0000000000005247
AUTHOR
Bernhard Dorweiler
Value of the deep femoral artery as alternative inflow source in infrainguinal bypass surgery.
Background The purpose of this study was to analyze the long-term results of infrainguinal bypass surgery using the deep femoral artery (DFA) as the inflow source. Methods Between 1998 and 2011, 88 bypasses of the lower limb were placed in 86 patients (mean age 71 years) using the deep femoral artery as inflow. Patients' records were retrieved from a computerized database and analyzed retrospectively. Results Critical limb ischemia (rest pain/tissue loss) was the indication in the majority (87.5%) of cases. The distal anastomosis of the bypass grafts was located at the popliteal level in 32 cases and the tibial (pedal) level in 52 cases, respectively, with the autologous vein as conduit in …
Below knee femoropopliteal bypass with glutaraldehyde-tanned modified human umbilical vein (Dardik-Biograft) – experience with the modified prosthesis
Fur den kniegelenkuberschreitenden peripheren Bypass ist die V. saphena magna des Transplantat der ersten Wahl. Bei fehlender autologer Vene ist die denaturierte humane Umbilikalvene (HUV) neben rein synthetischen Gefasprothesen eine selten erwogene Alternative zum autologen Gefasersatz. Zur Beurteilung ihrer langfristigen Bypassfunktion und degenerativer Veranderungen erfolgte bei nicht geeigneter V. saphena magna die Verwendung der denaturierten humanen Umbilikalvene bei kniegelenkuberschreitenden femoropoplitealen Bypassoperationen. Bei 54 Patienten wurden 55 kniegelenkuberschreitende femoropopliteale Bypassoperationen mit Umbilikalvene durchgefuhrt. Die Operationsindikation bestand uber…
External polytetrafluoroethylene reinforcement of varicose autologous vein grafts in peripheral bypass surgery produces durable bypass function
Abstract Objective Use of autologous veins as peripheral bypass graft may become critical in the presence of significant varicose degeneration of the harvested vein. External support of such dilated veins with standard polytetrafluoroethylene (PTFE) prostheses was recommended as an option to use these veins for peripheral bypass. A single-center experience with this technique regarding long-term graft function, secondary reinterventions, and potential graft degeneration is presented. Methods Between January 1995 and January 2006, there were 54 patients with varicose veins who underwent 57 consecutive infrainguinal vein bypass operations with PTFE reinforcement in 57 limbs. Indications for s…
A novel in vitro model for the study of plaque development in atherosclerosis
SummaryFor the study of atherogenesis in vitro, coculture systems have been devised, in which two or more cell types can be cultured in close contact to each other. Herein, we describe a novel in vitro model that aims at the simulation of the morphology ofa normal muscular artery allowing for the study of the initial events in atherosclerosis. Usinga modified fibrin gel as a scaffold for the coculture of endothelial cells (ECs) and smooth muscle cells (SMCs), we generated an autologous in vitro model with a multilayer growth of SMCs (intima-like structure) covered by an endothelium. The production of extracellular matrix (ECM) could be visualized histologically and verified by (i) ascorbic-…
Intérêt des fistules artérioveineuses pour les pontages distaux à haut-risque d’échec précoce
Les resultats des fistules arterioveineuses adjuvantes (FAV) dans la chirurgie de pontage en cas de mauvaise artere receveuse, de flux peroperatoire severement altere, ou de revision pour defaillance precoce et restauration du flux ont ete analyses dans une etude retrospective. De janvier 1998 a decembre 2006, 24 FAV adjuvantes ont ete construites sur la veine autologue ou des pontages distaux composites ayant un mauvais debit peroperatoire, une mauvaise artere pedieuse, ou en cas de reprise precoce de pontage reussie pour empecher un echec de pontage. Toutes les revascularisations sous-inguinales etaient enregistrees dans une base de donnees automatisee prospective. Les pontages distaux av…
Patency of renal and visceral vessels after open thoracoabdominal aortic replacement.
Objective In thoracoabdominal aortic aneurysms (TAAAs), a paradigm shift is observed from open surgery toward total endovascular aortic repair using fenestrated and branched endografts. Whereas outcome after open replacement in terms of mortality and paraplegia has been evaluated extensively, no studies exist addressing long-term patency of visceral and renal vessels. To enable comparison of target vessel patency between open and endovascular treatment, we analyzed our series of open TAAA replacements. Methods Our vascular surgery database was screened for patients who received open TAAA replacement between 1998 and 2012, and patient records were analyzed retrospectively. All available imag…
Pedale Bypasschirurgie bei diabetischen Fußsyndrom: Indikation, Technik und Ergebnisse
Die periphere arterielle Verschlusskrankheit des diabetischen Patienten ist bevorzugt durch einen langstreckigen Verschluss der Unterschenkelarterien uner teilweiser Aussparung der Fusarterien gekennzeichnet. Aufgrund der begleitenden Polyneuropathie und der erhohten Infektanfalligkeit besteht fur diese Patienten ein dramatisch erhohtes Amputationsrisiko. Dieses Verschlussmuster ermoglicht aber die Anlage pedaler Venenbypasse speziell auch unter Uberbruckung kurzerer Distanzen als sog. “distal origin bypass”.
