Pulmonary Hypertension Associated with Heart Failure with Preserved Ejection Fraction: Acute Hemodynamic Effects of Inhaled Iloprost

Iloprost, an inhaled synthetic prostacyclin analogue, improves hemodynamic and clinical status with minimal systemic adversity in patients with pulmonary arterial hypertension. Our single‐site, prospective case series aimed to determine the effects of iloprost in subjects with group 2 pulmonary hypertension and heart failure with preserved ejection fraction. Patients referred to Boston Medical Center for initial evaluation of suspected pulmonary hypertension received a test dose of 2.5 μg inhaled iloprost, followed by two subsequent doses of 5 μg. Hemodynamic measurements were recorded for each inhalation after 15, 30, 60, and 90 minutes. Results were analyzed via paired t test and signed‐rank test. Eight subjects fulfilled criteria and elected to enter the study. There was a reduction of pulmonary arterial pressure (by an average of 7.0 mmHg [ P = 0.005] and 4.7 mmHg [ P = 0.021] with the first and second 5‐μg inhalations, respectively) and pulmonary vascular resistance (by an average of 161.9 dyn· s/cm 5 [ P = 0.019] and 95.0 dyn · s/cm 5 [ P = 0.014] with the first and second 5‐μg inhalations, respectively). There were trends for increased cardiac output and decreased oxygen saturation. There were no changes in other vital or hemodynamic parameters, including pulmonary capillary wedge pressure. All patients completed each cycle of iloprost administration without preestablished termination criteria. In patients with pulmonary hypertension and heart failure with preserved ejection fraction, inhaled iloprost resulted in acute reduction of pulmonary arterial pressure and pulmonary vascular resistance. Further evaluation of iloprost in this subset of patients is warranted.