Unit 5: Cardiovascular Drugs Flashcards
The PARASYMPATHETIC portion of the autonomic nervous system is primarily
ADRENERGIC or CHOLINERGIC?
CHOLINERGIC
The SYMPATHETIC portion of the autonomic nervous system is primarily
ADRENERGIC or CHOLINERGIC?
ADRENERGIC
When alpha-1 adrenergic receptors are stimulated, what results? (Think: cardiovascular)
VASOCONSTRICTION
When alpha-2 adrenergic receptors are stimulated, what results?
Affect postsynaptic nerve terminals (nerve itself) —> affects neurotransmitter release —> STIMULATES CNS
When beta-1 adrenergic receptors are stimulated, what is the primary result?
Cardiac stimulation: INCREASED HEART RATE
When beta-2 adrenergic receptors are stimulated, what is the primary result?
DILATION/RELAXATION of SMOOTH MUSCLE:
—decreased BP
—bronchodilation
—glycogenolysis —> increase in serum glucose
What do SNS Agonists do?
— Stimulate BETA-1: increase contractility, increase heart rate
— Stimulate BETA-2: vasodilation
— Stimulate ALPHA-1: vasoconstriction
Name 4 SNS AGONISTS used in the ACUTE setting:
- Dopamine
- Dobutamine
- Epinephrine
- Norepinephrine
What is DOPAMINE, and what does it do?
— SNS Agonist to DOPAMINE receptors
— effects are DOSE-DEPENDENT
— LOW DOSE: renal and coronary vasodilation, stimulates BETA-1 in the heart which increases heart rate and cardiac output
— HIGH DOSE: more ALPHA stimulation —> VASOCONSTRICTION
What is DOBUTAMINE, and what does it do?
— adrenergic AGONIST
— stimulates BETA-2
— stimulates BETA-1 to increase contractility
— TX: cardiogenic shock and severe heart failure
What is EPINEPHRINE, and what does it do?
- SNS agonist with preference for BETA-1
- - increases contractility and heart rate
What is NOREPINEPHRINE, and what does it do?
- SNS agonist with preference for ALPHA receptors
- - increases vasoconstriction and blood pressure
RISKS of SNS agonists
- stimulation of adrenergic system can PRECIPITATE ARRHYTHMIAS d/t tachycardia
- tachycardia can lead to DECREASED CARDIAC OUTPUT
- ISCHEMIA AND TISSUE DAMAGE due to vasoconstriction:
- – coronary arteries –> ischemia
- – splanchnic circulation –> ischemia
- – peripheral vessels –> decreased circulation to hands and feet –> tissue damage
Define splanchnic circulation
gut circulation
Name drugs with SNS agonist effects (but are not SNS agonists)
milrinone
vasopressin
What is MILRINONE, and what does it do?
phosphodiesterase inhibitor
increases contractility
vasodilation
good for beta blocker overdoses
What is VASOPRESSIN, and what does it do?
vasopressor
contracts smooth muscles
no effect on heart rate or contractility because it does not work on the CNS
improvement in BP due to vasoconstriction
What is DIGOXIN, and what does it do?
inhibits Na/K pump –> improves contractility to slow heart rate
USED in heart failure to improve symptoms; but DOES NOT improve mortality
ADVERSE EFFECTS of DIGOXIN
brady arrhythmias, especially if K+ is too low
ANTIDOTE to DIGOXIN
DIGIBIND
When is DIGIBIND used?
For life-threatening dysrhythmias/overdose due to/of digoxin
What is MIDODRINE, and what is it used for?
oral pressor
metabolized in body; active metabolite is an ALPHA-1 agonist
TX: orthostatic hypotension
What is FLUDROCORTISONE, and what is it used for?
synthetic corticosteroid
increases blood volume due to increased sodium and water retention
TX: orthostatic hypotension
What do ALPHA-1 BLOCKERS do to the CV SYSTEM?
vasodilation via peripheral arterioles
Name 4 ALPHA-1 BLOCKERS
- terazosin
- prazosin
- doxazosin
- tamsulosin
What is key to remember about the ALPHA-1 BLOCKERS?
