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We have described a technique to treat iatrogenic coarctation caused by a branched thoracic endovascular aortic repair (TEVAR) procedure with a Palmaz XL stent (Palmaz Genesis; Cordis Corp, a Cardinal Health Company, Milpitas, Calif) and triple kissing balloons. A 42-year-old woman with Marfan syndrome had presented with aneurysmatic dilatation of the aortic arch 10 years after open aortic arch repair. After successful branched TEVAR, a significant coarctation just short of the left common carotid artery was noted with significant pressure gradient between the ascending and descending aorta. Branched TEVAR in previous open aortic arch replacement can result in iatrogenic coarctation that can be successfully treated using a Palmaz XL stent and triple kissing balloons., (© 2021 The Authors.)

Purpose: To report a single-center experience with the use of a custom-made Candy-Plug (CP) for distal false-lumen (FL) occlusion in subacute and chronic aortic dissection (AD)., Materials and Methods: A retrospective single-center analysis was conducted on consecutive patients with subacute and chronic AD who were treated with a custom-made CP for distal FL occlusion using 3 design generations (CP I to CP III) from October 2013 to September 2019., Results: A custom-made CP was used in 57 patients. Of these, 34 patients (29 males, mean age 62±10 years) were treated with a CP I vs 23 patients (16 males, mean age 59±17 years) with CP II/III. Technical success was achieved in 57 (100%) patients. Clinical success was achieved in 54 (95%) patients; 33 (97%) in CP I group vs 21 (91%) patients in CP II/III group, p=0.116. The mean hospital stay was 10±8 days (9±5 days in CP I group vs 13±9 days in CP II/III, p=0.102). The 30-day computed tomography angiography (CTA) confirmed successful CP placement at the intended level in all patients within both groups. Early complete FL occlusion was achieved in 50 (88%) patients; 30 (88%) patients in CP I group vs 20 (87%) in CP II/III group, p=0.894. Follow up CTA was available in 44 (77%) patients. Of these; 30/34 (88%) patients in CP I group with mean follow-up 29±17 months) vs. 14/23 (61%) patients with mean follow-up 14±5 months in CP II/III group. Thoracic aortic remodeling was achieved in 34/44 (77%) patients; 25/30 (83%) patients in CP I group vs 9/14 (64%) patients in CP II/III group, p=0.197. The aneurysm size remained stable in 9/44 (20%) patients; 5/30 (17%) patients in CP I group vs 4/14 (29%) patients in CP II/III group, p=0.741. The thoracic aneurysm increased size was seen in 1/44 (2%) patient. This patient was in CPII/III group., Conclusion: CP technique using custom-made devices is technically feasible with a low mortality and morbidity, and a high rate of aortic remodeling. Both, the original design (CP I) and newer designs with a self-closing central sleeve (CP II and CP III) showed similar excellent outcomes.

