Impact of Revascularization Technique on the Outcomes of Peripheral Graft Revision Procedures.

BACKGROUND: The acute occlusion of a peripheral bypass graft leads to acute limb ischemia (ALI) and threatens the viability of the limb if left untreated. The aim of the present study was to analyze the results of surgical and hybrid revascularization techniques for patients with ALI due to peripheral graft occlusions. METHODS: A retrospective analysis of 102 patients undergoing treatment for ALI due to peripheral graft occlusion between 2002 and 2021 was carried out at a tertiary vascular center. Procedures were classified as surgical when only surgical techniques were used and as hybrid when surgical procedures were combined with endovascular techniques such as balloon or stent angioplasty or thrombolysis. Endpoints were primary and secondary patency and amputation-free survival after 1 and 3 years. RESULTS: Of all patients, 67 met the inclusion criteria, 41 were treated surgically and 26 by hybrid procedures. There were no significant differences in the 30-day patency rate, 30-day amputation rate, and 30-day mortality. The 1- and 3-year primary patency rates were 41.4% and 29.2% overall, respectively; 45% and 32.1% in the surgical group, respectively; and 33.2% and 26.6% in the hybrid group, respectively. The 1- and 3-year secondary patency rates were 54.1% and 35.8% overall, respectively; 52.5% and 34.2% in the surgical group, respectively; and 54.4% and 43.5% in the hybrid group, respectively. The 1- and 3-year amputation-free survival rates were 67.5% and 59.2%, overall, respectively; 67.3% and 67.3% in the surgical group, respectively; and 68.5% and 48.2% in the hybrid group, respectively. There were no significant differences between the surgical and the hybrid groups. CONCLUSIONS: The results of surgical and hybrid procedures after bypass thrombectomy for ALI to eliminate the cause of infrainguinal bypass occlusion are comparable with good midterm results in terms of amputation-free survival. New endovascular techniques and devices need to be established in comparison to the results of these proven surgical revascularization methods.

[Early Thoracic Endografting is Safe in Patients with Uncomplicated Type B Aortic Dissection]. / Die frühelektive endovaskuläre Versorgung der unkomplizierten Aortendissektion Typ B nach Stanford ist sicher.

There are many publications dealing with treatment options for uncomplicated type B aortic dissection (TBAD). Early TEVAR (Thoracic Endovascular Aortic Repair) may improve aortic-specific survival and delay disease progression in the long-term. Especially in patients with uncomplicated TBAD and additional high-risk features, preemptive TEVAR may improve late outcomes.We conducted a retrospective analysis of all patients treated for TBAD in our hospital between February 2017 and September 2021. Comorbidities, intraoperative data, 30-day mortality and postprocedural complications were analysed.During the above-mentioned period, 61 patients (38 males, median age 63 years) with TBAD were treated. Six patients received best medical treatment (BMT). 55 patients were treated by TEVAR and BMT. 11 patients (20%) had complicated TBAD, 12 patients (22%) had uncomplicated TBAD with high-risk features and 32 patients (58%) had uncomplicated TBAD. Technical success was 100%. No patient with uncomplicated TBAD died within the first 30 postoperative days. One patient with uncomplicated TBAD had a stroke after TEVAR. Two reinterventions were performed on day 7 and day 9 after TEVAR.Patients with uncomplicated TBAD could be treated by early TEVAR, with a low rate of perioperative complications. In patients with uncomplicated TEVAR and high-risk features, early TEVAR with BMT should be considered as the treatment of choice.

Impact of chronic kidney disease on the outcomes of infrapopliteal venous, and heparin-bonded expanded polytetrafluoroethylene bypass surgeries: A retrospective cohort study.

