Heart Failure Meds and Anticoagulants

Heart Failure Medications and Anticoagulants

Brent Evans, MSN, RN, CNE

Heart Failure Overview

  • Definition: Inability of heart to meet circulatory needs.

    • Compensatory mechanisms increase cardiac output (CO).

    • Over time, weakened heart is unable to maintain CO.

    • Compensation can exacerbate heart failure (HF).

    • Fluid backs up, leading to decreased oxygenation of tissues.

    • Decreased quality of heart pump results in tachycardia, further decreasing CO and increasing myocardial oxygen demand.

Causes of Heart Failure

  • Coronary Artery Disease: Most common cause, often leading to myocardial infraction (MI).

  • Hypertension: Contributes significantly to HF.

  • Valvular Disease: Affects heart function.

  • Cardiomyopathy: Disease of heart muscle leading to heart failure.

Signs and Symptoms of Heart Failure

Left-Sided Heart Failure

  • Orthopnea: Difficulty breathing when lying flat.

  • Anxiety: Secondary to shortness of breath (SHOB).

  • Tachycardia: Increased heart rate to compensate.

  • Weak Pulses: Indicating decreased cardiac output.

  • Cough: Fluid backing up into lungs.

Right-Sided Heart Failure

  • Jugular Venous Distension (JVD): Observed when not lying flat.

  • Hepatomegaly: Liver enlargement due to fluid back-up.

  • Edema: Fluid retention in body tissues.

  • Nocturia: Increased urination at night due to fluid dynamics.

  • Exertional Dyspnea: Shortness of breath on exertion.

Drug Treatment for Heart Failure

  • Primary goal: Reduce workload on heart and/or improve heart's ability to increase output.

Drug Classes

  • Beta Blockers:

    • Reduce heart rate and force of contractions.

    • Examples: Metoprolol, Atenolol, Propranolol.

    • Block beta-1 receptors, leading to decreased heart workload.

    • Monitor heart rate (HR) and blood pressure (BP) before administration.

  • ACE Inhibitors:

    • Examples: Lisinopril, Captopril.

    • Block angiotensin II to reduce afterload and decrease cardiac remodeling.

    • Monitor BP before administration.

  • Diuretics:

    • Reduce fluid overload and improve symptoms (covered separately).

  • Digoxin:

    • Cardiac glycoside that increases force of contraction (positive inotrope) and decreases heart rate (negative chronotrope).

    • Parameters: Check apical pulse for 60 seconds before administration.

    • Narrow therapeutic range (0.5-0.8 ng/mL).

    • Monitor for toxicity: dysrhythmias, nausea, visual disturbances, etc.

Newer Medications

  • Dobutamine: A beta-1 agonist, improving cardiac output and lowering BP.

  • Milrinone: A phosphodiesterase inhibitor, enhancing cardiac function and decreasing afterload.

  • Ivabradine: An HCN blocker that lowers heart rate without affecting contractility.

  • SGLT2 Inhibitors (e.g., Dapagliflozin): Promote fluid and sugar excretion.

Assessing Heart Failure Drug Therapy

  • Monitor:

    • Heart Rate (HR) and Blood Pressure (BP)

    • Level of consciousness (LOC)

    • Exertion tolerance

    • Urine output (UOP)

    • Capillary refill and peripheral pulses

    • Lung sounds and daily weights

    • Electrolytes and Brain Natriuretic Peptide (BNP) levels

    • Improved functional status.

Anticoagulants Overview

  • Antiplatelets:

    • Examples: Aspirin, Clopidogrel (Plavix).

    • Stop platelets from aggregating; used primarily for arterial clots.

    • Often prescribed in dual therapy.

  • Thrombolytics:

    • Examples: Urokinase, Alteplase.

    • Used to dissolve existing clots; high risk of bleeding.

  • Anticoagulants:

    • Indicated for prevention of blood clots, e.g., in DVT, PE, atrial fibrillation.

    • Treatment involves parenteral drugs like heparin.

Heparin

  • Administered subcutaneously or intravenously.

  • Monitor Partial Thromboplastin Time (PTT), aiming for specific therapeutic ranges.

  • Risk of complications, including bleeding and thrombocytopenia.

Low Molecular Weight Heparin (LMWH)

  • Example: Enoxaparin (Lovenox).

  • More expensive, longer half-life, and can be given at home post-surgery.

Warfarin

  • Oral anticoagulant, requiring monitoring of INR (ideal range typically 2-3).

    • Many drug interactions, vitamin K is essential in management.

Newer Oral Anticoagulants

  • Apixaban, Dabigatran have more rapid onset and less monitoring requirements.

Important Considerations

  • Patient Monitoring:

    • Signs of active bleeding or upcoming invasive procedures are critical.

    • Contextualize anticoagulation therapy in relation to patient’s overall health and treatment plan.

Additional Resources

  • Heart Failure readings: Pages 211-241 for background; pages 255-256 for nursing process; pages 265-271 for digoxin and nitrates; pages 288-302 for anticoagulants.

Questions?

robot