cor pulmonale

Introduction

Enlargement of the right ventricle secondary to disease of the lung, thorax or pulmonary circulation. It may be accompanied by right ventricular failure with elevation of right ventricular end-diastolic pressure.

Etiology

(pulmonary hypertension)

• chronic bronchitis (50%), uncommon with emphysema
• pulmonary emboli
• acute respiratory distress syndrome (ARDS)
• pulmonary vasculitis
• restrictive lung disease
  • intrinsic disease
    • interstitial fibrosis
    • lung resection
  • extrinsic disease
    • obesity
    • myxedema
    • kyphoscoliosis
    • high altitude
    • diminished contraction of muscles of respiration

Clinical manifestations

• dyspnea
  • on exertion or at rest
  • not relieved by sitting up
• non-productive cough
• jugular venous distension
• hepatomegaly
• hepatojugular reflux
• ankle edema
• S3 gallop increasing with inspiration may be present
• fixed splitting of 2nd heart sound may be present
  • loud pulmonic component of 2nd heart sound (P2)
• physical findings of right ventricular failure may resolve when pulmonary artery pressure is reduced by relief of hypoxemia

Diagnostic procedures

• electrocardiogram:
  • evidence of right ventricular hypertrophy
  • RBBB in 15%
  • multifocal atrial tachycardia may be associated with decompensated COPD
• lung biopsy to demonstrate vasculitis

Radiology

• chest X-ray
  • enlarged pulmonary trunk & hilar vessels
  • widening of right pulmonary artery shadow
  • cardiomegaly
• echocardiogram
  • enlargement of right ventricular cavity
  • elevation of right ventricular systolic pressure
  • tricuspid or pulmonic regurgitation may be noted
• magnetic resonance imaging (MRI)
  • right ventricular mass
  • wall thickness
  • cavity volume
  • ejection fraction
• radionuclide ventriculography
• myocardial perfusion scintigraphy (Th-201 or sestamibi)
• cardiac catheterization
  • precise measurement of pulmonary vascular pressure
  • measurement of pulmonary vascular resistance
    • response to oxygen
    • response to vasodilators
  • pulmonary angiography to assess pulmonary vascular obstruction

Management

• optimal managemnt of underlying lung disorder
• judicious administration of oxygen
  • improves pulmonary vasoconstriction secondary to alveolar hypoxia & hypercarbia
  • reduces pulmonary artery pressure & pulmonary vascular resistance
  • diminished tachypnea & signs of right-sided heart failure
• bronchodilators may reduce airflow obstruction
• diuretic help relieve edema
  • loop diuretics may induce metabolic alkalosis & blunt respiratory drive
• digoxin if right ventricular failure is present
• phlebotomy if hematocrit > 55-60%

More general terms

• cardiopulmonary disease
• right ventricular failure; right heart failure

Additional terms

• pulmonary hypertension; pulmonary arterial hypertension