Venous Autografts Research Articles

A rare clinical case of diagnosis and treatment of metastases of Merkel carcinoma in the right inguinal lymph nodes without an identified primary focus

Introduction. Merkel’s carcinoma is a neuroendocrine malignant epithelial skin tumor, rapidly progressive, prone to local recurrence and metastasis to regional lymph nodes and internal organs. The etiology and pathogenesis of Merkel’s carcinoma are still an insufficiently studied issue. Because of its rare occurrence, only single observations of Merkel’s carcinoma metastasis without an identified primary focus, most often with regional lymph node involvement, have been described in the world literature.Clinical case. This article presents a clinical case of metastatic lesion of inguinal lymph nodes with microinvasion into femoral artery in Merkel’s carcinoma without identified primary focus. After a comprehensive examination and onco-consilium the patient underwent surgical treatment in the scope of cytoreductive excision of the inguinal lymph node conglomerate on the right side and artery prosthesis with an autovenous graft. According to the routine postoperative pathomorphologic and immunohistochemical studies, the diagnosis of Merkel’s carcinoma metastasis was finally confirmed.Conclusion. Identification and description of such clinical cases are practically significant and can serve for formation of certain algorithms for treatment of Merkel’s carcinoma both with local manifestations and in progressive forms. Patients with Merkel’s carcinoma should be discussed in oncological consiliums, as treatment may include surgical stage, including biopsy of sentinel lymph nodes, adjuvant radiotherapy, chemotherapy and immunotherapy in case of tumor dissemination.

Fifteen-year results of bilateral and unilateral internal mammary artery grafting

To evaluate the clinical effectiveness of bilateral internal mammary artery grafting over long-term (15 years) postoperative period. There were 276 patients divided into two groups: 135 patients (group A) underwent bilateral internal mammary artery grafting and 141 patients (group B) underwent unilateral internal mammary artery grafting together with venous bypass grafts. On-pump surgeries and cardioplegia, parallel CPB and on-pump procedures were performed in equal proportions. Mean age of patients was 57.3±7.6 years. Diabetes mellitus was detected in 21 (15.5%) and 24 (19.1%) patients, respectively (p>0.05). Mean LV ejection fraction was 55.4±9.9%, revascularization index - 3.1±0.8 and 3.0±0.7, respectively. In the 1st group, 43 patients underwent bilateral internal mammary artery grafting alone. Autovenous grafts were additionally used in other 84 patients. Ten-year survival exceeded 90% in both groups. Freedom from adverse cardiac events after 15 years was significantly higher in group A (77.3% vs. 59.3%, p=0.018). In group A, 16 patients died throughout this period due to cancer (50%), myocardial infarction (12.5%), stroke (18.8%) and complications of diabetes mellitus (6.3%). In group B, 22 patients died mainly from cardiac causes (myocardial infarction - 40.9%, cancer - 27.3%). Bilateral internal mammary artery grafting has obvious advantages over traditional coronary artery bypass grafting. If we take into account higher proportion of cardiac causes in structure of mortality in group B, we can talk about positive impact of bilateral internal mammary artery grafting not only on the quality of life, but also on life expectancy in long-term postoperative period.

Comparison of Arterial and Venous Interposition Grafting for Arterial Defects in a Rat Model.

Interposition microvascular grafting may be required to bridge arterial defects during digital replantation or revascularization and has traditionally been performed utilizing a venous autograft. Arterial interposition grafting has been shown to be superior in maintaining patency in large vessel surgery; there are case reports of its use in microsurgery. Six fellowship-trained hand and microsurgeons performed arterial and venous interposition grafts on the femoral arteries of 40 Wistar rats. After sectioning one femoral artery a segment of the contralateral femoral artery or vein was obtained. The time was recorded per graft and patency tested 10 minutes following grafting by an independent assessor. Each surgeon also completed a questionnaire detailing regular microsurgical volume, technical ease, and conceptual preference for either graft. Time for arterial interposition (median time 51.7 minutes) was longer than venous grafting (median time 45.9 minutes, p = 0.075). Arterial grafts were more likely to be patent or questionably patent (odds ratio [OR] = 6.77, p = 0.031). All surgeons found arterial interposition grafting technically easier and preferred it conceptually. Improvements were noted in patency rates (OR = 11.29, p = 0.018) and avoidance of anastomotic leak (OR = 0.19, p = 0.029) when surgeons performed moderate levels or greater of microsurgery within their regular practice. Greater immediate patency was noted with arterial interposition grafting in a rodent model when compared to venous grafting, although procedural time was greater. All surgeons found arterial grafting technically easier. Arterial microvascular grafting may be useful in the setting of digital replantation or revascularization with an arterial defect.

