Pulmonary-Artery Aneurysm

A woman with pulmonary hypertension presented with shortness of breath and changes in mental status. A 66-year-old woman with a 20-year history of severe primary pulmonary hypertension presented with progressive shortness of breath, weakness, and changes in mental status. There was a palpable systolic impulse in the second left anterior intercostal space. Arterial blood gas values during the administration of oxygen were as follows: pH, 7.14; partial pressure of carbon dioxide, 175 mm Hg; partial pressure of oxygen, 88 mm Hg; and bicarbonate concentration, 60 mmol per liter. Chest radiography performed after intubation (Panel A) revealed 80 percent opacification of the left lung field and an enlarged right hilum. Computed tomographic scanning showed that the . . .