Matthias Widmer

Self-Made Pericardial Tube Graft: A New Surgical Concept for Treatment of Graft Infections After Thoracic and Abdominal Aortic Procedures

BACKGROUND The aim of this study was to evaluate a new surgical concept for the treatment of graft infections after operation or endovascular treatment of thoracic, thoracoabdominal, and abdominal aortic diseases. METHODS Between 2004 and 2011, 15 patients (mean age 72 ± 10 years, 87% men) with prosthetic graft or endovascular graft infection were treated with complete removal of the infected prosthetic material, extensive debridement of the surrounding tissues, and orthotopic vascular reconstruction with self-made xenopericardial tube grafts constructed from a patch. Perioperative and long-term outcomes were evaluated. RESULTS Perioperative mortality was 27% (n = 4). All deaths were due to multiorgan failure resulting from uncontrolled septicemia from the local infectious process. Mean observational follow-up was 24 months (5 to 83 months). Control computed tomographic scans showed normal findings at the operative site in all patients. Antibiotic treatment was continued for a mean of 6 months. Freedom from reinfection was 100%. Freedom from reoperation was also 100%. CONCLUSIONS Treatment of graft infections after operation or endovascular treatment of thoracic, thoracoabdominal, and abdominal aortic diseases by complete removal of the infected prosthetic material and extensive debridement as well as orthotopic vascular reconstruction using self-made xenopericardial tube grafts as neoaortic segments provides excellent results with regard to durability and freedom from reinfection and reoperation. This new concept is an additional alternative to cryopreserved homografts that extends the armamentarium for treating patients with these highly complex conditions.

Arteriolization of Capillaries and FGF-2 Upregulation in Skeletal Muscles of Patients with Chronic Peripheral Arterial Disease

Objective: Microvascular changes in ischemic skeletal muscle are described derived from patients with long‐lasting peripheral arterial disease (PAD).

Common femoral artery: Uncommon aneurysms

Background and Aims: Femoral artery aneurysms are rare. Their natural history, tendency to embolize or rupture are not well known. Material and Methods: Data of all patients seen 1996–2002 with femoral artery aneurysms at the Swiss Cardiovascular Center were analysed. Nine patients with 13 aneurysms of the common femoral artery (CFA) were identified. Only true aneurysms with a diameter of at least 2.5 cm were included. All patients were male, mean age 70 years (range: 57–85 years). Four patients had bilateral femoral aneurysms. Risk factors included hypertension (9/9), smoking (7/9). One of the aneurysms was palpable in 5/9. Four patients were asymptomatic, 5 had Fontaine class II claudication. Five patients also had an aortic aneurysm (AAA), one a thoracic aneurysm; and 6/9 popliteal aneurysms. In all patients, diagnosis was confirmed with duplex scan. Angiography was performed preoperatively. Results: The aneurysms were operated on electively using aneurysm secclusion and interposition grafting. There were no significant perioperative complications. Median hospital stay was 8 days. Conclusion: CFA aneurysms are rare. They are palpable in nearly half of the cases. They rarely cause thrombotic or embolic complications, but are almost always connected to other aneurysms. Patients with CFA aneurysms should be screened with duplex scan. Operative therapy is straightforward, few complications can be expected. Postoperative follow-up with annual duplex scans is suggested.

Cystic adventitial degeneration: Ectopic ganglia from adjacent joint capsules

Cystic adventitial degeneration is a rare non-atherosclerotic cause of peripheral arterial occlusive disease, mainly seen in young men without other evidence of vascular disease. Diagnosis will be established by clinical findings and by ultrasound or angiography and can be treated by excision or enucleation of the affected arterial segment or by percutaneous ultrasound-guided aspiration. However, the etiology of adventitial cysts remains unknown. We report a case of cystic adventitial degeneration showing a connection between the joint capsule and the adventitial cyst, supporting the theory that cystic adventitial degeneration may represent ectopic ganglia from adjacent joint capsules.

Arteriovenous access ischemic steal (AVAIS) in haemodialysis: a consensus from the Charing Cross Vascular Access Masterclass 2016

Arteriovenous access ischaemic steal (AVAIS) is a serious and not infrequent complication of vascular access. Pathophysiology is key to diagnosis, investigation and management. Ischaemia distal to an AV access is due to multiple factors. Clinical steal is not simply blood diversion but pressure changes within the adapted vasculature with distal hypoperfusion and resultant poor perfusion pressures in the distal extremity. Reversal of flow within the artery distal to the AV access may be seen but this is not associated with ischaemia in most cases. Terminology is varied and it is suggested that arteriovenous access ischemic steal (AVAIS) is the preferred term. In all cases AVAIS should be carefully classified on clinical symptoms as these determine management options and allow standardisation for studies. Diabetes and peripheral arterial occlusive disease are risk factors but a ‘high risk patient’ profile is not clear and definitive vascular access should not be automatically avoided in these patient groups. Multiple treatment modalities have been described and their use should be directed by appropriate assessment, investigation and treatment of the underlying pathophysiology. Comparison of treatment options is difficult as published studies are heavily biased. Whilst no single technique is suitable for all cases of AVAIS there are some that suit particular scenarios and mild AVAIS may benefit from observation whilst more severe steal mandates surgical intervention.

