title: Sensitivity and positive predictive value of implantable intrathoracic impedance monitoring as a predictor of heart failure hospitalizations: the SENSE-HF trial.
abstract: OBJECTIVE
  Early recognition of impending decompensation and timely intervention may prevent heart failure (HF) hospitalization. We investigated the performance of OptiVol® intrathoracic fluid monitoring for the prediction of HF events in chronic HF patients newly implanted with a device (implantable cardioverter-defibrillator with or without cardiac resynchronization therapy).
  
  
  RESULTS
  SENSE-HF was a prospective, multi-centre study that enrolled 501 patients. Phase I (double blinded, 6 months) determined the sensitivity and positive predictive value (PPV) of the OptiVol data in predicting HF hospitalizations. Of 58 adjudicated HF hospitalizations that occurred during the first 6 months in Phase I, 12 were predicted by OptiVol (sensitivity = 20.7%). Sensitivity appeared to be dynamic in nature and at the end of Phase I, had increased to 42.1%. With 253 OptiVol detections, PPV for Phase I was 4.7%. Phase II/III (unblinded, 18 months) determined the PPV of the first OptiVol Patient Alert for detection of worsening HF status with signs and/or symptoms of pulmonary congestion. A total of 233 patients noted such an OptiVol alert and for 210, HF status was evaluated within 30 days. Heart failure status had worsened for 80 patients (PPV = 38.1%).
  
  
  CONCLUSIONS
  An intrathoracic impedance-derived fluid index had low sensitivity and PPV in the early period after implantation of a device in chronic HF patients. Sensitivity improved within the first 6 months after implant. Further studies are needed to assess the place of this monitoring technology in the clinical management of patients with HF.
authors.affiliation: Department of Cardiology, Antwerp University Hospital, Wilrijkstraat 10, Edegem, Belgium. viviane.conraads@uza.be
authors.forename: Viviane M
authors.initials: VM
authors.lastname: Conraads
authors.forename: Luigi
authors.initials: L
authors.lastname: Tavazzi
authors.forename: Massimo
authors.initials: M
authors.lastname: Santini
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Oliva
authors.forename: Bart
authors.initials: B
authors.lastname: Gerritse
authors.forename: Cheuk-Man
authors.initials: CM
authors.lastname: Yu
authors.forename: Martin R
authors.initials: MR
authors.lastname: Cowie
mesh_terms: D000368:Aged; D002307:Cardiography, Impedance / Q000295:instrumentation*; D017147:Defibrillators, Implantable; D004311:Double-Blind Method; D042241:Early Diagnosis; D004567:Electrodes, Implanted; D005260:Female; D006333:Heart Failure / Q000517:prevention & control*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000295:instrumentation; D012680:Sensitivity and Specificity