfarin & digoxin)
Nifedipine (Adalat, Procardia®)
Amlodipine (Norvasc®)
Felodipine (Plendil®)
Isradipine (Dynacirc®)
Nicardipine (Cardene®)
Nisoldipine (Sular®)
Term
pharmokinetics of CCB
Definition
Orally active
Short t ½ (3-8 hours)
Multiple daily dosing is required on many CCBs
Sustained Release (SR) products are available that permit longer dosing intervals
Amlodipine (Norvasc®) has a longer t 1/2 (once daily dosing)
Term
SE of CCB
Definition
Constipation
esp. with verapamil
Dizziness
HA
Fatigue

Verapamil
(-) inotropic, (-) dromotropic-velocity of conduction
Avoid in CHF or AV block
Term
Actions of alpha blockers
Definition
Competitive blockade of α1-receptors
Relaxation of arterial & venous smooth muscle (peripheral vascular resistance & BP)
Cause minimal changes to cardiac output, renal blood flow and GFR
Reflex tachycardia may occur
Term
Uses for Alpha blockers
Definition
HTN
BPH
Term
SE of alpha blockers
Definition
Postural hypotension
Tachycardia (reflex)
May require treatment with a B-blocker to prevent tachycardia
Edema
Syncope (esp. with 1st dose)
Tolerance to antihypertensive effects
Prazosin (Minipress), doxazosin (Cardura), terazosin (Hytrin)
Term
uses and actions for alpha and beta blocking agents
Definition
Mainly used in heart failure
Block both α1 and β receptors
Carvedilol (Coreg) and labetaolol
Term
Centrally acting Adrenergics drug and MoA
Definition
Clonidine (Catapress®)
α2-agonist
central adrenergic outflow
Term
use for clonidine
Definition
Used 2nd line for HTN or for refractory hypertension
Does not ↓ renal blood flow or GFR—useful in HTN w/renal disease
Term
SE of clonidine
Definition
AE: dry mouth, sedation, rebound hypertension with abrupt withdrawal
Term
Methyldopa actions
Definition
α2-agonist (also  central adrenergic outflow)- ↓total peripheral resistance and ↓ BP (no change to cardiac output and blood flow to vital organs not diminished)
Term
uses of Methyldopa
Definition
Often used for hypertension in pregnancy and renal insufficiency
Term
Actions of Vasodilaters
Definition
Direct-acting smooth muscle relaxants (↓ resistance →↓BP)
Reflex stimulation of the heart may cause tachycardia
Potential to  plasma renin concentration
Often given with diuretic & B-blocker
B-blocker to help with reflex tachycardia
Diuretic to help with Na retention (from renin)
Term
Hydralazine
Definition
Arterial & venous dilation
Predominant arterial dilation
Uses: HTN, HTN in pregnancy
AE: HA, tachycardia, nausea, sweating, arrhythmia, lupus-like syndrome
Term
Minoxidil
Definition
Dilation of arterioles
Uses: severe/refractory HTN, topically to treat male-pattern baldness
AE: reflex tachycardia & fluid retention, hypertrichosis
AEs may require treatment with a BB or diuretic to offset reflex effects
Term
Hypertensive Emergency
Definition
DBP> 130mmHg constitutes a hypertensive emergency in patients with other cardiovascular risk factors
Cerebral hemorrhage, left ventricular failure, aortic stenosis
Term
Definition
Sodium Nitroprusside, Labetol, Nicardipine, fenoldopam
Term
Sodium Nitroprusside
Definition
IV: causes prompt vasodilation (arterial & venous)
Rapid metabolism (requires continuous infusion to maintain actions)
AE (mostly associated with very high doses or prolonged administration)
Cyanide ion production
Hypotension
Term
Labetol
Definition
α & B blockade
Non-selective B-blockade
Given as IV bolus or IV infusion in hypertensive emergencies
Does not cause reflex tachycardia because of B-blockade
Term
Nicardipine
Definition
Calcium Channel Blocker
Can be given as IV infusion in hypertensive emergencies
Term
Fenoldopam
