We do not believe that the issue Dr Fisch raises is important for several reasons. First, although the pain allegedly owing to pulmonary hypertension has been described as an anginal-type pain, review of the literature shows that what was described was often nonexertional pain. Second, there is no reason to believe that many persons with a normal pulmonary artery pressure at rest would experience substantial pulmonary hypertension with exercise as a cause for chest pain with exertion. Third, our subjects with severe hypertension at rest had not experienced chest pain of any severity either at rest or with exercise. Finally, many of the patients underwent angiography during cardiac catheterization. Angiography may cause hemodynamic changes akin to those of exercise. Pressure measurements after angiography are not substantially different from rest pressures.