Dr. Desai has nicely described the rational for considering pulmonary artery pressure (PAP) as a target for heart failure (HF) therapy.  To test the hypothesis that lowering PAP can reduce the risk of HF hospitalization for decompensation episodes, 550 patients were randomized into the prospective, multicenter, controlled, single-blind CHAMPION (CardioMEMS Heart Sensor Allows Monitoring of Pressure to Improve Outcomes in NYHA Class III Heart Failure Patients) trial,^[1] with all of the subjects followed until the last patient had reached 6 months of follow-up.  The primary efficacy endpoint was the rate of HF-related hospitalizations at 6 months, to test the hypothesis that PAP-guided HF management could lower the rate of HF hospitalization.

As shown in Figure 2, all 550 patients were implanted with the CardioMEMS PAP sensor system (see next Figure); 270 were randomized to a treatment arm and 280 to a control arm; the two arms differed in that those randomized to the treatment arm were managed according to the PAP levels recorded by their implanted PAP monitoring device, whereas the physicians were blinded to PAP levels for the subjects in the control arm and the patients were managed strictly on the basis of standard of care.  The primary endpoint was HF hospitalization at 6 months, but patients were followed for an average follow-up exceeding 15 months in order to evaluate the durability of effect.