Preserved endothelial integrity and nitric oxide synthase in saphenous vein grafts harvested by a 'no-touch'...

Area of Science:

• Cardiovascular Surgery
• Vascular Biology
• Surgical Techniques

Background:

• Saphenous veins are primary grafts for coronary artery bypass surgery.
• Conventional harvesting causes significant vein damage, leading to high graft occlusion rates (up to 30% at 1 year).
• Endothelial integrity and nitric oxide synthase (NOS) are critical for graft patency.

Purpose of the Study:

• To compare endothelial integrity and NOS in saphenous veins harvested using a novel "no-touch" technique versus conventional methods.
• To evaluate the impact of harvesting technique on key factors influencing graft patency.

Main Methods:

• Immunohistochemistry was used to assess endothelial integrity.
• Histochemistry and autoradiography identified nitric oxide synthase (NOS) distribution.
• Human saphenous veins harvested by both conventional and "no-touch" techniques were analyzed.

Main Results:

• No-touch grafts exhibited significantly better endothelial lining preservation (73%) compared to conventional grafts (52%; P=0.04).
• Reduced NOS availability was observed in conventional grafts.
• No-touch grafts retained NOS in the adventitial vasa vasorum, which are often removed during conventional harvesting.

Conclusions:

• Conventional saphenous vein harvesting removes sites crucial for nitric oxide release in vivo.
• "No-touch" harvesting preserves these sites, offering potential for improved coronary artery bypass graft patency.
• The findings suggest the "no-touch" technique may reduce graft occlusion rates.