Objective: We studied the outcomes of transfemoral access (TFA) vs upper extremity access (UEA) for branched endovascular aortic repair (BEVAR)., Methods: From January 2016 to October 2019, 152 consecutive patients underwent BEVAR under general anesthesia at a single institution. In 2018, an alternative approach to the antegrade branches using TFA compared with conventional UEA was introduced. The cohort was divided into TFA and UEA groups according to the access approach. The end points were technical success, adverse events (including perioperative stroke/transient ischemic attack), access complications, operation time, and radiation exposure., Results: The TFA group included 60 patients (63% male; median age, 71 years; interquartile range [IQR], 65-76 years). The UEA group included 92 patients (67% male; median age, 73 years; IQR, 66-78 years). The number of target vessels (TVs) was similar in both groups (median, 4.0 TVs per procedure; range, 1-7 TVs for both). Technical success was greater in the TFA group (60 of 60 patients; 209 of 209 TVs) than in the UEA group (87 of 92 patients; 334 of 346 TVs; P < .01). The fluoroscopy time (median, 69 minutes; IQR, 48-87 minutes; vs 88 minutes; IQR, 65-104 minutes; P = .39) and contrast agent volume (median, 141 mL; IQR, 123-165 mL; vs median, 130 mL; IQR, 101-157 mL; P = .34) were similar in both groups. The radiation exposure (221 Gy × cm 2 ; IQR, 138-406 Gy × cm 2 ; vs median, 255 Gy × cm 2 ; IQR, 148-425 Gy × cm 2 ; P = .05) was lower and the operation time (median, 300 minutes; IQR, 240-356 minutes; vs median, 364 minutes; IQR, 290-475 minutes; P = .01) was shorter in the TFA group. Brachial access complications (0 of 60 vs 3 of 92 patients) and perioperative strokes/transient ischemic attacks (0 of 60 vs 8 of 92 patients) only occurred in the UEA group (P = .018)., Conclusions: The use of TFA to catheterize antegrade branches was associated with a lower rate of complications in the present study and has become our preferred approach for BEVAR., (Copyright © 2020 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Cardiovascular societies have developed recommendations regarding the management of thoracic aortic diseases. While improvements in treatment have been observed during the past decade in regard to patient selection, thoracic endovascular aortic repair (TEVAR) and associated techniques, and high-volume centralization, the broad expansion of TEVAR has raised considerations about its indications, appropriateness, limitations, and application. The aim of this systematic review was to assess the similarities and differences among current cardiovascular societies' guidelines for the management of thoracic aortic diseases. The MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched from January 2009 to May 2020. The initial search identified 990 articles. After exclusion of duplicate or inappropriate articles, the final analysis included 5 articles from cardiovascular societies published between 2010 and 2020. Selected controversial topics were analyzed, including diagnosis, imaging, spinal cord ischemia prevention, and management of the most important thoracic aortic pathologies. The analysis included data concerning the therapeutic approach in acute and chronic type B aortic dissection, penetrating aortic ulcer, intramural hematoma, thoracic aortic aneurysm, and traumatic aortic injury, as well a discussion of inflammatory aneurysms, aortitis, and genetic syndromes. The review presents consistent and controversial recommendations, as well as "gray zone" issues that need further investigation. There was significant overlap and agreement among the 5 societies regarding the management of thoracic aortic diseases. Especially in dissection and aneurysm management, TEVAR has established its role as the treatment of choice. However, robust evidence is still needed in many aspects of the management of thoracic aortic pathologies.

Purpose: To analyze aortic arch anatomy of patients who were already treated with a 2-inner-branch arch endograft (2-IBAE) in order to assess the anatomical suitability of the supra-aortic arteries as target vessels for a 3-IBAE., Materials and Methods: Three different configurations of the Cook Zenith Arch endograft were designed with distances of 110 mm (model 1), 90 mm (model 2), and 70 mm (model 3) between the orifices of the first and third inner branches. Preoperative measurements of the aortic arch anatomy from 104 consecutive patients treated electively with custom-made 2-IBAEs at 2 European centers between 2014 and 2019 were analyzed. A previously described standard methodology with a planning sheet was used. Data and measurements included the treatment indication for the aortic arch pathology, the type of landing zone, the type of arch, and the inner and outer lengths of the ascending aorta from the sinotubular junction to the innominate artery (IA). Additionally, the diameters and clock positions of the IA, left common carotid artery (LCCA), and left subclavian artery (LSA) were assessed, along with the distances between the IA and the LCCA, the IA and the LSA, and the distal landing zone., Results: Type I was the most common arch configuration (75/104, 72%). The mean clock positions were 12:30±00:28 for the IA, 12:00±00:23 for the LCCA, and 12:15±00:29 for the LSA. The mean diameters were 14.2±2.2 mm for the IA, 8.8±1.8 mm for the LCCA, and 10.5±2 mm for the LSA. The mean distances between the IA and LCCA and between the IA and LSA were 14.7±5.8 mm and 33±9.4 mm, respectively. Model 2 (branch distance 90 mm) had the highest suitability (79%), while models 1 and 3 showed suitability rates of 73% and 68%, respectively. The most frequent exclusion criterion in all models was the diameter of the LSA, followed by the IA to LSA distance., Conclusion: The suitability for a 3-IBAE among patients who had a 2-IBAE implanted is high, favoring a 90-mm distance between the retrograde LSA branch and baseline.

