[Early changes in the structure of venous grafts, their prevention and significance]

The authors investigated, using optic and electron microscopy, the course of regressive changes in smooth muscle cells of the media in venous grafts, in relation to various physical and chemical factors. They recorded the influence of a temperature of 4 degrees C and 22 degrees C, the influence of various types of crystalloid and colloid solutions and some pharmaceutical preparations. In previous work they found that, as a result of ischaemia, regressive changes take place in the smooth muscle cells of the media, while plasmatic structures of these cells and fibrillar structures of the venous wall remain intact. They provided evidence of the adverse effect of crystalloids, where the regressive changes can be detected already after 30 minutes. A protective effect on the nuclear structure is exerted by colloids, in particular a 6% solution of detoxicated haemoglobin. More favourable results were achieved at 22 degrees C. Some pharmacological preparations have a favourable effect on the preservation of the structure of cellular nuclei. The authors draw attention to the importance of these changes for clinical practice.