The aim of this study was to analyze the results of infrapopliteal venous and prosthetic bypass surgeries for patients with chronic limb-threatening ischemia (CLTI) and moderate to severe chronic kidney disease (CKD). All consecutive patients undergoing infrapopliteal bypass surgeries at two academic vascular centers between March 2002 and November 2018 were included in this retrospective study. During this timeframe, infrapopliteal grafts were performed for 487 patients. Of these patients, 160 (32.9%; group 1) had normal renal function, 248 (50.9%; group 2) had moderate CKD, and 79 (16.2%; group 3) had severe CKD according to the Kidney Disease Improving Global Outcomes guidelines. After 5 years' follow-up, the primary patency rate was 46.0% and the secondary patency rate was 54.9% without statistical significance noted between the CKD groups. Limb salvage (65.3%, p = 0.024) and long-term survival (19.6%, p < 0.001) were considerably lower in patients with severe CKD. In subgroup analysis, vein grafts had significantly better long-term patency rates compared to prosthetic grafts, regardless of CKD group. However, in patients with severe CKD, patency rates of vein and heparin-bonded expanded polytetrafluoroethylene (HePTFE) grafts were comparable at the 1-year mark. Our study shows that autologous vein grafts remain the first choice for infrapopliteal bypass surgeries in patients with CKD. HePTFE grafts showed good short-term results in patients with severe CKD. Given the short life expectancy of these high-risk patients, prosthetic HePTFE grafts may be reasonable in this population if a suitable vein is absent.

Evaluation of Long-Term Outcomes of Femoropopliteal Bypass Surgery in Patients With Chronic Limb-Threatening Ischemia in an Endovascular Era.

BACKGROUND: To investigate the long-term outcomes of femoropopliteal bypass surgery in patients with chronic limb-threatening ischemia (CLTI) and TransAtlantic Inter-Society Consensus II (TASC II), type D (TASC D) femoropopliteal disease. METHODS: A retrospective analysis was performed for all consecutive patients undergoing above-knee (AK) femoropopliteal bypass surgery at an academic vascular centre between January 2007 and March 2019. Patients with claudication (IC) and patients with CLTI were included. Patency rates and freedom from major adverse limb events (MALE) after 5 years were analysed. RESULTS: In total, 432 femoropopliteal grafts were performed. Indications for surgery were claudication and CLTI in 232 (53.7%) and 200 (46.3%) patients, respectively. Graft material was autologous vein in 186 patients (43.1%), polytetrafluoroethylene (PTFE) in 128 patients (29.6%), and heparin-bonded expanded polytetrafluoroethylene (HePTFE) in 118 patients (27.3%). At the 5-year follow-up, the primary patency rate was 58.1% and 58.3% in patients with CLTI and claudication, respectively. Secondary patency rates were 74.1% and 68.6%, respectively. Freedom from MALE was 64.5% and 61.9%, respectively. Analyses of graft material in the CLTI group showed that, at 5 years, autologous vein grafts had better long-term patency rates than PTFE and HePTFE grafts. At 5 years, the primary and secondary patency rate for autologous vein grafts were 63.2% (P= 0.324) and 83.2% (P = 0.020), respectively. Freedom from MALE was 72.0% with the use of autologous vein grafts, 47.9% using PTFE and, 52.9% using HePTFE, respectively (P= 0.021). CONCLUSIONS: Our study shows that femoropopliteal bypass surgery in patients with TASC D lesions is safe and effective in the long term. Autologous vein grafts remain the first choice for patients with CLTI, also for bypasses in AK position. However, prosthetic grafts in AK the position are an acceptable alternative for revascularisation when the saphenous vein is not available.

Midterm outcome of biosynthetic collagen prosthesis for treating aortic and peripheral prosthetic graft infections.

