To the Editor: The articles by Rubin and Peter and by Klinke and Gilbert in the January 10 issue, describing the beneficial effects of systemic vasodilators in the therapy of pulmonary hypertension, generated a considerable response. In the May 29 issue, Olukotun suggested that such agents be evaluated in secondary pulmonary hypertension, and Rich emphasized the hazards of such therapy.We are writing to report on the hemodynamic responses to vasodilator therapy in a patient with severe pulmonary hypertension and cor pulmonale secondary to chronic multiple pulmonary emboli. The patient is a 39-year-old man who sustained blunt trauma to the . . .