Assessment of the mechanical properties and biocompatibility of a new electrospun polyurethane vascular prosthesis / 南方医科大学学报

<p><b>OBJECTIVE</b>To develop a small-caliber vascular grafts and study its morphologies, mechanical properties and biocompatibility.</p><p><b>METHODS</b>The effects of electrospinning conditions on the microstructure and porosity of the resulting scaffolds were investigated for preparation of a small-caliber (4 mm) polyurethane vascular grafts with optimum microstructures and mechanical properties. The mechanical properties and biocompatibility of the prepared grafts were evaluated.</p><p><b>RESULTS</b>The polyurethane vascular grafts showed a three-dimensional reticular structure consisting of nanofibers, with an average porosity of (51.48∓4.47)% and tensile strength of 5.85 ∓ 0.62 MPa. The grafts provided a better long-term support than e-PTFE graft for endothelial cell growth and endothelialization.</p><p><b>CONCLUSION</b>The polyurethane vascular prosthesis possessed favorable microstructures, excellent mechanical properties and good biocompatibility for potential clinical application.</p>

Stent-grafting for unfavorable abdominal aortic aneurysm: a practical challenge / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The endovascular treatment of abdominal aortic aneurysm (AAA) has improved greatly in the last 15 years. The present study aimed to evaluate the endografting experience for the treatment of unfavorable abdominal aortic aneurysm (uAAA).</p><p><b>METHODS</b>During December 2001 and December 2007, 41 patients with uAAA were treated with endografting using concomitant techniques. Patients were followed up for 1 to 48 months (mean 20.5 months).</p><p><b>RESULTS</b>Technical success rate was 97.6% (40/41) with 1 failure converted to open surgery for an unaccessed iliac stenosis. Nine (22.5%) type I endoleaks (5 proximal and 4 distal) were observed on the completion angiograms and successfully corrected with aortic cuffs and iliac extensions during the procedure. Twenty-two of the planed adjunctive procedures were concomitantly performed just before endograft-implantation. There were 2 (5.0%) type I endoleaks at 30 days; one type I patient was treated by open conversion, another type I patient died from a rupture before treatment in the ward, causing a 2.5% of initial mortality. The two type II endoleaks were observed without aneurismal expansion. No buttock or leg claudication or ischemic colitis occured. During late follow-up, one additional death occurred from stroke. One new type I endoleak was encountered from thrombocytopenia, which caused a 2.6% secondary endoleak that converted to an open surgery in the third month after a failed transabdominal banding of the aortic neck in the second month. All type II endoleaks had disappeared in the third and sixth month. The Endografts did not present signs of material fatigue and no other type of endoleak formed. One patient presented with left limb ischemia, which underwent percutaneous transluminal angioplasty. There was no additional aneurysm rupture or any endograft imgration.</p><p><b>CONCLUSION</b>The endografting with concomitant procedures is a feasible and efficient alternative for managing unfavorable AAAs, achieving low morbidity and mortality rates and has a good clinical outcome.</p>

Early to mid-term results of endovascular repair of aortic dissection: report of 165 cases / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the early and midterm outcomes of endovascular repair of aortic dissection (AD).</p><p><b>METHODS</b>Between January 2001 and December 2006, 165 patients (145 male and 20 female) with AD were treated with endovascular repairing. The mean age of the patients was 52.8 years (range, 30-82 years). Among them, 36 patients had Stanford type A dissection, 121 had type B dissection and 8 had aortic ulcer. Among the dissection patients, 47 were acute AD (the interval between onset and surgery was < or = 7 days), 69 were subacute AD (the interval between onset and surgery was 8-30 days) and 41 were chronic AD (the interval between onset and surgery was > 30 days).</p><p><b>RESULTS</b>The stents were placed technically successfully in 164 patients (99.4%). The rate of endoleak within 30 days after placement of stents was 7.3% (12/165) and neurologic complication rate was 2.5% (4/165). The mortality rate within 30 days was 6.1% (10/165), and the mortality of acute, subacute and chronic AD was 12.8%, 1.4% and 7.3%, respectively. One hundred and forty-five cases were followed up for 6 to 75 months (median, 28.2 months). Complete thrombosis in false lumen was achieved in 62 patients (42.8%), while partial thrombosis was achieved in 83 patients (57.2%). Nine patients died during fellow-up.</p><p><b>CONCLUSION</b>It's indicated that endovascular repair of AD is a microinvasive, safe and effective methods for aortic dissection. However, the long-term efficacy needs to be evaluated further.</p>

