Video analysis of ex vivo beating hearts during preservation on the TransMedics® organ care system

Michelle Mendiola Pla; Silvia Berrettoni; Franklin H Lee; Giacomo Rozzi; Federica Marrano; Ryan T Gross; Amy Evans; David C Wendell; Paul Lezberg; Margherita Burattini; Francesco Paolo Lo Muzio; Lorenzo Fassina; Carmelo A Milano; Marie-Louise Bang; Dawn E Bowles; Michele Miragoli

doi:10.3389/fcvm.2023.1216917

Video analysis of ex vivo beating hearts during preservation on the TransMedics® organ care system

Front Cardiovasc Med. 2023 Jun 20:10:1216917. doi: 10.3389/fcvm.2023.1216917. eCollection 2023.

Authors

Michelle Mendiola Pla^#¹, Silvia Berrettoni^#², Franklin H Lee¹, Giacomo Rozzi², Federica Marrano², Ryan T Gross¹, Amy Evans³, David C Wendell⁴, Paul Lezberg⁵, Margherita Burattini^{2

6}, Francesco Paolo Lo Muzio², Lorenzo Fassina⁷, Carmelo A Milano¹, Marie-Louise Bang^{8

9}, Dawn E Bowles¹, Michele Miragoli^{2

9}

Affiliations

¹ Department of Surgery, Duke University Medical Center, Durham, NC, United States.
² Department of Medicine and Surgery, University of Parma, Parma, Italy.
³ Perfusion Services, Duke University Medical Center, Durham, NC, United States.
⁴ Duke Cardiovascular Magnetic Resonance Center, Duke University Medical Center, Durham, NC, United States.
⁵ TransMedics, Inc., Andover, MA, United States.
⁶ Department of Surgical Sciences, Dentistry, and Maternity, University of Verona, Verona, Italy.
⁷ Department of Electrical, Computer, and Biomedical Engineering, University of Pavia, Pavia, Italy.
⁸ Institute of Genetic and Biomedical Research (IRGB), National Research Council (CNR), Milan Unit, Milan, Italy.
⁹ IRCCS Humanitas Research Hospital, Milan, Italy.

^# Contributed equally.

Abstract

Background: Reliable biomarkers for assessing the viability of the donor hearts undergoing ex vivo perfusion remain elusive. A unique feature of normothermic ex vivo perfusion on the TransMedics® Organ Care System (OCS™) is that the donor heart is maintained in a beating state throughout the preservation period. We applied a video algorithm for an in vivo assessment of cardiac kinematics, video kinematic evaluation (Vi.Ki.E.), to the donor hearts undergoing ex vivo perfusion on the OCS™ to assess the feasibility of applying this algorithm in this setting.

Methods: Healthy donor porcine hearts (n = 6) were procured from Yucatan pigs and underwent 2 h of normothermic ex vivo perfusion on the OCS™ device. During the preservation period, serial high-resolution videos were captured at 30 frames per second. Using Vi.Ki.E., we assessed the force, energy, contractility, and trajectory parameters of each heart.

Results: There were no significant changes in any of the measured parameters of the heart on the OCS™ device over time as judged by linear regression analysis. Importantly, there were no significant changes in contractility during the duration of the preservation period (time 0-30 min, 918 ± 430 px/s; time 31-60 min, 1,386 ± 603 px/s; time 61-90 min, 1,299 ± 617 px/s; time 91-120 min, 1,535 ± 728 px/s). Similarly, there were no significant changes in the force, energy, or trajectory parameters. Post-transplantation echocardiograms demonstrated robust contractility of each allograft.

Conclusion: Vi.Ki.E. assessment of the donor hearts undergoing ex vivo perfusion is feasible on the TransMedics OCS™, and we observed that the donor hearts maintain steady kinematic measurements throughout the duration.

Keywords: biomarker; cardiac transplantation; ex vivo perfusion; kinematics; normothermic; video.

Grants and funding

This work was supported by the National Recovery and Resilience Plan (NRRP), Mission 4 Component 2 Investment 1.5 - Call for tender No. 3277 of 30/12/2021 of the Italian Ministry of University and Research funded by the European Union - NextGenerationEU (ECS00000033) to MM and the ERA PerMed funded project LVADStrat (ERAPERMED2018-271) to MLB. Funding for the surgeries was provided by the Duke Division of Cardiothoracic Surgery and TransMedics, Inc. MMP is supported by the National Institutes of Health (T32HL007101). The authors declare that this study received funding from TransMedics, Inc. The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article or the decision to submit it for publication.