title: Hemodynamic factors associated with acute decompensated heart failure: part 2--use in automated detection.
abstract: BACKGROUND
  The purpose of this study was to develop an automated surveillance system, using pressure-based hemodynamic factors that would detect which patients were making the transition from compensated to decompensated heart failure before they developed worsening symptoms and required acute medical care.
  
  
  RESULTS
  Intracardiac pressures in 274 patients with heart failure were measured using an implantable hemodynamic monitor (IHM) and were analyzed in a retrospective manner. An automated pressure change detection (PCD) algorithm was developed using the cumulative sum method. The performance characteristics of the PCD algorithm were defined in all patients who developed a heart failure-related event (HFRE); patients without HFRE served as controls. Optimal PCD threshold values were chosen using a receiver operator curve analysis. Each of the pressures measured with the IHM were evaluated using the PCD analysis. All had sensitivities ≥80% and false-positive rates <4.7/patient-year; however, estimated pulmonary artery diastolic pressure (ePAD) had the best performance. An ePAD based on the optimized PCD threshold of 6.0 yielded a sensitivity of 83% and a false-positive rate of 4.1/patient-year for detecting patients making the transition from compensated to decompensated heart failure. These performance characteristics were not significantly different for patients with an ejection fraction > vs. <50%, estimated glomerular filtration rate > vs. <60 mL/min/1.73 m(2), or age > vs. <60 years.
  
  
  CONCLUSIONS
  The automated PCD algorithm had high sensitivity and acceptable false-positive rates in detecting the development of decompensated heart failure before the patient developed worsening symptoms and required acute medical care. These data support the development of a prospective study to examine the utility of adding an automated PCD algorithm to IHM-based management strategies to prevent decompensated heart failure.
authors.affiliation: Oklahoma Foundation for Cardiovascular Research, Oklahoma Heart Hospital, Oklahoma City, OK, USA.
authors.forename: Philip B
authors.initials: PB
authors.lastname: Adamson
authors.forename: Michael R
authors.initials: MR
authors.lastname: Zile
authors.forename: Yong K
authors.initials: YK
authors.lastname: Cho
authors.forename: Tom D
authors.initials: TD
authors.lastname: Bennett
authors.forename: Robert C
authors.initials: RC
authors.lastname: Bourge
authors.forename: Mark F
authors.initials: MF
authors.lastname: Aaron
authors.forename: Juan M
authors.initials: JM
authors.lastname: Aranda
authors.forename: William T
authors.initials: WT
authors.lastname: Abraham
authors.forename: Fred J
authors.initials: FJ
authors.lastname: Kueffer
authors.forename: Robert T
authors.initials: RT
authors.lastname: Taepke
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D018660:Blood Pressure Monitoring, Ambulatory / Q000379:methods*; D005260:Female; D006333:Heart Failure / Q000175:diagnosis* / Q000503:physiopathology*; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D011446:Prospective Studies; D012189:Retrospective Studies