Can concomitant above-knee femoropopliteal bypass with artificial graft affect the outcome of femorofemoral bypass with artificial graft?

Objectives Few have studied the effect of concomitant femoropopliteal (FEM-POP) bypass surgery on the outcome of femorofemoral (FEM-FEM) bypass in patients with peripheral arterial disease (PAD). This study was aimed to analyze the risk relationship of concomitant FEM-POP bypass on the patency of FEM-FEM bypass. Methods From March 2009 to April 2020, a total of 27 patients who underwent FEM-FEM bypass surgery using polytetrafluoroethylene grafts were retrospectively analyzed according to concomitant FEM-POP bypass surgery. The mean follow-up duration was 38.20 ± 34.56 months. Results The overall primary patency of the FEM-FEM bypass grafts in all 27 patients was 83.7, 78.5, and 72.0 at one, two, and 3 years, respectively. The overall limb salvage rate was 100, 94.1, and 86.9 at one, two, 3 years, respectively. Among them, ten patients underwent FEM-FEM bypass only (group 1). The other 17 patients needed a concomitant FEM-POP bypass and these patients were classified into three groups (group 2, ipsilateral FEM-POP, n = 5; group 3, crossover FEM-POP, n = 6; and group 4, bilateral FEM-POP, n = 6) The comparison of the primary patency of group 1 with the concomitant FEM-POP groups (sum of groups 2, 3, and 4, that is, group 5, n = 17) revealed a statistically significant improved patency for FEM-FEM bypasses not requiring concomitant infra-inguinal bypass ( p = .036). Among the concomitant FEM-POP groups, group 2 had the lowest primary patency of the FEM-FEM bypass significantly ( p = 0.07). The limb salvage rate of group 4 was significantly low. Conclusions A concomitant FEM-POP bypass influenced the outcome of FEM-FEM bypass surgery. In conclusion, compromised infra-inguinal runoff at either extremity requiring concomitant FEM-POP bypass significantly worsens long-term FEM-FEM bypass patency. In addition, a concomitant bilateral FEM-POP bypass is a risk factor affecting the limb salvage rate in FEM-FEM bypass.

Eliminating Vascular Obstruction in Myocardial Infarction by Accelerated Ferromagnetic Microrobot

Background vascular obstruction by clots is one of the main reasons of cardiovascular disease such as myocardial infarction. There is a short time, less than 6 minutes, to establish the blood flow, especially in vital organs. While conventional techniques are not very fast and effective, current micro-robots have inherent limitations such as being slow to achieving this goal. Objective There is a strong requirement to develop microrobots with new principles that can quickly eliminate clot blockage in the vascular. The aim of this study is to evaluate, in-vitro, the efficiency of accelerated ferromagnetic micro-robots in destroying blood clots in an artificial vascular precipitately. Methods An artificial graft with a diameter of 10 mm were used as the vessel. Blood clots with various lengths (5*10 and 10*10 and 20*10mm3 (dimeter*length)) are formed inside the graft. Microrobots made of steel with a length of 1 mm and a width of 0.05 mm are utilized. Besides, an electromagnetic accelerator is prototyped to instantly raise the magnetic field, which accelerates the magnetic micro-robot toward the blocked artery. Blood clots with various lengths (5*10 and 10*10 and 20*10mm3(Dimeter*length)) are formed inside the tube. The effect of voltage from 100 to 400 volts on destroying different lengths of clot has been studied. Results The microrobot enables to destroy the clot and reopen the vessel in a fraction of a second. By increasing the voltage from 100 to 400 volt, the micro-robot is able to destroy clots with longer lengths from 5 to 30 mm. Conclusion results confirm that accelerated microbes have a unique potential in piercing clots to reestablish blood flow.

Modified Isolated Cerebral Perfusion Technique for Prevention of Stroke With Aortic Arch Replacement

In aortic arch replacement, an isolated cerebral perfusion method has been reported in additional to axillary artery cannulation to prevent postoperative stroke. We have made changes to this method. In other words, we devised a method to reduce cerebral embolism by performing selective cerebral perfusion via an artificial graft anastomosed to the left common carotid artery and the left subclavian artery. This method was performed in 7 cases, and all patients were discharged alive without any neurological disorders. In the surgical procedure of the aortic arch, sufficient care must be taken in the manipulation around the brachiocephalic artery and the left subclavian artery. Our method can avoid reinsertion due to desorption of the cerebral perfusion cannula and can be expected to prevent postoperative stroke.