Brain-on-Chip (BoC) biotechnology is emerging as a promising tool for biomedical and pharmaceutical research applied to the neurosciences. At the convergence between lab-on-chip and cell biology, BoC couples in vitro three-dimensional brain-like systems to an engineered microfluidics platform designed to provide an in vivo-like extrinsic microenvironment with the aim of replicating tissue- or organ-level physiological functions. BoC therefore offers the advantage of an in vitro reproduction of brain structures that is more faithful to the native correlate than what is obtained with conventional cell culture techniques. As brain function ultimately results in the generation of electrical signals, electrophysiology techniques are paramount for studying brain activity in health and disease. However, as BoC is still in its infancy, the availability of combined BoC-electrophysiology platforms is still limited. Here, we summarize the available biological substrates for BoC, starting with a historical perspective. We then describe the available tools enabling BoC electrophysiology studies, detailing their fabrication process and technical features, along with their advantages and limitations. We discuss the current and future applications of BoC electrophysiology, also expanding to complementary approaches. We conclude with an evaluation of the potential translational applications and prospective technology developments., Competing Interests: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Objective: Previous studies have showed a potential disadvantage of female patients who underwent abdominal aortic aneurysm (AAA) repair. The current study aims to determine sex-specific perioperative and long-term outcomes using propensity score matched unselected nationwide health insurance claims data., Methods: Insurance claims from a large German fund were used, covering around 8% of the insured German population. Patients who underwent endovascular aortic repair (EVAR) for intact AAA from 1 January 2011 to 30 April 2017 were included in the cohort. A 1:2 female to male propensity score matching was applied to adjust for confounding variables. Perioperative and long-term outcomes after 5 years were determined using matching and regression methods., Results: Among a total of 3736 patients (19.3% females, mean 75 years) undergoing EVAR for intact AAA, we identified 1863 matched patients. Before matching, females were more likely to be previously diagnosed with hypothyroidism, electrolyte disorders, rheumatoid disorders, and depression, while males were more often diabetics. In the matched sample, 23.4% of the females and 25.8% of the males died during a median follow-up of 776 and 792 days, respectively. Perioperatively, females were more likely to exhibit acute limb ischemia (5.3% vs. 3.2%, p = 0.031) and major bleeding (22.0% vs. 15.9%, p = 0.001) before they were discharged to rehabilitation (5.5% vs. 1.5%, p < 0.001) when compared to males. No statistically significant difference in perioperative (odds ratio 1.12, 95% CI 0.54-2.16) or long-term mortality (hazard ratio 0.91, 95% CI 0.76-1.08) was observed between sexes. This was also true regarding aortic reintervention rates after 1 year (2.0% vs. 2.9%) and 5 years (10.9% vs. 8.1%)., Conclusion: The current retrospective matched analysis of insurance claims revealed high early access-related morbidity in females when compared to their male counterparts. Short-term or long-term survival and reintervention outcomes were similar between sexes.

The development of endovascular techniques has improved abdominal aortic aneurysm (AAA) management over the past 2 decades. Different cardiovascular societies worldwide have recommended the endovascular approach as the standard of care in their currently available guidelines. While endovascular treatment has established its role in daily clinical practice, a new debate has arisen regarding the indications, appropriateness, limitations, and role of open surgery. To inform this debate, the MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases were searched from 2010 to May 2020; the systematic search identified 5 articles published between 2011 and 2020 by 4 cardiovascular societies and the National Institute of Health and Care Excellence (NICE). Four debatable domains were assessed and analyzed: diagnostic methods and screening, preoperative management, indications and treatment modalities, and postoperative follow-up and endoleak management. The review addresses controversial proposals as well as widely accepted recommendations and "gray zone" issues that need to be further investigated and analyzed, such as screening in women, medical management, and follow-up imaging. While the recommendations for AAA management have significant overlap and agreement among international cardiovascular societies, the NICE guidelines diverge regarding the role of open repair in aortic disease, recommending conventional surgery in most elective cases.

Purpose: To describe the use of a steerable sheath from a femoral access for antegrade catheterization of the left common carotid artery (LCCA) in an inner-branched arch endograft. Technique: This technique is demonstrated in a patient with residual aortic dissection after replacement of the ascending aorta for acute type A aortic dissection. He presented 4 years later with aneurysmal degeneration of the thoracoabdominal aorta and a proximal tear located in the aortic arch. A 2-stage hybrid approach was devised to treat the patient. An axilloaxillary crossover graft (left to right) with plug occlusion of the innominate artery was performed initially. Later, a dual-branched custom-made device was implanted. To avoid an additional LCCA cutdown for retrograde branch access, an 18-F steerable sheath was used through a percutaneous femoral access. Two wires were delivered within the steerable sheath: the first one was directed into the left subclavian artery to stabilize the sheath position in the ascending aorta; the second wire was used to catheterize the first inner branch and the LCCA to deploy the covered bridging stent. Conclusion: Transfemoral access to catheterize antegrade branches for supra-aortic vessels is feasible using a large steerable sheath in branched endovascular arch repair.

