Vascular Response Toward an Absorbable Sirolimus-eluting Polymeric Scaffold for Vascular Application in a Model of Normal Porcine Carotid Arteries.

BACKGROUND: Fully absorbable polymeric scaffolds, as a potential alternative to permanent metallic stents, are entering the clinical field. The aim of this study is to assess the in vivo biocompatibility of a novel Sirolimus-eluting (SIR) absorbable scaffold based on poly(L-lactide) (PLLA) and poly(4-hydroxybutyrate) (P4HB) for interventional application. METHODS: Absorbable PLLA/P4HB scaffolds either loaded with SIR coating or unloaded scaffolds were implanted interventionally into common carotid arteries of 14 female. Bare metal stents (BMS) served as control. Peroral dual anti-platelet therapy was administered throughout the study. Stented common carotid arteries segments were explanted after 4 weeks, and assessed histomorphometrically. RESULTS: The absorbable scaffolds showed a decreased residual lumen area and higher stenosis after 4 weeks (PLLA/P4HB: 6.56 ± 0.41 mm² and 37.56 ± 4.67%; SIR-PLLA/P4HB: 6.90 ± 0.58 mm² and 35.60 ± 3.15%) as compared to BMS (15.29 ± 1.86 mm² and 7.65 ± 2.27%). Incorporation of SIR reduced the significantly higher inflammation of unloaded scaffolds however not to a level compared to bare metal stent (PLLA/P4HB: 1.20 ± 0.19; SIR-PLLA/P4HB: 0.96 ± 0.24; BMS: 0.54 ± 0.12). In contrast, the BMS showed a slightly elevated vascular injury score (0.74 ± 0.15), as compared to the PLLA/P4HB (0.54 ± 0.20) and the SIR-PLLA/P4HB (0.48 ± 0.15) groups. CONCLUSION: In this preclinical model, the new absorbable polymeric (SIR-) scaffolds showed similar technical feasability and safety for vascular application as the permanent metal stents. The higher inflammatory propensity of the polymeric scaffolds was slightly reduced by SIR-coating. A smaller strut thickness of the polymeric scaffolds might have been a positive effect on tissue ingrowth between the struts and needs to be addressed in future work on the stent design.

Donor risk indices in pancreas allocation in the Eurotransplant region.

Pancreas donor selection and recognition are important to cope with increasing organ shortage. We aim to show that the PDRI is more useful than the P-PASS to predict acceptance and should thus be preferred over P-PASS. Eurotransplant donors from 2004 until 2014 were included in this study. PDRI logistical factors were set to reference to purely reflect donor quality (PDRI donor ). PDRI and P-PASS association with allocation outcome was studied using area under the receiver operating characteristic curve (AUROC). Regional differences in donor quality were also investigated. Of the 10 444 pancreata that were reported, 6090 (58.3%) were accepted and 2947 (28.2%) were transplanted. We found that P-PASS was inferior to PDRIdonor in its ability to predict organ reporting, acceptance, and transplantation: AUC 0.63, 0.67 and 0.73 for P-PASS vs. 0.78, 0.79 and 0.84 for PDRIdonor , respectively. Furthermore, there were significant differences in donor quality among different Eurotransplant countries, both in reported donors and in transplanted organs. PDRI is a powerful predictor of allocation outcome and should be preferred over P-PASS. Proper donor selection and recognition, and possibly a more liberal approach toward inferior quality donors, may increase donation and transplant rates.

Hybrid aortic arch repair for complicated type B aortic dissection.