Predicting the Development of Thrombosis of the Femoral-Popliteal Bypass in the Long-Term Follow-Up Period

Aim of study. The development of a program for predicting thrombosis with subsequent amputation of a limb in the long-term period after femoral-popliteal bypass (FPB).Material and methods. This is a retrospective open comparative study performed from January 10, 2016 to December 25, 2019 at Research Institute – Professor S.V. Ochapovsky Regional Clinical Hospital No. 1 of the Ministry of Health of the Krasnodar Territory, Krasnodar, which included 473 patients who underwent FPB. Depending on the type of bypass, five groups were formed: Group 1 (n=266), reversed vein (great saphenous vein (GSV); Group 2 (n=59), autovenous vein (GSV), prepared in situ; Group 3 (n=66), autovenous vein (GSV), prepared ex situ; Group 4 (n=9) synthetic graft (Jotec, Germany); Group 5 (n=73), veins of the upper limb (forearm and shoulder). In all cases of observation, multislice computed tomography with angiography revealed an extensive (25 cm or more) atherosclerotic occlusive lesion of the superficial femoral artery, corresponding to type D according to the transatlantic consensus (TASC II). The long-term followup period was 16.6±10.3 months.Results. During the hospital postoperative period, all complications developed in groups 1, 2, 3 and 5. However, no significant intergroup statistical differences were found. In the long-term follow-up period, according to the mortality rate (group 1: 4.6%; group 2: 1.7%; group 3: 4.6%; group 4: 0%; group 5: 2.8%; p=0.78), myocardial infarction (group 1: 1.9%; group 2: 0%; group 3: 1.5%; group 4: 0%; group 5: 0%; p=0.62), ischemic stroke (group 1: 0.8%; group 2: 1.7%; group 3: 1.5%; group 4: 0%; group 5: 0%; p=0.8) and bybass thrombosis (group 1: 14.5%; group 2: 19.3%; group 3: 18.5%; group 4: 44.4%; group 5: 19.7%; p=0.16), no significant intergroup differences were identified. However, the largest number of limb amputations (group 1: 4.2%; group 2: 5.3%; group 3: 9.2%; group 4: 22.2%; group 5: 1.4%; p=0.03) and the maximum composite endpoint (sum of all complications) (group 1: 26.0%; group 2: 28.1%; group 3: 35.4%; group 4: 66.7%; group 5: 23 .9%; p=0.05) were observed after the use of a synthetic graft. Using “random forest” analysis, a model and computer program was created that allows, the risk (low, medium, high) of developing bypass thrombosis to be assessed interactively, based on clinical, anamnestic, demographic and perioperative data, with subsequent amputation after FPB in the long-term follow-up period.Conclusions. Revascularization strategy for patients with extended atherosclerotic lesions of the femoropopliteal segment should be determined individually and only by a multidisciplinary council. The conduit of choice for femoral-popliteal bypass surgery is an autovenous graft. Synthetic prostheses can only be used in the absence of the latter. To identify a group of patients with a high risk of thrombosis of the femoral-popliteal bypass and limb amputation in the long-term follow-up period, the created risk stratification program for the development of these complications can be used. Precision supervision of these patients in the postoperative period will make it possible to prevent these adverse events in time.

Femoro-popliteal autogenous venous bypass in surgical treatment of soft tissue sarcomas of the lower limbs: clinical case

Femoro-popliteal autogenous venous bypass in surgical treatment of soft tissue sarcomas of the lower limbs: clinical case

The Utility of the Interosseous Arterial System for Microvascular Interposition Grafting.

Interposition microvascular grafting may be required during digital replantation or revascularisation. Although traditionally performed using venous autograft, the use of arterial segments for microvascular grafting confers a number of benefits. Here, we discuss the harvesting of such a graft from the interosseous arterial system and its use in the clinical setting. Level of Evidence: Level V (Therapeutic).

Predictors of Long-Term Complications of Femoropopliteal Bypass with Autovenous Graft