OBJECTIVES: To report the midterm outcomes of treating prosthetic peripheral and aortic graft infections using a biosynthetic collagen prosthesis in a tertiary vascular center. METHODS: A retrospective analysis of all patients with prosthetic peripheral and aortic graft infections who underwent in situ reconstruction using a biosynthetic collagen prosthesis between March 2015 and November 2020 was conducted. Perioperative and midterm outcomes were analyzed. RESULTS: A biosynthetic collagen prosthesis was used in 19 patients (14 males, median age 66 years) to reconstruct the femoral artery (n = 6), iliac artery (n = 1), and infrarenal aorta (n = 12). All patients were treated for a prosthetic vascular graft infection. The median follow-up period was 26.6 months (range 1-66 months). The 30-day graft failure rate was 15.7% (n = 3), leading to a major amputation in one patient (5.3%). All grafts were occluded aortofemoral reconstructions in patients with occluded superficial femoral artery and were treated by immediate thrombectomy. The 30-day mortality rate was 5.3% (n = 1), and survival after 3 years was 63.2%. The reinfection rate was 5.3% (n = 1). At 13.6 months, the occlusion of a femoral graft was detected in 5.3% (n = 1) and was treated with a new interposition graft. We observed no graft rupture or degeneration during follow-up. CONCLUSIONS: Although results of in situ repair with autologous vein seem to be superior with little or none reinfection and low number of occlusions, biosynthetic collagen prostheses show acceptable midterm outcomes in terms of graft occlusion and mortality after prosthetic peripheral and aortic graft infections. Similar to other xenogenous materials, the reinfection rate is low with this prosthesis. With regard to immediate availability and easy handling, the use of a biosynthetic collagen prosthesis might be favorable compared to other replacement materials while treating prosthetic graft infections.

Short and long-term outcome after common femoral artery hybrid procedure in patients with intermittent claudication and chronic limb threatening ischemia.

Background: This study aimed to evaluate the differences between the outcomes of patients with intermittent claudication (IC) and chronic limb threatening ischemia (CLTI) who underwent a hybrid procedure comprising common femoral artery endarterectomy and endovascular therapy. Patients and methods: This was a retrospective single-center study of all patients with peripheral arterial occlusive disease (PAD) who underwent the hybrid procedure between March 2007 and August 2018. The primary endpoint was primary patency after 7 years. The secondary endpoints were primary-assisted patency, secondary patency, limb salvage, and survival. Results: During the follow-up period, 427 limbs in 409 patients were treated. A total of 267 and 160 patients presented with clinical signs of IC and CLTI, respectively. The 30-day mortality was 1.4% (IC: 0% vs. CLTI: 3.8%, p=0.001). The overall 30-day major amputation rate was 1.6% (IC: 0% vs. CLTI: 4.4, p=0.001). The rates of primary and secondary patency after 7 years were 63% and 94%, respectively, in the IC group and 57% and 88%, respectively, in the CLTI group; the difference was not significant. Limb salvage (94% vs. 82%, p=0.000) and survival (58% vs. 29%, p=0.000) were significantly higher in the IC group. In a multivariate analysis, CLTI was the only risk factor for major amputation. CLTI and single vessel run-off were risk factors for death. Statin therapy was a protective factor. Conclusions: The hybrid procedure provides excellent results as a treatment option for multilevel lesions in patients with PAD. However, patients with CLTI had a shorter long-term survival and lower limb salvage rate.

Treatment of Lymphatic Complications after Common Femoral Artery Endarterectomy.

BACKGROUND: This study analyzes the outcome of lymphatic complications after a standard vascular procedure. METHODS: This is a retrospective study including patients who had a lymphatic complication after endarterectomy and patch of the common femoral artery in our clinic between March 2007 and June 2018. Therapy of choice was selected according to wound situation and amount of lymphatic liquid. If signs of a wound infection occurred, a surgical therapy was performed; in all other cases a nonsurgical treatment (conservative treatment, radiotherapy) was chosen. RESULTS: We performed 977 index operations, a lymphatic complication occurred in 112 cases (11.5%). In 69 cases the lymphatic complication presented as lymphatic fistula (Group 1), in 43 cases as lymphorrhea from the wound (Group 2). Nonsurgical treatment was done in 66 cases (Group 1: 76.8% vs. Group 2: 30.2%; P < 0.000), and a surgical treatment was necessary in 46 cases (Group 1: 23.2% vs. Group 2: 69.8%; P < 0.000). Indication for surgery was Szilagyi 1 infection in 25 cases, Szilagyi 2 infection in 11 cases, and Szilagyi 3 infection in 10 cases. Patients with Szilagyi 1 infections received negative wound pressure therapy (NWPT). A muscle flap in combination with an NWPT was performed in patients with Szilagyi 2 infections. In Szilagyi 3 infections, the patch was replaced; additionally, a muscle flap and an NWPT were performed. The median hospital stay was 13 days in the nonsurgical group and 22.5 days in the surgical group. We had no bleeding complications and no reinfection during follow-up. The median observation period was 23.0 months. Age ≥80 years was associated with an increased risk for lymphatic complications. CONCLUSIONS: The therapy of lymphatic complications should be done in accordance with clinical symptoms. A nonsurgical treatment is often sufficient. However, in cases of a wound infection different surgical treatments are necessary.

