Anti-Ischemic Drugs

Question 1

Stable angina
Acute cornary syndromes
Vasospastic angina

Answer 1

Epsisodes initiation by exercise and terminanted by rest….dec oxygen demand

Unstable angina, STEMI and NSTEMI…dec oxygen demand

Sudden constrictyion of coronary artery and not initiatedb y exercise or terminated by rest….inc coronary supply

Question 2

Metoprolol uses

Answer 2

Stable - drugs of choice for prophylaxis but NOT for termination

Not used for vasospastic

Most useful drugs for acute coronary syndromes

Question 3

Metoprolol effects

Answer 3

Slow HR and decrease contractility, decreasing the amount of work the heart does and thus dec oxygen demand

Question 4

Beta-blocker-how to stop

Answer 4

Prolonged beta blocker use leads to increase B receptors

If you withdraw, exaggerated response to normal levels of catecholamines…inc HR…inc anginal sx

Slowly reduce

Question 5

LT B blockers

Answer 5

Long term will improve mortality and prevent reinfarction due to both anti-ischemic and arrhytmic effects

Early IV use can be benefeical or hazrsdous

Question 6

IMmediate use of metoprolol

Answer 6

Prevented reinfarctions and arrhythmias but inc risk of cardiogenic shock

Question 7

Organic nitrates and how uses

Answer 7

Nitroglycerin and isosorbide dinitrate

Stable angina and vaosspastic - DOC for termination…alternative choice for prophylaxis due to nitrate tolerance

Acute coronary syndromes - rapid sx relief of ischemic pain…manage HTN Pulm edema, etc.

Relax most types of smooth muscle

Question 8

Mech of nitrates

Answer 8

Dec in cardiac preload due to venous vasodilation

Stable angina - dilation of large veins…slow return of blood to heart…less blood to pump….dec cardiac work and O2 demand…relief of ischemia

Vasospastic - relax coronary vasospasm and inc oxygen supply

Question 9

Nitrate metabolism

Answer 9

Must be converted in mitochondria to NO by ALDH

Then NO stimulates production of cGMP

Question 10

Nitroglycerin vs. isosorbide clearance

Answer 10

NG - 2-5 minute half life…good for termination and prophylaxis requires ER products

Isosorbide - about 1 hour half life…better oral bioavailabiluty and easier to make prophylaxis…active metaoblite also has T1/2 of 6 hrs

Differ in rate of metaboiism and thus duration of action…NO has short duration bc of rapid metab…other metab more slowly

Question 11

Dosing of NG and isosorbide

Answer 11

NG - sublingual, IV…rapid

Iso - Oral or Oral-ER

Tolerance occurs when smooth muscle can’t convert nitrates to NO…become less effective in prophylaxis…tolerance more in IV NG….can be reversed by giving pts nitrate free periods each day

Question 12

Adverse effects of nitrates

Answer 12

HA - cerebral vasodilation…avoid in pre-exisintg inc ICP

Tachy - reflec sympathetic response

Hypotension - shoudl sit when taking rapidly acting

Dec BP and preload cna be risky in some MI patients

Question 13

Nitrate contraindication - MAJOR

Answer 13

Sildenafil and other phosphodiesterase inhibs which normaly would metab cGMP…excessive elevation of cGMP which can lead to fatal vasodilation and hypOtension

Question 14

CCB uses

Answer 14

Stable angina - good for prophylaixs if can’t tolerate B blockers

Vasospastic - best choice

Question 15

Mech of CCBs

Answer 15

Vasospastic - CCBs relax vasospasm and inc oxygen supply

Stable - vsodoilation makes it easer for heart to pump blood through arteries 9dec afterload) which dec cardiac demand

Question 16

CCbs side effects

Answer 16

Hypotension, edema, HA, reflex tachycarida

DHPs(nifedipineand amlodipin) - gingival overgrowth

Question 17

Forms of CCBs and tachy/synmmpathetic tone

Answer 17

Imediate acting - common SEs

ER - incommon due to delayed, lower peak conc, and less severe

Diltiazaem and verapamil - uncommon due to their direct neg chonotropic effects

Question 18

Favored drugsd for anginal prophylaxis and combos to aviod

Answer 18

B block plus nitrate or CCB - prevents reflex tachycardia from vasodilation

Avoid - any combo of B blockers, verapamil or dilatiazem

Alo multiple vasodilators (CCBs and nitrate) for hypotension

Question 19

Termination of stable or vasospatic espidoes

Answer 19

Fast acting organic nitrates

Question 20

Prophylaxis of stable angina

Answer 20

DOC - B blocker
Secondary - CCB
Tertiary - longer-acting organic nitrates

Question 21

Prophylaxis of vasospastic angina

Answer 21

DOC - CCB

Secondary - longer acting organic nitrates

Question 22

Acute coronary syndromes

Answer 22

Fast acting nitrate - immediate isch relief

B-blocker - prevention of infarction and death