Endovascular treatment of acute bleeding complications in traumatic aortic rupture and aortobronchial fistula.
Objective: Herein we report our experience in placement of endovascular stentgrafts in the descending aorta in patients with acute bleeding complications due to traumatic rupture or aortobronchial fistula. Methods: Six patients (one woman, five men, mean age 47 ^ 19 years) were treated from September 1995 to February 2000 by implantation of endovascular stentgrafts in the descending aorta. Indications included traumatic ruptures of the aortic isthmus (na 3) and aortobronchial fistulas (na 3). All procedures were performed under general anaesthesia. The implants were introduced under fluoroscopic guidance via the aorta (na 1), the iliac (na 4) or femoral (na 2) artery, respectively. Results:…
Arterial Embolism to the Upper Extremity in a Patient with Factor V Leiden Mutation (APC Resistance)
Factor V Leiden mutation has emerged as one of the leading abnormalities in inherited blood coagulation disorders, resulting in a markedly increased risk for deep leg vein thrombosis. A 24- year-old woman presented with acute onset of critical ischemia of her left thumb and index finger. Intraarterial angiography revealed an embolus in the distal radial artery and a thrombotic occlusion of the digital artery of the thumb and index finger. Immediate therapy encompassed a selective surgical embolectomy of the distal radial artery followed by a local intraarterial lysis that was continued for 3 days. Additionally, therapeutic anticoagulation and vasodilating drugs (prostaglandin E) were admin…
Ovine Biosynthetic Grafts for Aortoiliac Reconstructions in Nonsterile Operative Fields.
Abstract Background Prosthetic vascular grafts placed surgically or via endovascular techniques can be subject to the risk of life-threatening graft infections. The Omniflow II vascular prosthesis is a biosynthetic graft that was reported to have favorable properties in resisting infections. Materials and Methods We retrospectively reviewed our 3 years' experience of using the Omniflow II prostheses for aortoiliac reconstructions in patients considered to carry a substantial risk of subsequent prosthetic graft infections (prevention group) as well as in patients with actively infected prosthetic vascular grafts (treatment group). Results Aorto-bi-iliac (n = 4) and aortobifemoral (n = 12) va…
Extremitätenerhalt durch pedalen In-situ-Bypass beim diabetischen Fußsyndrom
INTRODUCTION: Treatment of the ischemic diabetic foot syndrome still represents a medical and economic challenge. Contrary to the aims of the Saint Vincent declaration a dramatic reduction of major amputations in Germany was not noted, although in the diabetic patients the predominant type of tibial artery occlusion allows construction of pedal bypasses for limb salvage. METHOD: In patients with ischemic diabetic foot syndrome following angiographic evaluation of the ischemic limb, the indication for surgical revascularisation of patent pedal arteries was established. The in-situ technique was preferred in the presence of a suitable ipsilateral greater saphenous vein whenever possible. Reva…
VS07�EXCELLENT LATE OUTCOME WITH DENATURATED HUMAN UMBILICAL VEIN (HUV) IN FEMOROPOPLITEAL BYPASS SURGERY - A GOOD EXAMPLE FOR THE IMPORTANCE OF BIOLOGICAL MATERIALS IN VASCULAR SURGERY
Purpose: Femoropopliteal bypass with autologous vein provides excellent long term results in lower limb bypass. In case of unsuitable vein generally synthetic PTFE prostheses are preferred. Denaturated human umbilical vein was used as femoropopliteal bypass graft when autologous vein was not available. Long term results of a consecutive single center series are presented. Methodology: HUV was implanted in femoropopliteal position in case of unavailable vein for symptomatic peripheral vascular disease or popliteal aneurysm. Follow-up examinations were performed after 3, 6, 12, 18, 24 months and annually thereafter. Duplex scan was used for detection of potential biodegeneration of the HU…
Treating iliac aneurysm using the Nellix Endovascular Sac Sealing System.
As endovascular treatment of abdominal aortic aneurysms has become established, there has been growing focus on treatment of the aneurysmal iliac artery. Isolated, large iliac aneurysms >30 mm pose a risk of rupture, but, in addition, 20% to 30% of abdominal aortic aneurysms are associated with iliac aneurysmal dilatation, which can compromise long-term outcomes. Endovascular solutions are evolving and until recently have utilized standard stent graft technology. The endovascular aortic sealing system was introduced as a new, effective method for the treatment of infrarenal aortic aneurysms. In this article, we present our recent extended use of the Nellix system, with or without a combinat…
Atherogenic properties of enzymatically degraded LDL: selective induction of MCP-1 and cytotoxic effects on human macrophages.