INTRODUCTION: Atherosclerotic lesion of lower limb arteries often occurs with the development of chronic and later with critical ischemia of the lower limbs. Revascularization in these conditions has always been at the center of attention of vascular surgeons worldwide.
 AIM: To analyze long-term complications after femoropopliteal bypass (FPB) with the autovenous graft.
 MATERIALS AND METHODS: This retrospective open study was conducted in Scientific the Research Institute Regional Clinical Hospital No. 1 named after Professor S. V. Ochapovsky (Krasnodar) in the period from January 10, 2016, to December 25, 2019, and included 464 patients who underwent FPB with venous autograft. The following autovenous conduits were used: n = 266, reverse vein (great saphenous vein (GSV)); n = 59, autovein (GSV) prepared in situ; n = 66, autovein (GSV) prepared ex situ; and n = 73, veins of an upper limb. The long-term follow-up period was 16.6 10.3 months.
 RESULTS: During the postoperative hospital period, single cases of lethal outcome and myocardial infarction were noted. No ischemic strokes were recorded. Shunt thrombosis developed in 4.5% of the patients, and 2.1% required limb amputation. Postoperative wound revision caused by bleeding was performed in 1.7% of the cases. In the remote follow-up period, adverse cardiovascular events were noted in every fifth patient (21.8%). Shunt thrombosis was diagnosed in 17.4% of cases, and limb amputation was performed in 5.1% of the cases. To identify the factors for poor prognosis, the whole sample was divided to two groups: group 1 (n = 366) included those without long-term complications and group 2 (n = 99) comprised patients with long-term complications. Using the odds ratio (OR), the following predictors of adverse cardiovascular events were identified: degree I obesity (р 0.0001; OR = 3.24; 95% confidence interval (CI) = 1.935.43), degree II obesity (р = 0.0005; ОR = 4.84; 95% CI = 1.7113.67), and stage IIB chronic lower limb ischemia (CLLI) (р = 0.0006; ОR = 2.24; 95% CI = 1.423.52). Protective factors were postinfarction cardiosclerosis (р = 0.04; ОR = 0.51; 95% CI = 0.270.95), excessive body mass (р = 0.01; ОR = 0.56; 95% CI = 0.350.88), and stage IV CLLI (р = 0.01; ОR = 0.53; 95% CI = 0.320.86).
 CONCLUSIONS: FPB with venous autograft is characterized by a low frequency of complications in the hospital and long-term follow-up periods, making this technique a method of choice for the open surgical treatment of patients with extended atherosclerotic lesion of the superficial femoral artery. Predictors of adverse cardiovascular events in the long-term period are degree I obesity, degree II obesity, and stage IIB CLLI. Protective factors against the development of long-term surgical complications are postinfarction cardiosclerosis, overweight, and stage IV CLLI. The presented results should be considered when constructing stratification risk scales for adverse cardiovascular events in patients who underwent FPB. Precision management of patients with identified predictors of complications will allow the reduction of the risks for the development of these conditions and increase long-term survival free from shunt thrombosis and limb amputation.

Results of CABG Using Microsurgical Technique and Endarterectomy for Diffuse Lesions of the Coronary Arteries

Background. The number of patients (pts) with diffuse lesions among coronary artery bypass grafting (CABG) candidates has increased; they are expected to have worse results. Complex reconstructions, such as coronary endarterectomy (CEAE) and prolonged anastomoses with arteries less than 1.5mm in diameter, are being used more often. There is no sufficient evidence data and accepted guidelines for surgical treatment of this most complicated category of pts. Aim to evaluate the effectiveness of CABG with and without endarterectomy in pts with diffuse lesion and compare it with standard CABG in pts with local lesion. Materials and methods. In 20102017 CABG were performed in 2.927 pts. 1276 had diffuse coronary artery disease and in 154 cases the surgeon was forced to perform CEAE. After excluding 38 pts with comorbidities, the study group was formed (group 1, n = 116). We selected 2 equally large control groups with propensity score matching: from pts with diffuse lesion operated without CEAE (group 2, n = 116) and pts with local lesion operated as standard (group 3, n = 116). Cardiopulmonary bypass and microsurgical techniques were used. Hospital and long-term (up to 8 years; median follow-up of 60 (42; 74) months results were compared. The endpoints were all-cause and cardiac mortality, myocardial infarction (MI), angina recurrence and repeated revascularization. Results. In group 1 the frequency of perioperative MI was significantly higher compared to groups 2 and 3 (6.9% vs 0.7 and 0.7% resp, p 0.05) Hospital mortality was comparable in groups (p = 0.444). In the long-term period, the angina recurrence frequency was insignificantly lower in both control groups compared with the study group (p = 0.418). Autovenous grafts had significantly more dysfunctions compared with the internal thoracic artery grafts in symptomatic pts (57.5 versus 12.1%, p 0.05; odds ratio OR = 9.82; 95% CI: 3.2429.79). Also the severity of the target coronary artery lesion 4 points scaled by the diffuse lesion index were more frequent cause of graft dysfunction in this group (60.9 versus 41.6%; p 0.05; OR = 2.13; 95% CI: 1.134.24). Conclusion. Coronary endarterectomy is related to the high risk of perioperative myocardial infraction, while do not significantly increase the hospital mortality and adverse events in the long-term period. It should be considered to use coronary endarterectomy when there is no other option for surgery. The using of other adjunctive techniques demonstrate high efficiency in patients with diffuse lesions of the coronary arteries, comparable to surgery in patients with local lesion.