Generalized dilating diathesis in patients with popliteal arterial aneurysm

BACKGROUND Aim of this study was to analyse the relationship between popliteal artery aneurysm (PAA) and generalized arteriomegaly. PATIENTS AND METHODS In this consecutive serie, thirty-three patients (1 woman, mean age 69.7 +/- 9.6 years) undergoing PAA repair between 1996 and 2000 agreed to participate in a duplex screening program to assess the diameters of the infrarenal abdominal aorta, common and external iliac, common and superficial femoral and contralateral popliteal arteries as well as common carotid and brachial arteries. RESULTS The prevalence of arteriomegaly and aneurysmal disease, respectively, was as follows: abdominal aorta 15/33 (45.5%) and 8/33 (24.2%), common iliac artery 34/66 (51.5%) and 23/66 (34.8%), common femoral artery 55/66 (83.3%) and 7/66 (10.6%) as well as contralateral popliteal artery 7/33 (21.2%) 15/33 (45.5%). Significantly larger carotid artery diameters were found comparing PAA patients with age- and body surface adjusted healthy controls (p < 0.001). Furthermore, patients with multiple peripheral arterial aneurysms had significantly larger diameters of the brachial (p < 0.02) and external iliac (p < 0.005). CONCLUSIONS Our findings support the hypothesis of a diathesis for a generalized arteriomegaly with a predilection for further aneurysms of the abdominal aorta, iliac arteries, femoral and contralateral popliteal arteries in patients with PAA.

Effects of low abdominal blood flow and dobutamine on blood flow distribution and on the hepatic arterial buffer response in anaesthetized pigs

ABSTRACT Low cardiac output impairs the hepatic arterial buffer response (HABR). Whether this is due to low abdominal blood flow per se is not known. Dobutamine is commonly used to increase cardiac output, and it may further modify hepatosplanchnic and renal vasoregulation. We assessed the effects of isolated abdominal aortic blood flow changes and dobutamine on hepatosplanchnic and renal blood flow. Twenty-five anesthetized pigs with an abdominal aorto-aortic shunt were randomized to 2 control groups [zero (n = 6) and minimal (n = 6) shunt flow], and 2 groups with 50% reduction of abdominal blood flow and either subsequent increased abdominal blood flow by shunt reduction (n = 6) or dobutamine infusion at 5 and 10 &mgr;g kg−1 min−1 with constant shunt flow (n = 7). Regional (ultrasound) and local (laser Doppler) intra-abdominal blood flows were measured. The HABR was assessed during acute portal vein occlusion. Sustained low abdominal blood flow, by means of shunt activation, decreased liver, gut, and kidney blood flow similarly and reduced local microcirculatory blood flow in the jejunum. Shunt flow reduction partially restored regional blood flows but not jejunal microcirculatory blood flow. Low-but not high-dose dobutamine increased gut and celiac trunk flow whereas hepatic artery and renal blood flows remained unchanged. Neither intervention altered local blood flows. The HABR was not abolished during sustained low abdominal blood flow despite substantially reduced hepatic arterial blood flow and was not modified by dobutamine. Low-but not high-dose dobutamine redistributes blood flow toward the gut and celiac trunk. The jejunal microcirculatory flow, once impaired, is difficult to restore.

Polytetrafluoroethylene and bovine mesenterial vein grafts for hemodialysis access: a comparative study

PURPOSE This study aimed to evaluate the safety and patency rate of bovine mesenterial vein grafts (BMVG) for vascular access (VA) in hemodialysis patients (HDP), compared to expanded polytetrafluorethylene (ePTFE grafts) over a mid- to long-term period. METHODS Patency and complication rate of 23 consecutive HDP with BMVG for VA were compared to a control group consisting of 23 similar HDP with ePTFE grafts. In both groups, the graft was placed preferably in a forearm loop configuration. The same surgeon performed all procedures. All patients were followed over a period of 4 yrs. RESULTS Graft placement was successful in all patients. Patency rates did not differ significantly in both groups. However, there were less severe complications in the BMVG group. CONCLUSION The BMVG is a viable alternative for HD access in patients where autologous construction is not possible, and should be given priority in patients with a failed ePTFE graft or high risk for infection.

Editor's Choice – Vascular Access: 2018 Clinical Practice Guidelines of the European Society for Vascular Surgery (ESVS)

The European Society for Vascular Surgery (ESVS), in line with its mission, appointed the Vascular Access (VA) Writing Committee (WC) to write the current clinical practice guidelines document for surgeons and physicians who are involved in the care of patients with haemodialysis (HD) and VA. The goal of these Guidelines is to summarise and evaluate all the currently available evidence to assist physicians in selecting the best management strategies for all patients needing VA or for pathologies derived from a VA.

Simulation in vascular access surgery training

Rapidly growing technical developments and working time constraints call for changes in trainee formation. In reality, trainees spend fewer hours in the hospital and face more difficulties in acquiring the required qualifications in order to work independently as a specialist. Simulation-based training is a potential solution. It offers the possibility to learn basic technical skills, repeatedly perform key steps in procedures and simulate challenging scenarios in team training. Patients are not at risk and learning curves can be shortened. Advanced learners are able to train rare complications. Senior faculty members presence is key to assess and debrief effective simulation training. In the field of vascular access surgery, simulation models are available for open as well as endovascular procedures. In this narrative review, we describe the theory of simulation, present simulation models in vascular (access) surgery, discuss the possible benefits for patient safety and the difficulties of implementing simulation in training.