Abstract —The mechanisms underlying the selective accumulation of macrophages in early atherosclerotic lesions are poorly understood but are likely to be related to specific properties of altered low density lipoprotein (LDL) deposited in the subendothelium. Enzymatic, nonoxidative degradation of LDL converts the lipoprotein to a potentially atherogenic moiety, enzymatically altered LDL (E-LDL), which activates complement and is rapidly taken up by human macrophages via a scavenger receptor–dependent pathway. Immunohistological evidence indicates that E-LDL is present in an extracellular location in the early lesion. We report that E-LDL causes massive release of monocyte chemotactic prote…
Use and durability of femoral vein for autologous reconstruction with infection of the aortoiliofemoral axis.
Objective To analyze early and late mortality, venous morbidity, reinfection, and freedom from reintervention after using the femoral vein (FV) for vascular reconstruction with infection of the aortoiliofemoral axis. Methods By reviewing our database, 86 patients could be identified with implantation of FV grafts in infected fields between November 1995 and July 2012. The patient records were retrospectively analyzed and follow-up information obtained from patients or their general physician. Seventy-one patients presented with prosthetic graft infection and 15 with an infected aneurysm. For data analysis, patients were divided into an aortoiliac (n = 67) and a femoral group (n = 19). Study…
Questionable Value of Adjuvant Arteriovenous Fistula in Pedal Bypass at High Risk for Early Failure
Results of an adjuvant arteriovenous fistula (AVF) in pedal bypass surgery in the presence of poor status of the recipient artery, severely impaired intraoperative runoff, or revision for early failure and flow restitution were analyzed in a retrospective study. From January 1998 to December 2006, 24 adjuvant AVFs were constructed in autologous vein or composite pedal bypasses with low intraoperative bypass flow, poor status of the pedal artery, or during successful early bypass revision to prevent graft failure. All infrainguinal bypass operations were registered in a computerized database and prospectively followed. Pedal bypasses with adjunctive AVF were reviewed for fistula function, gr…
Preoperative Planning for Guidewires Employing Shape-Regularized Segmentation and Optimized Trajectories
Upcoming robotic interventions for endovascular procedures can significantly reduce the high radiation exposure currently endured by surgeons. Robotically driven guidewires replace manual insertion and leave the surgeon the task of planning optimal trajectories based on segmentation of associated risk structures. However, such a pipeline brings new challenges. While Deep learning based segmentation such as U-Net can achieve outstanding Dice scores, it fails to provide suitable results for trajectory planning in annotation scarce environments. We propose a preoperative pipeline featuring a shape regularized U-Net that extracts coherent anatomies from pixelwise predictions. It uses Rapidly-ex…
"3D Printed Complexed Arota as A Preoperative Guidance and Postoperative Results’ Evaluation"
We describe a case of 55 years old female who underwent an aortic valve replacement using a mechanical valve...
Infrapopliteal Composite Bypass with Autologous Vein and Second Generation Glutaraldehyde Stabilized Human Umbilical Vein (HUV) for Critical Lower Limb Ischaemia
Objective. To audit a single center consecutive series of infrapopliteal composite bypasses with second generation glutaraldehyde stabilized human umbilical vein. Design. Retrospective study. Patients. From January 1996 to July 2006 89 femoro-distal bypasses were constructed in 85 patients with HUV and residual vein segments as composite grafts in the absence of sufficient length of autologous vein. Methods. All patients with infrainguinal bypass operations were registered prospectively. Bypasses to infrapopliteal arteries performed with HUV-composite grafts were reviewed for graft patency, limb salvage, patient survival and possible biodegeneration of the HUV. Results. Early graft thrombos…
Subendothelial infiltration of neutrophil granulocytes and liberation of matrix-destabilizing enzymes in an experimental model of human neo-intima.