Remote iliac artery endarterectomy with selective stent use at the proximal dissection zone in TransAtlantic Inter-Society Consensus C and D lesions.

BACKGROUND: Remote iliac artery endarterectomy (RIAE) is a challenging technique in the treatment of arterial occlusive disease. The impact of proximal transection zone stenting on patency rates is still unclear. METHODS: This is a retrospective analysis of all patients who underwent RIAE in our hospital between March 2007 and October 2017. A stent was used in cases with a dissection flap or a stenosis at the proximal transection zone after RIAE. In all other cases, we did not use a stent. Study end points were patency rates, limb salvage, and survival after 5 years. RESULTS: There were 115 RIAEs performed in 108 patients. All lesions were TransAtlantic Inter-Society Consensus C (61.7%) or D (38.3%) lesions. The median follow-up time was 38.5 months (range, 0-117 months). The indications were claudication in 67.0% and critical limb ischemia in 33.0%. Group 1 (n = 56) included all patients without a stent; group 2 (n = 59) included all patients with stenting of the proximal dissection zone. Risk factors were similar between the groups. The 30-day morbidity and mortality rates between the groups were not significantly different. The primary patency rate was 81.6% (group 1, 76.2%; group 2, 87.6%; P = .286), the primary assisted patency rate was 91.9% (group 1, 94.0%; group 2, 90.0%; P = .512), and the secondary patency rate was 93.8% (group 1, 94.0%; group 2, 91.6%; P = .435) after 5 years. Limb salvage (97.2%; group 1, 100%; group 2, 94.5%; P = .084) and survival time (57.1%; group 1, 66.7%; group 2, 43.5%; P = .170) were also not significantly different between the groups. A restenosis at the transection zone occurred in 14.3% in group 1 and 1.7% in group 2 (P = .013) during follow-up. A newly formed occlusion of the hypogastric artery was seen in 5.2% of patients after RIAE. CONCLUSIONS: RIAE is a safe procedure with excellent patency rates. However, the restenosis rate is higher in cases without stenting.

The Multidimensional Prognostic Index in general practice: One-year follow-up study.

BACKGROUND: Older patients' health problems in general practice (GP) can often not be assigned to a specific disease, requiring a paradigm shift to goal-oriented, personalised care for clinical decision making. PURPOSE: To investigate the predictive value of the comprehensive geriatric assessment (CGA)-based Multidimensional Prognostic Index (MPI) in a GP setting with respect to the main healthcare indicators during the 12 months following initial evaluation. METHODS: One hundred twenty-five consecutive patients aged 70 years and older were enrolled in a GP and followed up to one year. All patients underwent a CGA based on which the MPI was calculated and subdivided into three risk groups (MPI-1, 0-0.33 = low risk, MPI-2, 0.34-0.66 = moderate risk and MPI-3, 0.67-1, severe risk). Grade of Care (GC), hospitalization rate, mortality, nursing home admission, use of home care services, falls, number of general practitioner contacts (GPC), of geriatric resources (GR) and geriatric syndromes (GS) during the 12 months following initial evaluation were collected. RESULTS: The MPI was significantly associated with number of GS (P < .001), GR (P < .001), GC (P < .001) as well as with the average number of GPC per year (mean 10.4, P = .046). Interestingly, the clinical judgement of the general practitioner, in this case knowing his patients for 16 years on average, was associated with adverse outcomes to a similar extent than the prediction offered by the MPI (GP/adverse outcomes and MPI/adverse outcomes P < .001). CONCLUSION: The MPI is strongly associated with adverse outcomes in older GP patients and strongly predicts the number of GPC up to one year after initial evaluation. Considering the feasibility and the strong clinimetric properties of the MPI, its collection should be encouraged as early as possible to disclose risk conditions, implement tailored preventive strategies and improve cost-effectiveness of healthcare resources use.

