Comparing the Effects of Krebs Plus Verapamil Solution on Endothelial Function of Harvested Human Greater Saphenous Vein with Heparinized Blood, an Invitro Study

Storage solutions to improve grafts preservation and longevity in coronary artery bypass grafting surgery: hype or hope?

PURPOSE OF REVIEW

Saphenous vein grafts (SVGs) remain the most-commonly used conduits for coronary artery bypass grafting (CABG).Significant rates of vein graft failure (VGF) remain a limitation of their use as this diminishes the long-term benefits of CABG. The choice of intraoperative SVGs preservation solution is believed to have an impact on graft patency; however, the superiority of one solution over the others remains in question.

RECENT FINDINGS

In the present review, we describe the pathophysiological mechanisms underlying the different phases of VGF. We also reviewed the most recent literature comparing and evaluating the efficacy of various storage solutions. These include heparinized saline, autologous heparinized blood, buffered solutions, and crystalloid cardioplegia.

SUMMARY

It is clear that the composition of the SVGs storage solution has an impact on vessel wall structure and function. There is a lack of translational and clinical research on the topic; thus, conclusions cannot be drawn regarding the superiority of one solution over the others in terms of VGF. Future research needs to be conducted to address this gap in the literature in order to make meaningful evidence-based recommendations on intraoperative graft storage.

[Method of optimal hydraulic dilatation of venous conduits for coronary artery bypass grafting]

Hydraulic dilatation is used in everyday cardiac surgical practice for assessment of leak-proofness and prevention of spasm of autovenous shunts. The classical technique envisages manual high-pressure solution injection, which exerts a negative effect on venous conduits and is one of the causes of incompetence of shunts in the postoperative period. Limiting pressure during hydraulic dilatation is necessary to minimize morphological changes and preserve functional viability of venous conduits. The purpose of the present study was to develop and assess efficacy of a standardized methodology of controlled hydraulic dilatation of venous conduits. We worked out an original technique of controlled hydraulic dilatation of venous conduits under perfusion pressure of artificial circulation. This was followed by assessing morphological changes and functional viability of venous segments after controlled hydraulic dilatation as compared with veins after conventional uncontrolled hydraulic dilatation and the control intact veins. Uncontrolled hydraulic dilatation was accompanied by endothelial damage (p<0.05), multiple conduit wall tears (p<0.05) according to the findings of light microscopy, leading to a significant decrease in the functional vitality of the venous conduit (a decreased reaction to hyperpotassium solution, phenylephrine, acetylcholine and sodium nitroprusside (p<0.05) according to the findings of biophysical examination. Our original technique of controlled hydraulic dilatation of venous conduits under perfusion pressure of artificial circulation made it possible not only to evaluate leak-proofness of the vessel but also to achieve comparable to the control segments parameters of structural integrity of the venous wall and functional viability of the conduit. Thus, using the developed method of controlled hydraulic dilatation makes it possible to minimize morphofunctional alterations in venous conduits, influencing the function of autovenous shunts.