Endoscopic hydrodissection for saphenous vein harvesting: Remove no-touch in minimally invasive no touch?

Gallagher and colleagues 1 describe a minimally invasive no-touch (MINT) technique of saphenous vein (SV) harvesting using endoscopic hydrodissection.They compared MINT, traditional endoscopic (EVH), and open no-touch (NT) harvesting, assessing endothelial effects and nitric oxide (NO) production.Scanning electron microscopy showed an intact endothelium in MINT SVs, whereas the EVH endothelium was disrupted and NT endothelium irregular.Also, endothelial nitric oxide synthase activity (NOS)/NO production was reduced in EVH and NT versus MINT SVs.A previous study in which the authors used quantitative scanning electron microscopy showed an intact endothelium in NT versus conventional open SV harvesting (P < .01). 2 Preservation of perivascular fat is crucial for NT SV patency, because it reduces vascular damage, prevents spasm, provides mechanical support, 3 and is a source of NO (Figure 1). 4 Although MINT SV samples show an intact endothelium and the greatest NO production, the reduced NO production in the EVH and NT samples remains unexplained.The method measures total NOS activity, including inducible NOS, not specifically endothelial NOS.The lack of detail in the Methods regarding the original protocol described by Souza and colleagues 5 casts doubt on the NT data.Also, the use of hydrodissection and PlasmaLyte A invalidates the "NT" aspect of MINT.Although a reliable EVH NT technique is needed, the hydrodissection vein-harvesting technique from Gallagher and colleagues 1 may provide superior results with conventional EVH.Further studies are needed that compare the effects of NT, EVH, and hydrodissection vein-harvesting on SV structure, NO production, and patency.