2 - Cardiovascular Pharmacology Flashcards
1
Q
Most potent arterial vasopressin available.
A
Vasopressin
2
Q
This class of drugs MIMIC, ENHANCE, or BLOCK the actions of acetylcholine in autonomic ganglia and skeletal muscle at nicotine’s receptors or in parasympathetic postganglionic neurons.
A
Cholinergic drugs
3
Q
Two important binding sites of acetylcholine. (2)
A
Ester
Amine
4
Q
Cholinergic agonists two types.
A
- Choline esters
2. Alkaloids
5
Q
Give the 5 choline esters
Give the 3 choline alkaloids
A
Choline esters
- Choline
- Ach
- Carbamylcholine
- Methacholine
- Bethanecol
Choline alkaloids
- Pilocarpine
- Muscarine
- Arecoline
6
Q
This drug is almost used exclusively as a provocative agent for identyfying the presence of reactive airway disease. This drug causes bronchoconstricton, increases airway secretions, and reduces peak expiratory flow rate.
A
Methacholine
7
Q
Is a choline ester that is relatively selective for the M3 receptors in the urinary and GIT. Used for the treatment of non-obstructing urinary retention.
A
Bethanecol
8
Q
Is a choline ESTER used topically to produce miosis in wide angle glaucoma.
A
Carbamylcholine
9
Q
Is an alkaloid cholinergic agonist used as a topical miotic agent to reduce IOP. This drug is also used orally to increase salivary and lacrimal gland production in patients with xerostomia.
A
Pilocarpine
10
Q
These drugs are used to treat myasthenia gravis, glaucoma and less commonly urinary or intestinal atony. They inhibit the enzyme acetylcholinesterase.
A
Cholinsterase inhibitors
11
Q
2 classes of cholinesterase inhibitors (2)
A
- Carbamoyl esters
2. Quarternary ammonium alcohols
12
Q
Examples of carbamoyl esters (cholinesterase antagonists) (3)
A
- Neostigmine
- Pyridostigmine
- Physostigmine
13
Q
Example of quartenary ammonium compound (cholinesterase inhibitor)
A
Edrophonium
14
Q
Cholinesterase inhibitor, a tertiary amine that readily crosses the BBB and inhibits the acetylcholinesterase in the central nervous system.
A
Physostigmine
15
Q
Is the ONLY clinically used organophosphate cholinesterase inhibitor, which is applied TOPICALLY for the treatment of glaucoma.
A
Ecothiophate
16
Q
What are the 3 common muscarinic antagonists?
A
- Atropine (belladonna alkaloids)
- Scopolamine (belladonna alkaloids)
- Glycopyrrolate
17
Q
Muscarinic antagonists that penetrate the BBB (2)
A
- Atropine
2. Scopolamine
18
Q
Muscarinic antagonist particularly useful as an IM premedication before midazolam.
A
Scopolamine
19
Q
What dose of atropine that is devoid of central nervous system effect?
A
<2 mg
20
Q
Dose of atropine that can decrease HR through blockade of M1 receptors
A
Less than 0.1 mg
21
Q
What comprises the signs and symptoms of atropine toxicity (5)
A
Dry as a bone Red as a beet Blind as a bat Hot as a hare Mad as a hatter
22
Q
Treatment of choice for anticholinergic syndrome
A
Physostigmine 1 or 2 mg
23
Q
Atropine toxicity
A
0.5 - 1.0 mg: Inc HR, xerostomia (dry mouth), thirst, lack of sweat, mild pupillary dilation
2-5 mg: tachycardia, palpitations, mydriasis, cycloplegia, inability to urinate or defecate
10 or greater: fever, hallucinations, coma, death
24
Q
Most common adrenoreceptor in the skeletal muscles?
A
B2
25
Methylation of norepinephrine by what enzyme converts the NE to epinpehrine in the adrenal medullary chromaffin cells.