SummaryIt was the objective of this study to examine the role of human neutrophil granulocytes (PMN) in an in-vitro model of human neo-intima developed for the study of atherosclerosis. Human granulocytes were subjected to a co-culture model of human endothelial and smooth muscle cells. Subendothelial lipid accumulation was achieved by addition of native LDL to the culture medium. Tissue samples were analyzed by immunohistochemistry and scanning/transmission electron microscopy, and culture supernatants were examined for the presence of interleukin- 8 (IL-8), MCP-1, GRO-α, elastase and matrixmetalloproteinase-8 (MMP-8). Following addition of 2 mg/ml LDL, adherence, transmigration and infilt…
Adjunct Perfusion Branch for Reduction of Spinal Cord Ischemia in the Endovascular Repair of Thoracoabdominal Aortic Aneurysms
Background To analyze utilization of a perfusion branch for temporary sac perfusion to reduce the spinal cord ischemia (SCI) in the endovascular repair of thoracoabdominal aortic aneurysms (TAAAs). Methods Between January 2012 and August 2016, 30 patients (18, men; median age 72 years) were treated for TAAAs with total endovascular repair using customized branched/fenestrated endografts in our institution. The median aneurysm size was 6.6 cm. Types of TAAA were: type I, 9 (30%), type II, 5 (16.6%), type III, 4 (13.3%), type IV, 6 (20%), and type V, 6 (20%). Ten patients received a perfusion branch to create an intentional endoleak, which was occluded with vascular plugs in mean interval ti…
Quality Control in 3D Printing: Accuracy Analysis of 3D-Printed Models of Patient-Specific Anatomy
As comparative data on the precision of 3D-printed anatomical models are sparse, the aim of this study was to evaluate the accuracy of 3D-printed models of vascular anatomy generated by two commonly used printing technologies. Thirty-five 3D models of large (aortic, wall thickness of 2 mm, n = 30) and small (coronary, wall thickness of 1.25 mm, n = 5) vessels printed with fused deposition modeling (FDM) (rigid, n = 20) and PolyJet (flexible, n = 15) technology were subjected to high-resolution CT scans. From the resulting DICOM (Digital Imaging and Communications in Medicine) dataset, an STL file was generated and wall thickness as well as surface congruency were compared with the original …
Utilidad cuestionable de la fístula arteriovenosa auxiliar en el bypass distal de riesgo
En un estudio retrospectivo se analizaron los resultados de la colocacion de una fistula arteriovenosa (FAV) auxiliar en la cirugia de bypass distal en presencia de una arteria receptora de mala calidad o con severa alteracion de la circulacion colateral. Desde enero de 1998 hasta diciembre de 2006, se crearon 24 FAV auxiliares en venas autologas o en bypass distales mixtos que presentaban un flujo intraoperatorio bajo, arteria distal de mala calidad, o durante la revision inicial de un bypass para prevenir su fracaso. Todas las cirugias de bypass infrainguinal se registraron en una base de datos informatizada y se realizo su seguimiento de forma prospectiva. En los bypass distales con FAV …
Der kurze popliteodistale Venenbypass beim diabetischen Fußsyndrom DFS
Purpose: World wide increase of diabetes compound with diabetic foot syndrome becomes a challenge in vascular surgery to avoid limb loss. In diabetics a special pattern of atherosclerosis is prevalent with disease limited to the infrageniculate arteries but sparing inflow vessels and distal tibial and pedal arteries. This provides short bypass grafting from popliteal to tibial and pedal arteries, a concept first described by F. Veith in 1981. Methods: Diabetics with severe atherosclerotic disease and limb-threatening ischemia got general evaluation and vascular imaging. Falling in this special category the patients underwent short vein bypass grafting originating at the first or third popli…
Durability of open popliteal artery aneurysm repair
Objective The objective of this study was to analyze our long-term results after open surgery for popliteal artery aneurysm. Methods Records of patients who received surgery between 1998 and 2010 were retrieved from a computerized database and analyzed retrospectively. End points of the study were perioperative mortality and morbidity and patency and limb salvage rate. Results Two hundred and six popliteal aneurysms (median diameter, 30 mm; interquartile range, 18 mm) were treated (161 elective, 45 emergent) in 154 patients (mean age, 67 ± 11 years) using vein grafts (82%) via the medial approach (92%). Above-knee popliteal artery (45%) and below-knee popliteal artery (65%) were the predomi…
Strategies for endovascular aortic repair in aortobronchial and aortoesophageal fistulas.
Objective To report our experience of thoracic endovascular aortic repair (TEVAR) for acute bleeding originating from the thoracic aorta in patients with aortobronchial fistula (ABF) or aortoesophageal fistula (AEF). Patients and Methods A total of nine patients (three woman) were treated from September 1995 to March 2012 by TEVAR for ABF (n = 5) and AEF (n = 4). The implants (N = 14) were introduced with fluoroscopic guidance via the aorta (n = 1), the iliac (n = 2), or femoral (n = 11) artery, respectively. Results All aortic lesions could be sealed successfully. Perioperative morbidity was 0% in the ABF group and 50% (2 of 4) in the AEF group and no procedure-related morbidity was noted …
Modular Small Diameter Vascular Grafts with Bioactive Functionalities.
We report the fabrication of a novel type of artificial small diameter blood vessels, termed biomimetic tissue-engineered blood vessels (bTEBV), with a modular composition. They are composed of a hydrogel scaffold consisting of two negatively charged natural polymers, alginate and a modified chitosan, N,O-carboxymethyl chitosan (N,O-CMC). Into this biologically inert scaffold two biofunctionally active biopolymers are embedded, inorganic polyphosphate (polyP) and silica, as well as gelatin which exposes the cell recognition signal, Arg-Gly-Asp (RGD). These materials can be hardened by exposure to Ca(2+) through formation of Ca(2+) bridges between the polyanions, alginate, N,O-CMC, and polyP…
MerTK receptor cleavage promotes plaque necrosis and defective resolution in atherosclerosis
Atherothrombotic vascular disease is often triggered by a distinct type of atherosclerotic lesion that displays features of impaired inflammation resolution, notably a necrotic core and thinning of a protective fibrous cap that overlies the core. A key cause of plaque necrosis is defective clearance of apoptotic cells, or efferocytosis, by lesional macrophages, but the mechanisms underlying defective efferocytosis and its possible links to impaired resolution in atherosclerosis are incompletely understood. Here, we provide evidence that proteolytic cleavage of the macrophage efferocytosis receptor c-Mer tyrosine kinase (MerTK) reduces efferocytosis and promotes plaque necrosis and defective…
External reinforcement of varicose veins with PTFE prosthesis in infrainguinal bypass surgery -- clinical results.