Objective: The purpose of this study was to evaluate the outcome of t-Branch (Cook Medical, Bloomington, Ind) stent graft for the treatment of thoracoabdominal and pararenal aortic aneurysms in patients who had previous infrarenal aortic repair., Methods: A retrospective two-center study was undertaken. All consecutive patients who underwent endovascular repair using t-Branch stent graft after previous infrarenal aortic repair between January 2010 and August 2018 were included. Demographics, past medical history, cardiovascular risk factors, and intraoperative and perioperative details were recorded. Technical success and early (30-day) mortality, morbidity, target vessel patency, and presence of endoleak were analyzed. During the first year of follow-up, survival, freedom from reintervention, and patency rates were recorded., Results: There were 32 patients (mean age, 74 ± 7 years; 81% male) included in the study; 24 (75%) patients had prior open surgical repair, and 8 (25%) patients had undergone standard endovascular aneurysm repair. The index operation was performed 9 ± 5 years earlier, including 10 ± 5 years for open surgical repair and 8 ± 6 years for endovascular aortic repair. The indication was progression of the disease in 26 patients (81%) and type IA endoleak in 6 patients (19%). The total number of target vessels incorporated was 117 arteries (3.8 ± 0.6 target vessels per patient). Eleven patients had only three vessels incorporated; celiac trunk was occluded in three patients, and eight patients had one functioning kidney. Technical success rate was 97% (31/32). There was a single technical failure in one patient who had a type IA endoleak after endovascular repair with suprarenal fixation. The stenotic right renal artery was not catheterized at the initial procedure, and retrograde access was achieved through a right subcostal incision 3 days later with successful completion of the repair. Early mortality rate was 13%, and spinal cord ischemia rate was 22% (7/32); four patients had permanent and three had transient neurologic deficits. Early target vessel patency was 100%, and the rate of any endoleak was 9% (3/32); two patients had type II endoleaks and one patient had type III endoleak. The mean follow-up was 5.4 ± 5.9 months. The cumulative survival rate was 82% and 73% at 6 and 12 months, respectively. The freedom from aorta-related mortality was 92% at 6 and 12 months. The cumulative freedom from reintervention during follow-up was 90% at 6 and 12 months. The overall target vessel patency rate was 100% and 97.5% at 6 and 12 months, respectively., Conclusions: The use of t-Branch off-the-shelf stent graft for the treatment of aortic disease in patients who had previous infrarenal aortic repair appears to be feasible, with acceptable early outcomes in terms of morbidity and mortality., (Copyright © 2020 Society for Vascular Surgery. All rights reserved.)

Purpose: To describe the implantation steps and tips and tricks for the Inner Branch Arch Endograft designed to treat aortic arch aneurysm and chronic type A aortic dissection., Technique: Anatomical suitability criteria should be met in order to use this device. The proximal segment of the graft lands in the ascending aorta distally to the sinotubular junction and the distal segment lands in the descending aorta. The device includes 2 inner branches; the proximal branch is used for a connection to the innominate artery (positioned slightly posterior at 12:30 o'clock), while the second branch is positioned slightly anterior at 11:30 o'clock and is used as a connection to the left common carotid artery. Access, implantation technique, deployment of the device, and catheterization of the branches are described thoroughly., Conclusion: This Inner Branch Arch Endograft is an appealing alternative to treat aortic arch pathology, especially in patients unsuitable for open repair. Nevertheless, complex aortic arch repair is associated with a learning curve. Meticulous preoperative planning and a high level of concentration intraoperatively are mandatory.

