Drugs for Angina Pectoris

Question 1

two goals of angina drug therapy:

Answer 1

́ Prevention of myocardial infarction and death

́ Prevention of myocardial ischemia and anginal pain

Question 2

Three families of antianginal agents

Answer 2

́ Organic nitrates
 ́ Nitroglycerin  ́ Beta blockers
 ́ Example: Metoprolol
 ́ Calcium channel blockers
 ́ Example: Verapamil  ́ Ranolazine
 ́ Newer drug with limited indications  ́ Can be combined with other drugs

Question 3

Antiischemic Therapy

Answer 3

́ Nitroglycerin: Three doses sublingually every 5 minutes (tablet or spray), followed by IV therapy if persistent ischemia or hypertension occurs
́ Beta blocker: Give first dose IV if chest pain is ongoing
́ Supplemental O2
́ IV morphine
́ Angiotensin-converting enzyme (ACE) inhibitor

Question 4

Antiplatelet/Anticoagulant Therapy

Answer 4

́ Aspirin (indefinitely)
́ Clopidogrel [Plavix]
́ Abciximab [ReoPro]
́ Eptifibatide [Integrilin] or tirofiban [Aggrastat]
́ Anticoagulant therapy
́ Subcutaneous LMW heparin [Lovenox]), direct thrombin inhibitors (bivalirudin [Angiomax]), factor Xa inhibitors (fondaparinux [Arixtra]), or IV unfractionated heparin

Question 5

́ Nitroglycerin

Answer 5

́ Stable and variant angina
́ Vasodilator
́ Acts directly on vascular smooth muscle (VSM) to promote vasodilation
́ Adverse effects ́ Headache
́ Orthostatic hypotension ́ Reflex tachycardia

˜ Mechanism of antianginal effects
˜ Decreases cardiac oxygen demand

́ Drug interactions
́ Hypotensive drugs
́ Phosphodiesterase type 5 inhibitors
́ Beta blockers, verapamil, and diltiazem

́ Tolerance
́ Can develop rapidly
́ Cross-tolerance to all other nitrates
́ To minimize, use the lowest effective dose
́ Long-acting formulas: 8 drug-free hours per day

́ Preparations and routes of administration ́ Sublingual tablets
́ Sustained-release oral capsules
́ Transdermal delivery systems
́ Translingual spray ́ Topical ointment ́ IV infusion

́ Long-acting preparations ́ Discontinue slowly
́ Therapeutic uses
́ Acute anginal therapy
́ Sustained anginal therapy
́ IV for perioperative control of blood pressure and treatment of heart failure with myocardial infarction (MI), unstable angina, and uncontrolled exacerbations of chronic angina

Question 6

Isosorbide mononitrate and isosorbide dinitrate

Answer 6

́ Actions identical to those of nitroglycerin

́ Used for angina; taken orally; produce headache, hypotension, and reflex tachycardia

Question 7

Propranolol, metoprolol

Answer 7

́ Adverse effects  ́ Bradycardia
 ́ Decreased atrioventricular (AV) conduction  ́ Reduction of contractility
 ́ Asthmatic effects
 ́ Use with caution in patients with diabetes
 ́ Insomnia
 ́ Depression
 ́ Bizarre dreams
 ́ Sexual dysfunction

Question 8

Verapamil, diltiazem, nifedipine

Answer 8

Calcium Channel Blockers

 ́ Block calcium channels in vascular smooth muscle  ́ Used for stable and variant angina
 ́ Adverse effects
 ́ Dilation of peripheral arterioles  ́ Reflex tachycardia
 ́ Hypotension
 ́ Beta blockers
 ́ Bradycardia
 ́ Heart failure
 ́ AV block

Question 9

Ranolazine

Answer 9

́ Belongs to first new class of antianginal agents approved in more than 25 years
́ Benefits are modest and greater in men than in women
́ Does not reduce heart rate, blood pressure, or vascular resistance
́ Can prolong QT interval; multiple drug interactions
́ Exact mechanism unknown
́ Not a first-line therapy; combine with first-line agents for inadequate response to other first-line medications