Definition
Parenteral antihypertensive
Different MoA
Dopamine-1 receptor agonist
Lowers BP but maintains or increases renal perfusion
Beneficial in patients with renal insufficiency
Term
Preload of the heart
Definition
volume of blood in the heart
amount of myocardial fiber stretch that is present before contraction
Based primarily on the amount of circulating volume; the more the volume, the greater the stretch
Term
Heart Afterload
Definition
Afterload- impedence opposing ejection of blood from the ventricle
amount of resistance (pressure) the left ventricle needs to overcome to open the aortic valve and eject the stroke volume
Term
Cardiac contraction
Definition
Force of contraction is related to the concentration of free Ca
Inotropic Drugs:
↑ Ca concentration
↑ sensitivity to Ca
Sources of Ca
Outside the cell
opening of voltage sensitive Ca channels or exchange with Na
Release from sarcoplasmic reticulum & mitochondria
Removal of Ca is required for myocardial relaxation
Na/Ca exchange
Uptake of Ca by the sarcoplasmic reticulum & mitochondria
Term
Drug Classes for intervention in HF
Definition
Inhibitors of the renin-angiotensin-aldosterone system
B-blockers
Diuretics
Inotropic agents
Direct vasodilators
Aldosterone antagonists
Term
Compensatory physiology of HF
Definition
↑ Sympathetic Activity
Activation of the Renin-Angiotensin System
Myocardial Hypertrophy
Term
Management of physical activity, lifestyle and medications
Definition
Management of chronic heart failure
Moderation of physical activity
Low Na diet (< 1.5 g/day)
Treatment of comorbid conditions
Medications to help with HF
Diuretics
Renin-Angiotensin Inhibitors
Inotropic Agents
Beta-Blockers
Term
drugs that worsen Heart Failure
Definition
NSAIDs
Alcohol
Ca channel blockers
Some antiarrhythmics
Term
MoA of Ace inhibitors
Definition
Prevent formation of angiotensin II (vasoconstrictor)
Diminish rate of bradykinin inactivation
Combination of ↓ angiotensin II & more bradykinin causes vasodilation
↓ the secretion of aldosterone
Less Na & water retention (prevents the expansion of blood volume & resultant ↑ workload of heart)
Actions
↓ vascular resistance, venous tone, blood pressure
Blunt the angiotensin II-mediated effect of ↑ epinephrine & aldosterone
Term
Uses of Ace inhibitors for HF
Definition
Indications
Monotherapy: patients with mild dyspnea on exertion & no apparent signs of volume overload
Asymptomatic patients with an ejection fraction of < 35% (left ventricular dysfunction)
Patients with recent MI (initiate immediately after MI)
All stages of left ventricular failure w/ or w/o symptoms
Therapeutic Effects
Improvement in clinical signs/symptoms
Especially in patients receiving combination therapy of ACEI & diuretics or digoxin
↓ morbidity & mortality associated with HF
Also reduces arrhythmic death, MI, and CVA
Term
SE of ACE inhibitors
Definition
Hypotension & postural hypotension
Renal insufficiency
Hyperkalemia
Angioedema
Persistent dry cough
Avoid in pregnancy (teratogenic)
Term
Ace inhibitor drugs
Definition
Benzapril (Lotensin®)
Captopril (Capoten®)
Enalapril (Vasotec®)
Fosinopril (Monpril®)
Lisinopril (Zestril, Prinivil®)
Moexipril (Univasc®)
Quinapril (Accupril®)
Ramipril (Altace®)
Term
ARB's for HG moA
Definition
Competitive antagonists of angiotensin I (AT1) receptors
More complete blockade of angiotensin action
Less effect on bradykinin
Term
Uses of ARBs in HF
Definition
Used as a substitute for ACE Inhibitors
Uses
Hypertension
Substitutes for ACE inhibitors (esp. when ACEI are associated with cough &/or angioedema)
Term
SE of ARB
Definition
