The saphenous vein remains the most commonly used conduit in coronary artery bypass surgery, yet its main limitation continues to be mid- to long-term graft failure. The no-touch (NT) technique—based on harvesting the saphenous vein as a pedicled conduit, preserving the adventitia and often including surrounding subcutaneous tissue—seeks to mitigate this limitation by minimizing perivascular tissue injury, preserving the vasa vasorum, and reducing endothelial damage, with the hypothesis that these mechanisms may prolong long-term graft patency. However, the publication of recent trials with variable results has reignited debate regarding its true clinical value.

The analysis included 8 prospective randomized studies with a similar design (n = 4286). The primary endpoint was saphenous vein graft failure, while secondary endpoints included mortality, major adverse cardiovascular events (MACCE), and leg wound complications. At a weighted mean follow-up of 3.7 years, NT harvesting was associated with a lower incidence of graft failure (IRR = 0.70), with no significant differences in mortality or MACCE, but with a higher rate of leg wound complications (IRR = 1.73).

COMMENTARY:

Based on these findings, several practical and clinically relevant conclusions can be drawn. First, NT harvesting demonstrates superiority with respect to the primary endpoint, as it improves graft patency and reduces the incidence of vein graft failure. This effect is consistent and statistically robust, with an approximately 30% relative reduction in graft failure rates compared with conventional harvesting. Importantly, statistical heterogeneity was negligible, and multiple sensitivity analyses confirmed the stability of the results, reinforcing the concept that saphenous vein performance is influenced, at least in part, by the way the conduit is harvested and handled.

The meta-analysis did not identify differences in mortality or MACCE between the two techniques. This finding is likely related to the relatively short duration of follow-up, the limited number of clinical events, and the fact that most included trials were designed and powered to detect differences in graft patency rather than hard clinical outcomes.

The potential benefit of the no-touch technique is achieved at the cost of a higher incidence of local complications at the harvest site. This represents a clinically relevant drawback, as leg wound complications may negatively affect patient recovery, satisfaction, and potentially length of hospital stay.

Among the limitations acknowledged by the authors is the heterogeneity across included trials in terms of center experience, surgical technique, definitions of graft patency, and postoperative management protocols. Although graft failure was defined in a relatively homogeneous manner, secondary clinical outcomes were not consistently reported across studies, limiting the strength of their interpretation. Nevertheless, statistical heterogeneity was low, and sensitivity analyses supported the robustness of the main findings. Additional potential sources of bias include incomplete follow-up, lack of blinding, and the disproportionate weight of one of the eight included trials.

In conclusion, this meta-analysis places the no-touch saphenous vein technique in a favorable position from the standpoint of randomized evidence for reducing vein graft failure. At the same time, it clearly highlights that its current implementation carries a tangible cost in terms of increased harvest-site complications. Further protocol refinement and technical optimization may be required to reduce local morbidity. Importantly, additional studies with longer follow-up are needed to better define the impact of improved graft patency on long-term clinical outcomes.

REFERENCE:

Sandner S, Hirofuji A, Mantaj P, et al. Outcomes of No-Touch Vs Conventionally Harvested Saphenous Veins for Coronary Artery Bypass Surgery: A Meta-Analysis of Randomized Trials. Eur J Cardiothorac Surg. 2025;67(9):ezaf297. doi:10.1093/ejcts/ezaf297.