Pharm Exam 3 Vasodilators & Ca+ Channel Blockers

Front 1

nitric oxide (NO) therapeutic use?

Back 1

Primary pulmonary hypertension / Acute respiratory distress syndrome
(Inhaled)

Front 2

nitroglycerin therapeutic use?

Back 2

*Effort angina: tx & prophylaxis
*Unstable angina
*MI
(For all of above: symptom relief but no change in survival)
*Variant (vasospastic) angina
*CHF

Front 3

isosorbide dinitrate therapeutic use?

Back 3

*Effort angina: tx & prophylaxis
*Unstable angina
*MI
(For all of above: symptom relief but no change in survival)
*Variant (vasospastic) angina
*CHF

Front 4

isosorbide mononitrate therapeutic uses?

Back 4

*Effort angina: tx & prophylaxis
*Unstable angina
*MI
(For all of above: symptom relief but no change in survival)
*Variant (vasospastic) angina
*CHF

Front 5

Nitroprusside thereaputic use?

Back 5

1. Hypertensive emergencies
2. Acute exacerbation of CHF
3. For controlled hypotension in surgery
4. Post MI to decrease oxygen consumption (off label)

Front 6

Sildenafil therapeutic use?

Back 6

a) erectile dysfunction
b) Pulmonary hypertension

Front 7

amlodipine therapeutic use?

Back 7

Angina
Prophylaxis--pts with angiographically documented Coronary Artery Disease without heart failure

*diabetic neuropathy
*Raynaud's syndrome

Front 8

nifedipine therapeutic use

Back 8

Angina
Hypertension

*Raynaud's syndrome
*diabetic neuropathy

Front 9

diltiazem therapeutic use?

Back 9

Angina
Arrythmias (rate control in afib, short- & long-term tx of PSVT)
Hypertension
Prophylaxis--pts with angiographically documented CAD without heart failure


*Migraine
*Raynaud's syndrome
*Diabetic nephropathy

Front 10

verapamil therapeutic use?

Back 10

*Arrhythmias (rate control in afib, short- & long-term tx of PSVT)
*Hypertrophic cardiomyopathy
*Migraine
*DOC for vasospastic angina
*diabetic neurapathy

Front 11

hydralazine therapeutic use?

Back 11

*Hypertension in mid- to late-pregnancy, hypertensive emergencies in pregnancy

*CHF in black pts only: used w/ isosorbide dinitrate

*3rd line choice in heart failure pts who can't tolerate ACEI or ARB; may be added to ACEI + beta blocker regimen in pts not adequately controlled

Front 12

minoxidil uses

Back 12

*Hair growth (topical)

*Severe chronic hypertension refractory to other tx (use w/ diuretic & beta blocker)

Front 13

Nitroglyercerine MOA?

Back 13

These drugs release NO or an NO-like substance which in turn activates a cytoplasmi guanylyl cyclase thus increasing intracellular cGMP and leading to smooth muscle relaxation

They are not dependent on endogenous NO and NOS. They can vasodilate even in the absence of intact vascular endothelium!

Front 14

Nitroglycerine - more venous or arteriole effect? What does this result in?

Back 14

Venous vasodilation > arterial

result:
decrease in systolic and diastolic BP w/ reduced CO --> dizziness, pallor, sympathetic reflexes

For endocardial vessels, flow increases because of the reduction in end diastolic ventricular pressure

Net effect of nitroglycerin is reduce oxygen demand on myocardia!

Front 15

Nitroprusside MOA?

Back 15

nitrovasodilator, that releases NO rapidly

mechanism not understood

Front 16

Nitroprusside - more venous or arteriole effect? What does this result in?

Back 16

1) Nitroprusside dilates both arterioles and venules

2)both lowers TPR and venous return

Patients Normal L. Ventricular fxn: Decreased CO

Patients w/ low L.Ventric Fxn: increased CO (b/c of afterload reduction)

Front 17

What drugs have tolerance?

Back 17

Organic nitrate vasodilators

Front 18

Sildenafil MOA?

Back 18

elective inhibitors of phosphodiesterase 5, the main phosphodiesterase in corpus cavernosum. This increases the half-life of cGMP formed in response to NO, thus enhancing NO’s vasodilating effects.

Front 19

nifedipine MOA?

Back 19

Block Ca L channels by binding α1 subunit → ↓ probability that channel will open in depolarization

Front 20

Nifedipine & amlodipine effects?

Back 20

↓ BP w/o affecting cardiac conduction/ contractility (b/c no use-dependent block, & at doses high enough to affect heart, profound arterial dilation → sympathetic drive compensation) → ↑CO & ↑HR


Coronary vasodilation ↑↑↑
Peripheral vasodilation ↑↑↑
Myocardial contractility ↔
Cardiac output ↑↑
Resting Heart Rate ↑
AV conduction ↔

Front 21

diltiazem moa?

Back 21

*Use-dependent (rate-dependent) cardiac block
*Slows AV node conduction (↑PR interval)
*Negative inotropic, dromotropic, & chromotropic

Front 22

Diltiazem effects?

Back 22

Coronary vasodilation ↑↑
Peripheral vasodilation ↑↑
Myocardial contractility ↔ or ↓
Cardiac output ↑↓
Resting Heart Rate ↔ or ↓
AV conduction ↓

Front 23

Verapamil MOA?

Back 23

Use-dependent (rate-dependent) cardiac block

*Slows AV node conduction (↑PR interval)


Decrease the probability that a channel will open at any given level of depolarization.

Can also block Na+ at high dose

Front 24

Verapamil effect?

Back 24

Coronary vasodilation ↑↑
Peripheral vasodilation ↑↑
Myocardial contractility ↓
Cardiac output ↑↓
Resting Heart Rate ↔ or ↓
AV conduction ↓

Overall:in patients without decreased left ventricular function CO may actually improve, but in patients with CHF, who are already generally under high sympathetic tone, CO may decrease.

Front 25

Hydralazine effects?

Back 25

Selectively dilates ARTERIOLES & associated w/ powerful sympathetic baroreceptor reflex --> increased HR, ionotropic action, and renin + salt retention

Front 26

Hydralazine side effects

Back 26

HIGH PROBABILITY OF CORONARY STEAL IN PATIENTS W/ CAD!!!

Front 27

Minoxidil MOA

Back 27

Prodrug → metabolized by hepatic sulfotransferase to minoxidil N-O sulfate → opens ATP-modulated K channel → hyperpolarization →
↓ voltage-dependent Ca entry → induces relaxation → arterial vasodilation → sympathetic baroreceptor reflex → ↑ cardiac rate & contractility & CO

Front 28

MINOXIDIL pharm effects

Back 28

arterial vasodilator which induces sympathetic baroreceptor reflexes that increase cardiac rate and contractility. --> marked increase in CO due to increased venous return

Front 29

Minoxidil side effects

Back 29

*↑ renin production → ↑ salt & water retention (control w/ diuretics)
*Sympathetic reflex → ↑ cardiac O2 demand → myocardial ischemia (control w/ beta-blockers)
*In pts w/ LV hypertrophy, ↑ venous return → pulmonary hypertension
*Flattened & inverted T waves (b/c opened cardiac K channels → shortened action potential duration)
*Hypertrichosis (ie, too much hair!)

Front 30

Side effects of diltiazem and verapamil?

Back 30

*Bradycardia
*CHF exacerbation
*AV block
*CI in SA or AV nodal disturbances, ventricular dysfunction (increases risk of converting vtach to vfib), heart failure
*Drug interactions: inhibit CYP3A4