Effects of Inhaled Iloprost on Exercise Capacity, Quality of Life, and Cardiac Function in Patients With Pulmonary Arterial Hypertension Secondary to Congenital Heart Disease (the Eisenmenger Syndrome) (from the EIGER Study)

There are limited data on the effect of iloprost therapy in patients with Eisenmenger syndrome (ES). The aim of our study was to evaluate the effect of inhaled iloprost therapy on exercise capacity, quality of life (QoL), cardiac function, and hemodynamics in patients with ES. Eighteen consecutive patients with ES and exertional dyspnea according to the World Health Organization functional class III or IV were prospectively recruited. Exercise capacity was assessed by a 6-minute walk test, and QoL was measured on a 12-Item Short-Form Health Survey. Echocardiographic measurements included peak systolic and mean pulmonary arterial pressures, pulmonary vascular resistance, and myocardial performance index of the right ventricle (RV). All patients underwent comprehensive evaluation at baseline and after 24 weeks of treatment. Of the 18 patients with ES, 13 were included for analysis. After 24 weeks of iloprost therapy, 6-minute walk test distance significantly increased (289.1 ± 76.9 to 369.5 ± 93.4 m, p = 0.032) in addition to concomitant improvements in the 12-Item Short-Form Health Survey physical and mental component summaries (20.6 ± 19.3 to 52.6 ± 28.0, p <0.05; 33.9 ± 19.7 to 54.9 ± 21.3, p <0.05, respectively). RV myocardial performance index improved significantly after treatment (0.80 ± 0.31 to 0.59 ± 0.12, p = 0.042). Pulmonary arterial pressure and pulmonary vascular resistance did not improve with iloprost therapy. This study showed that 24 weeks of inhaled iloprost therapy in patients with ES led to significant improvements in exercise capacity, QoL, and RV function. These results likely explain the symptomatic relief reported by patients with ES receiving iloprost therapy.