Comparative retrospective analysis of the results of open femoral-popliteal bypass grafting and endovascular stenting with an interwoven biomimetic stent in patients with prolonged occlusions of the arteries in the femoropopliteal segment

Introduction. Autovenous graft is considered the gold standard for prolonged occlusive lesions of the arteries in the femoralpopliteal segment. However, the vein is not always anatomically suitable for bypass grafting; it may have been previously used in previous operations, for example, in coronary artery bypass grafting. Open surgery is always more traumatic than endovascular surgery. Conventional nitinol stents show unsatisfactory results in the femoral-popliteal position due to the high percentage of reocclusions associated with their breakage during physiological movements in the leg joints. The modified method of making interwoven nitinol stents allows improving their biomimetic properties and reducing the percentage of breakages and, accordingly, reocclusions.Material and Methods. There was a retrospective analysis of 437 patients with prolonged atherosclerotic occlusive lesion in the femoropopliteal segment (> 20 cm). There were two groups: a group of bypass surgery and a group of endovascular intervention. The pseudo-randomization method of propensity score matching was used to align the groups according to various criteria.Results. Primary and secondary patency rates for one- and two-year follow up were comparable between the two groups. A subgroup analysis of above-knee intervention showed that a two-year secondary patency rate was significantly higher in the endovascular intervention group than in the bypass group (90.9% vs. 77.5%, p = 0.048). The subgroup analysis of interventions below the knee joint showed that the patency rates at two years of primary and primary-assisted patency were significantly higher in the endovascular intervention group than in the bypass group with an artificial expanded polytetrafluoroethylene (ePTFE) graft (66.7% versus 42.4%, p = 0.046 and 76.7% versus 45.5%, p = 0.011, respectively). The autovenous graft showed better results for primary patency compared with the endovascular intervention group, but the difference was statistically insignificant (77.2% versus 66.7%, respectively, p = 0.3).Conclusion. The analysis of obtained results suggests that the primary endovascular strategy may be recommended for all prolonged occlusive lesions of the femoropopliteal segment above the knee joint gap. For lesions below the knee joint, the autovenous bypass grafting remains the operation of choice, but in the absence of a suitable autovenous graft, the primary endovascular strategy may also be recommended. Additional large multicenter randomized trials are required to refine these recommendations.

Vascular Remodeling of Clinically Used Patches and Decellularized Pericardial Matrices Recellularized with Autologous or Allogeneic Cells in a Porcine Carotid Artery Model.

Background: Cardiovascular surgery is confronted by a lack of suitable materials for patch repair. Acellular animal tissues serve as an abundant source of promising biomaterials. The aim of our study was to explore the bio-integration of decellularized or recellularized pericardial matrices in vivo. Methods: Porcine (allograft) and ovine (heterograft, xenograft) pericardia were decellularized using 1% sodium dodecyl sulfate ((1) Allo-decel and (2) Xeno-decel). We used two cell types for pressure-stimulated recellularization in a bioreactor: autologous adipose tissue-derived stromal cells (ASCs) isolated from subcutaneous fat of pigs ((3) Allo-ASC and (4) Xeno-ASC) and allogeneic Wharton’s jelly mesenchymal stem cells (WJCs) ((5) Allo-WJC and (6) Xeno-WJC). These six experimental patches were implanted in porcine carotid arteries for one month. For comparison, we also implanted six types of control patches, namely, arterial or venous autografts, expanded polytetrafluoroethylene (ePTFE Propaten® Gore®), polyethylene terephthalate (PET Vascutek®), chemically stabilized bovine pericardium (XenoSure®), and detoxified porcine pericardium (BioIntegral® NoReact®). The grafts were evaluated through the use of flowmetry, angiography, and histological examination. Results: All grafts were well-integrated and patent with no signs of thrombosis, stenosis, or aneurysm. A histological analysis revealed that the arterial autograft resembled a native artery. All other control and experimental patches developed neo-adventitial inflammation (NAI) and neo-intimal hyperplasia (NIH), and the endothelial lining was present. NAI and NIH were most prominent on XenoSure® and Xeno-decel and least prominent on NoReact®. In xenografts, the degree of NIH developed in the following order: Xeno-decel > Xeno-ASC > Xeno-WJC. NAI and patch resorption increased in Allo-ASC and Xeno-ASC and decreased in Allo-WJC and Xeno-WJC. Conclusions: In our setting, pre-implant seeding with ASC or WJC had a modest impact on vascular patch remodeling. However, ASC increased the neo-adventitial inflammatory reaction and patch resorption, suggesting accelerated remodeling. WJC mitigated this response, as well as neo-intimal hyperplasia on xenografts, suggesting immunomodulatory properties.

