Background: The deep veins (DV) of the thigh have proven to be versatile autogenous conduits for arterial reconstruction. Harvesting DV poses a theoretical risk of compromising venous outflow of the limb, which could predispose to chronic venous morbidity. The purpose of this study was to define the late incidence of chronic venous insufficiency (CVI) and to characterize the long-term alterations in venous physiology after DV harvest. Methods: Since 1991, 269 patients have undergone arterial reconstructions using DV at our facility. Patients with DV harvest at least 43 months prior to the study (n = 151) were eligible for inclusion. Eighty-nine patients were excluded (deceased = 70; lost to follow-up = 19). Forty-six patients who declined formal testing were queried by phone for signs and symptoms of CVI. The current study presents a case-control series of 16 patients (27 limbs) after DV harvest and six age- and gender-matched control patients (12 limbs) who underwent examination and venous testing. Results: At a mean follow-up of 70.1 ± 5.6 months, 23 of 27 limbs (85.2%) had no significant CVI (CEAP C0 to C2). Four limbs (14.8%) had significant venous morbidity (C3 to C6), including edema alone (C3; n = 2 limbs), edema with skin changes (C4; n = 1 limb), and a healed venous ulceration (C5; n = 1 limb). APG testing confirmed relative venous outflow obstruction after DV harvest (mean outflow fraction: harvested limbs = 38.4 ± 3.9% vs control limbs = 51.7 ± 4.3%; P = .04). Despite the relative outflow obstruction, the mean VFI was not significantly different between harvested and control limbs (harvested limbs = 1.08 ± 0.15% vs control limbs = 0.77 ± 0.16%; P = .19). DV harvest resulted in no significant changes in calf ejection fraction (harvested limbs = 67.4 ± 6.4% vs control limbs = 86.8 ± 9.5%; P = .09) or residual volume fraction measured (harvested limbs = 32.3 ± 6.4% vs control limbs = 47.7 ± 11.6%; P = .22). Of the 46 patients interviewed by phone, five (10.9%) reported bilateral amputations, seven (15.2%) reported chronic edema in their harvested limbs (C3), and 34 (73.9%) reported no signs of CVI in their harvested limbs (C0). Conclusions: Deep vein harvest produces few symptoms of chronic venous insufficiency, and venous ulceration is infrequent. Despite relative venous outflow obstruction, noninvasive indices of chronic venous insufficiency on APG are often normal, suggesting that the risk of developing venous ulceration is low in the majority of patients after DV harvest.