Objective To evaluate surgical treatment of infected femoral artery pseudoaneurysm. Methods The data on surgical treatment of 45 patients with infected femoral artery pseudoaneurysm admitted from January 2003 to June 2008 were analyzed retrospectively. Fourty-three patients underwent operative treatment including excision of infected femoral artery pseudoaneurysm, exhaustive debridement and bypass graft with vascular prosthesis. Two patients were unavoidable to undergo removing of infected femoral artery pseudoaneurysm and ligating the proximal and distal artery of pseudoaneurysm because of severe infection and large volume. Results The patients were followed up from 3 to 12 months (mean 7.82 months). The limbs of all the patients underwent bypass graft with vascular prosthesis were salvaged successfully, patients of which had secondary wound healing and had not intermittent lameness. One of two patients performed ligation of artery was salvaged successfully but had severe intermittent lameness, another patient underwent high amputation above knee because of ischemic gangrene. Conclusion For infected femoral artery pseudoaneurysm, the operative treatment including excision of infected femoral artery pseudoaneurysm, exhaustive debridement and bypass graft with vascular prosthesis is effective and safe.
Objective To study the effect of preparation conditions for small-diameter polyurethane(PU) vascular graft on microstructure and mechanical properties. Methods The small-diameter microporous PU artificial vascular grafts were prepared by dipping and leaching method. The dimension and microstructure were controlled by changing mold diameter, PU materials, salt sizes, salt to polymer ratio, times of dipping layers etc. The mechanical properties of PU grafts including radical compliance, water permeability, longitudinal strength, burst strength, and suture tearing strength were measured and the effect of the graft dimension and microstructure on their properties were studied. Results The internal diameter of grafts prepared was 2-4 mm depending on mold diameter. The wall thickness was 0.6-1.2 mmafter dipping 4-8 layers. The density was 0.23-0.49 g/cm3. The pore was 42-95 μm in diameter. The porosity was 56%80%. The radical compliance was 1.2%-7.4%·13.3 kPa-1 and higher compliances could be obtained by using moreelastic polyurethane, higher salt to polymer ratio, longer diameter and less wall thickness. The water permeability, mainly depending on salt to polymer ratio,diameter, and wall thickness, was 0.29-12.44 g／(cm2·min). The longitudinal strength was 1.55-4.36 MPa correlating with tensile strength of polyurethane and salt to polymer ratio. The burst strength was 60-300 kPa also depending on tensile strength of polyurethane and salt to polymer ratio. The suture tearing strength was 19.5-96.2 N／cm2 depending on tensile strength of polyurethanebut not on the angle of tearing and graft axial directions. The compliance and water permeability of Chronoflex grafts were higher than those of PCU1500 grafts, but longitudinal strength, burst strength, and suture tearing strength of PCU1500 grafts were better than those of Chronoflex grafts. Conclusion Small-diameter grafts with proper pore sizes, porosity, matching compliance can be obtained by selecting PU materials and optimizing the preparation conditions.
Objective To summarize the current progress in the genetic modification of vascular prostheses and to look forward to the future of genetic modification in vascular prostheses. Methods PubMed onl ine search with the key words of “vascular prostheses, gene” was undertaken to identify articles about the genetic modification of vascular prostheses. Then these articles were reviewed and summarized. Results To improve long-term patency of vascular prostheses, various genes were transfected into seeded cells. The antithrombosis activity of local vessels increased. Conclusion Progresses in tissue engineering and molecular biology make possible endothel ial ization and genetic modification of vascular prostheses. However, because most relevant researches are still basic experiments, further study is needed before cl inical appl ication.
ObjectiveTo investigate whether the recombinant human growth hormone (rhGH) can promote endothelialization, inhibit vascular intimal hyperplasia, and improve long-term patency rate by the treatment of rhGH after vascular prostheses bypass. MethodsBetween August 2007 and January 2009, 94 patients with lower extremity arteriosclerotic occlusive disease were treated. Among them, 32 patients (34 limbs) who met the selection criteria were enrolled in this study. All cases were randomly divided into study group (16 cases, 18 limbs) and control group (16 cases, 16 limbs). There was no significant difference (P>0.05) in gender, age, disease time, location of lesions, the Trans-Atlantic Inter-Society Consensus (TASC) grade, and basic diseases between 2 groups. The patients with superficial femoral artery disease received above-knee femoro-popliteal prostheses bypass. The patients who had combined abdominal-iliac artery disease received concurrent abdominal-femoral and femoro-popliteal prostheses bypass. Subcutaneous injection of 9 U rhGH was given every night for 7 days in study group, and saline was applied in control group. Ultrasonography was taken after 2 weeks and 3 months of operation to observe the patency and measure the wall thickness of vascular prostheses. ResultsAfter operation, 1 patient of control group died of renal failure caused by acute thrombosis. After 2 weeks, ultrasonography showed no obvious intimal hyperplasia in 2 groups; the wall thickness was (0.13±0.02) cm in study group and (0.15±0.03) cm in control group, showing no significant difference (t=-1.720, P=0.108). After 3 months, the wall thickness was (0.17±0.06) cm in study group and was (0.26±0.09) cm in control group, showing significant difference (t=-2.240, P=0.045). All cases were followed up 36-60 months (mean, 56.4 months). The 5-year primary patency rate was 52.5% in study group and 35.7% in control group, showing no significant difference (χ2=1.470, P=0.225). ConclusionThe rhGH can improve endothelialization in vascular prostheses and can inhibit postoperative vascular intimal hyperplasia in clinical application.
