Cardiovascular Medications and Treatment Overview

Considerations for Patient Education on Antihypertensives

ACE Inhibitors

• Mechanism of Action:

  • Enzyme responsible for converting Angiotensin I (AI) to Angiotensin II (AII).
  • AII is a potent vasoconstrictor that also stimulates aldosterone secretion (which increases sodium and water resorption).

• Indications:

  • Hypertension (HTN).
  • Heart failure.
  • Diabetics with neuropathy.

• Contraindications:

  • Known Drug Allergy (KDA) especially reactions leading to angioedema.
  • Baseline potassium (K+) levels of 5 mEq/L or higher.
  • Pregnant or lactating women.
  • Children.
  • Patients with bilateral renal artery stenosis.

• Adverse Effects:

  • Fatigue, dizziness, mood changes, headaches.
  • Dry, nonproductive cough.
  • Loss of taste.
  • Hyperkalemia.
  • Angioedema.
  • Renal impairment or acute renal failure (ARF).

• Black Box Warning:

  • Fetal toxicity; advised against use in pregnancy.

• Common ACE Inhibitors:

  • Benazepril (Lotensin), Captopril (Capoten), Enalapril (Vasotec), Fosinopril (Monopril), Lisinopril (Prinivil or Zestril), Moexipril (Univasc), Perindopril (Aceon), Quinapril (Accupril), Ramipril (Altace), Trandolapril (Mavik).

• Monitoring:

  • Blood pressure (BP), pulse, weight, intake/output (I/Os).
  • Use caution in older patients and those with renal dysfunction.
  • Contact healthcare provider (HCP) immediately if angioedema occurs.
  • Discuss potential impairment of taste and avoidance of potassium supplements.

Beta Blockers

• Mechanism of Action:

  • Block sympathetic nervous system stimulation by competing with epinephrine and norepinephrine.
  • Can be cardioselective (blocking beta1 receptors on heart) or nonselective (blocking both beta1 and beta2-adrenergic receptors).

• Indications:

  • Angina, myocardial infarction (MI), cardiac dysrhythmias.
  • Hypertension, heart failure.

• Contraindications:

  • Uncompensated heart failure.
  • Cardiogenic shock, heart block, or bradycardia.
  • Pregnancy.
  • Severe pulmonary disease; Raynaud's disease.

• Adverse Effects:

  • Bradycardia, atrioventricular (AV) block, impotence.
  • Constipation, nausea/vomiting, fatigue, depression.
  • Delayed recovery from hypoglycemia.
  • Major effects if abruptly stopped could precipitate MI and rebound hypertension.

• Black Box Warning:

  • Do not withdraw abruptly.

• Common Beta Blockers:

  • Acebutolol (Sectral), Atenolol (Tenormin), Betaxolol (Kerlone), Bisoprolol (Zebeta), Carvedilol (Coreg), Esmolol (Brevibloc), Labetalol (Trandate), Metoprolol (Lopressor), Nadolol (Corgard), Nebivolol (Bystolic), Pindolol (Visken), Propranolol (Inderal).

• Monitoring:

  • BP, pulse, weight, I/Os, blood glucose levels if diabetic.
  • Pulse: count apically for 1 full minute.
  • BP: take in supine and standing positions.

• Patient Instructions:

  • Patients must not stop medications abruptly due to rebound hypertension.
  • Inform about potential for sexual dysfunction.
  • Instruct to monitor daily weights, BP, and heart rate.
  • Advise avoiding sudden position changes; intake of fluids and fiber; low-fat diet, moderate exercise, and stress management.

Angiotensin II Receptor Blockers (ARBs)

• Mechanism of Action:

  • Similar to ACE inhibitors, block the binding of AII to Type 1 AII receptors.
  • Block vasoconstriction and secretion of aldosterone; do not cause cough as ACE inhibitors do.

• Indications:

  • Heart failure, hypertension.

• Contraindications:

  • Pregnant or lactating women.

• Common ARBs:

  • Losartan (Cozaar), Eprosartan (Teveten), Valsartan (Diovan), Irbesartan (Avapro), Candesartan (Atacand), Olmesartan (Benicar), Telmisartan (Micardis), Azilsartan (Edarbi).

• Adverse Effects:

  • Chest pain, fatigue, weakness, hypoglycemia, diarrhea, anemia, urinary tract infections.

• Black Box Warning:

  • Fetal toxicity; avoid in pregnancy.

• Interactions:

  • Potassium (K+) supplements and potassium-sparing diuretics (can cause hyperkalemia), NSAIDs, Lithium, Rifampin.

Calcium Channel Blockers (CCBs)

• Mechanism of Action:

  • Prevent calcium from assisting in contraction of heart muscle, relaxing smooth muscles, and dilating arteries.

• Indications:

  • Angina, hypertension, supraventricular tachycardia (as antidysrhythmic).

• Contraindications:

  • Acute myocardial infarction, 2nd- or 3rd-degree AV block, hypotension.

• Common CCBs:

  • Diltiazem (Cardizem), Amlodipine (Norvasc), Felodipine (Plendil), Isradipine (DynaCirc), Nicardipine (Cardene), Nifedipine (Adalat), Nimodipine.

• Adverse Effects:

  • Hypotension, palpitations, tachycardia or bradycardia, constipation, nausea, dyspnea, rash, flushing, peripheral edema.