OBJECTIVE: This study analyzed the outcome of a combined endovascular and debranching procedure for hybrid aortic arch repair (HAR) in patients with complicated type B aortic dissection. METHODS: Between February 2006 and August 2012, HAR was performed in 75 consecutive patients, with retrospective analysis of a subgroup of 45 patients who underwent HAR with complicated acute (n = 10), subacute (n = 7), or chronic (n = 28) type B dissection as the underlying disease. Descriptive statistics were computed for continuous and categoric variables. The interval to death or last follow-up was estimated using the Kaplan-Meier method. RESULTS: The patients were a mean age of 59.9 ± 10.7 years (median, 59.2; range, 35-78 years). Complete supra-aortic debranching was performed in six (13%) in zone 0 (procedure time, 200 minutes; range, 185-365 minutes) and partial debranching in 39 (87%), comprising 16 (36%) in zone 1 (procedure time, 120 minutes; range, 75-250 minutes) and 23 (51%) in zone 2 (procedure time, 91 minutes; range, 70-210 minutes). Technical success was achieved in 86.7% (39 of 45). Thirty-day mortality was 4.4% (two of 45), with an in-hospital mortality of 11.1% (five of 45) as a result of three additional deaths after days 33, 35, and 111. Comparing HAR for type B dissection after complete debranching in six and partial debranching in 39, the overall in-hospital mortality was 67% (four of six) and 2.6% (one of 39), respectively. After a median follow-up of 20.8 months (range, 0.3-70 months), the overall mortality was 13.3% (six of 45), with Kaplan-Meier survival estimate of 85% at 1 year. Stroke rate was 8.8% (four of 45). Paraplegia developed in one patient (2.2%), with complete recovery after spinal drainage. Cardiac complications occurred in three patients (6.7%), pulmonary complications in 10 (22.2%), and renal insufficiency requiring dialysis developed in five (11%). Retrograde dissection occurred in one patient (2.2%) 14 days after complete debranching and zone 0 thoracic endovascular aortic repair, with fatal outcome. No bypass dysfunction was seen during follow-up. The overall early and late endoleak rates were 27% (12 of 44) and 43% (13 of 30), respectively. Eight patients (18%) required reintervention, with freedom of reintervention in 91% at 1 year and 81% at 2 years. CONCLUSIONS: HAR in zone 1 and 2 appears a viable alternative to conventional aortic arch surgery in patients with complicated type B dissection. Stroke and endoleaks remain complications that need to be addressed. Treatment of type B aortic dissection with complete supra-aortic debranching and thoracic endovascular aortic repair in zone 0, however, is associated with high mortality, which might be reduced by improved technology using branched stent grafts.

Liver transplantation for unresectable hepatocellular carcinoma in normal livers.

BACKGROUND & AIMS: The role of liver transplantation in the treatment of hepatocellular carcinoma in livers without fibrosis/cirrhosis (NC-HCC) is unclear. We aimed to determine selection criteria for liver transplantation in patients with NC-HCC. METHODS: Using the European Liver Transplant Registry, we identified 105 patients who underwent liver transplantation for unresectable NC-HCC. Detailed information about patient, tumor characteristics, and survival was obtained from the transplant centers. Variables associated with survival were identified using univariate and multivariate statistical analyses. RESULTS: Liver transplantation was primary treatment in 62 patients and rescue therapy for intrahepatic recurrences after liver resection in 43. Median number of tumors was 3 (range 1-7) and median tumor size 8 cm (range 0.5-30). One- and 5-year overall and tumor-free survival rates were 84% and 49% and 76% and 43%, respectively. Macrovascular invasion (HR 2.55, 95% CI 1.34 to 4.86), lymph node involvement (HR 2.60, 95% CI 1.28 to 5.28), and time interval between liver resection and transplantation < 12 months (HR 2.12, 95% CI 0.96 to 4.67) were independently associated with survival. Five-year survival in patients without macrovascular invasion or lymph node involvement was 59% (95% CI 47-70%). Tumor size was not associated with survival. CONCLUSIONS: This is the largest reported series of patients transplanted for NC-HCC. Selection of patients without macrovascular invasion or lymph node involvement, or patients ≥ 12months after previous liver resection, can result in 5-year survival rates of 59%. In contrast to HCC in cirrhosis, tumor size is not a predictor of post-transplant survival in NC-HCC.

Arterial microcalcification in atherosclerotic patients with and without chronic kidney disease: a comparative high-resolution scanning X-ray diffraction analysis.