[Management of Endograft Infection After EVAR and TEVAR - a Case Series and Literature Review]. / Management von Stentprotheseninfektionen nach EVAR und TEVAR ­ Fallserie und Literaturübersicht.

Introduction Endograft infection after EVAR (Endovascular aortic repair) or TEVAR (Thoracic endovascular aortic repair) is a rare but severe complication with high mortality. As the number of patients with endovascular aneurysm repair has increased over the last decade, the number of patients with endograft infection might also have increased. However, no guideline defines the treatment of endograft infection. Diagnosis is difficult and depends on clinical symptoms, radiological imaging and blood cultures. Surgery with graft excision, debridement and revascularisation should be proposed. Several techniques and graft materials are used. Additionally long term antibiotic therapy under close control of inflammation markers is always required. Methods We conducted a retrospective analysis of all patients treated for infected aortic endografts in our hospital between January 2008 and May 2017. Study endpoints were freedom from reinfection, survival and primary patency. An extensive electronic health database search was performed to identify articles reporting endograft infection after EVAR and TEVAR. Results We detected aortic endograft infection in three patients (100% male, median age 77 years). In all cases, infrarenal endovascular aortic aneurysm repair had been performed. The infected stent grafts were removed and anatomical revascularisation performed. One homograft and two xenografts were used as graft material. No patient was treated conservatively. A causative organism was found in 2 of the 3 cases. The patients received antibiotics for 12 weeks. Thirty day mortality was 0%. During follow-up, one patient died from bowel perforation after 2 months and another from lung cancer after 92 months. There were no reinfections. Primary patency of the reconstructions was 100%. Publications report high mortality after conservative therapy of endograft infection. There is evidence for lower mortality in patients who underwent surgery. Conclusions Removal of the infected graft, anatomical revascularisation and antibiotic therapy are important for long term survival after aortic endograft infection. Conservative therapy is only warranted in patients unsuitable for surgical treatment.

Simulating Spatial Microwave Manipulation of Polyatomic Asymmetric-Top Molecules Using a Multi-Level Approach.

A numerical approach that employs a multi-level dressed state method to determine the AC-Stark shifts of molecular rotational energy levels is described. This approach goes beyond the two-level approximation often employed for simpler molecules, such as ammonia and acetonitrile, and is applicable to a variety of molecules. The calculations are used to develop experiments aimed at focusing, guiding, decelerating and trapping neutral, polyatomic, asymmetric-top molecules by using microwave fields. Herein, numerical calculations are performed for acetonitrile and 4-aminobenzonitrile. Based on these results, trajectory simulations are performed to predict the outcome of microwave focusing experiments in the TE1,1,p mode of a cylindrically symmetric microwave resonator. Simulations show that, for such an experimental setup, microwave focusing and guiding of 4-aminobenzonitrile requires starting longitudinal velocities close to, or below, 100 m s-1 , that is, much lower than values obtained with standard molecular beam techniques, such as supersonic expansion. Therefore, alternative beam-generation techniques, for example, buffer-gas-cooled molecular beams, are required to extend microwave manipulation methods to larger and more complex molecules.

High-Resolution Rotational Spectroscopy Study of the Smallest Sugar Dimer: Interplay of Hydrogen Bonds in the Glycolaldehyde Dimer.

