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Heart Failure

2 min read

References:

  1. Course Module

Heart failure is the loss of pumping ability of the heart. It may be categorized as Left-Sided or Right-Sided Heart Failure (LSHF, RSHF). There are many causes, but in terms of physiological changes:

  • Preload is greatly reduced (e.g. hypovolemia)
  • Preload is greatly increased (e.g. hypervolemia, pancytopenia)
  • Afterload is obstructed or difficult (e.g. valvular stenosis/regurgitation, hypertension)
  • Damage to the heart muscle (e.g. cardiomyopathy, M.I.)
  • Increased metabolic states (e.g. Hyperthyroidism, Graves Disease, Pheochromocytoma)

Compensatory Mechanisms of the Heart

Once the heart reaches its physical limit, cardiac decompensation occurs.

  1. Ventricular Dilatation
  2. Ventricular Hypertrophy
  3. Sympathetic Nervous System Stimulation → Tachycardia

Manifestations

Left-Sided Heart Failure

LSHF will always be followed by RSHF if left untreated.

  • Forward Effect: Decreased Systemic Perfusion (Cerebral, Renal, Body Cells)
  • Backward Effect: Pulmonary Congestion and Edema

Right-Sided Heart Failure

  • Backward Effect: Systemic Congestion (Distended Jugular Veins, Increased CVP, Hepatosplenomegaly) and Edema (Dependent Edema, Ascites, Generalized Edema), Increased SGPT & SGOT (Impaired Liver Function), Anorexia and G.I. Distress

Assessment

  • Heart/Lung Sounds: “galloping horse”, crackles/rales (blowing into a can of soda with a straw).
  • The patient feels like they are drowning.

Diagnostic Findings

  • CXR: Cardiomegaly
  • Pleural Effusion
  • ECG: ventricular hypertrophy, dysrhythmias
  • ECHO: reveals cardiac valvular changes, pericardial effusions, chamber enlargement, and ventricular hypertrophy.

Medical Management

  1. Low Na+ Diet and Fluid Restrictions
  2. Inotropic Agents: Increased contractility, slows heart rate and conduction.
    • Digoxin (Lanoxin): the mainstay treatment for HF.
      • Also decreases sympathetic activity and increases parasympathetic activity.
      • Always check for digitalis toxicity (0.5 to 2 ng/mL), the main presenting symptom of which is bradycardia, along with anorexia, N&V, rapid, slow, irregular heart rate, and disturbance in color vision.
      • Antidote: Digibind
      • Do not administer if assessment is found to be <60 BPM and supplement potassium if patient is hypokalemic.
    • Dopamine (Intropin), Dobutamine (Dobutrex)
  3. Diuretics: Furosemide (Lasix), Chlorothiazide (Diuril)
    • Inhibition loss of sodium means potassium is exchanged and excreted in turn. A serum test is done prior to usage of Furosemide, and supplementation is ordered if hypokalemic. Hypokalemia also contributes to digitalis toxicity due to its direct effect on cardiac contraction.
  4. Vasodilators: Nitroglycerin
  5. ACE Inhibitors: “-pril”s

Nursing Management

Most clients manage chronic heart failure at home.

  • Administer prescriptions and evaluate effect.
  • Promote positive cardiac output.
  • Monitor for excess fluid volume (weight gain) and electrolyte imbalances (potassium)
  • Promote oxygenation and balance activity according to tolerance.

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