Vascular calcification, albeit heterogeneous in terms of biological and physicochemical properties, has been associated with ageing, lifestyle, diabetes, and chronic kidney disease (CKD). It is unknown whether or not moderately impaired renal function (CKD stages 2-4) affects the physiochemical composition and/or the formation of magnesium-containing tricalcium phosphate ([Ca,Mg](3)[PO(4)](2), whitlockite) in arterial microcalcification. Therefore, a high-resolution scanning X-ray diffraction analysis (European Synchrotron Radiation Facility, Grenoble, France) utilizing histological sections of paraffin-embedded arterial specimens derived from atherosclerotic patients with normal renal function (n = 15) and CKD (stages 2-4, n = 13) was performed. This approach allowed us to spatially assess the contribution of calcium phosphate (apatite) and whitlockite to arterial microcalcification. Per group, the number of samples (13 vs. 12) with sufficient signal intensity and total lengths of regions (201 vs. 232 µm) giving rise to diffractograms ("informative regions") were comparable. Summarizing all informative regions per group into one composite sample revealed calcium phosphate/apatite as the leading mineral phase in CKD patients, whereas in patients with normal renal function the relative contribution of whitlockite and calcium phosphate/apatite was on the same order of magnitude (CKD, calcium phosphate/apatite 157 µm, whitlockite 38.7 µm; non-CKD, calcium phosphate/apatite 79.0 µm, whitlockite 94.1 µm; each p < 0.05). Our results, although based on a limited number of samples, indicate that chronic impairment of renal function affects local magnesium homeostasis and thus contributes to the physicochemical composition of microcalcification in atherosclerotic patients.

Pharmacokinetics and penetration of moxifloxacin into infected diabetic foot tissue in a large diabetic patient cohort.

OBJECTIVES: Physiological changes occurring in patients with diabetes may affect the pharmacokinetics and penetration of antimicrobial agents into peripheral tissue. We examined the pharmacokinetics and the penetration of moxifloxacin into perinecrotic tissue of diabetic foot lesions in patients with diabetic foot infections (DFI). PATIENTS AND METHODS: Adult patients suffering from type 2 diabetes mellitus and hospitalized for DFI (Texas classification of at least B2) were treated with 400 mg moxifloxacin intravenously (IV) or orally (PO) once daily. The pharmacokinetics of moxifloxacin and its concentration 3 h after administration in samples of perinecrotic tissue resected from infected diabetic foot wounds were determined at steady state (days 4-8). RESULTS: A total of 53 patients with diabetes mellitus type 2 (mean age 69.4 ± 10.8 years) were included in the study, of whom 28 received PO and 25 IV moxifloxacin therapy for a median of 8 days. In the PO and IV subgroups, the mean maximum observed plasma concentration (C (max)) in plasma was 2.69 and 4.77 mg/l at a median of 2 [time to reach C (max) (T (max)) range 1.0-8.0 h] and 1 h after administration, respectively. A mean area under the plasma concentration-time curve from time 0 until the last quantifiable plasma concentration (AUC(0-24 h)) of 29.36 mg h/l (PO) and 27.09 mg h/l (IV) was achieved. Mean moxifloxacin concentrations in perinecrotic tissue of infected diabetic foot wounds following PO or IV administration were 1.79 ± 0.82 and 2.20 ± 1.54 µg/g, thus exceeding the MIC(90) (minimum inhibitory concentration required to inhibit growth of 90% of organisms) for Staphylococcus aureus (0.25 mg/l) by seven- and eightfold and the MIC(90) for Escherichia coli (0.06 mg/l) by 29-fold and 36-fold, respectively. The mean tissue-to-plasma ratios of moxifloxacin concentration 3 h after administration were 1.01 ± 0.57 (PO) and 1.09 ± 0.69 (IV). Significant differences between the routes of administration were observed for T (max) and C (max) (P < 0.01), but not for other clinically relevant parameters (AUC(0-24); moxifloxacin DFI tissue concentration). CONCLUSIONS: The plasma concentration-time curve of moxifloxacin in diabetic patients is similar to that of healthy volunteers. We also observed a good penetration of moxifloxacin into inflamed DFI tissue which taken together with the possibility of sequential IV/PO therapy suggest that moxifloxacin 400 mg once daily is a therapeutic option in the treatment of DFI caused by susceptible organisms.

Laparoscopic treatment of renal artery entrapment.

Renal artery entrapment by the diaphragmatic crus is a very infrequent cause of renovascular hypertension. We present the case of a young man who was assigned to our hospital with arterial hypertension and stenosis of the left renal artery. Extrinsic compression was diagnosed by duplex ultrasound and magnetic resonance angiography. We performed laparoscopic decompression using the transperitoneal retrorenal approach. Antihypertensive medication could be stopped thereafter and duplex ultrasound revealed a normal blood flow to the left renal artery. We therefore propose laparoscopic treatment of left renal artery entrapment as a minimally-invasive alternative to open surgery.