Molecular recognition of carbohydrates plays an important role in nature. The aggregation of the smallest sugar, glycolaldehyde, was studied in a conformer-selective manner using high-resolution rotational spectroscopy. Two different dimer structures were observed. The most stable conformer reveals C2 -symmetry by forming two intermolecular hydrogen bonds, giving up the strong intramolecular hydrogen bonds of the monomers and thus showing high hydrogen bond selectivity. By analyzing the spectra of the (13) C and (18) O isotopologues of the dimer in natural abundance, we could precisely determine the heavy backbone structure of the dimer. Comparison to the monomer structure and the complex with water provides insight into intermolecular interactions. Despite hydrogen bonding being the dominant interaction, precise predictions from quantum-chemical calculations highly rely on the consideration of dispersion.

The shape of ibuprofen in the gas phase.

Ibuprofen's pain-relieving properties arise from its ability to physically block the active site of an enzyme, thus making its structural and conformational properties highly interesting. We here present a conformer-selective high-resolution broadband rotational spectroscopy study of gas-phase ibuprofen. The interpretation of the spectroscopic results is supported by quantum-chemical calculations. We identify four low-energy conformers that differ in the structural arrangement of the isobutyl moiety with respect to the remainder of the molecule. While the isobutyl group shows high structural flexibility - resulting in distinct low-energy conformers - the propanoic acid group favors a stable arrangement.

Structure determination of trans-cinnamaldehyde by broadband microwave spectroscopy.

The rotational spectrum of trans-cinnamaldehyde ((E)-3-phenyl-2-propenal, C9H8O) was recorded by chirped-pulse Fourier transform microwave spectroscopy in the frequency range of 2-8.5 GHz. The odourant molecule is the essential component of cinnamon oil and causes the characteristic smell. The rotational signatures of two conformers were observed: s-trans-trans- and s-cis-trans-cinnamaldehyde. The rotational spectra of s-trans-trans-cinnamaldehyde and all of its (13)C-monosubstituted species in natural abundance were assigned and the corresponding carbon backbone structure was determined. The second conformer s-cis-trans-cinnamaldehyde is about 9 kJ mol(-1) higher in energy and could also be identified in the spectrum.

Comparison of venous and HePTFE tibial and peroneal bypasses in critical limb ischemia patients unsuitable for endovascular revascularization.

BACKGROUND: We examined short- and long-term outcomes of tibial and peroneal venous and heparin-bonded expanded polytetrafluoroethylene bypasses in patients with critical limb ischemia who were unsuitable for endovascular revascularization. METHODS: A retrospective analysis was done for all patients who underwent tibial and peroneal bypass surgery in our department between October 2007 and October 2012. Vein was the preferred graft material and used whenever possible. RESULTS: One hundred and ninety-eight crural grafts were included. Indications for the surgery were rest pain (30.3%) or ulcer or gangrene (69.7%). Autologous veins were used in 109 cases (vein group) and heparin-bonded expanded polytetrafluoroethylene grafts were used in 89 cases (heparin-bonded expanded polytetrafluoroethylene group). At three years, primary patency for the vein group was 68.2% versus 34.1% for the heparin-bonded expanded polytetrafluoroethylene group (P = .000) and secondary patency was 69.8% versus 35.5% (P = .001). Limb salvage was 81.8% for the vein group versus 56.5% for the heparin-bonded expanded polytetrafluoroethylene group (P = .000) and survival was 62.8% versus 46.7% (P = .019). CONCLUSIONS: The results of our study show that autologous vein grafts are still first choice for tibial and peroneal bypasses in patients with critical limb ischemia. If no adequate vein is available, heparin-bonded expanded polytetrafluoroethylene bypasses are an acceptable alternative to an otherwise impending major amputation.

The influence of continuous local wound infusion on postoperative pain in patients undergoing transfemoral amputation.

