Open AccessHeartWare HVAD Flow Estimator Accuracy for Left and Right Ventricular Support
Author(s) -
Andrew F. Stephens,
Martin Mapley,
Eric Wu,
John F. Fraser,
Ulrich Steinseifer,
Nicole Bartnikowski,
Shaun D. Gregory
Publication year - 2020
Publication title -
asaio journal
Language(s) - English
Resource type - Journals
eISSN - 1538-943X
pISSN - 1058-2916
DOI - 10.1097/mat.0000000000001247
Subject(s) - pulsatile flow , waveform , hematocrit , flow (mathematics) , estimator , materials science , volumetric flow rate , cardiology , mathematics , mechanics , medicine , physics , statistics , voltage , quantum mechanics
This study investigated the accuracy of the HeartWare HVAD flow estimator for left ventricular assist device (LVAD) support and biventricular assist device (BiVAD) support for modes of reduced speed (BiVAD-RS) and banded outflow (BiVAD-B). The HVAD flow estimator was evaluated in a mock circulatory loop under changes in systemic and pulmonary vascular resistance, heart rate, central venous pressure, and simulated hematocrit (correlated to viscosity). A difference was found between mean estimated and mean measured flow for LVAD (0.1 ± 0.3 L/min), BiVAD-RS (-0.1 ± 0.2 L/min), and BiVAD-B (0 ± 0.2 L/min). Analysis of the flow waveform pulsatility showed good correlation for LVAD (r2 = 0.98) with a modest spread in error (0.7 ± 0.1 L/min), while BiVAD-RS and BiVAD-B showed similar spread in error (0.7 ± 0.3 and 0.7 ± 0.2 L/min, respectively), with much lower correlation (r2 = 0.85 and r2 = 0.60, respectively). This study demonstrated that the mean flow error of the HVAD flow estimator is similar when the device is used in LVAD, BiVAD-RS, or BiVAD-B configuration. However, the instantaneous flow waveform should be interpreted with caution, particularly in the cases of BiVAD support.