1st dose precipitous hypotension –> use low 1st dose
How do the ALPHA-2 AGONISTS work?
vasodilation
ALPHA-2 stimulates CNS –> inhibits NE release –> inhibits vasoconstriction –> VASODILATION
Name 2 ALPHA-2 AGONISTS
- clonidine
2. methyldopa
What is clonidine used for?
- hypertension
2. relaxation
METHYLDOPA is rarely used; what do we use it for, and what is unique about it?
hypertension
one of the rare BP meds that are okay to use in pregnancy
What beta blocker is good for heart failure as it also has an alpha-blocking effect?
carvedilol
Name 7 beta blockers
- metoprolol
- labetalol
- atenolol
- bisoprolol
- esmolol
- carvedilol
- nebivolol
What beta blocker is nonselective, but selective at very low doses?
nebivolol
What beta blocker is good for aortic dissection because it cuts down on the shear force?
labetalol
What beta blockers also have alpha blocking effects?
labetalol
carvedilol
What to watch for with beta blockers?
BRONCOCONSTRICTION due to blocking of beta-2, especially in asthmatics
(BETA-2 agonism causes broncodilation)
BRADYCARDIA
HYPOTENSION
Why do we often prefer selective beta blockers?
less likely to block beta-2 and cause issues for asthmatics
What can happen with abrupt withdrawal of beta blockers?
hypertension
tachycardia
When can rebound hypertension or tachycardia (from beta blocker withdrawal) cause ANGINA or MI?
in a patient with CAD
What can happen with beta blockers and cholesterol?
elevated LDL; low HDL (difficult to manage cholesterol when on a beta blocker)
What kinds of drugs have effects similar to beta blockers?
vasodilators and calcium channel blockers
Name 4 vasodilators
nitroprusside (IV)
nitroglycerin (IV, SL, PO, patch)
hydralazine (IV, PO)
minoxidil (PO)
What to watch for with nitroprusside?
cyanide toxicity
What vasodilator is okay for use in pregnancy?
hydralazine
What side effect do we watch for with minoxidil use?
HYPERTRICHOSIS (abnormal amount of hair growth)
Name the 2 categories of calcium channel blockers
- dihydropyridines
2. nondihydropyridines
What to watch for with calcium channel blockers?
bradyarrhythmias
hypotension
Why is calcium important in the cardiac system?
Need it for muscle contraction
How do the calcium channel blockers work?
prevent calcium from entering cells –> decrease vascular smooth muscle contraction
DECREASE CARDIAC CONTRACTILITY
DECREASE CARDIAC CONDUCTION RATE
What drug category is helpful for large vessel stiffness in older adults?
calcium channel blockers
Name 4 dihydropyridine calcium channel blockers
- amlodipine
- nifedipine
- nimodipine
- nicardipine
name a phenylalkylamine nondihydropyridine calcium channel blocker
verapamil
name a benzothiazepine nondihydropyridine calcium channel blocker
Diltiazem
What adverse effect should we monitor for with amlodipine use?
peripheral edema (patients d/n like it)
What is RENIN?
renin is released when kidneys believe blood volume is low
What does renin do?
stimulates release of ANGIOTENSIN 1 from the liver
What is the difference between ANGIOTENSIN 1 and ANGIOTENSIN 2?
ANGIOTENSIN 1 is inactive
ACE converts ANGIOTENSIN 1 to ANGIOTENSIN 2
ANGIOTENSIN 2 is a potent vasoconstrictor
What does ANGIOTENSIN 2 do?
a potent vasoconstrictor which increases blood pressure
stimulates pituitary to release ADH
stimulates adrenals to release ALDOSTERONE
What does Aldosterone do?
Aldosterone stimulates reabsorption of sodium and water to increase blood volume and excretion of potassium
Name 6 ACE Inhibitors
- lisinopril
- enalapril
- captopril (shortest acting)
- quinapril
- fosinopril
- benazepril
What to watch for with ACE inhibitors
renal failure
hyperkalemia
creatinine tends to bump up, but not by a ton
cough (troublesome, but not usually dangerous)
ANGIOEDEMA
What causes ANGIOEDEMA with ACE Inhibitors?
decreased breakdown of bradykinin (probably also causes cough)
What do ACE Inhibitors tend to end with?
“-PRIL”
What do ARBs tend to end with?
-SARTAN”
What is an ARB? What does it do?