SURGICAL TREATMENT IMMEDIATE RESULTS OF LOWER LIMBS CHRONIC CRITICAL ISCHEMIA IN IMMULTANEOUS DIRECT AND INDIRECT REVASCULARIZATION

The aim: To assess the immediate results of autovenous femoral-tibial shunting in combination with rotary osteotrepanation of the tibia by studying changes in the transcutaneous ptO2 tension in the tibia and foot tissues depending on the revascularization of the tibial arteries. Materials and methods: We analyzed the treatment of 69 patients with obliterating atherosclerosis of the vessels of the lower extremities. According to the degree of ischemia of the lower extremities, the patients were distributed as follows: III A degree of ischemia - 20 (29%), III B - 28 (40.6%), IV - 21 (30.4%) patients. All patients had atherosclerotic lesions of the popliteal-tibial segment of the great arteries with preserved central blood flow in the aorto-iliac segment. Results: Occlusion of the anterior tibial artery was recorded significantly more often than the peroneal artery (72% and 42%, respectively, p = 0.05), but with the same frequency compared to the posterior tibial artery (68%, p = 0.61). The lesion of two or three arteries of the lower leg was recorded more often than occlusion of one (n = 51; 73.9% and n = 18; 26.1%). Occlusive-stenotic lesion of the popliteal artery was observed in 54 (78.2%) patients. The highest incidence of lesions of the tibial arteries was observed in the basin of the anterior tibial artery in 28 (40.6%) patients. Combined lesions of the anterior tibial artery and posterior tibial artery were diagnosed in 19 (27.5%) patients. Limited lesions of the posterior tibial artery were found in 15 (21.7%) patients. The combination of lesions of the posterior tibial artery and peroneal artery was diagnosed in 7 (10.2%) patients. Conclusions: 1. The patency of the femoral-tibial autovenous shunt during the year was 71%. High limb amputation was performed in 29% of patients. 2. According to CT data, the localization of trophic changes on the foot during critical ischemia of the lower extremities corresponds to the affected segment of the arterial angiosome, which supplies the corresponding area with blood. 3. After femoral-tibial autovenous bypass grafting, the highest levels of transcutaneous oxygen tension were observed in the basin of the posterior tibial artery and peroneal artery, and the lowest indicators of transcutaneous oxygen tension were observed in the basin of the anterior tibial artery. 4. During femoral-tibial autovenous shunting operations in combination with rotary osteotrepanation, the transcutaneous oxygen tension indices increased threefold in the angiosomal basin of the posterior tibial artery and peroneal artery, and twofold in the angiosomes of the dorsum of the foot and sole.

Early results of multiple coronary artery bypass grafting on arteries less than 1.5 mm in diameter

Abstract The widespread using of coronary artery (CA) stenting has led to the fact that nowadays coronary artery bypass grafting (CABG) is the method of choice for patients with multiple occlusions and diffuse lesions, who can be refused in surgery due to “small”, not specified in the guidelines, CA (diameter less than 1.5 mm). The use of microsurgical technique makes it possible to reconstruct small-caliber vessels, however, no detailed comparative data has been published yet. Aim To analyze the efficacy of CABG using microsurgical techniques for multiple CA bypass with arteries less than 1.5 mm and compare the results with coronary surgery of larger vessels in the early postoperative period. Methods We studied the early results of CABG in two groups of patients. The study group was represented by 100 patients with multiple coronary artery lesions with d<1.5 mm, who underwent control MSCT-shuntography in the postoperative period. We formed a control group of 100 patients who underwent CABG with a target artery d>1.5 mm. In all cases cardiopulmonary bypass and microsurgical technique were used. Results All patients underwent complete revascularization of CA, the average number of distal anastomoses was 4,3±0,5 in the study group versus 3.6±0,3 in the comparison group, p<0,001. Intraoperatively in the study group significantly more often performed complex anastomoses to arteries <1,5mm (47 patients vs 18, p<0,001), onlay-flap anastomoses (23 vs 1, p<0,001), single and multiple endarterectomies (19 vs 1, p<0,001). The need for long-term inotropic support (15 cases vs 13, p=0,684), as well as prolonged artificial lung ventilation (2 vs 3, p=0,651), in hospital stage was similar in both groups. Patients from the study group more often underwent reexploration for bleeding in the early postoperative period, which was explained by a large number of complex reconstructions and prolonged on pump time, nevertheless, the difference did not reach statistical significance (4 vs 2, p=0,407). Perioperative myocardial infarction (MI) were registered in 3 (3%) and 1 (1%) cases in the study and control groups, respectively, p=0,621. All patients in the study group underwent MSCT-shuntography in the early postoperative period, according to which 8 patients (8%) had occlusion of the autovenous coronary grafts to the CA<1.5mm and 4 patients (4%) - occlusion of the bypasses to CA>1.5 mm. Conclusion CABG in patients with coronary arteries less than 1.5 mm in diameter requires complex reconstructive techniques significantly more often. Nevertheless, in the early postoperative period, it is possible to achieve comparable results in the patient groups with and without CA<1,5mm in the anastomotic sites. Funding Acknowledgement Type of funding sources: None.

