Evaluation in a porcine wound model and long-term clinical assessment of an autologous heterogeneous skin construct used to close full-thickness wounds.

Acute and chronic wounds involving deeper layers of the skin are often not adequately healed by dressings alone and require therapies such as skin grafting, skin substitutes, or growth factors. Here we report the development of an autologous heterogeneous skin construct (AHSC) that aids wound closure. AHSC is manufactured from a piece of healthy full-thickness skin. The manufacturing process creates multicellular segments, which contain endogenous skin cell populations present within hair follicles. These segments are physically optimized for engraftment within the wound bed. The ability of AHSC to facilitate closure of full thickness wounds of the skin was evaluated in a swine model and clinically in 4 patients with wounds of different etiologies. Transcriptional analysis demonstrated high concordance of gene expression between AHSC and native tissues for extracellular matrix and stem cell gene expression panels. Swine wounds demonstrated complete wound epithelialization and mature stable skin by 4 months, with hair follicle development in AHSC-treated wounds evident by 15 weeks. Biomechanical, histomorphological, and compositional analysis of the resultant swine and human skin wound biopsies demonstrated the presence of epidermal and dermal architecture with follicular and glandular structures that are similar to native skin. These data suggest that treatment with AHSC can facilitate wound closure.

Endoscopic versus open great saphenous vein harvesting for femoral to popliteal artery bypass.

OBJECTIVE: Conflicting data exist on outcomes of open vein harvest (OVH) and endoscopic vein harvest (EVH) for infrainguinal bypass. The purpose of this study was to compare outcomes between OVH and EVH in femoral to popliteal artery bypasses. METHODS: A retrospective review was performed of all patients undergoing common femoral to popliteal artery bypass with great saphenous vein between January 1997 and June 2014. Bypasses using arm or composite vein were excluded, as were those performed for popliteal artery aneurysms or trauma. Harvest was typically performed by dedicated surgical assistants. Patients were analyzed by either OVH or EVH of vein. The primary outcome was primary patency. Secondary outcomes included assisted primary and secondary patency and major wound complications. Statistical analysis was performed for categorical and continuous variables with life-table and survival statistics for long-term outcomes. RESULTS: In the study time, 505 patients underwent femoral-popliteal bypass; 262 patients and 280 limbs met the inclusion criteria. OVH was performed on 194 (69%) limbs and EVH on 86 (31%). There was no significant difference between the groups in terms of demographics, comorbidities, and preoperative Rutherford classification. Mean follow-up was 34 months. Six of 13 operators (46%) used both harvest techniques. At 5 years, OVH demonstrated higher rates of primary patency compared with EVH (62.8% vs 47%; P = .006) and higher rates of assisted primary patency (81.2% vs 64.3%; P = .003). Secondary patency was not significantly different between groups. The average number of graft interventions was less frequent with EVH, although this trend was not statistically significant (0.1 OVH vs 0.3 EVH; P = .1). EVH also had a lower rate of major wound complications per limb (n = 16; 8% OVH vs 0% EVH; P = .004). CONCLUSIONS: OVH was associated with superior primary and assisted primary patencies compared with EVH at 5 years, yet OVH was associated with higher wound complications. Surgeons should weigh the risk of wound complications vs decreased primary and primary assisted patency when deciding which method to use for vein harvest.

Outcome of peripheral venous reconstructions during tumor resection.