Hypotension & postural hypotension
Renal insufficiency
Hyperkalemia
Avoid in pregnancy (teratogenic)
Angioedema
Term
BB used for Heart failure actions
Definition
B1 blockade: ↓ HR
Also ↓ BP (often occurs in patient with HF)
Some inhibition of renin release
↓ hypertrophy, cell death, and deletrious effects of NE on cardiac muscle cells
Term
Benefits of BB in HF
Definition
Benefits in HF: improved systolic functioning and prevention of remodeling (due to activation of the sympathetic nervous system)
May even reverse some of the remodeling
Not all BBs are FDA approved for the treatment of heart failure
Term
BB's approved for HF
Definition
Carvedilol (Coreg®)
Non-selective B-blockade
Also α-blockade
Metoprolol (Lopressor®): long acting version (Toprol)
B1 selective (Cardioselective)
Term
Diuretics benefits in HF
Definition
Reduction of symptoms of volume overload
Pulmonary congestion
Peripheral edema
Orthopnea
Paroxysmal noctural dyspnea
Term
Diuretic drus in HF
Definition
Thiazides
Loose efficacy in kidney dysfunction
Hydrochlorothiazide (HCTZ)
Loop
More potent diuresis
Do not loose efficacy in the kidney dysfunction
Furosemide (Lasix®)
K-sparing/aldosterone antagonist
HF patients have ↑ aldosterone
Weak diuretic effect, but direct aldosterone antagonism
Spironolactone (Aldactone®)
Term
Direct Vasodilators
Definition
Venous Dilators
Dilation of veins
↓ cardiac preload

Venous & Arterial Dilators
Nitrates-Nitroglycerin
Isosorbide
Arterial Dilators
Dilation of arteries
↓ systemic arteriolar resistance
↓ cardiac afterload
Hydralazine
Term
Inotropic drugs actions
Definition
(+) inotropic drugs enhance cardiac muscle contractility
↑ cardiac output
MoA
↑ Cytoplasmic Ca
Term
inotropid crugs used especially dobutamine
Definition
Digitalis
Digoxin
Dobutamine (β-agonist)
Given IV
Usually used in hospitalized, acute HF patients
↑ intracellular cAMP– results in activation of protein kinase
Slow Ca channels-important site of phosphorylation by protein kinase causing increased entry into myocardial cell =↑ contraction
Term
MoA of Digitalis or (Digoxin)
Definition
Regulation of cystosolic Ca concentration
Promotes Ca entry into the cell and causes retention of Ca in the cell
↑ cardiac contractility
↑ force of contraction
Leads to ↓ in end diastolic volume
Better ejection fraction & improved circulation
Term
Uses of Digoxin
Definition
Indicated in severe left ventricular systolic dysfunction
After initiation of a ACE & diuretic
Term
Pharmokinetics
Definition
Very potent
Narrow therapeutic index
Long t ½ (36 hours)
Eliminated via kidney
Dosage adjustment required in impaired renal function
Large Vd (accumulates in muscle tissue)
Loading dose is used if rapid therapeutic effect is needed
Term
SE of Digoxin
Definition
Cardiac Effects
Arrhythmias
Slowing of AV conduction
GI Effects
Anorexia, N/V
CNS Effects
HA, fatigue, confusion, blurred vision, alteration of color perception & halos
Can kill someone with this
Term
Toxicity of Digoxin
Definition
Electrolyte abnormalities
Toxicity is enhanced by hypokalemia
May precipitate a serious arrhythmia
Most common in patients taking diuretics
Toxicity may also be worsened with other electrolyte abnormalities (hypercalcemia & hypomagnesemia)
Toxicity is more frequent in patients with renal dysfunction
Renal impairment necessitates more frequent monitoring of digoxin levels
Dosage adjustment may be necessary
Severe toxicity may result in ventricular arrhythmias
Term
what drug causes blurred vision and halows as well as color perception
Definition
Digoxin
Term
What adds to Digoxin toxity, drugs and medical conditions?
