Pulmonary hypertension.

摘要

PH occurs when a disease elevates pulmonary arterial pressure above normal. Pulmonary artery pressure=left atrial pressure+(pulmonary flowXpulmonary vascular resistance). Any single factor or combination of factors that increases left atrial pressure, pulmonary flow, or resistance can cause PH.PH often is progressive, and if untreated, the right ventricle eventually becomes unable to support the circulation, resulting in significant morbidity and mortality. Pulmonary arterial pressure exceeding 25 mm Hg is abnormal and requires evaluation. Early treatment aimed at the underlying disease process may prevent progression. The prognosis is determined by the reversibility of the underlying disease process.