Four randomized clinical trials prospectively compared endovascular (EVAR) and open repair (OR) of abdominal aortic aneurysm (AAA): Chronologically these are EVAR 1 (UK), DREAM (Netherlands), OVER (USA) and ACE (France). All of them investigated whether the superior early postoperative outcome of endovascular repair is maintained in the long-term. The longest follow-up data of EVAR 1, with a mean person-years observation (either until death or end of study) of 8 years, clearly question the superiority of EVAR. In this context, open repair of AAA takes on a new significance and the indication for endovascular repair should be critically assessed with regard to the long-term course. Indication for invasive treatment has not changed and should - apart from exceptions - only be given for men with a diameter of 5,5 cm or more. Furthermore, current studies on prophylactic mesh reinforcement after open repair of AAA show that incisional hernias can be safely avoided., Competing Interests: Susanne Honig, Giuseppe Panuccio, Sabine Helena Wipper geben an, keine Interessenkonflikte zu haben. Tilo Kölbel war Co-Autor der ESVS 2019 Clinical Practice Guidelines on the Management of Abdominal Aorto-iliac Artery Aneurysm. Eike Sebastian Debus ist Autor der deutschen S3-Leitlinie zu Screening, Diagnostik, Therapie und Nachsorge des Bauchaortenaneurysmas und war Mitglied des ESVS Guideline Committee zur Erstellung der ESVS 2019 Clinical Practice Guidelines on the Management of Abdominal Aorto-iliac Artery Aneurysm., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: The iliac side branch device (IBD) is a valid method for the treatment of abdominal aorto-iliac aneurysms. However there is still a lack of evidence regarding the optimal length of the bridging stent graft (BSG) since aneurysmal degeneration of the hypogastric artery (HA) is an exclusion criterion. The aim of this study was to analyse the impact of longer BSG compared to the widely used 38mm stent-grafts in terms of reintervention rate and primary patency., Methods: We retrospectively analyzed our prospectively collected database of all patients who underwent an endovascular aneurysm repair using an IBD in our center between April 2005 and May 2015. The used BSGs were divided into 2 groups. In group A, the BSG was ≤38 mm, and group B>38 mm. The primary endpoint was BSG-related events, including stenosis, occlusion or endoleak. Secondary endpoints were technical success, primary patency and 30-day mortality., Results: Two hundred sixty IBDs were implanted in 215 consecutive patients. Ninetyseven (37%) in group A and 163 (63%) in group B. The technical success rate was 100%. The 30-day mortality was 1% (N.=1) and 1.2% (N.=2) respectively for group A and B (P=0.8). The freedom from BSG-related events amounted to 84% at 60 months for the total cohort. The comparison between the two groups shows no significant difference, while a slight favorable trend for group B (75% vs. 91% at 60 months, P=0.081) was observed. No differences were found as to primary patency (96% and 99% at 60 months respectively for group A and B, P=0.237)., Conclusions: The use of longer stent-grafts (>38 mm) seems not to affect the performance of BSG even in the long run, expanding the indication for IBD also for aneurysms of the hypogastric artery.

Purpose: To report a single-center experience with thoracic endovascular aortic repair (TEVAR) for complicated acute type B aortic dissection (cATBAD) comparing patients with vs without end-organ ischemia. Materials and Methods: Between November 2010 and December 2017, 64 patients (mean age 64.8±12.5 years; 49 men) underwent TEVAR for cATBAD. Patients were grouped into 2 cohorts: nonischemic (39, 61%) patients with unrelenting pain, early progressive aortic dilatation, uncontrolled hypertension, or rupture, and ischemic (25, 39%) patients with visceral, renal, lower extremity, or spinal cord hypoperfusion. Results: Mean time from diagnosis to treatment was 7.5 days (range 1-32) in the nonischemic group vs 2.3 days (range 1-14) days in the ischemic group (p=0.007). Fourteen (56%) of 25 ischemic cATBAD patients had stents implanted in the renovascular branch vessels, while 4 (16%) patients had stents implanted in the iliac arteries. When branch vessel cannulation failed, fenestrations were made in the intimal flap to improve perfusion of the involved branch (n=5). In the nonischemic group, 3 arteries were stented owing to atherosclerotic stenosis. Technical success was achieved in 62 (97%) of 64 patients; despite stenting, 2 patients had low renal artery perfusion on final angiography. There were no statistically significant differences in early or late outcomes between the nonischemic vs ischemic cATBAD patients. Six (9%) patients died within 30 days: 2 (5%) in the nonischemic group vs 4 (16%) in the ischemic group. Major complications (1 stroke, 2 cases of paraplegia, 1 retrograde type A dissection, and 1 case of bowel ischemia) occurred only in the nonischemic group. The mean follow-up was 28 months. Late endoleaks were observed in 3 (8%) nonischemic patients and 1 (4%) ischemic patient. Reinterventions were required in 7 (18%) nonischemic patients and 4 (16%) ischemic patients. Conclusion: TEVAR is an effective and safe method of treating cATBAD. Early intervention in ischemic cATBAD may have played a significant role in the lack of significant difference between ischemic and nonischemic cATBAD outcomes. Direct visceral reperfusion through branch vessel stenting during TEVAR may be crucial in achieving good outcomes in ischemic cATBAD.