• Interactions:

  • Grapefruit juice, beta blockers, digoxin, azole antifungals, statins, clarithromycin, erythromycin, HIV drugs, cyclosporine, amiodarone.

• Monitoring:

  • BP, pulse, weight, I/Os.
  • Patient instructions similar to beta blockers.

Vasodilators

• Mechanism of Action:

  • Act directly on arterioles and/or venous smooth muscle, leading to vasodilation, thus reducing systemic vascular resistance (SVR).

• Indications:

  • Hypertension, acute myocardial infarction (MI), coronary artery disease (CAD).

• Contraindications:

  • Hypotension, cerebral edema, head injury, heart failure secondary to diastolic dysfunction.

• Common Vasodilators:

  • Diazoxide, Hydralazine, Minoxidil, Nitroprusside.

• Adverse Effects:

  • Dizziness, headache, anxiety, tachycardia, edema, dyspnea, nausea/vomiting, diarrhea, hepatitis, systemic lupus erythematosus (SLE) risk, vitamin B6 deficiency, rash.

• Black Box Warning:

  • Nitroprusside: risk of severe hypotension and cyanide toxicity.

Loop Diuretics

• Mechanism of Action:

  • Inhibit chloride (Cl-) and sodium (Na+) reabsorption in the loop of Henle, leading to fluid loss.
  • Help in dilating blood vessels and reducing SVR.

• Indications:

  • Edema associated with heart failure, hepatic or renal disease, hypertension.

• Contraindications:

  • Severe electrolyte loss, hypersensitivity, anuria, severe renal failure.

• Common Loop Diuretics:

  • Bumetanide, Ethacrynic acid, Furosemide (Lasix), Torsemide.

• Adverse Effects:

  • Dizziness, headaches, tinnitus, blurred vision, nausea, diarrhea, hypokalemia, and potential severe electrolyte depletion.

• Monitoring:

  • Daily weight, BP, pulse, hydration status, electrolytes.

Potassium-Sparing Diuretics

• Mechanism of Action:

  • Interfere with sodium-potassium exchange in the collecting ducts and distal convoluted tubules; spironolactone binds to aldosterone receptors preventing sodium and water resorption.

• Indications:

  • Hypertension, hyperaldosteronism; used to counteract potassium loss from loop and thiazide diuretics.

• Contraindications:

  • Severe renal failure or anuria, severe hepatic failure.

• Common Potassium-Sparing Diuretics:

  • Amiloride, Spironolactone (Aldactone), Triamterene.

• Adverse Effects:

  • Gynecomastia (spironolactone), metabolic alkalosis, hyperkalemia, dizziness, headache, cramps, nausea, diarrhea.

• Black Box Warning:

  • Spironolactone: potential tumorigenic with long-term use.

Thiazide Diuretics

• Mechanism of Action:

  • Inhibit sodium (Na+), potassium (K-), and chloride (Cl-) reabsorption in the distal convoluted tubule leading to osmotic water loss.

• Indications:

  • Hypertension, edema, diabetes insipidus, idiopathic hypocalciuria.

• Contraindications:

  • Anuria, severe renal failure, hepatic coma.

• Common Thiazide Diuretics:

  • Hydrochlorothiazide (HCTZ), Chlorothiazide, Chlorthalidone, Indapamide, Metolazone.

• Adverse Effects:

  • Dizziness, headache, blurred vision, gastrointestinal disturbances.

Cardiac Glycosides

• Mechanism of Action:

  • Inhibit sodium-potassium ATPase pump, increasing sodium and calcium concentrations leading to enhanced myocardial contractility.

• Indications:

  • Systolic heart failure, atrial fibrillation, heart block, heart failure from diastolic dysfunction.

• Contraindications:

  • 2nd- or 3rd-degree heart block, ventricular fibrillation.

• Common Cardiac Glycosides:

  • Digoxin (Lanoxin).

• Adverse Effects:

  • Bradycardia, hypotension, confusion, visual disturbances, nausea.

• Monitoring:

  • Monitor serum electrolytes, especially potassium and magnesium levels; assess pulse rate before administration; cautious with IV administration.

• Antidote:

  • Digoxin immune Fab (parenterally).

Antidysrhythmics

• Mechanism of Action:

  • Correct abnormal cardiac electrophysiological function by varying effects such as delaying or accelerating repolarization, increasing or decreasing action potentials, blocking sympathetic stimulation to the heart, and inhibiting calcium channels.

• Indications:

  • Various cardiac dysrhythmias including Atrial fibrillation, ventricular tachycardia, long-QT syndrome.

• Common Antidysrhythmics:

  • Quinidine, Disopyramide, Procainamide, Lidocaine, Amiodarone, Sotalol, Dofetilide, Dronedarone.

• Adverse Effects:

  • May produce new dysrhythmias, headaches, mixed gastrointestinal symptoms, and possible proarrhythmic effects.

• Monitoring:

  • Continuous BP and pulse monitoring, EKG for prolonged QT intervals, and immediate reporting of unusual symptoms (angina, hypotension, etc.).

• Interactions:

  • Warfarin (especially with amiodarone), digoxin, and various other drugs.

• Patient Education:

  • Inform patients to take oral medications with food, monitor for cardiovascular responses, and avoid stopping medications abruptly.