Endovascular stent-graft treatment for DeBakey I aortic dissection / 中华外科杂志

<p><b>OBJECTIVE</b>To study endovascular treatment of DeBakey type I aortic dissecting aneurysm.</p><p><b>METHODS</b>Seven patients with DeBakey I aortic dissecting aneurysms were treated. Diagnoses were confirmed by MRA, CT and angiography. The intimal tear entry was in the ascending aorta, 2.5 approximately 6.0 cm from the ostia of the coronary arteries, and 0.5 approximately 4.0 cm from the brachiocephalic trunk opening. Endovascular stent-grafts were deployed via a left common carotid artery (LCCA) approach in 2 cases and right femoral artery (RFA) approach in 5 cases. Prior to treatment, a left subclavicular artery (LSA)-LCCA shunt was established to ensure blood supply to the LCCA during surgery in 2 cases via LCCA approach, and a LSA-LCCA-right common carotid artery (RCCA) synthetic bypass was established to ensure blood supply to the brain in 2 cases in RFA approach.</p><p><b>RESULTS</b>The operative success rate was 100%. In 3 cases, endoleak persisted after the first stent was placed, but this was eliminated by placement of a second stent. All patients survived except one who died of acute massive hemorrhage from the upper gastrointestinal tract one month postoperatively. The false lumen in all 6 cases became thrombosed and no endoleak or new aortic dissecting aneurysms developed.</p><p><b>CONCLUSIONS</b>Endovascular treatment of DeBakey type I aortic dissecting aneurysm is feasible, minimally invasive, and effective. Case selection depends on the distance of the coronary artery ostia from the tear entry.</p>

Endovascular stent-graft repair for Stanford type A aortic dissection with extra-anatomic bypass / 中华外科杂志

<p><b>UNLABELLED</b>OBJECTIVE To evaluate the effects of endovascular stent-graft repair for Stanford type A aortic dissection combined with extra-anatomic bypass.</p><p><b>METHODS</b>To perform endovascular repair for Stanford type A aortic dissection, we tried to extend the landing zone by extra-anatomic bypass to reconstruct the innominate artery, the left common carotid artery or the left subclavian artery, and then achieved the process immediately or at a secondary stage via either the carotid or the femoral approach.</p><p><b>RESULTS</b>Thirty-four patients with ascending aortic dissection (n=8) and aortic arch dissection (n=26) were treated with this technique. Thirty three patients were successfully done aortic endovascular repair, only one died during the operation. The thirty-day mortality rate was 8.8% (3/34), endoleak incidence rate was 11.8% (4/34) and incidence rate of cerebral infarction was 5.9% (2/34). Twenty-nine patients were followed-up for 6-70 months (mean, 24. 5 months). Complete (n=16) and partial (n=13) thrombosis of the false lumen were showed with CT angiography and/or vascular color Doppler ultrasound scanning.</p><p><b>CONCLUSIONS</b>Endovascular stent-graft repair combined with extra-anatomic bypass can be a novel option for Stanford type A aortic dissection; it is safe, less invasive, and with fewer complications. Nevertheless, indications need further consideration.</p>

Effect of external vavuloplasty of deep vein in the treatment of chronic venous insufficiency of lower extremity / 中华外科杂志

<p><b>OBJECTIVE</b>To verify the role and effect of external vavuloplasty in the treatment of chronic venous insufficiency (CVI) of lower extremity.</p><p><b>METHODS</b>Thirty patients with CVI of bilateral lower extremities were enrolled to accept surgical management of vein systems. Both limbs of each patient were randomized into two groups respectively according to the operating style. One limb was given external vavuloplasty of the superficial femoral vein and surgery of superficial venous system (group A), the another limb was only given the surgery of superficial venous system (group B). The effect comparison between both limbs of each patient and two groups by color duplex scanning, color doppler velocity profile (CDVP), air plethysmography and CEAP score system one month and 3 years after operation.</p><p><b>RESULTS</b>All 60 limbs of 30 cases were CEAP C(2)-C(4) with degree III reflux (Kistner's method) in the deep veins confirmed by color duplex scanning and venography. In 1 month and 3 years after surgery, all the indexes of the limb in the group A were dramatically improved compared with those of the limbs in the group B. The average value of venous reflux degree, reflux volume, and venous filling index (VFI) had significant difference between the two groups (P < 0.001). In 3 years after surgery, there was significant difference between the two groups on ejective fraction (EF)and residual volume fraction (RVF) (P < 0.05) and CEAP clinical score (P < 0.001).</p><p><b>CONCLUSION</b>External vavuloplasty of deep vein may reduce the reflux volume of the affected deep vein and improve the valve function, and can result in better outcomes when combined with surgery of the superficial venous system.</p>