Bio-Inspired Design of a Porous Resorbable Scaffold for Bone Reconstruction: A Preliminary Study

The study and imitation of the biological and mechanical systems present in nature and living beings always have been sources of inspiration for improving existent technologies and establishing new ones. Pursuing this line of thought, we consider an artificial graft typical in the bone reconstruction surgery with the same microstructure of the bone living tissue and examine the interaction between these two phases, namely bone and the graft material. Specifically, a visco-poroelastic second gradient model is adopted for the bone-graft composite system to describe it at a macroscopic level of observation. The second gradient formulation is employed to consider possibly size effects and as a macroscopic source of interstitial fluid flow, which is usually regarded as a key factor in bone remodeling. With the help of the proposed formulation and via a simple example, we show that the model can be used as a graft design tool. As a matter of fact, an optimization of the characteristics of the implant can be carried out by numerical investigations. In this paper, we observe that the size of the graft considerably influences the interaction between bone tissue and artificial bio-resorbable material and the possibility that the bone tissue might substitute more or less partially the foreign graft for better bone healing.

An aorto-oesophageal fistula treated with total arch repair combined with oesophageal repair

Aorto-oesophageal fistula is a rare but fatal disease. Open surgical repair or endotube repair of aorta and oesophagus save patients from circulatory deterioration, major haematemesis and severe infection. Here we present a rare case of an aorto-oesophageal fistula in the right hemi-arch caused by a fish bone treated with an alternative surgical strategy. Total aortic arch repair using the frozen elephant trunk procedure combined with oesophageal repair were performed. No aortic fistula, oesophageal fistula or artificial graft infection occurred in the follow-up.

Primary Aortoenteric Fistulae: What Every Surgeon Should Know About Its Diagnosis and Treatment

Aortoenteric fistula is a rare finding that is potentially fatal and is usually seen as a fistula between the aorta or an aortic graft and the third part of the duodenum. The type without the presence of an artificial graft is considered as primary and the other type as secondary. The patients usually present with the heralding symptom of minor hematemesis, which later leads to massive and mortal GI bleeding. The most important factor in the diagnosis of an aortoenteric fistula is to have a high clinical suspicion after taking an appropriate and accurate history. In hemodynamically stable patients with clinical suspicion, performing an intravenouscontrast-CT scan of the abdomen and pelvis is of assistance in diagnosis. In general, stable hemodynamics greatly reduces the suspicion for diagnosis. Treatment is often surgical, and in regard to the severity of abdominal contamination or the level of visible infection, the extra anatomical or insitu graft repair is considered as the method of choice. This article tries to transfer our experiences in two patients, each of whom presented with hematemesis and melena without a history of underlying aortic aneurysm.

Zone 0 Thoracic Endovascular Repair After Aortic Wrapping for Acute Aortic Syndrome

We report a successful treatment of type A acute aortic syndrome (AAS)-associated aortic arch aneurysm in a 71-year-old man with major comorbidities. The ascending aorta was wrapped with artificial graft, and supra-aortic debranching was constructed. Then, Zone 0 thoracic endovascular aneurysm repair (TEVAR) with plug occlusion of the left subclavian artery was successfully performed. The patient was discharged in good physical condition without any complications. To our knowledge, this is the first reported case in the literature of successful Zone 0 TEVAR after ascending aorta wrapping and supra-aortic debranching with type A AAS associated with aortic arch aneurysm.

