0000000000006289

AUTHOR

Christian F. Vahl

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…

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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…

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True-lumen collapse of the ascending aorta in acute type A aortic dissection

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Successful Management of Fulminant Pulmonary Embolism Using a Novel Portable Extracorporeal Life Support System

A 46-year-old man presented to the emergency room with pain in his left leg, dyspnea, and general cyanosis. During examination he collapsed and required resuscitation. Under suspicion of pulmonary embolism, a new portable "click 'n run" extracorporeal life support system (LIFEBRIDGE-B(2)T [Medizintechnik AG, Ampfing, Germany]) was implanted by the femoral vessels under resuscitation within 15 minutes of presentation. The patient was stabilized, despite severe decompensation (pH, 6.8), and could be transferred for a computed tomographic scan, which confirmed massive pulmonary embolism. Still connected to the life support system, the patient was transferred to the operating room. After a pulm…

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Modified Silk with Cell-Adhesive and Non-Thrombogenic Properties as a Tissue Engineering Substrate

IntroductionReplacement of damaged tissue is nowadays an aim of tissue engineering. This technique involves the use of porous or fibrous structures – the so-called scaffolds – that support the colonization with the desired cell type and which are degraded after fulfilling their temporary supporting function. Basic requirements for the prevailing materials used in this field are nontoxicity, low immunogenicity and cell-adhesiveness. Furthermore blood-contacting devices should exhibit low thrombogenicity.The biopolymer silk, mainly consisiting of the protein silk fibroin, matches some of these criteria but bare silk does not facilitate cellular adhesion and growth and unfortunately the materi…

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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…

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A minimally invasive approach for aortobifemoral bypass procedure

Surgical aortobifemoral bypass procedure for aortoiliac occlusive disease remains the gold standard treatment despite rapidly expanding range of indications for endovascular repair. Besides several disadvantages such as dysparaesthesias, hernias, and unpleasant outcome, transperitoneal exposure of the aorta is also associated with operative autonomic nerve injury. In five male patients, infrarenal aorta was exposed through a small (8 cm) supraumbilical midline incision. Incision of the posterior peritoneum above the infrarenal aorta was limited to 3 cm. A 1 cm infraumbilical incision allowed transperitoneal placement of the distal aortic clamp outside of the operative field. Four centimeter…

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Liver transplantation and combined liver-heart transplantation in patients with familial amyloid polyneuropathy: A single-center experience

Liver transplantation (LT) is the only curative option for patients with familial amyloid polyneuropathy (FAP) at present. Twenty patients with FAP underwent LT between May 1998 and June 2007. Transthyretin mutations included predominantly the Val30Met mutation but also 10 other mutations. Seven patients received a pacemaker prior to LT, and because of impairment of mechanical cardiac function, 4 combined heart-liver transplants were performed, 1 simultaneously and 3 sequentially. The first patient, who underwent simultaneous transplantation, died. Seven patients died after LT, with 5 dying within the first year after transplantation. The causes of death were cardiac complications (4 patien…

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Lobar lung resection in elderly patients with non-small cell lung carcinoma: impact of cardiac comorbidity on surgical outcome.

Principles The aim of this study was to evaluate the impact of cardiac comorbidity on the perioperative morbidity and mortality after lobar lung resection for lung cancer in patients aged 70 years and older. Methods The medical records of all 68 patients ≥70 years, who underwent lobar lung resection for non-small cell lung cancer (NSCLC) from 2003 to 2011 at our department, were reviewed retrospectively. Twenty-two patients with a mean age of 76.3 years had cardiac comorbidities (Group A) including previous cardiac operations in 4 patients, previous myocardial infarction in 5 patients, previous coronary stent insertion in 3 patients, medically treated coronary artery disease in 10 patients …

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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…

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"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...

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Postoperative non-invasive assessment of pulmonary vascular resistance using Doppler echocardiography.