OBJECTIVE Segmental varicose degeneration of the autogenous greater saphenous vein may limit its use in infrainguinal bypass surgery. Wrapping a PTFE prosthesis around dilated veins has emerged as an option to create externally reinforced vein bypasses. Results regarding graft patency and limb salvage were analyzed. METHODS Between September 1995 and January 2001, 35 infrainguinal bypass operations in 33 patients were performed with greater saphenous veins exhibiting segmental varicose dilatation. Grafts were followed by duplex scan and retrospective analysis of graft patency and limb salvage was performed. RESULTS One bypass prompted successful revision for early occlusion. Four bypasses r…
Autogenous Reconstruction of Infected Arterial Prosthetic Grafts Utilizing the Superficial Femoral Vein1
BACKGROUND Prosthetic infection after reconstructive vascular surgery is a most serious complication, associated with high mortality and amputation rates. Following excision of the infected graft, several methods of reconstruction are available. We present here our experience with autogenous reconstruction of infected prosthetic arterial grafts using the superficial femoral vein (SFV). METHODS From November 1995 to December 1999, we used the SFV in seven patients (mean age 70 years) for reconstruction of an infected aortobifemoral (n = 2), aortoiliac (n = 1), femorofemoral bypass (n = 1), femorotibial (n = 2) and carotid crossover bypass (n = 1). Treatment encompassed complete prosthetic ex…
Sequential Femorodistal Composite Bypass with Second Generation Glutaraldehyde Stabilized Human Umbilical Vein (HUV)
Abstract Objective To evaluate the performance of sequential composite bypasses with second generation glutaraldehyde stabilized human umbilical vein (HUV) and autologous vein. Design Retrospective study of consecutive patients, in a single centre. Patients From January 1998 to December 2003, 54 femoro-distal HUV-autologous vein sequential composite bypasses were constructed in 52 patients with critical leg ischemia and absence of sufficient length of autologous vein. Methods All infra-inguinal bypass operations were registered in a computerized database and prospectively followed. Bypasses using sequential HUV-composite technique were reviewed for graft patency, limb salvage and patient su…
Human neutrophil elastase induces endothelial cell apoptosis by activating the PERK‐CHOP branch of the unfolded protein response
Human neutrophil elastase impacts on atherosclerotic plaque stability by inducing apoptosis in endothelial cells. Our aim was to investigate the proapoptotic mechanism of elastase on endothelial cells and to evaluate the presence of elastase in human plaque material. Human endothelial cells were treated with purified human neutrophil elastase. Apoptosis was assayed by capsase-3/7 activation, TUNEL, and sub-G1 assay. Activation of unfolded protein response (UPR) effector molecules binding Ig protein, soluble X-binding protein-1, protein kinase RNA-like ER kinase (PERK), and C/EBP-homologous protein (CHOP) was analyzed by RT-PCR, immunocytochemistry, and Western blot. Genetic silencing of CHO…
Adaptive suppression of the ATF4–CHOP branch of the unfolded protein response by toll-like receptor signalling
The endoplasmic reticulum (ER) unfolded protein response (UPR) restores equilibrium to the ER, but prolonged expression of the UPR effector CHOP (GADD153) is cytotoxic. We found that CHOP expression induced by ER stress was suppressed by prior engagement of toll-like receptor (TLR) 3 or 4 through a TRIF-dependent pathway. TLR engagement did not suppress phosphorylation of PERK or eIF-2alpha, which are upstream of CHOP, but phospho-eIF-2alpha failed to promote translation of the CHOP activator ATF4. In mice subjected to systemic ER stress, pretreatment with low dose lipopolysaccharide (LPS), a TLR4 ligand, suppressed CHOP expression and apoptosis in splenic macrophages, renal tubule cells an…
Outcomes of complex femorodistal sequential autologous vein and biologic prosthesis composite bypass grafts
Objective Femorodistal autologous vein bypass proves to be the preferred surgical therapy for long arterial occlusions and provides excellent early and long-term results in critical lower limb ischemia. Whenever vein length was insufficient and two distal outflow arteries were present, a sequential composite bypass configuration was chosen with human umbilical vein (HUV) or ovine collagen prosthesis (Omniflow II; Bio Nova International Pty Ltd, North Melbourne, Australia) as the proximal prosthetic part of the bypass. Single-center experience with this technique regarding limb salvage, graft function, secondary reinterventions, and biodegeneration is presented. Methods Between January 1998 …
Leukocyte–platelet aggregates—a phenotypic characterization of different stages of peripheral arterial disease
