Contrast Microsphere Destruction by a Continuous Flow Ventricular Assist Device: An in Vitro Evaluation Using a Mock Circulation Loop

David G. Platts, Nicole Bartnikowski, Shaun D. Gregory, Gregory M. Scalia, John F. Fraser

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Objectives. Transthoracic echocardiography (TTE) is fundamental in managing patients supported with ventricular assist devices (VAD). However imaging can be difficult in these patients. Contrast improves image quality but they are hydrodynamically fragile agents. The aim was to assess contrast concentration following passage through a VAD utilising a mock circulation loop (MCL). Methods. Heartware continuous flow (CF) VAD was incorporated into a MCL. Definity® contrast was infused into the MCL with imaging before and after CF-VAD. 5 mm2 regions of interest were used to obtain signal intensity (decibels), as a surrogate of contrast concentration. Results. Four pump speeds revealed significant reduction in contrast signal intensity after CF-VAD compared to before CF-VAD (all p<0.0001). Combined pre- and postpump data at all speeds showed a 22.2% absolute reduction in contrast signal intensity across the CF-VAD (14.8 ± 0.8 dB prepump versus 11.6 ± 1.4 dB postpump; p<0.0001). Mean signal intensity reduction at each speed showed an inverse relationship between speed and relative reduction in signal intensity. Conclusion. Contrast microsphere transit through a CF-VAD within a MCL resulted in significant reduction in signal intensity, consistent with destruction within the pump. This was evident at all CF-VAD pump speeds but relative signal drop was inversely proportional to pump speed.

Original languageEnglish
Article number4907898
Number of pages10
JournalBioMed Research International
Volume2017
DOIs
Publication statusPublished - 1 Jan 2017
Externally publishedYes

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