Abstract Purpose: With 70 cm “cutter” valvulotomes for valvulotomy and an electronically steerable nitinol catheter to occlude venous tributaries with platinum coils, endovascular in situ saphenous vein (EISV) bypass can be safely perofrmed from within the saphenous vein. To determine whether EISV bypass could reduce hospital length of stay (LOS) and perioperative morbidity without compromising patency, another 53 EISV bypasses for limb salvage were performed. Methods: Tributary occlusion was accomplished with only fluoroscopic surveillance with a new, smaller, and more steerable silicone-tipped nitinol catheter. Results: Two (3.7%) wound complications occurred. The mean hospital LOS after operation was 4.2 days (range 2 to 29 days). All tributaries initially embolized remained occluded, and three “missed” arteriovenous fistulas were identified during follow-up extending to 15 month (mean 8.4 months). Eighty-eight percent (49 of 54) of phase II bypasses remained patent, whereas life-table analysis of all bypasses (phase I and II) was 77% (6999) at 24 months follow-up (mean 13.6 months). By comparison, 41 infrainguinal saphenous vein in situ bypasses with “classic” open techniques were performed concurrently. The mean postoperative LOS was 11.6 days (range 4 to 42 days), wound complications occurred in 24% (10) of patients, and two “missed” arteriovenous fistulas were identified during follow-up. Eighty-three percent (34 of 41) of bypasses remain patent at 24 months follow-up (mean 16.2 months). Conclusions: If EISV bypass long-term patency rates remain similar to classic in situ bypass patency results, the additional benefits of decreased hospital LOS, reduced wound-related complications, shortened recuperation, and therefore increased health care savings gives this endovascular technique strong consideration as the possible future operation for infrainguinal saphenous veins in situ bypass.