Definition
Antiarrhymics-Quinidine, Amiodarone
Verapamil
Corticosteriods
Hypothyroidism
Hypoxia
Renal failure
Myocarditis
Term
Phosphodiesterase inhibitors action and uses
Definition
Amrinone and milrinone
↑ intracellular cAMP
Long-term therapy may be associated w/increased mortality
Short term IV milrinone for refractory HF --symptomatic improvement w/no increased mortality
Term
HF treatment
Definition
Overt Heart Failure
Usually loop diuretics are initiated first to provide relief of volume overload symptoms
Angiotensin Converting Enzyme (ACE) Inhibitor
Or ARB as alternative
BB are initiated after the patient is stable on ACEI
Digoxin is added if needed
Patients who remain symptomatic despite optimal treatment regimen
Term
Treatment of Hyperlipidemias General mechanisms
Definition
Block cholesterol absorption from the diet
Directly increase the amount of cholesterol eliminated from the body
Decrease the amount of cholesterol synthesized in the body
Term
Pharmacologic Therapy
Definition
HMG-CoA Reductase Inhibitors (Statins)
Bile Acid Sequestrants
Nicotinic Acid
Fibrates
Cholesterol absorption inhibitors
Fish Oil
Term
HMG-CoA reductase inhibitors (Statins)
MoA
Definition
HMG-CoA Reductase inhibition
Inhibition of cholesterol synthesis
Lower LDL
↑ # of LDL receptors on liver cells (further decreasing the LDL in the blood)
Due to depletion of intracellular stores of cholesterol
May also ↑ HDL and ↓ TG in some pts
Term
Uses for Statins
Definition
Hypercholesterolemia
Primary & secondary prevention of CV Events
Term
Statin Drugs
Definition
Atorvastatin (Lipitor®)
Fluvastatin (Lescol®)
Lovastatin (Mevacor®)
Pravastatin (Pravachol®)
Rosuvastatin (Crestor®)
Simvastatin (Zocor®)
Term
SE of Statins
Definition
Mild/Transient-Headache, Rash, GI upset
Rare/Severe
Hepatotoxicity
May progress to liver failure (rare)
LFTs done prior to treatment & every 6-12 months
Discontinue if LFTs change significantly
Myopathy/Rhabdomyolysis
Injured muscle tissue (manifesting as muscle aches/weakness)
May progress to myositis & rhabdomyolysis: muscle destruction with possible kidney failure
If patient has muscle pain/weakness, obtain labs
Discontinue if labs indicate muscle injury
Term
Kinetics of Statins
Definition
Kinetics
Liver metabolism: CYP 450
Significant 1st pass effect
Excretion: bile, feces, urine
Term
contraindication of Statins
Definition
Teratogenic: Contraindicated in pregnancy
Term
Drug interactions of Statins
Definition
Other cholesterol meds (Fibrates & Ezetimibe): ↑ risk of myopathy
Many drug interactions due to CYP 450 metabolism
CYP 450 inhibitors/inducers
Antibiotics: (mostly macrolides), antifungals (azoles)
Amiodarone
Calcium channel blockers: Diltizem, Verapamil
Digoxin
Warfarin
Grapefruit Juice
Cyclosporine
HIV medications
Term
Nicotinic Acid (Niacin) MoA
Definition
Directly reduces the secretion of VLDL from the liver, inhibits the hepatic synthesis of cholesterol
Strongly inhibits lypolysis in adipose tissue, which is primary precursor of free fatty acids
Liver utilizes FFA as major precursor for triacylgycerol synthesis, which is required for VLDL
↓LDL (5-25%)
↓TG (20-50%)
↑ HDL (15-35%) (better than other medications)
Term
Niacin Uses
Definition
Used to increase HDL
Familial hyperlipidemias
To decrease LDL & TG
Other Effects
Increases the secretion of tissue plasminogen activator & lowers plasma fibrinogen level (may prevent thrombotic action associated with hypercholesterolemia & atherosclerosis)
Term
SE of Niacin
Definition
Flushing (esp. facial flushing) & itching
Diminishes over several weeks, may be attenuated by taking Aspirin 325 mg 30 minutes before medication
Less flushing with extended release dosage forms
Many patients find this SE intolerable
GI Upset
Hyperuricemia (gout): inhibits tubular secretion of uric acid
Increase in blood glucose
Hepatotoxicity
More likely to occur with certain fromulations of Niacin
Assess LFTs prior to treatment & periodically
Term
Bile Acid Sequestrants/Bile Acid Resins
MoA
Definition
