Cardiovascular Medicine Book

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Pulmonary Hypertension

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  1. Definitions
    1. Pulmonary Hypertension
      1. Pulmonary artery systolic prEssure >30 mmHg
      2. Pulmonary artery mean prEssure >20 mmHg
    2. Primary Pulmonary Hypertension
      1. Idiopathic Pulmonary Hypertension
    3. Secondary Pulmonary Hypertension
      1. Secondary to one of Pulmonary Hypertension Causes
    4. Cor Pulmonale
      1. Right ventricular failure
      2. Second to respiratory cause of Pulmonary Hypertension
  2. Epidemiology: Primary Pulmonary Hypertension
    1. Incidence: 1-2 cases per 1 million
    2. Female predominance after Puberty in ratio of 1.7 to 1
    3. Most prevalent in ages 20 to 40 years old
  3. Types (replaces old system of primary versus secondary Pulmonary Hypertension)
    1. Pulmonary artery Hypertension
      1. Idiopathic or familial
      2. Includes persistent Pulmonary Hypertension of the newborn
      3. Collagen vascular disease
      4. HIV Infection
    2. Pulmonary Hypertension associated with left heart disease
      1. Left-sided valvular heart disease
      2. Left-sided atrial or ventricular heart disease
    3. Pulmonary Hypertension associated with lung disease, Hypoxemia or both
      1. Chronic Obstructive Lung Disease
      2. Interstitial Lung Disease
      3. Sleep Apnea
      4. Chronic high altitude exposure
    4. Pulmonary Hypertension associated with chronic thromboembolic disease
      1. Thromboembolism of proximal or distal pulmonary arteries
      2. Thromboembolism not due to thrombi (e.g. tumor, parasites)
    5. Miscellaneous Pulmonary Hypertension
      1. Sarcoidosis
      2. Pulmonary vessel compression
  4. Causes
    1. See Pulmonary Hypertension Causes
  5. Symptoms
    1. Common
      1. Progressive Dyspnea on exertion
      2. Fatigue
      3. Syncope
    2. Less Common
      1. Hoarseness (Oertner Syndrome)
        1. Pulmonary artery compress left recurrent laryngeal
      2. Angina-type exertional Chest Pain
    3. Rare
      1. Cough
      2. Hemoptysis
      3. Raynaud's Phenomenon (2%)
  6. Signs
    1. Jugular vein distention
    2. Prominent right ventricular impulse
    3. Accentuated second pulmonic valve component (P2)
      1. Louder than the aortic second sound (A2)
      2. A2 remains louder as stethoscope moved to apex
    4. Right Ventricular Fourth Heart Sound (S4 Heart Sound)
    5. Right-sided Third Heart Sound (S3 Heart Sound)
      1. Indicates advanced disease
      2. Associated with poor prognosis
    6. Tricuspid insufficiency murmur
      1. More prominent as right ventricle dilates
    7. Hepatomegaly
    8. Peripheral edema
  7. Diagnosis
    1. See Pulmonary Hypertension Diagnosis
    2. Mean Pulmonary Artery PrEssure (normally <15 mmHg)
      1. Rest: 25 mmHg or higher
      2. Exercise: 30 mmHg or higher
  8. Management
    1. Treat underlying cause
      1. Treat Mitral Stenosis
      2. Afterload reduction for Left Ventricular Dysfunction
      3. Avoid predisposing medications (weight loss drugs)
      4. Prevent and treat respiratory infections
    2. Evaluate WHO functional class status
      1. Six minute walk test
    3. Determine if patient responds to vasodilation
      1. Perform right heart catheterization (mandatory prior to using CCB)
      2. Administer vasodilator (e.g. Adenosine, epoprostenol)
      3. Responder criteria
        1. Pulmonary Artery PrEssure decreases >10 mmHg and <40 mmHg
        2. Cardiac output does not change or increases
      4. Use responder status to direct therapy
        1. Responder: Calcium Channel Blocker
        2. Non-responder: Use other vasodilators listed below
    4. General measures
      1. Regular symptom-limited Exercise
      2. Avoid pregnancy (50% mortality)
      3. Oxygen supplementation to keep Oxygen Saturation >90%
    5. Medications
      1. Calcium Channel Blockers
        1. Effective longterm in only 20%
        2. Agents (use high dose): Diltiazem, Nifedipine, Amlodipine
        3. Requires vasodilation test as above (use if responder)
          1. If non-responder, then do not use Calcium Channel Blocker
          2. Use other vasodilators listed below
      2. Vasodilators (reduce vascular resistance)
        1. Low flow Supplemental Oxygen (as above)
        2. Endothelin receptor antagonists (Bosentan, Ambrisentan)
          1. FDA pregnancy category X (and reduce OCP efficacy)
          2. Liver Function Testing monthly
        3. PDE-5 Inhibitors (Sildenafil)
          1. Do not use with nitrates
        4. Prostenoids (Prostacyclin): Epoprostenol, Iloprost, Trepostinil
          1. Highly effective
        5. Nitric oxide (experimental)
      3. Anticoagulation
        1. Coumadin to keep INR between 1.7 to 2.2
      4. Cardiac Output maximization
        1. Parenteral inotropic medications
        2. Digoxin
      5. Decrease preload
        1. Follow low-salt diet
        2. Diuretics
    6. Surgery: Lung Transplantation
  9. Complications: Right Ventricular Failure
    1. Secondary to persistent Pulmonary Hypertension
    2. Cor Pulmonale: Subtype of right ventricular failure
      1. Second to respiratory cause of Pulmonary Hypertension
  10. Prognosis: Primary Pulmonary Hypertension
    1. Median survival from diagnosis
      1. Prior medications: 2.8 years
      2. New medications: may exceed 10 years
  11. References
    1. Gaine (2000) JAMA 284:3160
    2. Nauser (2001) Am Fam Physician 63(9):1789
    3. Rubin (1997) N Engl J Med 336:111
    4. Rubin (1993) Chest 104:236

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