Fibroblast growth factor (FGF)-23 and fetuin-A in calcified carotid atheroma.

AIMS: Human atheroma calcification occurs secondary to repetitive injury/remodelling of the vessel wall and might be initiated by adherence of mineral-loaded fetuin-A whether or not professional matrix mineralizing cells are present. The aim was to investigate the contribution of fibroblast growth factor (FGF)-23 to ectopic mineralization. METHODS AND RESULTS: Serial sections of formalin-fixed paraffin-embedded human carotid atheroma (n = 54) were investigated with respect to (i) size and distribution of calcific deposits, (ii) indicators of chondrogenic/osteogenic transformation, and (iii) expression of fetuin-A and FGF-23. All specimens were calcified and SOX-9, collagen type II, cathepsin-K, fetuin-A and FGF-23 expression was seen in 46, 53, 53, 54 and 48 specimens, respectively. The intracellular detection of FGF-23 (45/48) indicates local synthesis. Whereas fetuin-A expression was seen also within areas of vascular smooth muscle actin-positive cells adjacent to calcific deposits, FGF-23 expression was apparently restricted to the mineralization-prone areas. Both local expression and FGF-23 serum concentrations were significantly associated with the degree of atheroma calcification. CONCLUSIONS: Besides the induction of bone islets and subsequent mineral deposition, severe remodelling of the vessel wall is sufficient to create a mineralizable fetuin-A-attracting microenvironment. FGF-23 might contribute to the formation of proper mineral, i.e. control local phosphate concentration.

Center Volume Is Associated With Outcome After Pancreas Transplantation Within the Eurotransplant Region.

BACKGROUND: Outcome after surgery depends on several factors, among these, the annual volume-outcome relationship. This might also be the case in a highly complex field as pancreas transplantation. No study has investigated this relationship in a European setting. METHODS: All consecutive pancreas transplantations from January 2008 until December 2013 were included. Donor-, recipient-, and transplant-related factors were analyzed for their association with patient and graft survivals. Centers were classified in equally sized groups as being low volume (<5 transplantations on average each year in the 5 preceding years), medium volume (5-13/year), or high volume (≥13/year). RESULTS: In the study period, 1276 pancreas transplantations were included. Unadjusted 1-year patient survival was associated with center volume and was best in high volume centers, compared with medium and low volume: 96.5%, 94% and 92.3%, respectively (P = 0.017). Pancreas donor risk index (PDRI) was highest in high volume centers: 1.38 versus 1.21 in medium and 1.25 in low volume centers (P < 0.001). Pancreas graft survival at 1 year did not differ significantly between volume categories: 86%, 83.2%, and 81.6%, respectively (P = 0.114). After multivariate Cox-regression analysis, higher PDRI (hazard ratio [HR], 1.60; P < 0.001), retransplantation (HR, 1.91; P = 0.002), and higher recipient body mass index (HR, 1.04; P = 0.024) were risk factors for pancreas graft failure. High center volume was protective for graft failure (HR, 0.70; P = 0.037) compared with low center volume. CONCLUSION: Patient and graft survival after pancreas transplantation are superior in higher volume centers. High volume centers have good results, even though they transplant organs with the highest PDRI.

INvestigation of STEnt grafts in patients with type B Aortic Dissection: design of the INSTEAD trial--a prospective, multicenter, European randomized trial.

