Retrograde dye perfusion of the proximal aorta - A postmortem technical study

Heliyon. 2022 Dec 21;8(12):e12475. doi: 10.1016/j.heliyon.2022.e12475. eCollection 2022 Dec.

Abstract

Introduction: Multiple cardiovascular conditions can lead to unexpected fatality, which is defined as sudden cardiac death. One of these potentially underlying conditions is aortic regurgitation, which can be caused by discrete changes of the geometry of the proximal aorta. To analyze aortic valve competency and furthermore to elucidate underlying pathological alterations of the coronary arteries and the vasa vasorum a perfusion method to simulate a diastolic state was designed.

Material and methods: A postmortem approach with retrograde perfusion of the ascending aorta with methylene blue was applied to three bodies. The procedure comprised cannulation of the brachiocephalic trunk, clamping of the aortic arch between brachiocephalic trunk and left carotid artery, infusion of 250 ml of methylene blue, and optical clearing of the superficial tissue layers after perfusion. Organs were examined directly following perfusion and after optical clearing.

Results: Assessment and visualization of aortic valve competency and the vasa vasorum were possible in all three instances. Visualization of the coronary perfusion was impaired by postmortem thrombus formation. Optical clearing did not provide additional information.

Discussion: The method presented here is a time- and cost-efficient way of visualizing aortic valve competency and the vasa vasorum. The visualization of the vasa vasorum highlights the potential of this method in basic research on diseases of the great arteries and coronaries. However, for a time-efficient functional analysis of the coronaries, other methods must be applied.

Keywords: Aortic valve competency; Coronary perfusion; Methylene blue perfusion; Optical clearing; Sudden cardiac death; Vasa vasorum.