The formation of monocyte-platelet aggregates and neutrophil-platelet aggregates (MPA and NPA, respectively) is influenced by inflammation, but also might contribute to an exacerbation of inflammatory responses in atherosclerotic plaque. The purpose of this study was to analyze MPA and NPA proportions in regard to different stages of peripheral arterial disease (PAD). Forty-five patients with intermittent claudication (IC) (3 groups: Rutherford (R)-1, R-2, and R-3; each n = 15), 20 patients with critical limb ischemia (CLI) (Rutherford 5 (40%) and 6 (60%)), and 20 healthy controls were studied. Analyses of monocyte (Mon) subpopulations (CD14++CD16- (classical) Mon1, CD14++CD16+ (intermediat…
CAMKIIγ suppresses an efferocytosis pathway in macrophages and promotes atherosclerotic plaque necrosis
Atherosclerosis is the underlying etiology of cardiovascular disease, the leading cause of death worldwide. Atherosclerosis is a heterogeneous disease in which only a small fraction of lesions lead to heart attack, stroke, or sudden cardiac death. A distinct type of plaque containing large necrotic cores with thin fibrous caps often precipitates these acute events. Here, we show that Ca2+/calmodulin-dependent protein kinase gamma (CaMKII gamma) in macrophages plays a major role in the development of necrotic, thin-capped plaques. Macrophages in necrotic and symptomatic atherosclerotic plaques in humans as well as advanced atherosclerotic lesions in mice demonstrated activation of CaMKII. We…
Three-Dimensional Analysis of Component Stability of the Nellix Endovascular Aneurysm Sealing System After Treatment of Infrarenal Abdominal Aortic Aneurysms
Purpose: To assess short-term stability and conformational changes of the Nellix EndoVascular Aneurysm Sealing (EVAS) System using 3-dimensional (3D) analysis. Methods: Postoperative computed tomography (CT) scans obtained at 0, 3, and 12 months in 24 patients (mean age 75±7 years; 22 men) who underwent EVAS between December 2013 and December 2014 for intact abdominal aortic aneurysm (within the instructions for use) were evaluated for stent-graft deviation in multiple planes using dedicated 3D analysis software. In addition, 2D analysis using an anatomically fixed reference landmark was performed to assess craniocaudal migration. Clinical and follow-up data of the patients were recorded a…
Femoropopliteal prosthetic bypass with glutaraldehyde stabilized human umbilical vein (HUV).
Objective Femoropopliteal bypass still is the standard surgical therapy for disabling claudication and critical ischemia. When autologous vein is not suitable synthetic or biological prostheses may be considered. Second generation glutaraldehyde tanned human umbilical vein (HUV) graft was chosen for above and below knee femoropopliteal bypass when autologous vein was not available. A single center experience regarding long-term graft function, secondary reinterventions, and potential biodegeneration of the HUV is presented. Methods Between January 1994 and January 2005, 211 consecutive femoropopliteal bypass operations with HUV (65 above knee and 146 below knee) were performed in 197 patien…
Extracellular Nampt promotes macrophage survival via a nonenzymatic interleukin-6/STAT3 signaling mechanism.
Macrophages play key roles in obesity-associated pathophysiology, including inflammation, atherosclerosis, and cancer, and processes that affect the survival-death balance of macrophages may have an important impact on obesity-related diseases. Adipocytes and other cells secrete a protein called extracellular nicotinamide phosphoribosyltransferase (eNampt; also known as pre-B cell colony enhancing factor or visfatin), and plasma levels of eNampt increase in obesity. Herein we tested the hypothesis that eNampt could promote cell survival in macrophages subjected to endoplasmic reticulum (ER) stress, a process associated with obesity and obesity-associated diseases. We show that eNampt potent…
Endovascular Aneurysm Sealing (EVAS) and Chimney EVAS in the Treatment of Failed Endovascular Aneurysm Repairs
Purpose: To assess the technical success and clinical outcome of reinterventions using the Nellix Endovascular Aneurysm Sealing (EVAS) System to treat complications after endovascular aneurysm repair (EVAR). Methods: Fifteen consecutive patients (mean age 79 years; 14 men) with prior EVAR were treated with EVAS between March 2014 and December 2015 at 2 institutions. The failed prior EVARs included 13 bifurcated endografts, 1 bifurcated graft plus fenestrated cuff, and 1 tube endograft. Endoleaks were the predominant indications: type Ia in 10 and type III in 5 (3 type IIIa and 2 type IIIb). All patients presented with progressive aortic aneurysms (median 7.85-cm diameter; range 6.5–11). Ei…
Endovaskuläre Aneurysmatherapie - Langzeitergebnisse nach 7 Jahren
Hintergrund: Seit der Entwicklung von Stentprothesen und deren kommerzieller Verfugbarkeit 1994 gibt es eine neue, sich zunehmend verbreitende endovaskulare Methode der Aneurysmatherapie.
Selective p38α MAP kinase/MAPK14 inhibition in enzymatically modified LDL-stimulated human monocytes: implications for atherosclerosis.