Phenylehtanolamine N-methyltransferase
26
Catecholamines and their receptors
Epinephrine: activates a1, b1, b2
: causes vasoconstriction EXCEPT in the blood vessels supplying the SKELETAL MUSCLES
: dose dependent (0.02 ug/kg/minj stimulates B2
: higher doses (>0.1 ug/kg/min) activates a1
Norepinephrine: a1,a2, b1
Dopamine: a1, b1, DA1, DA2
Dobutamine: b1,b2,a1
: potent stimulato of b receptors with little a receptor at inf rates less than 5 ug/kg/min
: dobutamine (-) isomer stimulates a1 rceptor above t ug/kg/min
Isoproterenol: selective B agonist derived from dopamine
: reduces coronary perfusion and decease diastolic filling time
27
Drug of choice for AHA advanced cardiac life support for malignant ventricular arrhythmias, pulseless electrical activity and asystole.
Epinephrine 1 mg
28
Why is intramuscular route more preferred over inhalation in pediatric patients with severe croup?
Because rebound edema may occur as a result of relatively short half life.
29
Most often used for the treatment of refractory hypotension resulting from prnounced vasodilation.
Norepinephrine
30
Norepinephrine in combination with nitirc oxide scavenge this drug, useful for vasoplegic syndrome.
Methylene blue
31
What is the drug used to partially counteract the actions of NE on renal blood flow and may preserve renal perfusion and renal output but most likely prevent AKI.
Fenoldopam
32
Where should NE ideally be administered?
Central venous catheter to avoid tissue necrosis from extravasation.
33
Is a biochemical precursor of NE. Lower doses < 3 ug/kg/min to dilate renal, mesenteric and splenic arterial blood flow.
Moderate doses (3-8 ug/kg/min) activate which receptors?(2)
High doses (10 ug/kg/min) activate which receptor?
Dopamine
a1 and b1
a1
34
A b2 receptor agonist that is administered subcutaneously and intramuscularly.
Terbutaline
35
Is an intravenous selective DA1 receptor agonist that does not exert activity at a or b receptors
Fenoldoopam
36
This drug exerts both direct and indirect effects. Endocytosis of this drug into a1 and b1 presynaptic postganglionic nerve terminal displaces NE from the synaptic vesicles. The displaced NE is is the released to activate the corresponding postsynaptic receptors to cause vasoconstriction and increased contractility. May cross the placenta and cause fetal acidosis.
Ephedrine
37
Why is there tachyphylaxis with ephedrine?
Because presynaptic norepinephrine stores are quickly depleted.
38
a1 adrenoreceptor antagonist drugs
1. Prazosin
39
a adrenoreceptor anTagonists (3)
1. Prazosin (a1 receptor antagonist)
2. Phenoxybenzamine (non selective)
3. Phentolamine
40
Is an orally administered non-selective a receptor anTagonist that binds IRREVERSIBLY to a receptors. Synthesis of NEW receptors is required to reverse the drug’s effect.
Phenoxybenzamine
41
Drug used to normalize arterial pressure in patients with pheochromocytoma.
Phenoxybenzamine
42
Most common side effect of phenoxybenzamine is?
Orthostatic hypotension
43
Treatment of hypotension with phenoxybenzamine?
Vasopressin
44
Potent intravenous reversible non-selective a adrenoreceptor antagonist
Phentolamine
Causes reflex tachycardia
45
This a receptor antagonist may also cause arrhythmias. It also has an antihistamine and cholinergic activity.
Phentolamine
46
What condition is contraindicated with phentolamine?
Flow-limiting coronary artery stenoses
47
Is effective in treating refractory hyprtension in patients associated with clonidine withdrawal or tyramine exposure.
Phentolamine
48
This a anTagonist undergoes hepatic metabolism
Phentolamine
49
a2 adrenoreceptor aGonist (2)
1. Clonidine
| 2. Dexmedetomidine
50
Unlike other antihypertnsive medications, this drug does not affect the baroreceptor-mediated relfex control of heart rate. This may also cause HYPERGLYCEMIA because the a2 adrenoreceptor agonist inhibits insulin release.
