Pharmacology: Katzung Drugs used in the treatment of Angina

Question 1

What are the two basic strategies used in angina treatment?

Answer 1

(1) Reduction of the mycocardial oxygen demand

(2) Increase in myocardial oxygen delivery.

Question 2

What is the major determinant of myocardial oxygen requirement?

Answer 2

Myocardial fiber tension

Question 3

What two factors determine diastolic filling pressure (Preload) and what controls them?

Answer 3

(1) blood volume (fluid retention)

2) venous tone (sympathetic outflow

Question 4

What two factors determine afterload (systolic pressure)?

Answer 4

(1) areterial pressure

(2) large artery stiffness

Question 5

To what class of drugs do Nitroglycerin SL, and isosorbide dinitrate SL belong to?

Answer 5

Nitroglycerin and isosorbide are short acting nitrates

Question 6

What is the MOA for nitroglycerin and isosorbide?

Answer 6

They release NO thus increasing cGMP and relaxing smooth muscle particularly in vascular smooth muscle.

Question 7

What are the clinical applications for nitroglycerin and isosorbide?

Answer 7

(1) Acute angina pectoris

(2) acute coronary syndrome

Question 8

What toxicities are associated with nitroglycerin and isosorbide?

Answer 8

(1) Tachycardia
(2) orthostatic hypotension
(3) headache

Question 9

What differentiates isosorbide from nitroglycerin?

Answer 9

Isosorbide is longer acting (20-30 min) than nitroglycerin (1-15 min)

Question 10

To what class of drugs do oral nitroglycerin, oral isosorbide dinitrate, and oral isosorbide mononitrate belong to?

Answer 10

They are intermediate acting nitrates

Question 11

What is the MOA of oral nitroglycerin, oral isosorbide dinitrate, and oral isosorbide mononitrate?

Answer 11

They release NO and mediate vascular smooth muscle relaxation.

Question 12

What is the clinical application for oral nitroglycerin, oral isosorbide dinitrate, and oral isosorbide mononitrate?

Answer 12

prophylaxis of angina

Question 13

What toxicities are associated with oral nitroglycerin, oral isosorbide dinitrate, and oral isosorbide mononitrate?

Answer 13

(1) tachycardia
(2) Orthostatic hypotension
(3) Headache

Question 14

What is transdermal nitroglycerin used for?

Answer 14

transdermal nitroglycerin is a long acting nitrate used in the prophylaxis of angina.

Question 15

What is amyl nitrite?

Answer 15

it is an ultra short acting nitrite that is inhaled as a vapor. it has a duration of action of 1-5 min. It is obsolete for medical purposes but is sometimes used for recreation.

Question 16

What are the cardiovascular effects of the nitrates?

Answer 16

They reduce myocardial oxygen demand by reducing cardiac output through reduced venous return to the heart (decreased preload). Nitrate reduced blood pressure may cause reflex tachycardia.

Question 17

What drug-drug interactions are important to consider when giving nitrates?

Answer 17

Nitrates interact with sildenafil and similar drugs used for erectile dysfunction. They inhibit PDE5 which metabolizes cGMP in smooth muscle. These drugs will synergize with nitrates to cause dangerous hypotension.

Question 18

Which calcium channel blockers are used in the treatment of angina pectoris?

Answer 18

Verpamil, Diltiazem, Nifedipine, Amlopidine, Felodipine, nicardipine, nisoldipine,

Question 19

What is the MOA for verpamil and diltiazem?

Answer 19

The block L-type Ca channels in smooth muscle and heart. This decreases intracellular Ca and decreases the force and rate of contraction.

Question 20

What are the clinical uses for Verpamil and diltiazem?

Answer 20

(1) Stable atherosclerotic Angina
(2) Vasopsastic prinzmetal angina
(3) hypertension
(4) Nodal arrythmias
(5) migraine

Question 21

What are the adverse effects that are associated with verpamil and diltiazem?

Answer 21

(1) Constipation
(2) pre tibial edema
(3) Flushing
(4) dizziness
(5) Cardiac depression (higher doses)
(6) Hypotension (higher doses)

Question 22

What is the mechanism of action for nifedipine, amlopidine, felodipine, nicardipine, and nisoldipine?

Answer 22

They are dihydropyridine Ca channel blockers that have more vascular than cardiac effect.

Question 23

What are the clinical applications for nifedipine, amlopidine, felodipine, nicardipine, and nisoldipine?

Answer 23

(1) angina

(2) hypertension

Question 24

What are the adverse effects associated with nifedipine, amlopidine, felodipine, nicardipine, and nisoldipine?

Answer 24

(1) Constipation (less than verpamil)
(2) pre tibial edema
(3) Flushing
(4) dizziness
(5) Cardiac depression (higher doses) (less than verpamil)(May actually cause reflex tachycardia)
(6) Hypotension (higher doses)

Question 25

What beta blockers are used to treat angina?

Answer 25

propranolol, Atenolol, metoprolol, et al.

Question 26

What is the MOA for the beta blockers in the treatment of Angina?

Answer 26

They block sympathetic effects on the heart and blood pressure while reducing renin release.

Question 27

What are the clinical applications for propranolol?

Answer 27

(1) angina
(2) hypertension
(3) migraine
(4) performance anxiety

Question 28

What differentiates the other beta blockers from propranolol?

Answer 28

Propranolol has a shorter duration of action than the other beta blockers.

Question 29

What class of drugs are ranolazine and trimetazidine?

Answer 29

They are partial fatty acid oxidation inhibitors (pFOX inhibitors). They block late Na+ current in mycocardium and reduce cardiac work

Question 30

What are the clinical applications for ranolazine and trimetazidine?

Answer 30

(1) Angina

Question 31

What is the MOA of ivabradine?

Answer 31

Ivabradine blocks the pacemaker Na+ If current in the sinoatrial node, thus selectively reducing heart rate.

Question 32

What are the clinical applications for ivabradine?

Answer 32

Investigational

(1) angina
(2) heart failure.