Remote results of infrainguinal bypass graft procedures for critical lower limb ischaemia

The study was aimed at assessing the remote results of infrainguinal reconstructions in patients with critical lower limb ischaemia depending upon the bypass graft material used. Analysed herein are the results of 237 infrainguinal bypass procedures performed over a 9-year period from January 1st, 2010 to December 31st, 2018. The patients were divided into three groups depending on the level of the distal anastomosis. Each group was then subdivided into subgroups based on the bypass graft material. Group One comprised 40 patients having endured femoral-proximal-popliteal bypass grafting. Group Two was composed of 77 patients after femoral-distal-popliteal bypass graft operations. Group Three included 120 patients after femorotibial bypass graft procedures. The comparative analysis was carried out in the first group between autovenous and synthetic grafts, in the second group - between autovenous, synthetic grafts and xenografts, and in the third group - between autovenous, composite grafts and xenografts. The primary patency rates at 1, 3, and 5 years in the first group amounted to 92, 88, and 73%, in the second group to 68, 60, 45% and in the third group - to 58, 49, and 43%, respectively. The 1-, 3-, and 5-year limb salvage rates in the first group were 100, 100, and 87%, in the second group - 90, 85, 73%; and in the third group - 90, 80, and 79%, respectively. Statistically significant differences were observed only when comparing the femoral-proximal and tibial grafts (p=0.039). Patients' survival at 1, 3, and 5 years in all groups turned out to be approximately similar, amounting in the first group to 92, 84, and 61%, in the second group to 96, 91, 71%, and in the third group to 88, 77, and 69%, respectively (p=0.87). In the first group, there were no significant differences between autovenous and synthetic grafts for any of the parameters studied. In the second group, the synthetic grafts (20%) were significantly inferior by the 5-year patency to autovenous grafts (65%) and xenografts (56%), as well as by the limb salvage rate to autovenous grafts (47 versus 84%). In the third group, the 5-year patency was the worst for the subgroup of composite grafts (15%), with the patency of xenografts being slightly inferior to that of autovenous grafts (33 vs. 55%). In patients presenting with critical ischaemia and requiring infrainguinal bypass grafting, as an alternative to an autovein if unavailable may serve synthetic prostheses when shunting to the proximal portion of the popliteal artery, or xenografts when shunting to the distal portion of the popliteal artery or tibial arteries. Despite worse patency, with their help it is possible to achieve regression of critical ischaemia and an acceptable limb salvage rate, which is comparable to the results of autovenous grafts.

Tendoplasty and its effectiveness in the rehabilitation of hearing loss in patients with otosclerosis

The article briefly presents the physiology of the stapes muscle tendon (SMT), and features in its defeat. Its length was studied using high-resolution multispiral computed tomography of the temporal bones. We also studied the possibility of its restoration using the author's method of tendoplasty using metallized stapes prostheses. Tendoplasty with stapedoplasty was performed in 74 patients with otosclerosis (OS), and 48 patients had stapedoplasty without tendoplasty. As a result of research, the average length of the SMT was 2.38±0.02 mm, which explains the need to use a 3 mm long venous autograft for tendoplasty. The author's method of tendoplasty for stapedoplasty allows restoring the acoustic reflex in 54.1% of OS patients using artificial stapes prostheses. The preservation of the vascular bed in the thickness of the restored tendon can improve the trophy of the long incus process and reduce the risk of its dystrophic changes in the postoperative period. In addition, this fact confirms the importance of the stapes muscle in the acoustic reflex.