Clonidine
51
The sedative and anxiolytic effect of clonidine are attributed to the activation of a2 adrenoreceptors in which part of the brain?
Locus coerleus
52
It is important to remember that transdermal clonidine requires how many hours after initial application to achieve therapeutic concentrations?
48 hours
53
This a agonist exerts neuroptotective effects against cerebral ischemia. Related to a direct cytoprotective effect.
Dexmedetomidine
54
This antagonist has also been shown to inhibit platelet aggregation.
B blocker
55
Is the prototypical B-BLOCKER against which all other medications of this class is compared.
Propranolol
56
3 generations of B blockers and their corresponding drugs
1. (1)
2. (3)
3. (4)
```
1st generation (non-selective): propranolol
2nd generation (b1 blocker): metoprolol, atenolol, esmolol
3rd generation: labetalol (a1 blocker), carvedilol (anti-oxidant and anti-inflammatory), bucindolol (intrinsic sympathomimetic effects, partial b1 agonist), nebivolol (produces nitric oxide)
```
57
The estimated reduction in mortality associated with use of B blockers in myocardial infarction is approximately how many %?
25%
58
Examples of topical beta blockers (2) used for glaucoma
1. Timolol
| 2. Betaxolol
59
A selective B1 blocker with metabolism via hydrolysis by red blood cell esterases resulting in elimination half life of 9 minutes.
Esmolol
60
Unlike other vasodilators, this drug produces vasodilation without triggering the baroreceptor reflex tachycardia.
Labetalol
61
Third generation b blocker that also inhibits a1 like labetalol. This drug not only suppresses production of ROS but is also a scavenger of free radicals. This drug has been efficacious in patients with heart failure.
Carvedilol
62
These drug class are structurally related enzymes that hydrolyze the cAMP and cGMP. Inhibition of cardiac PDE III alerts intracellular Ca regulation to enhance myocardial contractility without affecting catecholamine release. Inhibition of cAMP stimulates greater calcium uptake enhancing the rate and extent of relaxation.
Phophodiesterase inhibitors
63
These drugs block platelet aggregation, supress neointimal hyperplasia and attenuate proinflammatory effects. In addition, these drugs dilate native epicardial coronary arteries and arterial bypass conduits.
PDE inhibitors.
64
PDE III inhibitor drugs (2)
1. Milrinone
| 2. Inamrinone (1st used, causes profound thrombocytopenia)
65
The only currently available class of positive inotropic drugs for oral treatment for mild to moderate heart failure.
Cardiac glycoside
66
Digitalis glycoside are naturally occuring substances found in plant species called?
Foxglove
67
Most commonly prescribed digitalis glycosides? (2)
1. Digoxin
| 2. Digitoxin
68
Are nitrovasodilators that release NO through enzymatic sulfhydryl group reduction.
Nitroglycerin
69
What does nitroglycerin dilate? Arteries or venules?
Venules
| But at higher doses nitroglycerin dilates arterioles.
70
Is an ultra-short acting direct NO donor. It is a potent VENOUS and ARTERIAL vasodilator that rapidly reduces venous and arterial pressure by decreasing LV preload and afterload. It is also a first line drug for hypertensive emergency. Also useful for cardiogenic shock.
Sodium nitroprusside
71
This drug causes coronary steal. This effect occurs because it causes greater vasodilation in vessels that perfuse normal myocardium. This causes a more pronounced reflex tachycardia.
Sodium nitroprusside
72
Metabolism of this drug produces cyanide
Sodium nitroprusside
73
Is a direct vasodilator that reduces intracellular calcium concentration. This pronounced tachycardia might produce acute MI in patients with critical coronary stenoses. This drug is commonly used for management of sustained hypertension in the absence of tachycardia.