Purpose: To present the early results of false lumen (FL) occlusion in chronic aortic dissection using the Candy-Plug generation II (CP II), which has a self-closing fabric channel that obviates the need for separate occlusion of its center. Materials and Methods: Fourteen consecutive patients (mean age 60±11 years; 10 men) with persistent FL backflow and aneurysm formation at the thoracic segment in chronic aortic dissection underwent thoracic endovascular aortic repair (TEVAR) with FL occlusion using the refined CP II. Primary endpoints were technical success (successful deployment) and clinical success (no FL backflow at the CP II level). Secondary endpoints included 30-day mortality and morbidity and aortic remodeling during follow-up. Results: Technical success was 100%. One patient required additional intraprocedural FL embolization at the CP II level due to persistent FL backflow on final angiography (clinical success 93%), though there was no flow through the CP II center. There were no intraprocedural complications. Immediate complete FL occlusion was achieved in 12 patients; the other 2 required reintervention. One had contrast enhancement in the distal FL proximal to the CP II and was treated with coil embolization. The other patient had persistent type I endoleak at the level of the left subclavian artery (LSA) and underwent left carotid-LSA bypass and proximal stent-graft extension. One patient died due to retrograde type A aortic dissection that was not related to CP II placement. Over a mean 8-month follow-up (range 3-12), 9 patients had computed tomography angiography; 8 patients had evidence of aortic remodeling, while 1 aneurysm sac was stable. Conclusion: The CP II reduces the number of procedural steps and offers good seal, with minimal morbidity and mortality and a high rate of aortic remodeling.

Background: Presence of gas is a frequent finding on early postoperative computed tomography angiography (CTA) after endovascular aortic aneurysm repair (EVAR) with unclear clinical relevance. The aim of this study is to examine and compare the presence of gas within the aneurysm sac following EVAR on early postoperative CTA after the use of carbon dioxide (CO 2 ) flushing technique with saline flushing alone., Methods: A retrospective analysis of patients undergoing standard, fenestrated EVAR (fEVAR) or branched EVAR (bEVAR) with flushing of the delivery system with CO 2 between January 2016 and August 2018 was undertaken. Data of a previous report using standard saline flushing were included. Patients were classified into 2 main groups: group 1 with saline flushing and group 2 with CO 2 flushing and 3 subgroups according to the type of endograft. The presence, position, and volume of gas in the postoperative CTA (within 10 days) was examined and analyzed in terms of anatomical and procedural risk factors., Results: Group 1 included 210 patients (mean age 73 ± 8, 84% males), while group 2 included 300 patients (mean age 70 ± 11, 68% males). Presence of gas was more common in group 1 (83, 39% vs. 64, 21%, P = 0.000). Volume of gas was larger in group 1 [0.41 mL (0.01-2.7) vs. 0.2 mL (0.02-1), P = 0.001). In standard EVAR with saline flushing (subgroup 1a), 59 patients (45%) had presence of gas with CO 2 flushing (subgroup 2a); 35 patients (25%) had presence of gas (P = 0.005). The mean gas volume was larger in subgroup 1a compared to 2a (0.40 ± 0.47 vs. 0.15 ± 0.17 mL, P = 0.000). The location of the gas was more frequent in contact with the anterior wall of the aorta in both groups, standard EVAR subgroups and fEVAR subgroups. The presence of gas in group 2 was associated with larger preoperative size of the aortic diameter (P = 0.03) and larger perfused lumen diameter (P = 0.05). The type of the graft was not associated with the presence of gas in the aneurysm sac on postoperative CTA. However, the presence of gas was more frequent in standard EVAR than fEVAR and bEVAR. Endoleak type II was not associated with the presence of gas., Conclusions: CO 2 flushing of stent grafts during standard and complex EVAR prior to deployment reduces the frequency and volume of gas on postoperative CTA. This study indicates that the CO 2 flushing technique may effectively exchange trapped air for a less harmful gas in endografts., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Purpose: To present a methodology for aortic arch anatomy measurement to plan and size an arch endograft with 3 inner branches., Technique: The arch endograft is custom manufactured with 3 inner side branches. Computed tomography angiography should be used to measure the clock position, the distances between the supra-aortic vessels, and the length and diameter of the proximal and distal landing zones. On the planning sheet, the vertical axis on the grid represents the spiral stabilizing wire at the 12 o'clock position; the horizontal baseline at 0 mm represents the idealized proximal margin of the innominate artery (IA). The first inner branch for the IA would be at 12:30 clock position and -20 mm from the horizontal baseline, while the second inner branch would be at the 11:30 clock position and at 0 mm. The third inner branch would vary among the different potential positions., Conclusion: Preoperative measurements of aortic arch anatomy can be made using a standard methodology to plan the size and position of inner branches. Future studies will show the potential applicability of a standard 3-inner-branch arch endograft using the planning sheet.

