Antianginal Drugs Lecture Notes

Flashcards covering the classification, mechanisms, and nursing implications for antianginal medications including Nitrates, Beta-Blockers, and Calcium Channel Blockers.

Angina Pectoris

Also known as "Chest Pain"; it occurs when the supply of oxygen and nutrients in the blood is insufficient to meet the demands of the heart, causing the heart muscle to "ache."

Ischemia

Poor blood supply to an organ.

Ischemic heart disease

A condition characterized by poor blood supply to the heart muscle, often caused by atherosclerosis and coronary artery disease.

Myocardial infarction

Necrosis, or death, of cardiac tissue; it can be disabling or fatal.

Chronic stable angina

Also called classic or effort angina.

Unstable angina

Also called preinfarction angina.

Vasospastic angina

Also called Prinzmetal or variant angina.

Nitrates and Nitrites Mechanism

Relaxation of smooth muscles causing vasodilation, specifically a potent dilating effect on coronary arteries, resulting in oxygen delivery to ischemic myocardial tissue.

Nitrate Forms bypassing the First-Pass Effect

Sublingual, intravenous solutions, transdermal patches, and translingual sprays.

nitroglycerin

The prototypical nitrate that comes in both rapid- and long-acting forms; oral forms have a large first-pass effect.

isosorbide dinitrate

An organic nitrate available in rapid-acting sublingual tablets and long-acting oral dosage forms.

isosorbide mononitrate

An organic nitrate used primarily as a long-acting form for angina prevention.

Nitrate Tolerance

Occurs with around-the-clock use or long-acting forms; prevented by allowing a nitrate-free period (e.g., removing transdermal patches for $8$ hours at bedtime).

Nitrate Contraindications: Erectile Dysfunction Drugs

Use of sildenafil citrate (Viagra®), tadalafil (Cialis®), or vardenafil hydrochloride (Levitra®).

$\beta$-Blockers Mechanism

Decrease heart rate and myocardial contractility to decrease myocardial oxygen demand and increase oxygen delivery; they also block the harmful effects of catecholamines after a myocardial infarction.

atenolol (Tenormin®)

A $\beta$-blocker indicated for the prophylactic treatment of angina pectoris; shown to decrease mortality when used after myocardial infarction.

metoprolol tartrate (Lopresor®, Betaloc®)

A $\beta$-blocker used for prophylactic treatment of angina and hypertension; available in oral (immediate release and long acting) and parenteral forms.

$\beta$-Blocker Caution: Bronchial Asthma

Requires cautious use because any level of blockade of $\beta_2$-receptors can promote bronchoconstriction.

Calcium Channel Blockers (CCBs) Mechanism

Cause coronary artery vasodilation and reduce heart workload to decrease myocardial oxygen demand; they also depress automaticity and conduction in the SA and AV nodes for dysrhythmias.

amlodipine besylate (Norvasc®)

The most popular calcium channel blocker of the dihydropyridine subclass; indicated for both angina and hypertension and available only for oral use.

diltiazem hydrochloride (Cardizem®, Tiazac®)

A calcium channel blocker used for angina resulting from coronary insufficiency, hypertension, atrial fibrillation, and flutter.

Significant Weight Gain Nursing Threshold

A weight gain of $1\,kg$ in $24$ hours or $2.3\,kg$ in $1$ week should be reported by the patient.

Sublingual Nitroglycerin Potency Indicators

A burning sensation indicates the drug is still potent; potency typically lasts for $3$ to $6$ months.

Nitroglycerin Storage Requirements

Stored in an airtight, dark glass bottle with a metal cap and no cotton filler to preserve potency.

Nitroglycerin Emergency Administration Protocol

Stop activity and sit/lie down; take one sublingual tablet; call 911 immediately if no relief in $5$ minutes; take a second and then a third tablet $5$ minutes apart if needed.