Cor pulmonale

Background

• Remodeling of right ventricle in response to pulmonary pathology
• Often caused by COPD, pulmonary hypertension, PE, ARDS

Clinical Features

Pathophysiology

• Pulmonary vasoconstriction (hypoxia, acidemia)
• Destruction of pulmonary vasculature by emphysema, ILD
• Increased blood viscosity (sickle cell disease, polycythemia)

Chronic

• RVH

Acute

• RV dilation

Signs and Symptoms

• Cough
• Dyspnea
• Tachypnea
• Hemoptysis
• Syncope
• Peripheral edema
• Cyanosis

Differential Diagnosis

• Cardiovascular
  • ACS
  • Acute Valve Dysfunction
  • Aortic Dissection
  • Dysrhthymia
  • Endocarditis
  • Hypertensive Emergency
  • Pericardial Tamponade
• Pulmonary
  • COPD
  • PE
  • PNA
• Other
  • Pure volume overload
    • Renal Failure
    • Post-Transfusion
  • Sepsis

Causes of Decompensation

• Medication noncompliance
• Dietary noncompliance
• Uncontrolled HTN
• MI
• Valvular Dysfunction
• Arrhythmias
• Infection
• Inappropriate medications (e.g., negative inotropes)
• Fluid overload
• Missed dialysis
• Thyrotoxicosis
• Anemia
• Alcohol Withdrawal

Diagnosis

Blood tests

• CBC (polycythemia)
• ABG (oxygenation, acid-base status)
• alpha-1-antitrypsin
• ANA
• Coagulation studies (protein C/S, factor V Leiden etc)

CXR

• Enlarged pulmonary arteries
• Cardiomegaly
• Decreased retrosternal air space

EKG

• RVH
• Right axis deviation
• Right bundle branch block
• R:S ratio > 1 in V1
• Large P wave in II, III, aVF
• Arrhythmia (PAC, SVT, MFAT, A-fib, A-flutter)

Echo

• Increased RV thickness
• RV dilation
• Tricuspid insufficiency
• High estimated PA pressures
• Septal bowing into LV

Management

• Treat underlying disease
• Fluids, vasoconstrictors to support BP in acute setting
• Oxygen therapy: decreases pulmonary vasoconstriction
• Diuretics: decrease RV filling volume
• Calcium channel blockers: vasodilate the pulmonary arteries
• Beta agonists (epoprostenol, iloprost): bronchodilate
• Phlebotomy for severe hypoxia leading to polycythemia
• Lung transplant or heart-lung transplant as last resort

References

• http://emedicine.medscape.com/article/154062-overview#a23. Updated Oct 6, 2014. Accessed Sept 9, 2015.