title: Wireless pulmonary artery haemodynamic monitoring in chronic heart failure: a randomised controlled trial.
abstract: BACKGROUND
  Results of previous studies support the hypothesis that implantable haemodynamic monitoring systems might reduce rates of hospitalisation in patients with heart failure. We undertook a single-blind trial to assess this approach.
  
  
  METHODS
  Patients with New York Heart Association (NYHA) class III heart failure, irrespective of the left ventricular ejection fraction, and a previous hospital admission for heart failure were enrolled in 64 centres in the USA. They were randomly assigned by use of a centralised electronic system to management with a wireless implantable haemodynamic monitoring (W-IHM) system (treatment group) or to a control group for at least 6 months. Only patients were masked to their assignment group. In the treatment group, clinicians used daily measurement of pulmonary artery pressures in addition to standard of care versus standard of care alone in the control group. The primary efficacy endpoint was the rate of heart-failure-related hospitalisations at 6 months. The safety endpoints assessed at 6 months were freedom from device-related or system-related complications (DSRC) and freedom from pressure-sensor failures. All analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00531661.
  
  
  RESULTS
  In 6 months, 83 heart-failure-related hospitalisations were reported in the treatment group (n=270) compared with 120 in the control group (n=280; rate 0·31 vs 0·44, hazard ratio [HR] 0·70, 95% CI 0·60-0·84, p<0·0001). During the entire follow-up (mean 15 months [SD 7]), the treatment group had a 39% reduction in heart-failure-related hospitalisation compared with the control group (153 vs 253, HR 0·64, 95% CI 0·55-0·75; p<0·0001). Eight patients had DSRC and overall freedom from DSRC was 98·6% (97·3-99·4) compared with a prespecified performance criterion of 80% (p<0·0001); and overall freedom from pressure-sensor failures was 100% (99·3-100·0).
  
  
  CONCLUSIONS
  Our results are consistent with, and extend, previous findings by definitively showing a significant and large reduction in hospitalisation for patients with NYHA class III heart failure who were managed with a wireless implantable haemodynamic monitoring system. The addition of information about pulmonary artery pressure to clinical signs and symptoms allows for improved heart failure management.
  
  
  BACKGROUND
  CardioMEMS.
authors.affiliation: Ohio State University Heart and Vascular Center, Columbus, OH, USA.
authors.forename: William T
authors.initials: WT
authors.lastname: Abraham
authors.forename: Philip B
authors.initials: PB
authors.lastname: Adamson
authors.forename: Robert C
authors.initials: RC
authors.lastname: Bourge
authors.forename: Mark F
authors.initials: MF
authors.lastname: Aaron
authors.forename: Maria Rosa
authors.initials: MR
authors.lastname: Costanzo
authors.forename: Lynne W
authors.initials: LW
authors.lastname: Stevenson
authors.forename: Warren
authors.initials: W
authors.lastname: Strickland
authors.forename: Suresh
authors.initials: S
authors.lastname: Neelagaru
authors.forename: Nirav
authors.initials: N
authors.lastname: Raval
authors.forename: Steven
authors.initials: S
authors.lastname: Krueger
authors.forename: Stanislav
authors.initials: S
authors.lastname: Weiner
authors.forename: David
authors.initials: D
authors.lastname: Shavelle
authors.forename: Bradley
authors.initials: B
authors.lastname: Jeffries
authors.forename: Jay S
authors.initials: JS
authors.lastname: Yadav
mesh_terms: D000368:Aged; D018660:Blood Pressure Monitoring, Ambulatory / Q000295:instrumentation*; D006328:Cardiac Catheterization / Q000295:instrumentation; D004567:Electrodes, Implanted; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005500:Follow-Up Studies; D006333:Heart Failure / Q000175:diagnosis* / Q000503:physiopathology*; D006439:Hemodynamics / Q000502:physiology*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D056656:Lab-On-A-Chip Devices; D008875:Middle Aged; D011651:Pulmonary Artery; D011669:Pulmonary Wedge Pressure / Q000502:physiology*; D058998:Remote Sensing Technology / Q000295:instrumentation*; D016037:Single-Blind Method