Thread-like structures in the aorta and coronary artery of swine

We report on the observation of thread-like structures, which run inside the aorta, and coronary artery of the swine. Although the current knowledge of animal anatomy and physiology does not explain such structure, it is found that these intravascular thread-like structures were attached with clotting mass in the left ventricle of the heart. These structures were running along the inside of the aorta and coronary artery. These structures were semitransparent when it was washed with saline. The thickness of these structures varied from 100 to 300um. We considered that these structures were morphologically similar intravascular Bonghan duct (IBHD). More extensive investigation is necessary to elucidate whether intravascular thread-like structure are truly Bonghan duct or material of clot.