Primary pulmonary hypertension

Dyspnea is the most common symptom of primary pulmonary hypertension, an often fatal disease that has no apparent cause. Decreased cardiac output, congestive heart failure, and increased systemic venous pressure occur as the disease progresses. Use of oxygen therapy and vasodilators improves the prognosis in some patients. Those with little hope for long-term survival may benefit from heart and lung transplantation.