PURPOSE: This study describes the design of an ongoing randomized trial initiated to compare the 2-year outcome of uncomplicated type B aortic dissection when treated by endovascular implantation of a Medtronic Talent stent graft adjunctive to best medical treatment versus best medical treatment alone. METHODS: Patients older than 18 years with type B aortic dissection as diagnosed by computed tomography or magnetic resonance angiography are randomized to either a thoracic aortic endoprosthesis and antihypertensive treatment, called "stent grafting," or a tailored antihypertensive treatment, called "medical treatment." Only patients in a clinically stable condition and without spontaneous thrombosis of the false lumen after 14 days of the index dissection are considered eligible for study inclusion. RESULTS: Primary outcome measure is all-cause mortality. Secondary outcome variables include conversion to stent and/or surgery, induced thrombosis of the false lumen, cardiovascular morbidity, aortic expansion (>5 mm/y of maximum diameter including true and false lumina), quality of life, and length of intensive care unit and hospital stay. The study design calls for 136 patients to be randomized and monitored for 24 months. CONCLUSIONS: The INSTEAD trial is the first randomized trial investigating the role of endoluminal treatment of uncomplicated type B aortic dissection. By the end of December 2004, 125 patients were randomized, accounting for 92% of the target. Final results of the INSTEAD trial should be available in 2006.

Long-term follow-up of 78 simultaneous pancreas-kidney transplants at a single-center institution in Europe.

BACKGROUND: The objective of this study was to determine the long-term results after simultaneous pancreas-kidney transplantation (SPK) at a single-center institution in Europe. PATIENTS AND METHODS: Seventy-eight consecutive patients with insulin-dependent diabetes mellitus and end-stage nephropathy were followed for a median of 7 years after SPK. Immunosuppressive protocol consisted of cyclosporine A, azathioprine, prednisone, and antithymocyte globulin. Multivariate Cox proportional hazard model was used to investigate the impact of different putative risk factors on long-term patient survival. Health-related quality of life was assessed by a validated questionnaire (SF-36). RESULTS: Patient survival at 5 and 10 years was 81% and 67%, respectively. Pancreas function rate was 73% and 60% and kidney function 67% and 44%, respectively. In multivariate analysis, preexisting myocardial infarction (relative risk [RR] 5.1, 95% confidence interval [CI] 1.5-16.6) and amputation (RR 3.7, 95% CI 1.1-12.9) were strongly associated with a diminished long-term patient survival. Analysis of patients with long-term functioning pancreas and kidney grafts revealed excellent results for quality of life posttransplant that were comparable with average scores of the normal German population. CONCLUSIONS: This series representing the largest experience with long-term follow-up in Europe confirms an excellent long-term survival and an exceptional quality of life after SPK.

Anti-oxidant ebselen delays microvascular thrombus formation in the rat cremaster muscle by inhibiting platelet P-selectin expression.

Ebselen, a seleno-organic compound showing glutathione per-oxidase-like activity, has potent anti-inflammatory and anti-oxidant effects. Since selenium deficiency is thought to be associated with an increased incidence of vascular thrombosis, we studied the effect of ebselen on blood cell aggregate formation and vessel occlusion in vivo. In individual microvessels of rat cremaster muscle preparations, photochemically induced thrombus formation was analyzed in detail using intravital fluorescence microscopy. In ebselen-pretreated animals (30 mg/kg ip), venular thrombus formation was significantly delayed (50% vessel occlusion: 535+/-34 s; initial stasis: 872+/-82 s; complete occlusion: 908+/-87 s) as compared to vehicle-treated controls (416+/-42; 612+/-49; 647+/-51). Moreover, ebselen significantly prolonged the kinetics of arteriolar thrombus formation and even completely prevented blood cell aggregate and thrombus formation in 88.9% of all arterioles studied (p<0.05 vs controls: 37.5%). Anti-thrombotic properties of ebselen could also be observed in a model of ferric chloride-induced microvascular thrombosis, with a low dose (5 mg/kg ip) being as effective as a high dose pretreatment (30 mg/kg ip). As assessed by flow cytometry of platelet P-selectin immunfluorescence, whole blood isolated from ebselen-treated animals revealed a significantly lower fraction of P-selectin expressing platelets when compared with that of DMSO-treated controls. In addition, oxidant stress-induced upregulation of P-selectin on isolated platelets was found dose-dependently inhibited by increasing concentrations of ebselen (10-100 micro M). Moreover, ebselen dose-dependently inhibited H(2)O(2)-induced platelet-leukocyte aggregate formation in whole blood in vitro, suggesting that the anti-thrombotic effect of ebselen is achieved by attenuation of P-selectin dependent platelet-leukocyte aggregation. Thus, ebselen represents preventive and therapeutic value for disorders with increased risk for oxidant stress-associated thrombotic events.

