Experimental Studies on the Endothelium Ultrastructure of Heart Capillaries under Moderate (28–30°) and Deep (22–24°) Hypothermia without Perfusion

Impact of Graded Hypothermia on Coagulation and Fibrinolysis

“…It has been found that in cardiopulmonary bypass thrombomodulin plasma level, which is considered to be a marker of endothelial cell damage, was increased more in hypothermia than in normothermia [20]. Moreover, Kazanskaya et al have found under electron microscopy that temperature <30 C without perfusion produces adaptive changes in myocardiac capillary endothelial cells [29].…”

Ultrastructure of Myocardial Capillary Endothelium in Children with Congenital Heart Disease

“…Our findings indicate that all morphological variants of EC, previously detected in animal experiments [6] and in cardiovascular patients aged more than 1 year [5], were present in the right atrial exchange capillary endothelium of infants aged under 1 year. However, precise classification of EC appurtenance to one of the 5 morphological variants is difficult.…”

“…Intraoperative changes in EC forming the inner lining of the right atrial capillaries, were evaluated as described previously [6]. The profiles of EC lining all exchange capillaries in the section, were estimated at three stages of the operation at the initial magnification ×10,000.…”

Ultrastructural Organization of Capillaries in Various Compartments of the Dog Heart in Artificial Immersion Hypothermia

“…However the initial percentage of dark cells in the right-atrial capillary endothelium was significantly (p<0.05) higher than in the left ventricle. Previous data, demonstrating the presence of the most pronounced transcytosis system in the dark EC (of all EC variants) [11], suggest that low adaptation of atrial capillaries to realization of convection transport regulated by the capillary geometry, can be compensated for by a high level of dissipation transfer of macromolecules in them. The conditions of deep hypothermia are inessential for the perfusion capacity of ventricular capillaries, while in the atrium hypothermia stimulated exclusion of rather many capillaries from the bloodflow.…”

“…Total number of EC profiles, forming the inner lining of capillaries, was evaluated at the initial ×10 000 magnification. The percentage of each of the five morphological variants of cells (main type, clear, dark, edematous, and hyperosmium) was evaluated in the total EC population [11]; at least 100 cells per animal were analyzed. The geometrical characteristics of rightatrial and left-ventricular capillaries were estimated by the formulas suggested previously [14) in modification [3] suggested for morphometrical analysis of components of the capillary system of the organ.…”