title: Comparison of a radiofrequency-based wireless pressure sensor to swan-ganz catheter and echocardiography for ambulatory assessment of pulmonary artery pressure in heart failure.
abstract: OBJECTIVE
  The goal of this work was to evaluate the accuracy of a new heart failure (HF) sensor (HFS) (Heart Failure Sensor, CardioMEMS Inc., Atlanta, Georgia) pulmonary artery pressure (PAP) monitoring compared with Swan-Ganz (SG) (Hospira, Inc., Lake Forest, Illinois) catheterization and echocardiography (ECHO) in ambulatory HF patients.
  
  
  BACKGROUND
  There is an increasing interest in the development of ambulatory monitoring devices aiming to adjust therapy and prevent hospitalizations in HF patients.
  
  
  METHODS
  Twelve patients with HF and New York Heart Association functional class II to IV were included in this study. The HFS was deployed into the pulmonary artery under angiography, allowing wireless PAP measurement. Two independent blind operators performed 3 HFS measurements at each visit, with simultaneous ECHO at 2, 14, 30, 60, and 90 days. Swan-Ganz catheterization was performed at 0 and 60 days. Linear regression was used as a measure of agreement. Variability between methods and interobserver variability were evaluated by Bland-Altman analysis.
  
  
  RESULTS
  Mean age was 63 +/- 14.6 years. Systolic PAP was 64 +/- 22 mm Hg and 58 +/- 22 mm Hg for HFS and SG, respectively (p < 0.01). Both methods showed a significant correlation (r2 = 0.96 baseline, r2 = 0.90 follow-up, p < 0.01), with a mean difference of 6.2 +/- 4.5 mm Hg. Diastolic PAP was 23 +/- 14 mm Hg and 28 +/- 16 mm Hg for HFS and SG, respectively (r2 = 0.88 baseline, r2 = 0.48 follow-up, p < 0.01), with a mean difference of -1.6 +/- 6.8 mm Hg. Systolic PAP was 60 +/- 20 mm Hg and 62 +/- 12 mm Hg for HFS and ECHO, respectively (r2 = 0.75, p < 0.01), with a mean difference of -2.6 +/- 11 mm Hg. There was no significant interobserver difference.
  
  
  CONCLUSIONS
  The HFS provides an accurate method for PAP assessment in the intermediate follow-up of HF patients.
authors.affiliation: Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Hugo E
authors.initials: HE
authors.lastname: Verdejo
authors.forename: Pablo F
authors.initials: PF
authors.lastname: Castro
authors.forename: Roberto
authors.initials: R
authors.lastname: Concepción
authors.forename: Marcela A
authors.initials: MA
authors.lastname: Ferrada
authors.forename: Mario A
authors.initials: MA
authors.lastname: Alfaro
authors.forename: Milton E
authors.initials: ME
authors.lastname: Alcaíno
authors.forename: Carlos C
authors.initials: CC
authors.lastname: Deck
authors.forename: Robert C
authors.initials: RC
authors.lastname: Bourge
mesh_terms: D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D018660:Blood Pressure Monitoring, Ambulatory / Q000295:instrumentation*; D002407:Catheterization, Swan-Ganz / Q000295:instrumentation*; D015150:Echocardiography, Doppler; D025802:Electric Capacitance; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000503:physiopathology; D015588:Observer Variation; D019736:Prostheses and Implants; D011669:Pulmonary Wedge Pressure / Q000502:physiology*; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D013223:Statistics as Topic; D014160:Transducers, Pressure; D014262:Tricuspid Valve Insufficiency / Q000175:diagnosis / Q000503:physiopathology