Non-invasive monitoring of pulmonary vascular resistance (PVR) in postoperative cardiac surgery patients might be useful, particularly for management of pulmonary hypertension. For this purpose, we sought to assess Doppler echocardiography in the intensive care setting. In 73 patients, hemodynamics was measured using both, invasive gold standard (pulmonary artery catheter), and non-invasively by Doppler echocardiography. Four Doppler parameters: (1) tricuspid regurgitant velocity/time-velocity-integral of right ventricular outflow tract (TRV/VTI(RVOT)), (2) tricuspid annular systolic velocity (S'), (3) tricuspid annular strain, and (4) tricuspid annular strain rate, were compared with invas…

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Non‐Pharmacologic Multicomponent Interventions Preventing Delirium in Hospitalized People

BACKGROUND/OBJECTIVES Delirium is a common neurobehavioral complication in hospitalized patients with a high prevalence in various clinical settings. Prevention of delirium is critical due to its common occurrence and associated poor outcomes. Our objective was to evaluate the efficacy of multicomponent interventions in preventing incident delirium in hospitalized patients at risk. DESIGN Systematic review and meta-analysis. SETTING Hospital. PARTICIPANTS We included a study if it was a randomized controlled trial and was evaluating effects of coordinated non-pharmacologic multicomponent interventions in the prevention of delirium. MEASUREMENTS We performed a systematic literature search in…

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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…

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Oxidative Inhibition of the Mitochondrial Aldehyde Dehydrogenase Promotes Nitroglycerin Tolerance in Human Blood Vessels

Objectives We tested the hypothesis of whether an inhibition of the nitroglycerin (GTN) bioactivating enzyme mitochondrial aldehyde dehydrogenase (ALDH-2) contributes to GTN tolerance in human blood vessels. Background The hemodynamic effects of GTN are rapidly blunted by the development of tolerance, a phenomenon associated with increased formation of reactive oxygen species (ROS). Recent studies suggest that ROS-induced inhibition of ALDH-2 accounts for tolerance in animal models. Methods Segments of surgically removed arteria mammaria and vena saphena from patients undergoing coronary bypass surgery were used to examine the vascular responsiveness to GTN and the endothelium-dependent vas…

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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 …

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Reevaluation of direct true lumen cannulation in surgery for acute type A aortic dissection.

Background The optimal mode of arterial cannulation in acute type A aortic dissection is controversial. We retrospectively investigated our experience with direct true lumen cannulation as an alternative to standard cannulation procedures. Methods From April 2004 to August 2007, 29 patients (20 men, 9 women; mean age of 63.2 ± 12.6 years) underwent emergency operation for acute type A aortic dissection with direct true lumen cannulation. After venous drainage into the venous reservoir, the ascending aorta was completely transected in the region between the sinotubular junction and innominate artery. After visual and digital identification of the true lumen, the arterial cannula was directly…

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Successful transcatheter aortic valve-in-valve implantation in a patient having a chronic type A aortic dissection

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Mortality in patients with acute aortic dissection type A: analysis of pre- and intraoperative risk factors from the German Registry for Acute Aortic Dissection Type A (GERAADA)

Acute aortic dissection type A (AADA) is an emergency with excessive mortality if surgery is delayed. Knowledge about independent predictors of mortality on surgically treated AADA patients is scarce. Therefore, this study was conducted to identify pre- and intraoperative risk factors for death.Between July 2006 and June 2010, 2137 surgically treated patients with AADA were enrolled in a multicentre, prospective German Registry for Acute Aortic Dissection type A (GERAADA), presenting perioperative status, operative strategies, postoperative outcomes and AADA-related risk factors for death. Multiple logistic regression analysis was performed to identify the influence of different parameters …

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How to do it: direct true lumen cannulation technique of the ascending aorta in acute aortic dissection type A†

In acute aortic dissection type A (AADA), direct true lumen cannulation (DTLC) of the ascending aorta is a fast and safe cannulation site providing antegrade perfusion of the supraaortic and visceral vessels. An Overholt clamp is passed around the ascending aorta to place a Mersilene tape for later securing of the arterial cannula. After draining venous blood into the cardiopulmonary bypass system (CPB), the ascending aorta is transected and the aortic lumen inspected. The true lumen is identified and an arterial cannula inserted directly. Finally, the cannula is secured with the previously placed tape and CPB is initiated. DTLC can be used as arterial cannulation standard technique in oper…

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Survival after Suicidal Transsection of the Left Common Carotid Artery in Octogenarian

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Giant bronchogenic cyst within the aortic wall mimicking symptoms of acute type A aortic dissection.

