Abstract
Aims: The study aimed to compare the scanning electron microscopic gradings of the endothelium and calcium depositions between proximal, under-bridging, distal, and control segments of the coronary artery with myocardial bridge (MB). Methods: The autopsy of 45 adult hearts with MB among the 243 cases was collected from North Okkalapa General and Teaching Hospital, Yangon. Then, the length and thickness of the MB were measured. The endothelial gradings and elements composition of each specimen was examined by a scanning electron microscope (Phenom Pro X) with energy dispersion X-ray spectrometry (EDS) operated at 15 kV. Results: In the present study, 45 bridges (18.5%) were observed among the 243 hearts. They were located on the left anterior descending artery (LAD) in all cases (100%). The mean length of the MB was 18.3 ± 11.7 mm (range 1.5–59 mm). The mean thickness of the MB was 2.8 ± 1.5 mm (range 1–6.3 mm). In comparing endothelial cell gradings and calcium deposition of four segments, the proximal segment was significantly different from the under-bridging segment, distal segment, and control segment. The under-bridging segment was significantly different gradings from the distal segment (p less than 0.05). Conclusion: The proximal segment was the most endothelial damage site due to hemodynamic effect of the MB. The under-bridging segment was the least endothelial damage site which might be due to the atheroprotective effect of the MB in under segment.
Highlights
The myocardial muscle fiber over the segment of the coronary artery was known as a “myocardial bridge” (MB)
In comparing endothelial cell gradings and calcium deposition of four segments, the proximal segment was significantly different from the under-bridging segment, distal segment, and control segment
The under-bridging segment was the least endothelial damage site which might be due to the atheroprotective effect of the MB in under segment
Summary
The myocardial muscle fiber over the segment of the coronary artery was known as a “myocardial bridge” (MB). The common affected location of MB was the middle parts of the left anterior descending artery (LAD) [1,2,3,4]. The frequency of MB was 4.7– 86% [5, 6]. The proximal segment of MB was more prone to arteriosclerosis [7]. Edorium Journal of Anatomy and Embryology, Vol 7; 2020. MB was not associated with atherosclerosis changes of the coronary artery. Metaanalysis review suggested that more studies need to find out the association between myocardial bridging and myocardial infarct, and sudden death [8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