Complications Following Pre-Operative Radiotherapy and Vascular Reconstruction to the Groin in Sarcoma Patients: A Series of Cases

Background: The mainstay of therapy in most soft tissue sarcomas is a combination of surgery and radiotherapy. Although aimed directly at the tumor, radiotherapy may also cause damage to surrounding tissue, particularly at therapeutic levels. In most cases, irritated tissue will heal well, although some longlasting effects may remain. In patients presenting with large sarcomas near the groin, pre-operative radiotherapy followed by radical excision and vascular reconstruction is a common practice. However, neither synthetic vascular grafts nor venous autografts tend to react well to radiotherapy. Case Presentation: In this case series, we report 3 patients who underwent pre-operative radiotherapy prior to vascular reconstructive surgery. In all 3 cases, many post-operative complications necessitated multiple further operations. Two of the 3 eventually required an above and below knee amputation, and the third developed sepsis and pulmonary metastasis. We discuss the role of pre-operative radiotherapy and vascular reconstruction to the groin in sarcoma patients, and query whether this combination could be reconsidered given the potential consequences. We also discuss the efficacy of a lower therapeutic radiotherapy dose and the effect this may have on surgical outcomes. Conclusion: The combination of pre-operative radiotherapy and vascular reconstruction to the groin in sarcoma patients may carry significant morbidity, thereby putting the limb and/or life at risk. The need for pre-operative radiotherapy in groin sarcoma patients requiring vascular reconstruction should therefore be considered very carefully by an expert multidisciplinary team. Post-operative radiotherapy may be a suitable alternative.

Surgical policy in treatment of patients with infected aortofemoral bifurcation allografts

Described in the article are the results of treating a total of 44 patients who endured repeat operations for infection of aortofemoral bifurcation allografts over the period between 2001 and 2018. These patients had previously undergone reconstructive operations using various synthetic grafts for lower limb ischaemia on the background of lower-limb artery atherosclerosis and infrarenal aortic aneurysms. Infection of synthetic vascular allografts in these patients was observed both in the immediate and remote postoperative periods. The dominating infection in 70% of patients was methicillin-resistant Staphylococcus aureus. The main objective risk factors for infection of bifurcation grafts were found to be as follows: stage III-IV chronic lower limb ischaemia (according to the Fontaine-Pokrovsky classification), diabetes mellitus, and prior operations on lower-limb arteries. Two of the 44 patients were operated on for reinfection after repeat aortofemoral bypass grafting. 30% of patients underwent repeat surgery with symptoms of sepsis. After meticulous additional examination and preoperative preparation the patients were subjected to secondary simultaneous operation, i.e., removal of the synthetic aortofemoral bifurcation prosthesis and aortofemoral bifurcation autovenous repeat reconstruction (repeat bypass grafting) in situ. Aortofemoral bifurcation grafts were formed using superficial femoral veins from both legs. Four patients died in the immediate postoperative period. Other short-term complications included arrosive bleeding with or without sepsis, amputation of one leg due to graft limb thrombosis, and development of peritonitis resulting from perforation of the jejunum. In the remote period, patency of autovenous grafts was confirmed in 37 patients. Of long-term complications, mention should be made of the following: formation of aneurysms of distal anastomoses and thrombosis of one of the limbs of the autovenous graft. The patients were successfully operated on now using synthetic grafts in infection-free conditions. Hence, a method of surgical decision-making in patients with infected aortofemoral bifurcation grafts is the use of the technique of complete removal of the infected synthetic graft with simultaneous in situ replacement using autovenous grafts from superficial femoral veins, active pre- and postoperative antibiotic therapy. Such policy made it possible to decrease the mortality rate to 9%, with a limb-salvage rate of 97.5% and long-term graft patency rate amounting to 92.5%.

Comparative Evaluation The Role of Venous and Peritoneal Autograft as Bioscaffold for Repairing Achilles Tendon Defect in Dogs

The study was conducted on eighteen healthy dogs, which were allocated into three equal groups (six dogs each). In the first treatment, the hind limbs were prepared at the calcaneus region where Achilles’ tendon was sharply incised, sutured with Kessler method, and immobilized with gypsona. The second treatment included the using of a peritoneum graft, while the third treatment utilized the venous autograft. Following surgery, all animals were inspected clinically, grossly and histopathologically for two months. Results of the first treatment exhibited adhesion and inflammatory reaction after one and two months of surgery. Histopathological examination revealed the organization of collagen fibers and mild inflammatory reaction after two months of surgery. The second treatment exhibited complete healing and the animal showed normal activities without any impairment on leg function. Grossly, a mild degree of adhesion was determined after two months of surgery. Histopathological examination exhibited complete granulation tissue formation with the slightest degree of fibroblast formation at 60 days. In the third treatment, there was an inflammatory reaction with moderate adhesion at one month of surgery. However, after 60 days post operation, the tendon restored the normal anatomical feature. In conclusion, unlike other treatments, results obtained from the using of peritoneal graft for reconstruction tendon defect was with the most convincing and efficient outcomes. The findings reported here shed a new light on treating of the defective tendon.

