Cardio

• Cardiomyopathy


  Structural abnormality of the heart muscle
• Types of cardiomyopathy

  • Dilated (DCM)
  • Restrictive (RCM)
  • Hypertrophic (HCM)
• Dilated cardiomyopathy


  • Severe dilation of both ventricles without muscle hypertrophy
  • Decreased cardiac output (systolic dysfunction)
• Restrictive cardiomyopathy


  • Stiff heart muscles
  • Decreased compliance & inadequate ventricle filling (diastolic dysfunction)
• Hypertrophic cardiomyopathy


  • Left ventricular septum hypertrophy
  • Stiff, non-compliant left ventricles resulting in a decreased cardiac output
• Causes of cardiomyopathy


  • Genetic
  • Mixed (genetic, ETOH, DM, MI, ischemia)
  • Acquired (metastatic tumors, amyloidosis, chemo, radiation, autoimmune, idiopathic)
• Dilated cardiomyopathy treatment


  1. Prevent cardiac arrest: Implantable cardiac defibrillator (ICD) or pacer

  2. Prevent thrombosis formation: Anticoagulants (heparin, Lovenox, warfarin)

  3. Improve contractility, reduce LV filling pressure: Inotropic drugs (3Ds)

  4. Reduce preload: Diuretics (furosemide)

  5. Manage blood pressure, reduce work of heart & myocardial O2 demand: Beta-blockers (metoprolol), ACE inhibitor (captopril), ARB (valsartan)
• Hypertrophic obstructive cardiomyopathy treatment

  1. Prevent cardiac arrest: Implantable cardiac defibrillator (ICD)

  2. Decrease ventricular contractility: Beta-blockers (metoprolol)

  3. Decrease arrhythmias: Ca2+ channel blocker (verapamil, diltiazem)
• Cardiac output


  Volume (L) of blood pumped by the left ventricle in 1 minute (CO = HR x SV)
• Stroke volume


  Amount of blood ejected by the left ventricle with each contraction
• Ejection fraction


  How much blood is pumped out of the heart each minute: 55-70% normal; less than 50% abnormal
• Systemic vascular resistance


  The resistance in the circulatory system that is used to create blood pressure: Low SVR = Low BP; High SVR = High BP
• Heart failure


  • Chronic health problem: Acute episodes
  • Progressive and debilitating
  • No cure, only compensation
  • Inability of the heart to pump adequate output to accommodate the body's metabolic demands and the venous return
• Types of heart failure

  • Systolic failure: Left ventricle cannot contract forcefully enough to eject enough blood needed for good cardiac output
  • Diastolic failure: Left ventricle cannot relax enough to fill properly for good cardiac output
• Causes of left-sided heart failure

  • Hypertension (number 1 cause)
  • Ischemic heart disease
  • Acute coronary syndrome
  • Coronary artery disease
  • Myocardial infarction
  • Valve disease
• Causes of right-sided heart failure

  • Right-ventricular MI
  • Pulmonary problems (pulmonary hypertension, COPD, fibrosis)
• Symptoms of left-sided heart failure

  • Pulmonary congestion (edema = crackles)
  • Pink, frothy sputum
  • Dyspnea, orthopnea
  • Chest pain, palpitations
  • Activity intolerance, fatigue, weakness
• Symptoms of right-sided heart failure

  • Weight gain
  • Peripheral edema
  • Ascites
  • Jugular venous distension
  • Right upper quadrant pain
  • Hepatomegaly
  • Splenomegaly
• 1. type natriuretic peptide (BNP)


  Marker for heart failure in the elderly or compensated mild chronic heart failure (Memory trick: B = Broken Ventricles)
• Nursing care priorities for heart failure

  1. Increase gas exchange

  2. Increase perfusion

  3. Prevent (manage) pulmonary edema
• Promoting oxygenation and gas exchange

  1. Assess cardiopulmonary

  2. Monitor vital signs & daily weight

  3. Ventilation assistance

  4. Position in high Fowler's

  5. Administer oxygen as ordered

  6. Administer medications as ordered
• Promoting perfusion


  1. Preload: Nutrition therapy, diuretics & venous vasodilators

  2. Afterload: ACE inhibitors, ARB, human BNP, venous vasodilators

  3. Contractility: Inotropes, beta-adrenergic agonists
• Cardiac glycoside


  • Increases contractility, reduces heart rate, slows conduction through atrioventricular node
  • Nursing considerations: Check apical pulse, hold if HR < 60, K+ < 3.5, Dig Level > 2.0, watch for Dig toxicity (vision changes, N/V, fatigue, dizziness)
• Other interventions for heart failure

  • Anticoagulants
  • Inhalers, breathing treatments
  • Cardiac rehab
  • Nutritional consult
  • Morphine
  • Surgery
• Surgical management of heart failure

  • VADs
  • Heart transplantation
  • Other surgical therapies (heart reduction, endoventricular circular patch cardioplasty, Acorn cardiac support device, Myosplint)
• Heart failure decompensation and complications

  • Rapid weight gain
  • Decreased activity intolerance
  • Signs of a cold
  • Excessive nocturia
  • Development of angina and dyspnea at rest
  • Acute pulmonary edema
  • Cardiogenic shock
  • Pericardial tamponade
  • Increased peripheral edema
• Hypothalamus


  Releases TRH-thyrotropin releasing hormone
• Pituitary gland


  Releases TSH whose function is to trigger the thyroid gland that more thyroid hormone is needed
• Thyroid gland


  Releases T4-thyroxine (94%), the inactive hormone, and 6% of the active hormone, T3, triiodothyronine
• Thyroid hormone release


  This is known as a negative feedback loop
• T4 is then converted to the active T3 in the liver and gut
• Hypothalamus-Pituitary-Thyroid Axis, Negative Feedback Loop

  • Anterior Pituitary
  • Hypothalamus
  • Portal vessels
  • Thyrotropin Releasing Hormone (TRH)
  • Thyroid Stimulating Hormone (TSH)
  • T3
  • T4
  • Posterior Pituitary
  • Thyroid
  • Liver
  • Gut
• Thyroid gland


  • Located in the inferior anterior neck
• Hyperthyroidism


  Excessive thyroid replacement hormones
• Types of hyperthyroidism


  • Toxic multinodular goiter
  • Graves' disease
  • Excessive thyroid replacement hormones
• Graves' disease


  • Most frequent cause of hyperthyroidism, usually has goiter, exophthalmos, pretibial myxedema
• Hyperthyroidism affects women 10 times more than men, usually diagnosed at age 20-40
• Symptoms of hyperthyroidism


  • Heat intolerance
  • Heart palpitations
  • Dyspnea
  • Fatigue, weakness
  • Insomnia
  • Amenorrhea, or decreased flow
  • Irritability
  • Changes in vision
  • Smooth skin, hair loss
  • Weight loss despite increased appetite
  • Exophthalmos
  • Goiter
  • Increased stools
  • Manic
  • Muscle wasting
• Diagnostic tests for hyperthyroidism

  • T3, T4, TSH
  • Thyroid scan
  • Ultrasound
  • ECG
• Nonsurgical management of hyperthyroidism

  • Monitoring vital signs
  • Reducing stimulation
  • Promoting comfort
  • Drug therapy (anti-thyroid drugs, iodine preparations, lithium, beta-adrenergic blocking drugs)
  • Teach safety precautions for radioactive iodine therapy