Angiotensin II Receptor Blocker
after angiotensin II is produced, it blocks receptor sites
Name 5 ARBs
- losartan
- candesartan
- valsartan
- olmesartan
- telmesartin
ARBs tend to have less hyperkalemia; why?
they do not affect aldosterone
Why do we not tend to use direct renin inhibitors?
they are new
brand name
expensive
not any more effective than ACE-Is or ARBs
What are aldosterone receptor antagonists also known as?
potassium sparing diuretics
Name 2 potassium sparing diuretics
- spironolactone
2. eplerenone
Eplerenone is newer and more expensive. What is the advantage of eplerenone over spironolactone?
no gynecomastia
What to watch for with potassium sparing diuretics like spironolactone?
hyperkalemia
gynecomastia
What to watch for with diuretics?
hypokalemia electrolyte imbalance dysrhythmias fluid imbalance renal failure due to removing too much fluid
Name 2 diuretics that work on the proximal convoluted tubule. What are these diuretics called?
- mannitol
- acetazolamide
“OSMOTIC DIURETICS”
Name 2 diuretics that work on the ascending limb of the Loop of Henle. What are these diuretics called?
- furosemide
- bumetanide
“LOOP DIURETICS”
Name 2 diuretics that work on the distal convoluted tubule. What are these diuretics called?
- hydrochlorothiazide
- metolazone
“THIAZIDE DIURETICS”
Name 2 diuretics that work just past the distal convoluted tubule. What are these diuretics called?
- spironolactone
- triamterene
“POTASSIUM SPARING DIURETICS”
What to watch for with thiazide diuretics like HCTZ?
AGRANULOCYTOSIS
- -extreme leukopenia
- -fever
- -ulcerations of mucous membranes
For whom are thiazide diuretics contraindicated?
people with a sulfa allergy
Which diuretic is very potent when given in combination with Loop diuretics? How is it given?
Metolazone
give 15-30 minutes prior to loop diuretic dose
Why are thiazide diuretics weaker?
the decrease reabsorption of water, sodium, bicarbonate, and chloride; BUT most sodium has already been reabsorbed by this point
What to beware of with Loop diuretics?
agranulocytosis
SJS
What is AGRANULOCYTOSIS?
- -extreme leukopenia
- -fever
- -ulcerations of mucous membranes
For whom are loop diuretics contraindicated?
people with sulfa allergies
pregnant women
How do osmotic diuretics work?
produce rapid diuresis by increasing the solute load (osmotic pressure) of glomerular filtrate –> inhibits reabsorption of water
increased osmotic pressure causes water to be pulled from extravascular sites
What to remember for Bronchospastic Airway Disease?
avoid beta blockers with active symptoms also taking long-acting beta agonists
if necessary, choose a cardioselective agent
What to remember for pregnant patients?
avoid ACE-I/ARB in 3rd trimester (teratogenic)
ok for HTN: methyldopa, hydralazine
What to remember for PVD?
beta blockers can worsen symptoms of claudication
What to remember for renal insufficiency?
avoid potassium-sparing diuretics and aldosterone antagonists (as these patients probably already have difficulty clearing potassium)
What to remember with gout?
diuretics can aggravate/initiate a gout flare
What to remember in patients who have experienced angioedema?
avoid ACE-I and ARB
What classes of drugs are used to treat heart failure?
- ACE-I or ARB (if intolerant, use hydralazine plus nitrate)
- Beta Blockers
- aldosterone antagonist
- digoxin
- diuretic (only if needed to maintain fluid balance)
For heart failure treatment, what beta blockers to use?
FIRST CHOICE: carvedilol (added vasodilation effect); use the highest dose pt will tolerate (not great for rate control)
NEXT CHOICE: metoprolol succinate 200mg (1st choice if rate control also needed
According to JNC8 guidelines, what are the targets for blood pressure management?
60+ <150/90
<60 <140/90
If a patient has CKD, to manage hypertension, what drug class should be chosen first?
ACE-I or ARB
In the black population, what are the preferred drug classes for managing hypertension?
thiazide diuretic or CCB
What drug classes are used to manage CAD/Angina?
nitrates
beta blockers
CCBs (dihydropyridines)
What are the long-acting nitrates?
isosorbide-dinitrate
isosorbide-mononitrate
