Intraoperative Evaluation of the HeartMate II Flow Estimator

Mark S. Slaughter, Carlo R. Bartoli, Mike A. Sobieski, George M. Pantalos, Guruprasad A. Giridharan, Robert Dowling, Sumanth D. Prabhu, David J. Farrar, Steven C. Koenig

Research output: Contribution to journalArticle

39 Citations (Scopus)

Abstract

Background: Direct measurement of blood flow output has been incorporated into ventricular assist devices (VADs), but long-term reliability of the additional device components has raised concerns regarding sensor drift and failure. As an alternative approach, the HeartMate II axial VAD (Thoratec Corp, Pleasanton, CA) estimates device flow output from power consumption and rotational speed of the device motor. This study evaluated the accuracy of HeartMate II flow estimation at the time of implantation. Methods: In 20 patients, intraoperative blood flow measurement of the HeartMate II flow estimator was compared with flow values obtained with an ultrasonic flow probe placed around the device outflow graft. Estimated and measured VAD flow data were simultaneously recorded and digitally stored while the device motor speed varied from 7,800 to 11,000 rpm and while achieving device flow outputs of 2 to 7 liters/min. Estimated and measured flows were compared using linear regression analyses and root mean square error. Results: HeartMate II flow estimation (FE) demonstrated a linear correlation with ultrasonic flow probe (FP) measurements: FE = 0.74 FP + 0.99 (R2 = 0.56, p = 0.0001). A root mean square error of 0.8 liters/min was observed between flow estimation and direct flow measurement and suggests a 15% to 20% difference at flows of 4 of 6 liters/min. Conclusions: These results suggest that HeartMate II flow estimation may be used to provide directional information for trend purposes rather than absolute values of device blood flow output. Patient management should include but not be limited to this information.

Original languageEnglish (US)
Pages (from-to)39-43
Number of pages5
JournalJournal of Heart and Lung Transplantation
Volume28
Issue number1
DOIs
StatePublished - Jan 1 2009

Fingerprint

Equipment and Supplies
Heart-Assist Devices
Ultrasonics
Linear Models
Regression Analysis
Transplants

All Science Journal Classification (ASJC) codes

  • Surgery
  • Pulmonary and Respiratory Medicine
  • Cardiology and Cardiovascular Medicine
  • Transplantation

Cite this

Slaughter, M. S., Bartoli, C. R., Sobieski, M. A., Pantalos, G. M., Giridharan, G. A., Dowling, R., ... Koenig, S. C. (2009). Intraoperative Evaluation of the HeartMate II Flow Estimator. Journal of Heart and Lung Transplantation, 28(1), 39-43. https://doi.org/10.1016/j.healun.2008.10.007
Slaughter, Mark S. ; Bartoli, Carlo R. ; Sobieski, Mike A. ; Pantalos, George M. ; Giridharan, Guruprasad A. ; Dowling, Robert ; Prabhu, Sumanth D. ; Farrar, David J. ; Koenig, Steven C. / Intraoperative Evaluation of the HeartMate II Flow Estimator. In: Journal of Heart and Lung Transplantation. 2009 ; Vol. 28, No. 1. pp. 39-43.
@article{1654f8050de34ca98689f45f2be0c013,
title = "Intraoperative Evaluation of the HeartMate II Flow Estimator",
abstract = "Background: Direct measurement of blood flow output has been incorporated into ventricular assist devices (VADs), but long-term reliability of the additional device components has raised concerns regarding sensor drift and failure. As an alternative approach, the HeartMate II axial VAD (Thoratec Corp, Pleasanton, CA) estimates device flow output from power consumption and rotational speed of the device motor. This study evaluated the accuracy of HeartMate II flow estimation at the time of implantation. Methods: In 20 patients, intraoperative blood flow measurement of the HeartMate II flow estimator was compared with flow values obtained with an ultrasonic flow probe placed around the device outflow graft. Estimated and measured VAD flow data were simultaneously recorded and digitally stored while the device motor speed varied from 7,800 to 11,000 rpm and while achieving device flow outputs of 2 to 7 liters/min. Estimated and measured flows were compared using linear regression analyses and root mean square error. Results: HeartMate II flow estimation (FE) demonstrated a linear correlation with ultrasonic flow probe (FP) measurements: FE = 0.74 FP + 0.99 (R2 = 0.56, p = 0.0001). A root mean square error of 0.8 liters/min was observed between flow estimation and direct flow measurement and suggests a 15{\%} to 20{\%} difference at flows of 4 of 6 liters/min. Conclusions: These results suggest that HeartMate II flow estimation may be used to provide directional information for trend purposes rather than absolute values of device blood flow output. Patient management should include but not be limited to this information.",
author = "Slaughter, {Mark S.} and Bartoli, {Carlo R.} and Sobieski, {Mike A.} and Pantalos, {George M.} and Giridharan, {Guruprasad A.} and Robert Dowling and Prabhu, {Sumanth D.} and Farrar, {David J.} and Koenig, {Steven C.}",
year = "2009",
month = "1",
day = "1",
doi = "10.1016/j.healun.2008.10.007",
language = "English (US)",
volume = "28",
pages = "39--43",
journal = "Journal of Heart and Lung Transplantation",
issn = "1053-2498",
publisher = "Elsevier USA",
number = "1",

