Published: January 12th, 2019
Normothermic ex situ heart perfusion (ESHP), preserves the heart in a beating, semi-physiologic state. When performed in a working mode, ESHP provides the opportunity to perform sophisticated assessments of donor heart function and organ viability. Here, we describe our method for myocardial performance evaluation during ESHP.
The current standard method for organ preservation (cold storage, CS), exposes the heart to a period of cold ischemia that limits the safe preservation time and increases the risk of adverse post-transplantation outcomes. Moreover, the static nature of CS does not allow for organ evaluation or intervention during the preservation interval. Normothermic ex situ heart perfusion (ESHP) is a novel method for preservation of the donated heart that minimizes cold ischemia by providing oxygenated, nutrient-rich perfusate to the heart. ESHP has been shown to be non-inferior to CS in the preservation of standard-criteria donor hearts and has also facilitated the clinical transplantation of the hearts donated after the circulatory determination of death. Currently, the only available clinical ESHP device perfuses the heart in an unloaded, non-working state, limiting assessments of myocardial performance. Conversely, ESHP in working mode provides the opportunity for comprehensive evaluation of cardiac performance by assessment of functional and metabolic parameters under physiologic conditions. Moreover, earlier experimental studies have suggested that ESHP in working mode may result in improved functional preservation. Here, we describe the protocol for ex situ perfusion of the heart in a large mammal (porcine) model, which is reproducible for different animal models and heart sizes. The software program in this ESHP apparatus allows for real-time and automated control of the pump speed to maintain desired aortic and left atrial pressure and evaluates a variety of functional and electrophysiological parameters with minimal need for supervision/manipulation.
While most aspects of cardiac transplantation have evolved significantly since the first heart transplant in 1967, cold storage (CS) remains the standard for donor heart preservation1. CS exposes the organ to a period of cold ischemia that limits the safe preservation interval (4–6 hours) and increases the risk of primary graft dysfunction2,3,4. Due to the static nature of CS, assessments of function or therapeutic interventions are not possible in the time between the organ procurement and transplantat....
All the procedures in this manuscript were performed in compliance with the guidelines of the Canadian Council on Animal Care and the guide for the care and use of laboratory animals. The protocols were approved by the institutional animal care committee of the University of Alberta. This protocol has been applied in female juvenile Yorkshire pigs between 35–50 kg. All individuals involved in ESHP procedures had received proper biosafety training.
1. Pre-surgical Preparations
At the start of the perfusion (in non-working mode), the heart will normally resume a sinus rhythm when the temperature of the system and perfusate approaches normothermia. When entering working mode, as the LA pressures are approaching the desired values, ejection on the Ao pressure tracing should be observed and the LA flow (a reflection of cardiac output) should increase gradually. In a Yorkshire pig model (35–50 kg) and a starting heart weight of 180–220 grams, the initial.......
Successful perfusion is defined according to the aims of the study; however, this should include uninterrupted ESHP for the desired amount of time and complete collection of the data on cardiac function during the perfusion. For this purpose, a few critical steps in the protocol must be followed.
The heart is an organ with high oxygen and energy demands, and minimizing the ischemic time before cannulation and perfusion is an important principle that must be followed. The process of procurement.......
This work was supported by grants from the Canadian National Transplant Research Program. SH is the recipient of a Faculty of Medicine and Dentistry Motyl Graduate Studentship in Cardiac Sciences. DHF is a recipient of a Collaborative Research Projects (CHRP) grant in aid from the National Sciences and Engineering Research Council and Canadian Institutes of Health Research.....
|Debakey-Metzenbaum dissecting scissors
|MAYO dissecting scissors
|Debakey straight vascular tissue forceps
|CUSHING Gutschdressing forceps
|JOHNSON needle holder
|DERF needle holder
|Vorse tubing clamp
|MORRIS ascending aorta clamp
|Surgical snare (tourniquet) set
|2-0 SILK black 12 X 18" strands
|3-0 PROLENE blue 18" PS-2 cutting
|Biomedicus pump drive (modified)
|Modified to allow remote electronic control of pump speed
|Membrane oxigenator D 905
|Tubing flow module
|PXL clamp-on flow sensor
|TruWave pressure transducer
|Intercept tubing 3/8" X 3/32" X 6'
|Intercept tubing 1/4" X 1/16" X 8'
|Heated/Refrigerated Bath Circulator
|ABL 800 FLEX Blood Gas Analyzer
|5F Ventriculr straight pigtail cathter
|5F AVANTI+ Sheath Introducer
|Emerald Amplatz Guidewire
|Dual chamber pace maker
|Surgical electrocautery device
|Medical oxygen tank
|Cabon dioxide tank
|Bovine serum albumin
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