title: Achieving 12 Hour Normothermic Ex Situ Heart Perfusion: An Experience of 40 Porcine Hearts.
abstract: Although total body perfusion with extracorporeal life support (ECLS) can be maintained for weeks, individual organ perfusion beyond 12 hours has yet to be achieved clinically. Normothermic ex situ heart perfusion (ESHP) offers the potential for prolonged cardiac preservation. We developed an ESHP system to study the effect of perfusate variables on organ preservation, with the ultimate goal of extending organ perfusion for ≥24 hours. Forty porcine hearts were perfused for a target of 12 hours. Hearts that maintained electromechanical activity and had a <3× increase in vascular resistance were considered successful preservations. Perfusion variables, metabolic byproducts, and histopathology were monitored and sampled to identify factors associated with preservation failure. Twenty-two of 40 hearts were successfully preserved at 12 hours. Successful 12 hour experiments demonstrated lower potassium (4.3 ± 0.8 vs. 5.0 ± 1.2 mmol/L; p = 0.018) and lactate (3.5 ± 2.8 vs. 4.5 ± 2.9 mmol/L; p = 0.139) levels, and histopathology revealed less tissue damage (p = 0.003) and less weight gain (p = 0.072). Results of these early experiments suggest prolonged ESHP is feasible, and that elevated lactate and potassium levels are associated with organ failure. Further studies are necessary to identify the ideal perfusate for normothermic ESHP.
authors.affiliation: From the *Extracorporeal Life Support Laboratory, Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan; †Department of Surgery, Columbia University Medical Center, New York, New York; ‡In Vivo Animal Core, Unit for Laboratory Animal Medicine, University of Michigan Medical School, Ann Arbor, Michigan; §Advanced Platform Technology Center, VA Ann Arbor Health Care System, Ann Arbor, Michigan; ¶Department of Surgery, Section of Transplant Surgery, and ‖Department of Pediatric Cardiology, University of Michigan Health Systems, Ann Arbor, Michigan.
authors.forename: John M
authors.initials: JM
authors.lastname: Trahanas
authors.forename: Lucas J
authors.initials: LJ
authors.lastname: Witer
authors.forename: Fares
authors.initials: F
authors.lastname: Alghanem
authors.forename: Benjamin S
authors.initials: BS
authors.lastname: Bryner
authors.forename: Amit
authors.initials: A
authors.lastname: Iyengar
authors.forename: Jacob R
authors.initials: JR
authors.lastname: Hirschl
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Hoenerhoff
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Potkay
authors.forename: Robert H
authors.initials: RH
authors.lastname: Bartlett
authors.forename: Alvaro
authors.initials: A
authors.lastname: Rojas-Pena
authors.forename: Gabe E
authors.initials: GE
authors.lastname: Owens
authors.forename: Martin L
authors.initials: ML
authors.lastname: Bocks
mesh_terms: D000818:Animals; D016027:Heart Transplantation; D009926:Organ Preservation / Q000379:methods*; D010477:Perfusion / Q000379:methods*; D013552:Swine; D013997:Time Factors