BACKGROUND: This pilot study was set up to examine the effects of a continuous postoperative wound infusion system with a local anaesthetic on perioperative pain and the consumption of analgesics. PATIENTS AND METHODS: We included 42 patients in this prospective observational pilot study. Patients were divided into two groups. One group was treated in accordance with the WHO standard pain management protocol and in addition to that received a continuous local wound infusion treatment (Group 1). Group 2 was treated with analgesics in accordance with the WHO standard pain management protocol, exclusively. RESULTS: The study demonstrated a significantly reduced postoperative VAS score for stump pain in Group 1 for the first 5 days. Furthermore, the intake of opiates was significantly reduced in Group 1 (day 1, Group 1: 42.1 vs. Group 2: 73.5, p = 0.010; day 2, Group 1: 27.7 vs. Group 2: 52.5, p = 0.012; day 3, Group 1: 23.9 vs. Group 2: 53.5, p = 0.002; day 4, Group 1: 15.7 vs. Group 2: 48.3, p = 0.003; day 5, Group 1 13.3 vs. Group 2: 49.9, p = 0.001). There were no significant differences between the two groups, neither in phantom pain intensity at discharge nor postoperative complications and death. CONCLUSIONS: Continuous postoperative wound infusion with a local anaesthetic in combination with a standard pain management protocol can reduce both stump pain and opiate intake in patients who have undergone transfemoral amputation. Phantom pain was not significantly affected.

Retrograde thrombendarterectomy vs. ilio-femoral bypass in unilateral iliac TASC C and D lesions.

BACKGROUND: To compare short and long term results of retrograde Thrombendarterectomy (rTEA) and ilio-femoral Bypass (IFBP) to treat iliac TASC C and D lesions. PATIENTS AND METHODS: Retrospective analysis of 108 patients treated at a single vascular center by either rTEA (n = 42) or IFBP (n = 66) over a period of 4 years. RESULTS: Both methods did not significantly differ in 30-day (rTEA 0 % vs IFBP 2 %) or long-term mortality (rTEA 24 % vs IFBP 30 % at 4 years) with a median follow-up of 46 months. There were no procedure related deaths. Patency was similar for both groups (rTEA 93 % vs IFBP 98 % at 30 days; rTEA 83 % vs 92 % IFBP at 4 years). We could not find a significant difference in limb salvage rates (rTEA 93 % vs IFBP 100 % at 30 days and at 4 years). The incidence of prolonged lymphorrhea was significantly higher in the IFBP group (rTEA 0 % vs IFBP 21 %). In 4 IFBP patients a prosthetic graft infection occurred. CONCLUSIONS: Regarding short and long term results operative procedures as rTEA and IFBP still represent the gold standard in the treatment of TASC C and D lesions of the external iliac artery especially in patients with additional lesions in the common femoral and profundal femoral artery. Taking into account certain anatomical characteristics (heavily calcified lesions, narrow external iliac arteries or very tortuous iliac segments) and individual local conditions (prior vascular procedures involving the femoral bifurcation) the single incision retrograde approach to the EIA with rTEA may have advantages over IFBP, especially concerning postoperative complications like lymphorrhea and graft infection.

Pedal bypass surgery after crural endovascular intervention.

