Abstract 17112: Continuous Preload Measurement to Modulate Treatment of Heart Failure
Introduction: In managing heart failure, increased physician intervention and medication-adjustment in response to changes in hemodynamic status has been proven to reduce morbidity. In practice, this can be accomplished through the optimization of pulmonary artery pressure (PAP) range using a dedicated, unpowered implant/reader combination. However, there is a large population of patients with already implanted and powered devices (ICDs & CRT-Ds), most of whom have appreciable risk. These patients would benefit from technology that enables their existing ICDs and leads to make hemodynamic measurements of preload.
Hypothesis: A repeatable measurement of preload (LV EDV) can be made using a single-coil defibrillator lead with high agreement to a volume standard such as 3D Trans-Thoracic Echo (TTE).
Methods: RECHARGE is a first-in-human trial performed in N=21 patients to determine the agreement between 3D TTE and RV lead determination of EDV. Volume was modulated by overdrive pacing at +10 and +50 bpm above baseline heart rate to reduce filling time, which reduces EDV. RV lead volume was calibrated to baseline 3D TTE on a patient-by-patient basis, to ensure that variation in lead scarring, placement, and brand would not affect the volume calculation.
Results: Concordance and Intraclass Correlation (CCC, ICC) between 3D TTE and RV lead EDV measurement was high (CCC=0.95, ICC=0.95). RV lead EDV had a mean within-subject Coefficient of Variation (wCV) of 2.4% (0% is perfect repeatability), while echo wCV was much higher at 9.9%. This implies that much of the agreement discrepancy in the study is due to high echo variability, and that RV lead volumes are more reliable than echo. Bland-Altman limits of agreement were LOA80% = (-17,% 17%).
Conclusions: Statistics show excellent agreement between preload measurements made using a single coil RV lead and 3D TTE, implying that EDV could be measured with high repeatability in an ambulatory setting, without a dedicated implant.
Author Disclosures: D.E. Haines: None. W. Wong: Ownership Interest; Significant; Admittance Technologies, Inc.. R.C. Canby: None. C. Jewell: None. D. Pederson: None. M. Houmsse: None. L. Sugeng: None. J.E. Porterfield: Employment; Significant; Admittance Technologies, Inc.. Ownership Interest; Modest; Admittance Technologies, Inc. A.T. Kotam: Employment; Significant; Admittance Technologies, Inc. J.A. Pearce: Ownership Interest; Modest; Admittance Technologies, Inc. J.W. Valvano: Ownership Interest; Significant; Admittance Technologies, Inc.. S. Sagar: None. M.D. Feldman: Ownership Interest; Significant; Admittance Technologies, Inc.. Consultant/Advisory Board; Modest; Admittance Technologies, Inc..
- © 2016 by American Heart Association, Inc.