Cor pulmonale – acute and chronic

Cor pulmonale – acute and chronic

In simple terms, cor pulmonale is heart disease secondary to lung disease which causes pulmonary hypertension. It is associated with right ventricular hypertrophy and/or dilatation, which eventually leads to right heart failure. Chronic obstructive pulmonary disease  is the most common cause of cor pulmonale, mainly because of its frequency. But more severe pulmonary hypertension may be noted in interstitial lung disease with idiopathic pulmonary fibrosis. Acute cor pulmonale usually occurs in the setting of acute pulmonary embolism.

Acute exacerbation of COPD may be also associated with severe alveolar hypoxia leading to sudden rise in pulmonary arterial pressures and right heart failure. As hypoxia is the most important cause of pulmonary hypertension in this setting, the natural treatment is with oxygen, which is a potent pulmonary vasodilator. Home oxygen therapy with either a conventional oxygen cylinder or an oxygen concentrator which derives oxygen from room air has been in use for reducing pulmonary arterial hypertension.

Other alternatives for controlling pulmonary hypertension are prostacyclin, endothelin receptor antagonists, phosphodiesterase 5 inhibitors and nitric oxide. We need good quality randomized controlled trials to establish the long term utility and safety of these drugs in the setting of chronic cor pulmonale. Nitric oxide is given as inhalation in the acute care setting, especially in newborns.

Acute cor pulmonale due to acute pulmonary embolism responds to thrombolytic therapy as well as anticoagulation. Rheolytic thrombolysis is another option for acute pulmonary embolism. Surgical pulmonary thromboendarterectomy is useful in certain cases, even for chronic recurrent pulmonary embolism with severe pulmonary hypertension and right heart failure. Long term anticoagulation and inferior vena caval filters are useful in chronic recurrent pulmonary embolism causing cor pulmonale. Systemic therapy is needed in connective tissue disorders causing pulmonary hypertension.