Pulmonary and Pleural Complications of Cardiac Disease

Disorders of the heart frequently cause pulmonary dysfunction because of the close structural and functional association of the heart and lungs. The pulmonary vasculature is very commonly affected by cardiac pathology. The pulmonary vasculature is normally a low-pressure, low-resistance circuit with high compliance and tremendous vascular reserve. Although resting vascular tone is low, there are many identified mediators of pulmonary arterial tone that may help mediate pulmonary blood flow. Alveolar hypoxia is clearly a stimulus for increasing pulmonary vascular resistance although factors that mediate the response to hypoxia are not fully understood.