Anion exchange resins that bind negatively charged bile acids & bile salts in the small intestine
Prevents the bile acids from returning to the liver
Lowering bile acid concentration causes cholesterol synthesis to be diverted to make more bile acids to replenish the bile acid supply
The lowering of cholesterol in the liver causes the liver to pull more cholesterol out of the blood (therefore lowering plasma LDL)
This causes an up-regulation of hepatic LDL receptors to help pull cholesterol out of the blood
Modest rise in HDL
Term
MoA of Bile Acid Sequestrants/Bile Acid Resins
Definition
Anion exchange resins that bind negatively charged bile acids & bile salts in the small intestine
Prevents the bile acids from returning to the liver
Lowering bile acid concentration causes cholesterol synthesis to be diverted to make more bile acids to replenish the bile acid supply
The lowering of cholesterol in the liver causes the liver to pull more cholesterol out of the blood (therefore lowering plasma LDL)
This causes an up-regulation of hepatic LDL receptors to help pull cholesterol out of the blood
Modest rise in HDL
Term
Uses of Bile Acid Sequestrants/Bile Acid Resins
Definition
Reduce LDL (15-30%)
Treat Type IIa and IIb familial hyperlipidemias
Term
Bile Acid Sequestrants Kinetics
Definition
Insoluble in water and very large-not absorbed or metabolically altered in the intestine
typically excreted unchanged in the feces
Term
SE of Bile Acid Sequestrants and Drug interactions
Definition
GI: constipation, gas, indigestion, nausea
May ↓ absorption of fat-soluble vitamins

Drug Interactions
May form complexes with other drugs (affecting the absorption)
Thiazides, digoxin, warfarin (coumadin), some antibiotics
To reduce the chances of forming complexes, adjust regimen timing
give other meds 1 hour before or 4 hours after bile acid sequestrant
Term
Fibric Acid Derivatives (Fibrates) MoA
Definition
Interact with receptors in liver (PPAR-alpha) to increased activity of lipoprotein lipase & increased clearance of triglyceride-rich lipoproteins
The reduction in available triglyceride-rich lipoproteins causes a decreased production of cholesterol/triglycerides
Most effective for lowering TGs, also ↑ HDL
Term
Uses of Fibric Acid Derivatives
Definition
Reduce high levels of TGs
Term
SE of Fibric Acid Derivatives
Definition
GI upset
Cholelithiasis
Increase in biliary cholesterol excretion, which may cause gallstones
Musculoskeletal
Myositis= inflammation of voluntary muscle
Pts w/renal insufficiency may be at risk
Rash
Term
Cautions and DI of Fibric Acid Derivatives
Definition
Drug Interactions
Warfarin (Coumadin®): ↑ anticoagulant effect due to protein binding
Statins: ↑ risk for myopathy
Cautions
Pregnancy/lactation
Severe hepatic or renal dysfunction
Pre-existing gallbladder disease
Term
Drugs of Fibric Acid Derivatives
Definition
Medications
Gemfibrozil (Lopid®)
Fenofibrate (Tricor®)
Prodrug
Term
Ezemtimibe (Zetia) MoA
Definition
Acts in small intestine to inhibit cholesterol absorption (both dietary and biliary)
This leads to reduction of hepatic cholesterol stores and ↑ clearance of cholesterol from blood
↓ LDL,TGs,& possibly a small increase in HDL
Term
Use of Ezetimibe
Definition
Adjunct to dietary modifications for reducing cholesterol
↓ LDL by 19%
↑ HDL by 1-4%
↓ TGs by 5-10%
As monotherapy or in combination with a statin
In combination with statin: reduction of LDL with combination of Ezetimibe + statin is greater than either drug used as monotherapy– this has not necessarily translated to decreased CV events or change in carotid-artery intima-media thickness
Term
SE of Ezetimibe
Definition
Myopathy
Rhabdomyolysis
Hepatitis
Pancreatitis
Thrombocytopenia
Caution in hepatic impairment
Unknown if harmful
Term
DI of Ezetimibe
Definition
Statins
↑ risk of liver damage, myopathy
Fibrates
↑ risk of gallstones, myopathy
Bile Acid Sequestrants
↓ absorption of Ezetimibe
Term
Fish Oil
Definition
Consuming fatty fish or fish-oil supplements is associated with a ↓risk of CHD & CHD-related death.
