Only 12 of the 19 patients had the special catheter tests; only 8 patients completed the 6-minute walk test at baseline, and 9 completed that test after 3 months of treatment. The tests of heart function showed improvement after 3 months. The distance patients could walk in 6 minutes improved an average of 148 meters, an increase of nearly 100% compared to how far they could walk before treatment. Four patients died before completing 3 months of treatment. Of the remaining 15 patients, 8 stopped taking iloprost after about 1 year because they got lung transplants, 1 patient switched to intravenous prostacyclin, and another 3 died after the end of the 3-month study period. Seven patients continued to receive iloprost at the time that the researchers completed this report.