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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 …

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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…

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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…

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Cell Adhesive and Antifouling Polyvinyl Chloride Surfaces Via Wet Chemical Modification

Polyvinyl chloride (PVC) is one of the most frequently used polymers for the manufacturing of medical devices. Limitations for its usage are based upon unfavorable surface properties of the polymer including its hydrophobicity and lack of functionalities in order to increase its versatility. To address this issue, wet chemical modification of PVC was performed through surface amination using the bifunctional compound ethylene diamine. The reaction was conducted in order to achieve maximum surface amination while leaving the bulk material unaffected. The initial activation step was characterized by means of various methods including contact angle measurements, colorimetric amine quantificati…

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Covalent RGD modification of the inner pore surface of polycaprolactone scaffolds

Scaffold production for tissue engineering was demonstrated by means of a hot compression molding technique and subsequent particulate leaching. The utilization of spherical salt particles as the pore-forming agent ensured complete interconnectivity of the porous structure. This method obviated the use of potentially toxic organic solvents. To overcome the inherent non-cell-adhesive properties of the hydrophobic polymer polycaprolactone (PCL) surface activation with a diamine was performed, followed by the covalent immobilization of the adhesion-promoting RGD-peptide. The wet-chemical approach was performed to guarantee modification throughout the entire scaffold structure. The treatment wa…

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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…

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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…

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Septic cardiomyopathy: evidence for a reduced force-generating capacity of human atrial myocardium in acute infective endocarditis

AbstractBackground:This study analyzes the myocardial force-generating capacity in infective endocarditis (IE) using an experimental model of isolated human atrial myocardium. In vivo, it is difficult to decide whether or not alterations in myocardial contractile behavior are due to secondary effects associated with infection such as an altered heart rate, alterations of preload and afterload resulting from valvular defects, and altered humoral processes. Our in vitro model using isolated human myocardium, in contrast, guarantees exactly defined experimental conditions with respect to preload, afterload, and contraction frequency, thus not only preventing confounding by in vivo determinants…

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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…

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How should I treat a DeBakey type I acute aortic dissection four weeks after transcatheter aortic valve implantation in an old, fragile patient?

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Comparative intention-to-treat analysis of the video-assisted thoracoscopic surgery approach to pulmonary segmentectomy for lung carcinoma

Objectives To compare the video-assisted thoracoscopic surgery (VATS) with the open thoracotomy access to pulmonary segmentectomy by the clinical outcomes and long-term survival in lung carcinoma. Methods Non-randomized comparative intention-to-treat study of prospective institutional registry data and survival data of 100 consecutive patients undergoing segmentectomy. Results Within one decade (2002-12), 100 patients with proven or highly suspected lung carcinoma underwent 100 anatomical sub-lobar pulmonary resections (52 typical and 20 atypical segmentectomies, 28 split-lobe procedures). Fifty-six patients were operated by VATS and 44 by thoracotomy access. Comparison of demographic, medi…

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A Multicenter Experience With a New Fenestrated-Branched Device for Endovascular Repair of Thoracoabdominal Aortic Aneurysms.

To investigate the outcomes of patients who were treated for thoracoabdominal aortic aneurysms (TAAAs) using custom-made fenestrated-branched stent-grafts.A consecutive series of 108 patients (mean age 73.5 years; 73 men) with TAAA were treated with E-xtra Design Engineering customized fenestrated-branched stent-grafts between November 2011 and January 2017. Data on baseline characteristics, procedures, and clinical follow-up were collected from 6 regional European surgical centers for retrospective analysis of endoleaks, reinterventions, and target vessel patency. The median aneurysm diameter was 6.75 cm (range 5.5-13). The distribution of the TAAA according to the modified Crawford classi…

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Increased Lymphangiogenesis and Lymphangiogenic Growth Factor Expression in Perivascular Adipose Tissue of Patients with Coronary Artery Disease

Experimental and human autopsy studies have associated adventitial lymphangiogenesis with atherosclerosis. An analysis of perivascular lymphangiogenesis in patients with coronary artery disease is lacking. Here, we examined lymphangiogenesis and its potential regulators in perivascular adipose tissue (PVAT) surrounding the heart (C-PVAT) and compared it with PVAT of the internal mammary artery (IMA-PVAT). Forty-six patients undergoing coronary artery bypass graft surgery were included. Perioperatively collected C-PVAT and IMA-PVAT were analyzed using histology, immunohistochemistry, real time PCR, and PVAT-conditioned medium using cytokine arrays. C-PVAT exhibited increased PECAM-1 (platele…

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