Antianginal

Question 1

What are the 4 classes of antianginal drugs?

Answer 1

1. Nitrates
2. B-blockers
3. Calcium Channel Blockers
4. Sodium Channel Blockers

Question 2

Nitrates

Answer 2

Isosorbide Dinitrate, Isosorbide Mononitrate, Nitroglycerin, Sodium Nitroprusside

MOA: mimic effects of endogenous NO

CE: vasodilation (mainly venous), decrease preload and afterload which decreases cardiac workload and increase oxygen supply

CA: Isosorbide Dinitrate/Mononitrates prophylaxis of stable, unstable, and Prinzmetals angina; Nitroglycerin acute Tx/prophylasis of stable, unstable, and Prinzmetals angina; Sodium Nitroprusside severe HTN emergencies and heart failure

AE: Isosorbide Dinitrate/Mononitrate, Nitroglycerin postural hypotension, facial flushing, reflex tachycardia; Sodium Nitroprusside severe nausea, vomiting, headaches, cyanide intoxication

TCo: Sildenafil

Question 3

Beta-Blockers

Answer 3

Propanolol (B1/2), Metoprolol (B1), Atenolol (B1)

MOA: negative inotropic and chronotropic agents

CE: reduction in heart rate and contractility to decrease cardiac workload

CA: stable and unstable angina

AE: bradycardia, arrhythmias, bronchoconstriction (propranolol), fatigue, CNS effects

TCo: Prinzmetals angina, asthma, COPD

Question 4

Calcium Channel Blockers

Answer 4

Nifedipine, Amlodipine; Diltiazem, Verapamil

MOA: Inhibit vascular L-type Ca²⁺channels; inhibit vascular and cardial L-type Ca²⁺ channels

CE: coronary and peripheral vasodilation > increase O₂ supply; coronary and peripheral vasodilation and reduction in HR and contractility > decrease cardiac worklaod and increase O₂ supply

CA: stable, unstable angina as substitute of B-blockers and relieve symptoms of Prinzmetals angina

AE: reflex tachycardia, peripheral edema, hypotension, gingival hyperplasia, fatigue, flushing; constipation, negative inotropic effects

TCo: nondihydropyridine B-blockers, 2nd/3rd degree heart block, or severe left ventricular dysfunction, uses cautiously with digoxin

Question 5

Sodium Channel Blockers

Answer 5

Ranolazine

MOA: blocks Na⁺ current that facilitates Ca²⁺ entry via Na⁺/Ca²⁺ exchanger

CE: myocardial relaxation leading to decreased cardial workload

CA: angina pts who have failure other therapies

AE: QT prolongation, nausea, constipation, dizziness