Hydralazine
74
Myocardial and sm cell membranes contain two types of voltage-dependent Ca channels. (2)
1. T (transient)
| 2. L (long)
75
This CA type channel is the predominant target of Ca channel blockers.
L-type
76
The Ca channel blockers may be divided into 4 chemical groups (4)
1. Dihidropyridines (used clinically)
2. Benzothiazepines (used clinically)
3. Phenylalkylamines (used clinically)
4. Diarylaminopropylamine ethers
77
ALL Ca channel blockers produce greater relaxation of this blood vessel compared with other blood vessels.
Arterial
78
This drug is a direct epicardial coronary vasodilator. Its more specific indication is variant angina, a disease process in which reductions in coronary blood flow occur as a result of regional coronary vasoconstrictor independent of coronary artery stenoses. It is also used to provide arterial vasodilation in patients with Raynauds phenomenon.
Nifedipine
79
Similar to nifedipine but longer half life. Preferentially dilates arteriolar vessels. It does not depress myocardial contractility or affect SA node firing. Causes tachycardia but less effect. Used for SUSTAINED perioperative hypertension not acute.
Nicardipine
80
Ultra-short acting dihydropyridine with a plasma half-life of 2 mins after IV administration. Causes dose related arterial vasodilation while sparing VENOUS vasomotor tone, not affecting LV preload. Does not cause rebound hypertension and tachyphylaxis.
Clevidipine
81
What metabolizes clevidpine?
Plasma and tissue esterases.
82
This dihydropyridine is more lipophilic and easily crosses the BBB. Exerts more cerebral vasodilation. ONLY drug approved for cerebral vasospasm after SAH. Its only action is to reduce cerebral arteriolar resistance and enhance blood flow NOT affect incidence of recurrent hemorrhage.
Nimodipine
83
Is the ONLY benzothiazepine in current clinical use. In contrast to dihydropyridine, it exerts potent negative chronotropic and dromotropic effects. This drug may prevent subsequent MI. Prolongs AV conduction.
Diltiazem
84
This phenylalkylamine produces less arterial vasodilation but exerts more effects on automaticity, conduction and myocardial contractility than dihydropyridines. Has the potential to markedly worsen pre-existing LV systolic dysfunction because of its depressant effects. May be effective in patients with MI and angina who tolerate B1 antagonists. Also a useful alternative for adenosine for treatment of SVT.
Verapamil
85
Contraindication of verapamil?
Re-entrant SVT.
86
Use of verapamil with this drug may cause complete heart block or profound myocardial depression.
B1 antagonist
87
1st ACE inhibitor but less used due to great advserse effects.
Captopril
88
ONLY available IV ACE inhibitor.
Enalapril
89
ONLY orally available ACE inhibitor that does not require multiple dosing.
Lisinopril
90
This drug decreases LV afterload and decrease arterial pressure. Cardiac output remains unchanged. Sympathetic NS remains unchanged. As a result, patients do not develop orthostatic hypotension unless relative hypovolemia is present. This drug halt or delay the progression of heart failure and improve the quality of life. Exerts renoprotective effects in patients with DM.
ACE inhibitors
91
Most common side effect of ACE inhibitors due to blockade of bradykinin degradation.
Dry cough
May also cause hyperkalemia in patients with CKD treated with K-sparing diuretics.
Also blocks the hypokalemic side effects of thiazide and loop diuretics.
92
A rare but life threatening adverse effect of ACE inhibitor. It usually occurs with initial dose and may require endotracheal intubation.
Angioedema
93
Profound hypotension may occur with general anesthetics in patients treated with chronic ACEi. What is the best treatment for this.
V1 agonist (terlipressin)
94
This drug is commonly used in patients with HF and AMI who are unable to tolerate the effects of ACEi. This drug also reduces the risk of stroke in patients with hypertension.
ARBs
95
2 common side effects of ARBs?
Fetal toxicity
| Hyperkalemia (in patients treated with K sparing diuretics.