Delayed gastric emptying after pylorus-preserving pancreatoduodenectomy is strongly related to other postoperative complications.

Patients undergoing pylorus-preserving pancreatoduodenenectomy (PPPD) have a risk of up to 50% for developing delayed gastric emptying (DGE) in the early postoperative course. From 1994 to August 2002, a total of 204 patients underwent PPPD for pancreatic or periampullary cancer (50%), chronic pancreatitis (42%), and other indications (8%). Retrocolic end-to-side duodenojejunostomy was performed below the mesocolon. DGE was defined by the inability to tolerate a regular diet after day 10 (DGE10) or day 14 (DGE14) postoperatively, as well as the need for a nasogastric tube at or beyond day 10 (DGE10GT). Postoperative morbidity was 38%, 30-day mortality was 2.9%, and median postoperative length of stay was 15 days. DGE occurred in 14.7% (DGE10), 5.9% (DGE14), and 6.4% (DGE10GT), respectively. After further exclusion of 21 patients (10.3%) with major complications and no possible oral intake (because of death, reoperation, or mechanical ventilation), the frequencies of DGE10, DGE14, and DGE10GT in the remaining group of 183 patients were 9%, 2%, and 2%, respectively. Multivariate analysis revealed postoperative complications (P<0.001), the presence of portalvenous hypertension (P<0.01), and tumors as indications for surgery (P<0.01) as independent risk factors for DGE10. The overall incidence of DGE was low after PPPD. In those patients experiencing DGE, however, other postoperative complications were the most important factor associated with its occurrence.

Risk factors for complications after pancreatic head resection.

BACKGROUND: Postoperative morbidity is high after pancreatic head resections. Data about risk factors are controversial. The aim of this study was to evaluate risk factors for complications after pancreatic head resection and to assess whether the complication rate changed during the study period. METHODS: Data of 301 patients undergoing pancreatic head resection were recorded prospectively. Risk factors were assessed by multivariate analysis. The first and second part of the study period were compared. RESULTS: Mortality was 3%. Overall and surgery-related complications occurred in 42% and 28%, respectively. Independent risk factors for postoperative morbidity were impaired renal function (odds ratio [OR] 2.7), absence of preoperative biliary drainage (OR 1.9), and resection of other organs (OR 3.2). Complication rate, duration of surgery, amount of blood transfused, and length of hospital stay decreased during the study period. CONCLUSIONS: Increasing hospital experience decreased complication rates. Patients with risk factors should be considered for transferal to specialized centers.

[Routine use of Brener shunt during carotid endarterectomy].

OBJECTIVE: To evaluate the routine use of Brener shunt during carotid endarterectomy (CEA). METHODS: A prospective audit of the results of 58 consecutive CEA was performed, with routine use of Brener shunt in surgical hospital, Rostock university in Germany. Intraoperative and postoperative complications of CEA were reviewed. RESULTS: In this study, the successful rate of insertion of shunt was 100%. The perioperative stroke/death rate at 30 days was 0, but the TIA rate was 2 cases (3.5%), which was related with previous stroke and contralateral internal carotid occlusion. 2 cases (3.5%) had minor operative complications. CONCLUSIONS: The routine use of Brener shunt has a less rate of intraoperative and early postoperative neurologic complications during CEA. But experience in a large number of shunting procedure is needed.

Enhanced visualization of biodegradable polymeric vascular scaffolds by incorporation of gold, silver and magnetite nanoparticles.

Due to improved tissue regeneration and the enabling of post-operative minimally invasive interventions in the same vessel segment, biodegradable polymeric scaffolds represent a competitive approach to permanent metallic stents in vascular applications. Despite these advantages some challenges, such as the improvement of the scaffold mechanics and enhancement of scaffold visibility during the implantation procedure, are persisting. Therefore, the scope of our studies was to investigate the potential of gold, silver and magnetite nanoparticles incorporated in a polymeric blend of poly(L-lactide)/poly(4-hydroxybutyrate) for image enhancement in X-ray, magnetic resonance or near-infrared imaging. Their impact on mechanical properties of such modified scaffold materials was also evaluated.

Development of a sirolimus-eluting poly (L-lactide)/poly(4-hydroxybutyrate) absorbable stent for peripheral vascular intervention.