The Giant Post-Traumatic Diaphragmatic Hernia: Clinical Case and Literature Review

The post-traumatic diaphragmatic hernia is a rare type of trauma which most commonly occurs after the blunt trauma of the thorax and abdomen. In the acute period of trauma, the symptoms of the emergency diseases and nonspecific signs of the diaphragmatic rupture are the reasons of frequent diagnostic mistakes. A missed diaphragmatic rupture grows in time and leads to migration of organs from the abdominal cavity to the thoracic one due to pressure gradient. The symptoms of diaphragmatic hernia are not expressed and the duration of the asymptomatic period of the disease may vary from some years to 10 years and longer. The increasing restructuring of the abdominal wall leads to reduced abdominal cavity, which makes the standard reconstructive surgery difficult, the intraabdominal pressure grows and relapse occurs in the postoperative period. In these cases, surgeons perform complex techniques which enlarge the abdominal cavity with local tissues or an artificial graft. However, there are no clear recommendations about the extent of the abdominal wall reconstruction so that the abdominal cavity size would be adequate for organs. The authors suggested a simple method to calculate it and used it in practice. In the article, we report the clinical case of a 53-year-old woman with a giant post-traumatic diaphragmatic hernia after motor vehicle accident 48 years ago and offer an original method of treatment. The first operation including hernia resolution and repair of diaphragmatic rupture was complicated by relapse on the second day after operation due to the high intra-abdominal pressure. During the second reconstructive surgery (4 months later), the authors performed their own method of abdominal cavity enlargement and got a good result in the shortand long-term postoperative period.

The Experience of ACL Reconstruction with Synthetics Ligament: Where are we now?

The dispute on artificial ligaments used for anterior cruciate ligament (ACL) reconstruction has been a long time issue. Admittedly, due to designing defects, materials deficient without creeping, viscoelasticity and biocompatibility, and incorrect surgical technique, early application of synthetic ligament in ACL reconstruction did not yield good outcomes. For a long time, a poor outcome occupied our consensus. Whilst the poignant lessons didn’t drive people to thoroughly figure out underlying reasons but amplified the fear of synthetics ligament in the ACL reconstruction. Recent 15 years, a new generation synthetic ligament, Ligament Advanced Reinforcement System (LARS) developed for ACL/PCL reconstruction has been widely used in China. There are at least 147 papers on LARS published in Chinese and over 47 SCI papers published in English. Consistently, a positive outcome has been concluded in most reports with an early return to sports and lower complication or failure rate. Cumulative failure rate from short- and mid-term follow-ups was only 2.6% according to Batty et al., which has been commended as “surprisingly impressive” by James H. Lubowitz of journal Arthroscopy. In China, LARS ligaments have been approved by CFDA since 2004 and been used for ACL reconstruction over 30,000 cases. Recently a national multi-centers clinical investigation has been done in long-term failure analysis of the ACLR with LARS, which has involved 20 Chinese clinical centers and 1146 cases with mean follow-up time of 87 months（7 years）, organized by the Chinese Artificial Ligament Study Group (CALSG), with an acceptable outcome in failure rate of 4.5% and complication rate of 4.1%. The following factors were concluded as main failure reasons, 1）incorrect surgical technique in a non-isometric ACL reconstruction, 2）lack of the graft biocompatibility and rigid screw interface fixation, 3) non-suitable indicated patients’ selection and rehabilitation program. Compared with reported long-term failure rate in auto（10%）or in allografts（24%）, the outcome of Synthetic ligament was more superior and acceptable results. Moreover, the functional evaluation and return to sports of the patients were also high satisfying, despite some complication, such as screw loose, remnant stimulation but very rear synovitis. Non-isometric tunnel position was the main failure reason which caused by surgeons tech. An ISOMETRIC surgical technique should be stressed especially in ACL reconstruction using synthetic, focused on surgeon education, instead of simply blaming the artificial graft. Based on the systemic review and our study, a modification of synthetic graft has been developed successfully in experiment, graft fixation, synthetics materials modified with Polyethylene Terephthalate (PET) which has facilitated the biocompatibility. Our clinical investigation has also focused on a near-isometric ACL reconstruction, which would decrease the graft tunnel motion and facilitate artificial graft successful. Non-isometric input will predispose the grafts easy failure because of over tension on the graft while joint moving. Carefully selected patients, proper surgical technique, and standard rehabilitation program will ensure artificial ligament successfully. We will keep devoting to innovate artificial ligaments, including tissue engineering, bio-mimics design, advanced fixation, hybrid graft designing and more precise Isometric surgical technique. Never forgetting our beginning mind, the artificial ligaments will open a new epoch in the future of ACL reconstruction.