The first ATP-competitive p38α MAPK/MAPK14 inhibitor with excellent in vivo efficacy and selectivity, skepinone-L, is now available. We investigated the impact of selective p38α MAPK/MAPK14 inhibition on enzymatically modified LDL (eLDL) stimulated human monocytes with its implications for atherosclerosis. Among the different p38 MAPK isoforms, p38α/MAPK14 was the predominantly expressed and activated isoform in isolated human peripheral blood monocytes. Moreover, eLDL colocalized with macrophages positive for p38α MAPK/MAPK14 in human carotid endarterectomy specimens. Using the human leukemia cell line THP-1 and/or primary monocyte-derived macrophages, skepinone-L inhibited eLDL-induced ac…
Initial Experience in the Treatment of Extensive Iliac Artery Aneurysms With the Nellix Aneurysm Sealing System.
Purpose: To assess the feasibility and effectiveness of the Nellix prosthesis in the treatment of common iliac artery aneurysms. Methods: Between May 2013 and June 2015, 230 patients underwent implantation of the Nellix device at 2 institutions. Fifty of these patients (mean age 76 years; 35 men) were identified as having 60 common iliac artery aneurysms (CIAAs) with a median diameter of 4 cm (range 3.5–7). The majority of patients had aortoiliac aneurysms (5, 70%), 10 (20%) had isolated CIAAs, and 5 (10%) had iliac anastomotic aneurysms after aortoiliac bypass. In 20 patients, the iliac aneurysm was the indication for the intervention; in the other 30 patients, the endovascular iliac repa…
Early results of a low-profile stent-graft for thoracic endovascular aortic repair
Purpose To assess outcomes of a low-profile thoracic stent-graft in the treatment of thoracic aortic pathologies. Methods A retrospective analysis of all consecutive patients with aortic thoracic pathologies treated with the RelayPro device in two university hospitals between October 2018 and July 2019. Results 23 patients (65% men; mean age 63.4 ± 15 years) were treated. Pathologies included aortic dissections (n = 10), 5 residual type A (22%) and 5 type B (22%), 6 degenerative aortic aneurysms (26%), 4 penetrating aortic ulcers (17%), and aortic erosion, intramural hematoma and aortic rupture (n = 1 and 4% in each case). Two cases (9%) were emergent and two urgent. Proximal landing was a…
Krurale und pedale Bypasschirurgie bei kritischer Isch�mie und nicht heilenden Fu�l�sionen
Die Ischamie ist der haufigste Grund fur nicht heilende Lasionen an den Fusen. Mit der weltweiten Zunahme vaskularer Erkrankungen und insbesondere des diabetischen Fussyndroms steigt auch die Zahl der Patienten, die durch eine Revaskularisation geheilt werden konnen, momentan aber uberwiegend (25.000/Jahr in Deutschland) amputiert werden. In den letzten Jahrzehnten sind in der Gefaschirurgie subtile Methoden entwickelt worden, die auch eine Revaskularisation und Bypassoperationen bei Patienten mit einem distalen Verschlusstyp, der immer haufiger und gerade beim Diabetiker angetroffenen wird, zulassen. Eine besondere Rolle spielt hier der Venenbypass aus V. saphena magna oder alternativen Ve…
Activation of the Proapoptotic Unfolded Protein Response in Plaques of the Human Carotid Artery
Objective To analyze expression of keystone markers of apoptosis and the proapoptotic signaling pathway “unfolded protein response” (UPR) in rupture-prone plaques of the human carotid artery. Methods Plaque specimens were obtained during endarterectomy for high-grade carotid stenosis, and were formalin-fixed. Ten specimens were identified that exhibited criteria of advanced rupture-prone atherosclerotic plaques, and histological and immunohistological analysis of markers of apoptosis (cleaved Caspase-3, TUNEL) and UPR (KDEL, ATF3, CHOP, CHAC-1) was performed. In addition, co-localization of apoptosis and UPR-activation was assessed by double-immunohistochemistry. Results The mean size of th…
MR angiography of the pedal arteries with gadobenate dimeglumine, a contrast agent with increased relaxivity, and comparison with selective intraarterial DSA.