}

Slaughter, MS, Bartoli, CR, Sobieski, MA, Pantalos, GM, Giridharan, GA, Dowling, R, Prabhu, SD, Farrar, DJ & Koenig, SC 2009, 'Intraoperative Evaluation of the HeartMate II Flow Estimator', Journal of Heart and Lung Transplantation, vol. 28, no. 1, pp. 39-43. https://doi.org/10.1016/j.healun.2008.10.007

Intraoperative Evaluation of the HeartMate II Flow Estimator. / Slaughter, Mark S.; Bartoli, Carlo R.; Sobieski, Mike A.; Pantalos, George M.; Giridharan, Guruprasad A.; Dowling, Robert; Prabhu, Sumanth D.; Farrar, David J.; Koenig, Steven C.

In: Journal of Heart and Lung Transplantation, Vol. 28, No. 1, 01.01.2009, p. 39-43.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Intraoperative Evaluation of the HeartMate II Flow Estimator

AU - Slaughter, Mark S.

AU - Bartoli, Carlo R.

AU - Sobieski, Mike A.

AU - Pantalos, George M.

AU - Giridharan, Guruprasad A.

AU - Dowling, Robert

AU - Prabhu, Sumanth D.

AU - Farrar, David J.

AU - Koenig, Steven C.

PY - 2009/1/1

Y1 - 2009/1/1

N2 - Background: Direct measurement of blood flow output has been incorporated into ventricular assist devices (VADs), but long-term reliability of the additional device components has raised concerns regarding sensor drift and failure. As an alternative approach, the HeartMate II axial VAD (Thoratec Corp, Pleasanton, CA) estimates device flow output from power consumption and rotational speed of the device motor. This study evaluated the accuracy of HeartMate II flow estimation at the time of implantation. Methods: In 20 patients, intraoperative blood flow measurement of the HeartMate II flow estimator was compared with flow values obtained with an ultrasonic flow probe placed around the device outflow graft. Estimated and measured VAD flow data were simultaneously recorded and digitally stored while the device motor speed varied from 7,800 to 11,000 rpm and while achieving device flow outputs of 2 to 7 liters/min. Estimated and measured flows were compared using linear regression analyses and root mean square error. Results: HeartMate II flow estimation (FE) demonstrated a linear correlation with ultrasonic flow probe (FP) measurements: FE = 0.74 FP + 0.99 (R2 = 0.56, p = 0.0001). A root mean square error of 0.8 liters/min was observed between flow estimation and direct flow measurement and suggests a 15% to 20% difference at flows of 4 of 6 liters/min. Conclusions: These results suggest that HeartMate II flow estimation may be used to provide directional information for trend purposes rather than absolute values of device blood flow output. Patient management should include but not be limited to this information.

AB - Background: Direct measurement of blood flow output has been incorporated into ventricular assist devices (VADs), but long-term reliability of the additional device components has raised concerns regarding sensor drift and failure. As an alternative approach, the HeartMate II axial VAD (Thoratec Corp, Pleasanton, CA) estimates device flow output from power consumption and rotational speed of the device motor. This study evaluated the accuracy of HeartMate II flow estimation at the time of implantation. Methods: In 20 patients, intraoperative blood flow measurement of the HeartMate II flow estimator was compared with flow values obtained with an ultrasonic flow probe placed around the device outflow graft. Estimated and measured VAD flow data were simultaneously recorded and digitally stored while the device motor speed varied from 7,800 to 11,000 rpm and while achieving device flow outputs of 2 to 7 liters/min. Estimated and measured flows were compared using linear regression analyses and root mean square error. Results: HeartMate II flow estimation (FE) demonstrated a linear correlation with ultrasonic flow probe (FP) measurements: FE = 0.74 FP + 0.99 (R2 = 0.56, p = 0.0001). A root mean square error of 0.8 liters/min was observed between flow estimation and direct flow measurement and suggests a 15% to 20% difference at flows of 4 of 6 liters/min. Conclusions: These results suggest that HeartMate II flow estimation may be used to provide directional information for trend purposes rather than absolute values of device blood flow output. Patient management should include but not be limited to this information.

UR - http://www.scopus.com/inward/record.url?scp=58149231147&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=58149231147&partnerID=8YFLogxK

U2 - 10.1016/j.healun.2008.10.007

DO - 10.1016/j.healun.2008.10.007

M3 - Article

C2 - 19134529

AN - SCOPUS:58149231147

VL - 28

SP - 39

EP - 43

JO - Journal of Heart and Lung Transplantation

JF - Journal of Heart and Lung Transplantation

SN - 1053-2498

IS - 1

ER -