Deja review Cardio/Renal agents - Antianginal agents

Question 1

Define angina pectoris

Answer 1

Chest pain resulting from a myocardial oxygen demand that is not met by adequate oxygen supply, seen in patient with myocardial ischemia

Question 2

What type of angina is caused by spontaneous coronary vasospasm?

Answer 2

Prinzmetal (variant) angina

Question 3

What type of angina is caused by atherosclerosis of coronary vessels and is precipitated by exertion?

Answer 3

Classic angina

Question 4

What type of angina can be acute in onset and is caused by platelet aggregation?

Answer 4

Unstable angina

Question 5

What 2 mechanistic strategies are used in treatment of angina?

Answer 5

1) INC oxygen supply to the myocardium

2) DEC myocardial oxygen demand

Question 6

What types of drugs can INC oxygen supply?

Answer 6

Nitrates, calcium channel blockers (CCBs)

Question 7

What types of drugs can DEC oxygen demand?

Answer 7

Nitrates, CCBs, ß-blockers

Question 8

What is the drug of choice for immediate relief of anginal symptoms?

Answer 8

Sublingual nitroglycerin (NTG)

Question 9

What is MOA of nitrates?

Answer 9

Nitrates form nitrites, nitrites form nitric oxide (NO), NO activates guanylyl cyclase to INC cGMP, INC cGMP leads to INC relaxation of smooth muscle

Question 10

How does cGMP lead to relaxation of vascular smooth muscle?

Answer 10

Causes dephosphorylation of myosin light chains

Question 11

How do nitrates INC oxygen supply?

Answer 11

Dilation of coronary vessels which leads to INC blood supply

Question 12

How do nitrates DEC oxygen demand?

Answer 12

Dilation of large veins which leads to preload reduction, DEC preload reduces the amount of work done by the heart, DEC amount of work results in DEC myocardial oxygen requirement

Question 13

What are the adverse effects of nitrates?

Answer 13

Headache, hypotension, reflex tachycardia, facial flushing, metnemoglobinemia

Question 14

Why must patients have at least a 10-12 hour “nitrate free” interval every day?

Answer 14

Tolerance (tachyphylaxis) develops to nitrates if given on a continous (around the clock) basis

Question 15

Nitrates are contraindicated in patients taking any of what 3 medications?

Answer 15

1) Sildenafil
2) Vardenafil
3) Tadalafil

Question 16

Methemoglobin formation, specifically by amyl nitrite, can be used to treat what type of poisoning?

Answer 16

Cyanide

Question 17

What are the common formulations of nitrates?

Answer 17

NTG, isosorbide mononitrate, isosorbide dinitrate

Question 18

What is the time to peak effect of sublingual NTG?

Answer 18

2 minutes

Question 19

What is the dosing frequency of sublingual NTG during an anginal episode?

Answer 19

Every 5 minutes for a max of 3 doses

Question 20

How do ß-blockers work in the treatment of angina?

Answer 20

Inhibition of α2 adrenoceptors which leads to DEC CO, HR, and force of contraction, thus reducing the workload of the heart

Question 21

Do α-blockers INC oxygen supply?

Answer 21

NO

Question 22

For each of the following CCBs, state whether their primary effects are on the myocardium or peripheral vasculature:

• Verapamil
• Dihydropyridine (DHP, nifedipine, amlodipine, felodipine, isradipine, nicardipine)
• Diltiazem

Answer 22

• Verapamil: Myocardium (greater negative inotropic effects)
• Dihydropyridine (DHP, nifedipine, amlodipine, felodipine, isradipine, nicardipine): Peripheral vasculature (more potent vasodilators)
• Diltiazem: Myocardium

Question 23

How do CCBs work in the treatment of angina?

Answer 23

Block vascular L-type calcium channels which leads to DEC heart contractility and INC vasodilation