Methodology of asystolic donor heart’s condition study in an experiment using small laboratory animals

In transplantation, there has always been an acute problem of the discrepancy between the number of donor organs and the number of recipients, including donor hearts. There are various ways to increase the pool of donor organs, one of them is the use of asystolic or non-heart-beating donors. Due to poor myocardial tolerance of ischemia during the asystole period, as well as because of the difficulties in diagnosing cardiac diseases of the asystolic donor, which can be contraindication to transplantation. Therefore, an in-depth study of the state of the myocardium in asystolic donors is required. Currently, there is no generally accepted protocol for working with asystolic heart donors. This protocol should include methods of heart conditioning and assessing of myocardium state. For its development we need more experimental and preclinical studies. A protocol for such a study is proposed. The modeling of an asystolic donor using rats is described on the basis of experimental work carried out by a team of authors. The article describes the following technical aspects: anesthetic guidance, asystole detection criterion, maintaining the rat body temperature in accordance with the human body temperature during cardiac arrest, surgical aspects of performing the main experimental model. The Langendorff model of isolated cardiac perfusion was chosen as the main model for assessing the state of the myocardium of a small laboratory animal. Intra-left ventricular pressure, volume of coronary blood flow, heart rate and the presence of post-reperfusion arrhythmias were selected as criteria for assessing the state of donor hearts. Assessment of the volume of damage to the donor heart is carried out using triphenyltetrazolium chloride staining of the donor organ.

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