Single or staged endovascular stent-graft repair for aortic dissection with multi-tears / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the single or staged endovascular stent-graft repair for aortic dissection with multi-tears.</p><p><b>METHODS</b>The stent-grafts were inserted through the femoral artery to seal the tears of dissection.</p><p><b>RESULTS</b>Between January 2001 and June 2004, 8 patients with aortic dissection underwent stent-graft placement. There were 5 tears in one patient, 4 tears in two patients, 3 tears in two patients and 2 tears in three patients. There were 11 tears located at descending thoracic aorta, 11 at abdominal aorta and 4 at iliac artery. Six patients underwent operation in single stage, and 2 in staged maneuver. Total 23 stent-grafts were used, including 20 straight type grafts and 3 bifurcated grafts. Placement of the stent-graft was technically successful in all patients. Follow-up with CT or MRA examination after 3, 6, 12 and 24 months postoperatively showed the dissection disappeared with thrombosis in the false lumen, no endoleak occurred. All patients survived to present.</p><p><b>CONCLUSION</b>Single or staged endovascular stent-graft repair is a promising, safe and effective procedure for aortic dissection with multi-tears.</p>

Endovascular stent-graft exclusion of giant and long-segment thoracic aortic aneurysms / 中华外科杂志

<p><b>OBJECTIVE</b>To discuss the availability of endovascular stent-graft exclusion in giant and long-segment thoracic aortic aneurysms.</p><p><b>METHODS</b>Endovascular stent-graft exclusion was performed on 3 male patients with giant and long-segment thoracic aortic aneurysm. Multiple stent-grafts were connected as a long stent-graft to repair these thoracic aortic aneurysms, of which one with 28 cm in length and 7.3 cm in maximum diameter was excluded by 4 stent-grafts with different diameters and same length of 130 mm. The preliminary bypass between right common carotid artery and left common carotid artery or left common carotid artery and left subclavian artery was performed on 2 patients.</p><p><b>RESULTS</b>Three patients underwent the operation successfully, and achieved the good results. There was no endoleak at the conjunction of stent-grafts in 2 cases, and a little endoleak in 1 case, which disappeared 1 year after operation. One case presented temporal cerebral ischemia, which disappeared after 1 month.</p><p><b>CONCLUSIONS</b>The endovascular deployment with multiple stent-grafts connection is a safe, mini-invasive and effective therapeutic method for giant and long-segment thoracic aortic aneurysm, but long-term outcomes will be gotten after the follow-up study.</p>

Endovascular stent-graft exclusion on aortic dissection and dissecting aneurysm / 中华外科杂志

<p><b>OBJECTIVE</b>To study the techniques and therapeutic effects of endovascular stent-graft exclusion in aortic dissection and dissecting aneurysm.</p><p><b>METHODS</b>The clinical data of 20 cases with aortic dissection and(or) dissecting aneurysm were analysed. Stanford A dissection was found in 2 cases, in which one had a tear entry on ascending aorta. Stanford B dissection was found in 18 cases. Five patients had two or more tear entries in different sites. Endovascular polyester-covered stent-graft exclusion was performed in all cases, of which, one case was also given fenestration and graft replacement and one subjected to Y graft bypass from ascending aorta to the left common carotid artery and left subclavian artery before endovascular stent-graft exclusion.</p><p><b>RESULTS</b>No one died in operation. One patient died of heart infarction on the third day after operation. During the followup of 1 - 20 months, 19 patients were alive well (95%). The aortic dissections and(or) dissecting aneurysms of all the patients disappeared without endoleaks and organ or limb ischemia.</p><p><b>CONCLUSION</b>Endovascular stent-graft exclusion with high successful rate, low mortality and high survival rate, is simple, safe and effective in treating aortic dissection and dissecting aneurysm.</p>