Purpose To compare gadobenate dimeglumine (Gd-BOPTA)–enhanced MR angiography (i.e., contrast-enhanced MRA [CE-MRA]) of the pedal vasculature with selective digital subtraction angiography (DSA) in patients with peripheral arterial occlusive disease (PAOD). Materials and Methods A total of 22 patients with PAOD were prospectively examined at 1.5T. For contrast enhancement, 0.1 mmol/kg body weight of Gd-BOPTA were applied. MRA consisted of dynamic imaging with acquisition of six consecutive data sets. Acquisition time for each data set was 24 seconds, voxel size was 1.0 × 1.0 × 1.3 mm3. A total of 20 out of 22 patient underwent selective DSA, two patients fine-needle DSA. DSA and MRA were per…
Contemporary results with the biosynthetic glutaraldehyde denatured ovine collagen graft (Omniflow II) in femoropopliteal position
Abstract Objective The objective of this study was to analyze the outcome of a contemporary series of femoropopliteal bypass operations with the glutaraldehyde denatured polyester mesh-reinforced ovine collagen prosthesis (OCP; Omniflow II [LeMaitre Vascular, Inc, Burlington, Mass]). The experience of two tertiary centers regarding long-term graft function, secondary reinterventions, and biodegeneration of the OCP prosthesis is presented. Methods Between January 2006 and January 2014, a series of 205 consecutive operations with the OCP in the femoropopliteal position (54 above knee and 151 below knee) were performed in 194 patients in 202 limbs for disabling claudication (72), chronic criti…
Electrospun bioactive mats enriched with Ca-polyphosphate/retinol nanospheres as potential wound dressing
Background While electrospun materials have been frequently used in tissue engineering no wound dressings exist that significantly improved wound healing effectively. Methods We succeeded to fabricate three-dimensional (3D) electrospun poly(D,l-lactide) (PLA) fiber mats into which nanospheres, formed from amorphous calcium polyphosphate (polyP) nanoparticles (NP) and encapsulated retinol (“retinol/aCa-polyP-NS” nanospheres [NS]), had been incorporated. Results Experiments with MC3T3-E1 cells revealed that co-incubation of the cells with Ca-polyP together with retinol (or incubation with retinol/aCa-polyP-NS) resulted in a significant synergistic effect on cell growth compared with particle-…
An imbalance between specialized pro-resolving lipid mediators and pro-inflammatory leukotrienes promotes instability of atherosclerotic plaques
Chronic unresolved inflammation plays a causal role in the development of advanced atherosclerosis, but the mechanisms that prevent resolution in atherosclerosis remain unclear. Here, we use targeted mass spectrometry to identify specialized pro-resolving lipid mediators (SPM) in histologically-defined stable and vulnerable regions of human carotid atherosclerotic plaques. The levels of SPMs, particularly resolvin D1 (RvD1), and the ratio of SPMs to pro-inflammatory leukotriene B4 (LTB4), are significantly decreased in the vulnerable regions. SPMs are also decreased in advanced plaques of fat-fed Ldlr−/− mice. Administration of RvD1 to these mice during plaque progression restores the RvD1:…
Long-term performance of the bovine pericardium patch in conventional carotid endarterectomy.
Objective The aim of the study was to analyze long-term results of carotid endarterectomy (CEA) using bovine pericardium patch. Patients and Methods This study is a retrospective analysis of 274 consecutive cases (173 in CEA group and 101 patients in an internal control group of eversion endarterectomy [EEA]) operated between January 2005 and May 2007. Operations were performed according to standard surgical technique. Primary endpoints of the study were 30-day mortality, ipsilateral neurologic event rate, and high-grade restenosis in the long-term follow-up. Results No statistically significance between both groups was found in terms of gender, age, risk factors, medication (statine, plate…
Complement activation by oxidatively modified low-density lipoproteins
Background Oxidatively modified low-density lipoproteins (LDLs) have been implicated in the pathogenesis of atherosclerosis and are found in human vascular lesions. There is increasing evidence that complement activation may also play a role in atherogenesis. Activated complement proteins have been demonstrated to be present in early atherosclerotic lesions, and lipids isolated from lesions have been shown to activate complement, hence their designation as lesion complement activator (LCA). The question now arose whether oxidized LDLs would also activate complement. Material and methods The complement-activating capacity of a lesion complement activator preparation and of minimally as well …
On the pathogenesis of atherosclerosis: enzymatic transformation of human low density lipoprotein to an atherogenic moiety.
Combined treatment with trypsin, cholesterol esterase, and neuraminidase transforms LDL, but not HDL or VLDL, to particles with properties akin to those of lipid extracted from atherosclerotic lesions. Single or double enzyme modifications, or treatment with phospholipase C, or simple vortexing are ineffective. Triple enzyme treatment disrupts the ordered and uniform structure of LDL particles, and gives rise to the formation of inhomogeneous lipid droplets 10-200 nm in diameter with a pronounced net negative charge, but lacking significant amounts of oxidized lipid. Enzymatically modified LDL (E-LDL), but not oxidatively modified LDL (ox-LDL), is endowed with potent complement-activating c…
Development and evaluation of 3-dimensional printed models of the human tracheobronchial system for training in flexible bronchoscopy.
OBJECTIVES Training and assessment of proper skills in flexible bronchoscopy are major educational goals for cardiothoracic residents. Therefore, we developed 3-dimensional (3D) printed models of the human tracheobronchial system for training and assessment of cardiothoracic residents in flexible bronchoscopy. METHODS Three models of normal (size/shape) human tracheobronchial anatomy were generated using a commercially available 3D printer. Ten residents (inexperienced: Group 1; experienced: Group 2) participated in this study with an experimental setting of initial assessment (Model 1), training (15 min, Model 2) and post-training assessment (Model 3). The time needed for flexible bronchos…