PHARM: THE CARDIOVASCULAR SYSTEM

angiotensin converting enzyme inhibitors (ACEs): -pril

INDICATED: HTN, CHF—blocks conversion of angiotensin I to angiotensin II, increasing renin and decreasing aldosterone leading to vasodilation

• can cause dry cough (indicative of angioedema), and should be D/C if does

• monitor BP

• contraindicated in pregnancy

• increases K; AVOID K sparing meds (e.x spironolactone)

• AVOID in pt. taking lithium\

• nephrotoxic

angiotensin II receptor blockers (ARBs): -sartan

INDICATED: HTN, DM, neuropathy, CHF—inhibits vasoconstrictive properties of angiotensin II

• monitor BP, fluid lvls, and renal (BUN/Cr) and liver (AST/ALT) status

• increases K

• contraindicated in pregnancy

calcium channel blockers (CCB) ACTION ON HEART & BLOOD VESSELS: verapamil, diltiazem

act like valium for the heart

INDICATED: HTN, angina, dysrhythmias (afib/aflutter)—blocks calcium channels in the heart and blood vessels causing decreased blood pressure and increasing coronary perfusion, slowing the HR, slowing AV node conduction and decreasing the force of contraction

• constipation—increase dietary fiber/fluid intake

• dizziness, facial flushing, HA, edema in ankles and feet

• enhances cardiac suppression of digoxin and BB; monitor closely if given together

  • AVOID in HF d/t cardiac suppression

  • AVOID in AV block d/t slowing of AV node conduction

• toxicity can be tx with glucagon

calcium channel blockers (CCB) ACTION ON ONLY BLOOD VESSELS: -dipine

INDICATED: HTN, angina—blocks calcium channels in the blood vessels causing vasodilation; decreasing BP and increasing coronary perfusion

• dizziness, facial flushing, HA, edema of ankles and feet

• gingival hyperplasia

• reflex tachycardia—can combine with BB

• preferable for HF or AV block

• interacts with grapefruit juice

• toxicity can be tx with glucagon

venodilators: ARTERIAL: hydralazine, minoxidil

INDICATED: HTN, HTN crisis, HF—relaxes arterial smooth muscle to promote dilation; decreasing afterload and increasing cardiac output (CO)

• reflex tachycardia—combine with BB

• hypotension can trigger volume expansion—combine with diuretic

• long term use can cause systemic lupus erythematosus (SLE)—D/C

• increased fall risk

venodilators: VENOUS & ARTERIAL: nitrates

INDICATED: HTN, HTN crisis, angina—venous dilation decreases preload=decreased ventricular contraction=decreased workload for the heart, arterial dilation decreases afterload=increased CO

• HA (expected), dizziness, flushing, orthostatic hypotension=increased fall risk

• rotate sites of nitro paste, can be applied anywhere on clean, dry, intact, hairless skin

• patches should be removed overnight for 10-12 hours to prevent tolerance

• patches are used to prevent, SL tablets are used to alleviate acute attacks; q5min, max of 3 tablets

anticholinergic & antiarrhythmic: atropine

INDICATED: sinus bradycardia, heart block, excessive secretions—inhibition of acetylcholine; increasing HR, bronchodilation, and decreased secretions

• monitor for urinary retention and constipation d/t anticholinergic effects

• avoid in clients with glaucoma d/t increased IOP

class I sodium channel blockers: procainamide, lidocaine

INDICATED: arrhythmias—block sodium channels, decreasing impulse conduction and delaying repolarization

• diarrhea

• SLE like syndrome

• negative inotropic effects leading to hypotension and cardiac suppression

class II beta blockers: -olol

INDICATED: HTN, angina, arrhythmias, cardiomyopathy, alcohol withdrawal, & anxiety—blocks beta I and beta 2 adrenergic receptors, slowing the HR

• DO NOT D/C abruptly

• can mask s/sx of hypoglycemia—monitor BG

• CAUTION with asthma & COPD—can cause bronchospasms d/t interaction with beta 2 receptors in the lungs

class III potassium channel blockers: amiodarone, ibutilide

INDICATED: atrial fibrillation/flutter—blocks K+ channels to prevent repolarization, decreasing myocardial excitability and interfering with other excitatory pathways (beta receptors, sodium, and calcium)

• dizziness, tremors, ataxia, pulmonary fibrosis, bradycardia, heart block, blue-gray skin, disruption in thyroid (d/t containing iodine), not given in pregnancy

adenosine

INDICATED: SVT—slows conduction through AV node, interrupting re-entry pathways through AV node, restoring NSR

• there will be a period of asystole after administration

• rapid push or it will not work

• CAUTION in asthmatics

digoxin

INDICATED: HF, a.fib/flutter, CHF, cardiogenic shock—increase contractility and decrease HR by acting on sodium-potassium ATPase, making it more efficient

• DO NOT use with verapamil or diltiazem

• DO use with ARTERIAL venodilators hydralazine/minoxidil or CCB that ACT ON BLOOD VESSELS ONLY -pine in the instance of reflex tachycardia (SE of both of these meds)

• narrow therapeutic range (0.5-2 ng/mL)—monitor for toxicity

  • EARLY SIGNS: N/V, anorexia, vision changes (yellow/green halos)

  • LATE SIGNS: bradycardia

• R/F:

  • clients with hypokalemia

    • if on loop diuretic & digoxin more likely to be toxic

    • licorice extract acts like aldosterone; promotes K+ excretion

  • clients with hypomagnesemia (<1.8)

  • clients with hypercalcemia (>10.5)

  • elderly!

    • decreased renal and liver fxn; harder to clear drugs, allowing levels to build up.