Fabricating mechanically improved silk-based vascular grafts by solution control of the gel-spinning process

There is a large unmet need for off-the-shelf biomaterial options to supplant venous autografts in bypass and reconstructive surgical procedures. Existing graft alternatives formed from non-degradable synthetic polymers are not capable of maintaining long-term patency and are thus not indicated for <6 mm inner diameter bypass procedures. To fill this void, degradable silk-based biomaterials have been proposed that can maintain their mechanical properties (i.e. compliance) while facilitating slow but progressive biomaterial remodeling and host integration mediated by cellular colonization. The goal of the present study was to enhance the porosity of gel-spun silk tubes, to facilitate faster degradation rates and improve cellularity, and thus improve host integration over time in vivo, while maintaining requisite mechanical functions. Silk solutions with a range of molecular weight distributions and, in turn, viscosities were used to generate tubes of varying porosities. A decrease in solution concentration correlated with an increase in mean pore size and overall porosity through a density-dependent mechanism. Tubes were mechanically analyzed, and these properties were the basis of an analytical model used to correlate tube formulations to structural compliance, which were shown to be similar to the saphenous vein. Tubes were also tested for suture retention to ensure surgical utility despite increased porosity. Tubes were implanted in the abdominal aorta of Sprague-Dawley rats via an end-to-end anastomosis model. Tubes with higher porosities showed early improvements in cell colonization that progressively increased over time; conversely, the dense architecture of less porous grafts (20MB) inhibited cell ingrowth and resulted in minimal biomaterial degradation at the 6-month time point. None of the highly porous tubes (5 MB and 10MB) remained patent at 6 months, likely due remodeling inducing bulk mechanical failure or a compromised blood-material interface.

Pseudoaneurysms of the Lower Extremity Vessels as a Complication of Hereditary Exostose Chondrodysplasia in Adolescents (Two Case Reports)

The article describes two clinical cases of vascular complications related to hereditary exostose chondrodysplasia of the lower limbs in children. Despite early diagnostics the newgrowth was not timely removed. The anatomical localization of the exostoses in the vicinity of the main arterial trunks resulted in formation of pseudo-aneurysms due to a prolonged exposure of the vascular wall to the actively growing bone formations. After diagnostic imaging (ultrasonography and Doppler sonography, CT angiography, MR angiography of the vessels in the lower extremities) the authors performed a simultaneous resection of the femoral artery aneurysm with autovenous grafting and total resection of exostoses in both cases. Late follow up of both patients demonstrated vascular permeability at the graft site and no symptoms of stenosis were observed.

Causes of unsatisfactory surgery results of gunshot extremity arterial injuries

The aim — to identify the characteristics of injured persons’ group with limb preservation failure, as well as the factors that led to the limb loss, despite the revascularization attempts, that allows the prognosis and outcome improvement in the injure treatment.Materials and methods. The data on 100 patients who were injured during an anti‑terrorist operation (Joint Forces Operation) in eastern Ukraine between 2014 and May 2019, underwent revascularization for main artery injuries on the extremities, were analysed. Among them were 28 patients with upper limb injuries and 72 patients with lower limb injuries. The amputation was performed in 5 (17.9 %) cases in the group of patients with upper limb injuries, in 12 (17.7 %) patients with lower extremities injuries in the next days or weeks. A cohort of patients with successful revascularization and one with limb loss were analysed. The analysis took into account such wounds’ features as the injury nature, the major soft tissues loss, the evacuation term, the term before specialized care, the accompanying damage to other anatomical structures in the wound area, the presence of combined trauma, the surgery type and condition severity on the moment of evacuation.Results and discussion. The number of prophylactic fasciotomies was lower in the amputee group compared to the group with preserved limbs (35 and 48 %, respectively). The total number of autovenous graft operations in both groups was 51. In 14 (27 %) cases, the amputation was further performed. After prostetic graft (n = 24), 3 (13 %) limb amputations were performed.Conclusions. The most significant factors that led to the unsatisfactory result of revascularization were a major soft tissues loss in the in the wound area, delayed evacuation to a specialized hospital, a severe general condition, concomitant damage to other anatomical structures in the wound area. The most unfavourable prognosis for a reconstructive intervention is a combination of the artery, vein, main nerves, and tubular bone damage («lost limb syndrome»). The choice of a synthetic alloprosthetic for revascularization in gunshot wounds does not increase the risk of further amputation.