OBJECTIVE: Peripheral venous reconstruction surgery may be necessary for appropriate oncologic resection; however, the operative approach and surgical outcomes are not well described. We report our experience with these complex reconstructions to identify best practice. METHODS: We retrospectively reviewed all adult patients who underwent peripheral vein reconstruction for tumor resection at Mayo Clinic, Rochester (2000-2015). Patients were classified into three subgroups by the location: iliac (IL), lower extremity (LE), and upper extremity (UE). Location, type of reconstruction, operative morbidity, as well as long-term patency, limb salvage, recurrence-free survival, and overall survival were recorded. RESULTS: We identified 27 patients (11 women and 16 men), with a mean age of 55 ± 15 years, who underwent 28 operations involving vein reconstruction during tumor resection. One patient underwent two vascular reconstructions for recurrent malignant fibrous histiocytoma. Concomitant artery reconstruction was required in 16 (57%). The most commonly treated tumors were rectal cancer (n = 4) and liposarcoma (n = 3). Reconstructions were IL in 19 (68%), LE in 6 (21%), and UE in 3 (11%). Venous reconstructions consisted of 7 vein grafts (25%), 17 polytetrafluoroethylene prosthetic grafts (61%), 1 cryograft (4%), and 3 isolated patch angioplasties (11%). Two additional patch angioplasty procedures were performed in conjunction with vein grafts (1 polytetrafluoroethylene, 1 vein graft). There were no 30-day deaths. The mean hospital length of stay was 13.5 ± 10.5 days. Medications prescribed at discharge were aspirin in 15 patients (54%) and warfarin in 16 (57%). Surgical complications included renal failure (n = 5), respiratory complication (n = 3), surgical site infection (n = 5), graft infection (n = 3), and lymph leak (n = 5). The median follow-up was 4.4 years (range, 17 days-14.1 years). At 2 and 5 years, overall primary patency was 61% (95% confidence interval [CI], 41%-87%) and 61% (95% CI, 36%-87%), respectively, and overall freedom from graft thrombosis was 87% (95% CI, 69%-100%) and 87% (95% CI, 64%-100%), respectively. Graft thrombosis occurred in five patients (18%; 4 IL, 1 LE), of which four were prosthetic and one was a patch site. These were managed by thrombolysis (n = 1), thrombectomy (n = 1), and medical management (n = 3). Two patients (7.1%) underwent ipsilateral amputation at 3 and 314 days for compartment syndrome and metastatic pain. The overall survival rate was 74% (95% CI, 50%-87%) at 2 years and 56% (95% CI, 32%-75%) at 5 years. Death was predominantly from cancer-associated morbidities. Overall recurrence-free survival was 75% (95% CI, 57%-97%) at 2 years and 56% (95% CI, 31%-92%) at 5 years. CONCLUSIONS: In selected patients fit for advanced tumor resection, reconstruction of IL and extremity veins is a safe and durable, with excellent limb salvage. Vein and prosthetic reconstructions both appear effective; however, infectious complications and graft thrombosis remain important complications when selecting a prosthetic conduit.

Impact of femoropopliteal endovascular interventions on subsequent open bypass.

OBJECTIVE: An endovascular-first approach has been widely adopted as an alternative to surgical bypass in patients who need lower extremity revascularization for femoropopliteal disease. This study evaluated anatomic changes in the extent of bypass and outcomes of open bypass (OBP) surgery after failed endovascular treatment (EVT). METHODS: We reviewed consecutive patients treated by endovascular femoropopliteal revascularization from 2002 to 2012. Patients requiring OBP after failed EVT were analyzed. Blinded investigators reviewed preoperative and postintervention angiographies. The location of the intended distal anastomosis before the endovascular intervention was compared with the open procedure after failed EVT, and results were analyzed for amputation and patency rates. RESULTS: There were 566 patients (322 men [57%]) who underwent 836 endovascular femoropopliteal revascularizations in 665 limbs. Patients were a mean age of 72 ± 11 years. Mean follow-up was 20 months. Indication for revascularization was critical limb ischemia in 33% of patients before the index endovascular procedure. Interventions were performed for de novo lesions in 604 procedures (72%) or restenosis in 232 (28%). TransAtlantic Inter-Society Consensus for the Management of Peripheral Arterial Disease A and B lesions were treated in 547 patients (65%). Balloon angioplasty was used in 822 interventions (98%), with primary or secondary stenting using self-expandable stents performed in 367 (44%). Thirty OBPs were required in 566 patients (5.3%) at an average of 15 months after the index EVT. OBP consisted of 6 above-knee, 14 below-knee, and 10 tibial bypasses. Vein and prosthetic conduits were used equally. Location of the distal anastomosis changed to a more distal target in 13 (5 below-knee and 8 tibial) of 30 patients (43%). Median follow-up was 36 months (range, 0.5-104 months), with a primary patency of 66% at 1 year and 46% at 3 years. Of the 30 bypasses, seven patients required reintervention with percutaneous angioplasty (n = 4) and patch angioplasty (n = 3). Five patients required redo bypass after failed endovascular salvage (lysis or angioplasty, or both), and redo bypass was not attempted in two. Eight patients (27%) progressed to major amputation, for an amputation-free survival of 79% at 1 year and 67% at 3 years. CONCLUSIONS: OBP after failed EVT was needed in a minority of patients. A change in the bypass target to a more distal site was identified in nearly half of patients. Although an endovascular-first approach to treating claudication and critical limb ischemia is safe and resulted in few progressing to OBP, poor outcomes of open interventions after EVT can be expected if EVT fails.