BACKGROUND: Many centers choose endovascular intervention as their first-line treatment for crural occlusions in patients with critical limb ischemia (Rutherford 4-6). However, unsuccessful interventions often result in major amputation. Therefore, pedal bypass surgery should be considered as an alternative first-line treatment. We reviewed the impact of a prior endovascular intervention on the outcome of our patients' pedal bypass procedures. METHODS: A retrospective analysis was conducted for all patients who had undergone pedal bypass surgery in our department from February 2008 to October 2012. We performed 75 pedal bypass operations in 71 patients (male, 54; female, 17; median age, 72 years; range, 29-90 years). In 36 of those cases, patients had undergone a prior infrapopliteal endovascular intervention (PEI group). In 39 cases, patients underwent bypass surgery as first-line treatment because their prior angiography had resulted in either unsuccessful endovascular intervention, or intervention had been deemed 'not feasible' (BSF group). Only autologous vein grafts were used, and no retrograde intervention was done via the pedal arteries. Endpoints of the analysis were primary and secondary patency rates, mortality, and limb salvage at 1 year postoperatively. RESULTS: Overall primary patency at 1 year was 58.3%, and secondary patency was 61.3%. Limb salvage was 76.8% and survival was 80.4%. Graft occlusion within 30 days was 18.7%. Revision in those cases was futile and 78.6% of patients had to undergo major amputation. Primary patency at 1 year was 67.0% in PEI group vs 48.3% in BSF group (P = .409) and secondary patency was 73.5% vs 48.6% (P = .100). Prior endovascular intervention had no significant impact on either limb salvage (82.3% vs 71.6% at 1 year; P = .515) or graft occlusions within 30 days (19.4% vs 17.9%; P = .547). Survival rate at 1 year was 79.5% in PEI group and 81.3% in BSF group (P = .765). Risk factors and indications were similar in both groups. CONCLUSIONS: Crural endovascular intervention does not seem to have a negative impact on the outcome of subsequent pedal bypass surgery. Requirements are avoiding a destruction of the target vessel and opting for timely bypass surgery whenever endovascular treatment does not achieve a sufficient perfusion for wounds to heal. Early graft occlusions are associated with a higher risk for major amputation.

Nuclear quadrupole coupling constants of two chemically distinct nitrogen atoms in 4-aminobenzonitrile.

The rotational spectrum of 4-aminobenzonitrile in the gas phase between 2 and 8.5 GHz is reported. Due to the two chemically distinct nitrogen atoms, the observed transitions showed a rich hyperfine structure. From the determination of the nuclear quadrupole coupling constants, information about the electronic environment of these atoms could be inferred. The results are compared to data for related molecules, especially with respect to the absence of dual fluorescence in 4-aminobenzonitrile. In addition, the two-photon ionization spectrum of this molecule was recorded using a time-of-flight mass spectrometer integrated into the setup. This new experimental apparatus is presented here for the first time.

The Impact of Sarcopenia in the Long-Term Survival of Patients following Complex Endovascular Aortic Surgery for Thoracoabdominal Aortic Aneurysms.

OBJECTIVES: Image-based sarcopenia has been the subject of recent studies, hypothesized as a prognostic factor for patients with thoracoabdominal aortic aneurysms. METHODS AND MATERIALS: We conducted a single-center retrospective analysis of patients who underwent complex endovascular repair for thoracoabdominal aortic aneurysms between 2008 and 2016. CT image assessment was performed and patients were classified as sarcopenic and non-sarcopenic using two stratification methods: skeletal mass index (SMI) and total psoas muscle index (TPMI). According to sex, each patient was defined as sarcopenic if their SMI or TPMI was in the lowest third of the study group. The primary endpoint was impact of sarcopenia on perioperative mortality and long-term survival. Secondary endpoints were perioperative complications. RESULTS: From a total of 155 patients, 135 were eligible for study. Overall, in-hospital mortality was 5.9% (8/135). The 30-day, 1-year, 3-year and 5-year mortality was 10.4% (14/135), 20% (27/135), 28.1% (38/135) and 31.1% (42/135), respectively. There was no difference in the long-term mortality rates between sarcopenic and non-sarcopenic patients regardless of the stratification method used (p = 0.4 for SMI and p = 0.2 for TPMI). According to SMI, 30-day mortality of sarcopenic patients was significantly lower in comparison to non-sarcopenic patients (1/45, 2.2% vs. 13/90, 14.4%, p = 0.028). Based on the total psoas muscle index, sarcopenic patients were at higher risk for development of pulmonary complications in comparison to non-sarcopenic patients postoperatively (p = 0.03). CONCLUSION: Using SMI and TPMI, sarcopenia was not associated with reduced long-term survival in patients undergoing complex endovascular repair for thoracoabdominal aortic aneurysms.