Extracorporeal driveline vibrations to detect left ventricular assist device thrombosis - A porcine model study

Didrik Lilja; Itai Schalit; Andreas Espinoza; Tom Nilsen Hoel; Guttorm Larsen; Fred-Johan Pettersen; Per Steinar Halvorsen

doi:10.1016/j.healun.2023.08.022

Extracorporeal driveline vibrations to detect left ventricular assist device thrombosis - A porcine model study

J Heart Lung Transplant. 2024 Jan;43(1):111-119. doi: 10.1016/j.healun.2023.08.022. Epub 2023 Sep 4.

Authors

Didrik Lilja¹, Itai Schalit², Andreas Espinoza², Tom Nilsen Hoel³, Guttorm Larsen², Fred-Johan Pettersen⁴, Per Steinar Halvorsen⁵

Affiliations

¹ The Intervention Centre, Division of Technology and Innovation, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway. Electronic address: didlil@ous-hf.no.
² The Intervention Centre, Division of Technology and Innovation, Oslo University Hospital, Oslo, Norway.
³ Department of Cardiothoracic Surgery, Oslo University Hospital, Oslo, Norway.
⁴ Department of Clinical and Biomedical Engineering, Oslo University Hospital, Oslo, Norway; Department of Physics, University of Oslo, Oslo, Norway.
⁵ The Intervention Centre, Division of Technology and Innovation, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway.

PMID: 37673384
DOI: 10.1016/j.healun.2023.08.022

Abstract

Background: Pump thrombosis (PT) and related adverse complications contributed to the HeartWare Ventricular Assist Device (HVAD) market withdrawal. Many patients still receive lifelong support, with deficient PT surveillance based on pump power trends. Analysis of pump vibrations is better for detecting PT. Here, we investigated the feasibility of an extracorporeal accelerometer to detect PT from pump vibrations propagated out on the driveline.

Methods: In a porcine HVAD model (n = 6), an accelerometer was attached to the pump as a reference and another to the driveline for comparisons of signals. In total, 59 thrombi were injected into the heart to induce PT, followed by intermittent thrombus washout maneuvers. Signals were compared visually in spectrograms and quantitatively in third harmonic saliences (S_3H) by correlation analysis. Receiver operating characteristic curves expressed the method's outcome in sensitivity vs specificity, with the overall diagnostic performance in the area under the curve (AUC) score.

Results: Five experiments had good driveline signal strength, with clear spectrographic relationships between the 2 accelerometers. Third harmonic driveline vibrations were visible 20 vs 30 times in the reference. The comparison in S_3H showed a strong correlation and yielded an AUC of 0.85. Notably, S_3H proved robust regarding noise and false PT detections.

Conclusions: An extracorporeal accelerometer on the driveline can be a readily available method for accurate HVAD PT detection before an accelerometer integration with left ventricular assist device is feasible.

Keywords: LVAD pump thrombosis; accelerometer; detection; driveline; vibrations.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Heart Failure*
Heart-Assist Devices* / adverse effects
Humans
Retrospective Studies
Swine
Thrombosis* / diagnosis
Thrombosis* / epidemiology
Thrombosis* / etiology
Vibration