Fully absorbable drug-eluting stent platforms are currently entering the clinical arena for the interventional treatment of coronary artery disease. This new technology also holds potential for application in peripheral vascular settings. Our study reports on the development of a sirolimus- (SIR) eluting absorbable polymer stent made from a blend of poly(l-lactide) and poly(4-hydroxybutyrate) (PLLA/P4HB) for peripheral vascular intervention. Stent prototypes were laser-cut from PLLA/P4HB tubes (I.D.=2.2 mm, t=250 µm), spray-coated with different PLLA/P4HB/SIR solutions, and bench-tested to determine expansion properties, fatigue, trackability and in vitro drug release kinetics. The stent prototypes were expanded with a 5.0 × 20 mm balloon catheter, and exhibited a recoil of 3.6% upon balloon deflation. Stent collapse pressure of 0.4 bar (300 mm Hg) was measured under external pressure load. Sustained scaffolding properties were observed in vitro over 14 weeks of radial fatigue loading (50 ± 25 mm Hg at 1.2 Hz). Trackability was demonstrated in bench tests with an 8 French contralateral introducer sheath. SIR release kinetics were adjusted over a broad range by varying the PLLA/P4HB ratio of the coating matrix. The newly developed absorbable SIR-eluting PLLA/P4HB stent successfully fulfilled the requirements for peripheral vascular intervention under in vitro conditions.

Superficial arm arteries revisited: Brother and sister with absent radial pulse.

Atypical or superficial courses of arteries of the arm may cause accidents in therapeutic and surgical procedures. Magnetic resonance imaging (MRI) was performed in a female patient and her brother. In addition, 109 cadaver arms were evaluated for superficial arm arteries and relevant vessels were measured with a calliper. In the patient and her brother the distal radial artery was absent in the normal position. Magnetic resonance imaging showed an artery surrounding the distal radius that nourished the dorsal and palmar hand. In addition, a strongly developed median artery was expressed in the patient's brother. It is noteworthy that the female patient suffered from occasional hand pain while her brother did not, which is likely due to the additional expression of a median artery. A high origin of radial artery is found 3.67% of the examined cadavers and can be followed by additional vessels nourishing the biceps brachii or by connections to the brachial artery in the cubital fossa. Superficial ulnar arteries were detected in 1.83% of the cadavers, in both instances accompanied by an absent palmaris longus. Additionally, in one case the fork of the median nerve has moved distally and took its lateral fork from musculocutaneous nerve. In conclusion, family members can bear identical arterial variations as has been observed in the patient's brother. High origin of radial artery and superficial ulnar artery can be accompanied by additional variations concerning vessels, muscles or nerves which have to be considered in the context of invasive and surgical procedures.

A prospective randomized multicenter trial comparing histidine-tryptophane-ketoglutarate versus University of Wisconsin perfusion solution in clinical pancreas transplantation.

We aimed to evaluate early pancreas transplant graft function after histidine-tryptophan-ketoglutarate (HTK) versus University of Wisconsin (UW) perfusion. Prospective randomized multicenter study including 68 pancreas transplantations stratified according to preservation fluid used (27 HTK vs. 41 UW). Primary endpoint was pancreas graft survival at 6 months. Serum alpha-amylase, lipase, C-peptide, HbA1C and exogenous insulin requirement were compared at several time points. Mean pancreas cold ischemia time was 10.8 +/- 3.7 (HTK) vs. 11.8 +/- 3.4 h (UW) (P = 0.247). Simultaneous pancreas-kidney transplantation was performed in 95.6% of the patients, pancreas transplantation alone in 2.9%, and pancreas after kidney transplantation in 1.5%. Six months graft survival was 85.2% (HTK) vs. 90.2% (UW) (P = 0.703). Serum amylase and lipase values did not differ between both the groups during the observation period. C-peptide levels were elevated in both the groups without significant differences at each time point. Higher exogenous insulin requirement early after transplantation in the UW group had resolved at 3 months. Six month patient survival was 96.3% (HTK) vs. 100% (UW) (P = 0.397). With a mean cold ischemia time of 10 h in this study, HTK and UW solutions appear to be equally suitable for perfusion and organ preservation in clinical pancreas transplantation.