Introduction: Endovascular repair of infra-renal aortic aneurysm (EVAR) has become treatment of choice. However, individuals undergoing EVAR have a high re-intervention rate. The aim of this study is to evaluate the current endovascular treatment modalities of endoleak type Ia (ET Ia) treatment after EVAR and their outcome., Evidence Acquisition: A systematic review and meta-analysis was performed. MEDLINE, EMBASE and Cochrane databases were searched with PRISMA methodology for studies reporting on endovascular treatment of ET Ia after EVAR. Studies presenting treatment of intra-operative ET Ia were excluded., Evidence Synthesis: Two international registries, fourteen non-randomized retrospective and twelve case-report studies were included reporting on 356 patients. Reported endovascular techniques included fenestrated-, branched-, chimney EVAR, endovascular sealing (EVAS), endoanchors, embolization techniques, cuff and/or "giant" Palmaz stents. Technical success rate ranged from 90% to 100%, with intra-operative mortality rate of 0%. During early period, persistence of ET Ia was 3.4% (9/262) and the re-intervention rate was 3.5% (8/227). The 30-day mortality rate was 2% (7/356). Mean follow-up was 22.4 months±18. Presence of ET Ia was 5.9% (21/356), and the reintervention rate was 5.1% (18/349). The mortality rate was 13% (26/203), while the primary patency rate of TVs ranged from 94.3% to 100%., Conclusions: A multitude of techniques for endovascular repair for ET Ia exists. No strong evidence supports one specific technique. The early and mid-term outcomes are encouraging in terms of ET Ia resolution, mortality and morbidity rates.

Objectives: Infection of the vascular graft represents one of the most threatening complications after aortic repair. It is rare and associated with high morbidity and mortality rates. The aim of this study was to present short-term outcomes after surgical treatment of infected aortic grafts after endovascular and open repair of abdominal aortic aneurysms (AAAs)., Methods: Data of all patients affected by aortic graft infection after aneurysm repair who underwent an explantation of a conventional or endovascular aortic graft between January 2008 and December 2016 were retrospectively reviewed. All patients underwent in situ reconstruction using a rifampicin soaked synthetic graft. The primary endpoint of this study was 30 day mortality; secondary endpoints were major post-operative complications., Results: Twenty-six patients were included in the cohort, 16 with an infected endograft (iEVAR) and 10 patients with an infected conventional graft (iOAR). Thirty-day mortality was 23.1% overall, 37.5% for iEVAR and 0% (p = .027) for iOAR. Post-operative major complications occurred in eight (50%) patients from the iEVAR group and in four (40%) patients from the iOAR group (p = .619). The supravisceral clamping rate was higher in patients with infected iEVAR (93.8 vs. 20%, p = .001), furthermore a greater incidence of post-operative acute kidney injury was observed (50 vs. 0%, p = .009)., Conclusions: Explantation of the graft and in situ reconstruction for aortic graft infection is accepted as the therapy of choice. However, re-operation for iEVAR is related to significantly higher mortality and morbidity rates. The need for suprarenal aortic clamping seems to be a possible explanation for worse outcomes in iEVAR., (Copyright © 2018 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)

