Beta Blockers and Vasodilators Flashcards
Two water soluble BB’s? What is unique about their pharmacokinetics?
- Atenolol, nadolol
- long half-lives
- metabolized by the kidney
How is esmolol metabolized?
plasma esterases (10 min half life)
Where are B2 receptors found?
vascular and bronchial smooth muscle
Which generation of BB’s is non-selective and vasodilatory?
3rd
Two ways 3rd gen BB’s assert vasodilation and associated drugs?
- direct via NO (carvedilol, nebivolol)
- indirect via alpha blockade (carvedilol, labetalol)
7 functions of carvedilol?
- non-selective BB
- alpha blocker
- calcium blocker
- NO
- anti-oxidant
- anti-proliferative
- blocks expression of genes involved in myocardial damage
Four classes of oral meds proven in RCT’s to reduce CV M&M?
- BB’s
- ACEI’s
- statins
- anti-platelets
3 typical functions of the B1 blockade?
- neg inotropism
- neg chronotropsim
- blocked renin secretion (regulated by B1R)
Two typical AE’s specific to non-selective BB’s?
- bronchoconstriction
- exacerbation of PVD
Three typical AE’s associated with all BB’s?
- sedation, fatigue, mental impairment
- hypotension and bradycardia
- inc tri’s and dec HDL
What 5 conditions can BB’s be used to treat?
- HF
- post-MI
- SVT
- ischemic HD
- HTN
Why should BB’s be used with cautious in diabetic patients?
- catecholamines utilize B2R to promote glycogenolysis and mobilize Glc
- block of this receptor may induce or exacerbate hypoglycemia (and mask tacky associated with hypoglycemia)
6 contraindications for BB Tx?
- severe brady
- high grade AVB
- cardiogenic shock (LVF)
- severe bronchospasm
- severe depression
- symptomatic PVD
In HF, what state should you make sure the patient is in before Rx’ing BB’s?
hemodynamically stable
What molecule does eNOS used to make NO?
L-arginine –> citrulline + NO
How are lipid soluble BB’s metabolized?
- hepatic – first-pass effect and variable bioavailability
- shorter 1/2 life but distributed in the fat
- cross BBB – CNS effects
Which BB has intrinsic sympathomimetic activity?
Pindolol (used in anxiety)
What two BB’s possess alpha blocking activity?
- carvedilol
- labetalol
Which BB is good to used in bad ED cases and why?
Nebivolol because it potentiates NO (inc L-arginine)
Name two classic, non-selective 1st gen BB’s:
- nadolol
- propranolol
Name three B1 selective, 2nd gen BB’s:
- atenolol
- esmolol
- metoprolol
Name two non-selective BB’s with additional actions (3rd gen):
- carvedilol
- labetalol
Name one B1 selective BB with additional actions (3rd gen):
- nebivolol (NO potentiation)
B1 selective BB’s? = MANE
metoprolol, atenolol, nebivolol, esmolol
Which two lipid-soluble BB’s are metabolize by CYP2D6?
metoprolol and carvedilol
Which non-selective BB has an extremely long half life?
nadolol (water soluble) - 24 hours
What two drug classes are recommended for all patients with prior MI?
BB’s and ACEI’s
What are two calcium channel blockers than act on the vasculature only?
amiodipine and nifedipine
What are two venous selective vasodilators?
isosorbide dinitrate, nitroglycerin = organic nitrates
What group of vasodilators block hypertrophic growth responses?
RAAS interfering drugs - aliskerin, lisinopril, losartan
What are two indications for CCB tx? Additional indication with non-dihydropyridine CCB’s?
- ischemic HD, HTN
- SVT (nodal)
What are two organic nitrates that are metabolized to NO?
nitroglycerin and isosorbide dinitrate
Primary indication for use of organic nitrates?
ischemic HD (some use in HF)
Why does nitroglycerin have such a short half-life? Indication?
- hepatic metabolism (can be lengthened by creams, patches to avoid first-pass effect)
- rapid relief of angina pectoris
NG vs. isosorbide dinitrate?
ID has a longer plasma half life and can additionally be used to Tx HF
Which vasodilator contains CN?
sodium nitroprusside
Two main indications for balanced vasodilator (short half-life) drug sodium nitroprusside?
- rapid reduction of BP in HTN crisis
- rapid decrease in preload and after load due to venous and arterial effects –> effective in Tx decompensated CHF
Mechanism of action and target vessels of Minoxidil?
- arterial vasodilator
- stimulates an outward K+ channel resulting in hyper polarization of vascular smooth muscle cell
What is Minoxidil reserved for? Novel indication?
- Tx of moderate to severe HTN
- hair growth = Rogaine
What are two balanced vasodilators?
Terazosin (alpha antagonist) and sodium nitroprusside (organic nitrate)
What vessels are relaxed by hydralazine? Two uses of the drug?
- arteries
- second line anti-HTN
- HF in combination with isosorbide dinitrate (dec in pre-load AND after-load with combination - very strong response in African Americans)
What enzyme is inhibited by milrinone?
PDE3 in heart and BV’s
Outcome of inhibition of cardiac PDE vs. vascular smooth muscle PDE?
- increased force of contraction and cardiac output = positive isotropism (inc calcium etc)
- vasodilation