Fish oil may also ↓ risk of thrombotic stroke
Contains 2 beneficial components
DPA
DHA
American Heart Association recommends eating at least 2 servings per week.
Term
Lovaza/Omacor
Definition
1st preparation of omega-3 fatty acids approved by the FDA
Contains EPA & DHA
Approved as an adjunct to diet to ↓ very high levels of TGs
May ↓ TGs by 20-50%
Combination with statin produces a further decrease
Large doses may impair platelet function
Caution with anticoagulant use, bleeding disorders
Recommended dosage is 4 g/day (4 capsules)
Term
Cholestin
Definition
Dietary supplement
Lack of data (safety, efficacy)
Made from red rice yeast
Active ingredient is the same as statins
Term
Class 1 Antiarrhythmics MoA
Definition
MoA: bind to & block fast Na channels that are responsible for the rapid depolarization (phase 0) of fast-response cardiac action potentials
Same mechanism as local anesthetics
The principal effect of reducing the rate & magnitude of depolarization by blocking Na channels is a decrease in conduction velocity in non-nodal tissue
Term
effects of class 1 antiarrhytmics based on clases
Definition
Sodium-channel blockade:
IC > IA > IB
Increasing the ERP:
IA > IC > IB (decreases)
Term
Black Box Warning for Class 1
Definition
Treatment of atrial fibrillation/atrial flutter with these drugs may cause paradoxical increase in ventricular rate
Black box warning on all class IC antiarrhythmics
CAST –cardiac arrhythmia suppression trial
Found that treating with class IC drugs for asymptomatic non-life-threatening ventricular arrhythmias who had an MI more than 6 days, but less than 2 years had an excessive mortality or non-fatal cardiac arrest when compared to carefully matched placebo control group
Now recommended to reserve these drugs for life-threatening arrhythmias
Term
effect of class 1A antiarrhythmic
Definition
The direct effect of Class IA antiarrhythmic drugs on AP is modified by its anticholinergic actions
Anticholinergic effects cause an increase in sinoatrial rate and atrioventricular conduction (which may offset the direct effects of the drugs)
While IA drugs may effectively depress atrial rate during flutter, it can lead to an increase in ventricular rate because of an increase in the number of impulses conducted through the AV node (anticholinergic effect)
May require concomitant treatment with a BB or CCB to slow AV conduction.
Anticholinergic actions are most prominent at the SA & AV nodes. Different drugs within the IA subclass differ in their anticholinergic actions
Term
Use of Class 1B
Definition
Ventricular tachyarrhythmias (VT)
Term
Use of Class 1C
Definition
Supraventricular tachyarrhythmias (SVT) & ventricular tachyarrhythmias (VT)
Term
SE of class 1C
Definition
Precipitation of arrhythmias, CNS stimulation, Cardiovascular depression, Allergic reactions
Toxicity is worsened by hyperkalemia
Term
Class 2 antiarrhythmic properties of beta blockers
Definition
Beta-blockers attenuate sympathetic effects & decrease sinus rate, decrease conduction velocity (which can block re-entry mechanisms), & inhibit aberrant pacemaker activity
Term
Class 2 drugs
Definition
Propranolol (Inderal®): Non-selective B-blocker
Indicated for post-MI mortality reduction (mortality associated with post-MI arrhythmias)
Metoprolol (Lopressor®): B1-selective B-blocker
Esmolol (Breviblock®): very SHORT acting B1 selective B-blocker
Used IV for acute arrhythmias that occur in surgery or emergencies
Term
Potassium channels for antiarrhythmics, Class 3
Definition
The primary role of potassium channels in cardiac action potentials is repolarization
In non-nodal tissue APs are initiated when a cell is depolarized by an adjacent cell
This leads to rapid opening of fast Na channels & slower opening of L-type Ca channels
As these channels become inactivated, K channels open permitting K ions to leave the cell, causing repolarization of the membrane potential (phase 3)
K channels remain open until the next action potential.