Objective To study the feasibility of transplanting human saphanous vein endothelial cells to luminal surface of blood vessel prosthesis and to play a theoretical foundation for the clinical application of autologous endothelial cell transplantation. Methods Human saphanous vein endothelial cells were harvested with 0.1% collagenase and cultivated in vitro for 13.08±1.24 days. The cultures were confirmed as endothelial cells with the fourescent linked anti-Ⅷ antigen antibodies. The content of both 6-keto-PGF1α and Von Willebrand factor (vWF) in the supernatant were detected with ELISA and radioimmunoassay. The multiplied cells were lined in vitro onto the luminal surface of expanded polytetraflouroethylene (ePTFE) grafts precoated with fibrin glue and fibronectin, then cultivated again for 9 days. Results 11.46±2.69×１０６ of available endothelial cells could be regularly obtained, the number of endothelial cells increased 147.93±88.68 times when culture were terminated. All the cells diploid cells with a purity of 99%. The content of both 6-keto-PGF1α and vWF in the media showed no significant difference between the primary and subculture passages. The luminal surface of grafts was covered completely by a spindlelike endothelial monolayer and an even fibrin glue matrix could be seen underneath. Conclusion Endothelial cells derived from human saphanous veins might be feasible to be transplanted onto the luminal surface of ePTFE and present a potential clinical application.
The Dacron grafts seeded with autologous venous fragments were implanted into IVC of 13 canines as seeded group and the control grafts (8 cases), which were only preclotted with fresh blood. The amounts of cAMP and cGMP in serum and within platelet were measured. All of the specimens explanted at exsaguination were observed morphologically. The results shown that the total patency rate were 61.5% in seeded group, but 25.0% in control one and new endothelial lining formed at two weeks after implantation of the seeded grafts. The amounts of cAMP in serum and within platelet were higher in seeded group, but the amounts of cGMP were lower in serum and within platelet. These were in accordance with the results that the endothelialization of the grafts were complete in seeded group but not complete in control one. The results indicate that seeding Dacron with autologous venous fragment makes new endothelium formed at two weeks after implantation, increases the amounts of cAMP in serum and within platelet, but reduces the amounts of cGMP and thus improves graft patency rate.
ObjectiveTo explore the role of arteriovenous axillary loop graft (AVALG) on chest for establishing hemodialysis access in patients with chronic renal failure. MethodsA retrospective analysis was made on the clinical data of 12 patients with chronic renal failure who underwent an AVALG on chest for hemodialysis access between December 2010 and May 2014. There were 2 males and 10 females with an average age of 65.25 years (range, 46-75 years). The main causes were chronic glomerulonephritis in 6 cases, diabetic nephropathy in 4 cases, and both kidney resection because of urinary tract tumors in 2 cases. The disease duration was 2-12 years (mean, 6 years). The 12 patients all underwent 5-14 times (mean, 7 times) failed prior vascular accesses [arteriovenous fistula (AVF）and arteriovenous graft (AVG)] leading to exhaustion of venous access sites on the upper extremities. ResultsThe AVALG on chest were functionally useful for hemodialysis access, 2-3 times per week, and the blood flow was 250-350 mL/minute; the average time for the first dialysis was 48 days (range, 42-93 days). All patients were followed up 12-54 months (mean, 20.92 months). There was no death during perioperative period. The primary patency rates at 6 and 12 months were 91.7% and 83.3% respectively, and the secondary patency rates at 6 and 12 months were both 100%. After operation, infection (1 case), thrombosis (2 cases), bleeding (2 cases), and swollen (1 case) occurred, which were all cured after corresponding treatment. ConclusionAVALG on chest is a supplementary option for chronic renal failure patients with inadequate upper extremity venous access sites after repeat occlusion.