Term
MoA Class 3 antiarrhythmic drugs
Definition
MoA: Bind to & block K channels that are responsible for phase 3 repolarization
Blocking these channels slows repolarization, which leads to an increase in action potential duration and an increase in the effective refractory period (ERP)
ECG changes-increased QT interval
Common effect of all Class III antiarrhythmic drugs
Term
uses of Class 3
Definition
By increasing the ERP, these drugs are very useful in suppressing tachyarrhythmias caused by reentry mechanisms
Term
SE of Class 3
Definition
Similar toxicity to Class IA drugs
Precipitation of arrhythmias
Including Torsades
Caution with other drugs that may cause QT prolongation
Some antibiotics, TCAs, antipsychotics
Term
Class 4 MoA
Definition
MoA-bind to L-type Ca channels located on the vascular smooth muscle, cardiac myocytes, & cardiac nodal tissue
In cardiac nodal tissue, L-type calcium channels play an important role in pacemaker currents & in phase 0 of action potentials
Term
antiarrhytmic properties of CCBs
Definition
Decrease conduction velocity & prolong repolarization (esp. at the AV node)
Help block re-entry mechanisms
Decrease the firing rate of aberrant pacemaker sites
Term
SE of class 4
Definition
The cardiac selective, non-dihydropyridine CCBs can cause excessive bradycardia, impaired electrical conduction (e.g., atrioventricular nodal block), & depressed contractility
Term
Cautions of CCB's (Class 4)
Definition
CCBs (especially non-dihydropyridines), should not be administered to patients being treated with a beta-blocker because beta-blockers also depress cardiac electrical and mechanical activity and therefore the addition of a CCB augments the effects of b-blockade
Term
Digoxin as Antiarrhytmic action and use
Definition
MoA: shortens the refractory period in atrial & ventricular cells, while prolonging the refractory period in the AV node
Therapeutic uses: to control the ventricular response rate in a.fib or flutter
Term
Adenosine is antiarrhythmic MoA and use as well as SE
Definition
Decreases conduction velocity, prolongs the refractory period, & decreases automaticity in the AV node
IV adenosine is the drug of choice for aborting acute supraventricular tachycardia
When given IV in large doses: slows or completely blocks conduction in the AV node
Extremely short duration of action (seconds)
Adverse effects: flushing, chest pain, hypotension
Term
Potassium as Antiarrhythmic
Definition
Depresses ectopic pacemakers but too much K can cause re-entry arrhythmias
Term
Magnesium as Antiarrhythmic
Definition
Sometimes effective in arrhythmias caused by digoxin toxicity or Torsades
Term
Antianginal drugs Nitratses MoA actions
Definition
↓ coronary vasoconstriction, ↑ perfusion by relaxing coronary arteries
Also relax veins, ↓ preload & cardiac O₂ consumption
Term
SE and Tolerance of Nitrates
Definition
HEADACHE- most common
May also cause postural hypotension, facial flushing and tachycardia
Tolerance
Develops rapidly- blood vessels become desensitized to vasodilation
Overcome by nitrate free periods (10 to 12 hours)- usually at night when demand on hear is ↓
Term
Beta blockers for Angina
Definition
↓ oxygen demands of myocardium by lowering rate and force of contraction
O₂ demand is ↓ both during exercise and at rest
↓ severity & frequency of attacks
Can be used w/nitrates to improve exercise duration & tolerance
β₁ selective drugs (metoprolol, atenolol) are preferred
Avoid β-blockers w/intrinsic sympathomimetic activity
Term
CCBs for Angina
Definition
CCBs protect cardiac tissue by inhibiting influx of Ca into cardiac and smooth muscle
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