Objective: The objective of this study was to analyze radiation risk to patients during endovascular aneurysm repair (EVAR) using mobile C-arm (MA) or fixed C-arm (FA) fluoroscopes and to describe the dose distribution during the different phases of the procedure., Methods: Patients treated with EVAR using a single stent graft system between November 2009 and June 2016 were included in this study. The patients were divided into one of two groups (MA or FA) according to the type of C-arm used in the procedure. Data regarding patients' demographics and the total amount of contrast agent (CA) used, dose-area product, and fluoroscopy time for the procedures were prospectively recorded. Based on the dose report from the FA system, five standard and two optional phases of the procedure were identified to determine the dose distribution., Results: Overall, 160 patients were included (mean age, 73.30 ± 8.97 years; 146 men); of these, 107 were treated with an MA system and 53 were treated with an FA system. The mean amounts of CA used were 108.55 ± 42.28 mL in the MA group and 85.37 ± 38.79 mL in the FA group (P = .0014). The mean total dose-area product values were 49.93 ± 38.06 Gy·cm 2 in the MA group and 168.34 ± 146.92 Gy·cm 2 in the FA group (P < .0001). There was no significant difference in fluoroscopy time between the groups. Per-phase analysis demonstrated that identification of the proximal landing zone and main body deployment required the most radiation, accounting for 24% of the total radiation dose. Overall, 47.6% of the exposure was due to digital subtraction angiography., Conclusions: Use of an FA system can significantly reduce the amount of CA needed but may also lead to higher radiation doses in EVAR procedures. Dose monitoring remains crucial for the safety of both patients and operators. A detailed analysis of dose distribution is possible with modern systems, which may improve the quality of monitoring in the future., (Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Background: In recent years, biomedical devices have proven to be able to target also different neurological disorders. Given the rapid ageing of the population and the increase of invalidating diseases affecting the central nervous system, there is a growing demand for biomedical devices of immediate clinical use. However, to reach useful therapeutic results, these tools need a multidisciplinary approach and a continuous dialogue between neuroscience and engineering, a field that is named neuroengineering. This is because it is fundamental to understand how to read and perturb the neural code in order to produce a significant clinical outcome., Results: In this review, we first highlight the importance of developing novel neurotechnological devices for brain repair and the major challenges expected in the next years. We describe the different types of brain repair strategies being developed in basic and clinical research and provide a brief overview of recent advances in artificial intelligence that have the potential to improve the devices themselves. We conclude by providing our perspective on their implementation to humans and the ethical issues that can arise., Conclusions: Neuroengineering approaches promise to be at the core of future developments for clinical applications in brain repair, where the boundary between biology and artificial intelligence will become increasingly less pronounced., Competing Interests: Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article., (© The Author(s) 2018.)

Temporal lobe epilepsy (TLE) is the most common partial complex epileptic syndrome and the least responsive to medications. Deep brain stimulation (DBS) is a promising approach when pharmacological treatment fails or neurosurgery is not recommended. Acute brain slices coupled to microelectrode arrays (MEAs) represent a valuable tool to study neuronal network interactions and their modulation by electrical stimulation. As compared to conventional extracellular recording techniques, they provide the added advantages of a greater number of observation points and a known inter-electrode distance, which allow studying the propagation path and speed of electrophysiological signals. However, tissue oxygenation may be greatly impaired during MEA recording, requiring a high perfusion rate, which comes at the cost of decreased signal-to-noise ratio and higher oscillations in the experimental temperature. Electrical stimulation further stresses the brain tissue, making it difficult to pursue prolonged recording/stimulation epochs. Moreover, electrical modulation of brain slice activity needs to target specific structures/pathways within the brain slice, requiring that electrode mapping be easily and quickly performed live during the experiment. Here, we illustrate how to perform the recording and electrical modulation of 4-aminopyridine (4AP)-induced epileptiform activity in rodent brain slices using planar MEAs. We show that the brain tissue obtained from mice outperforms rat brain tissue and is thus better suited for MEA experiments. This protocol guarantees the generation and maintenance of a stable epileptiform pattern that faithfully reproduces the electrophysiological features observed with conventional field potential recording, persists for several hours, and outlasts sustained electrical stimulation for prolonged epochs. Tissue viability throughout the experiment is achieved thanks to the use of a small-volume custom recording chamber allowing for laminar flow and quick solution exchange even at low (1 mL/min) perfusion rates. Quick MEA mapping for real-time monitoring and selection of stimulating electrodes is performed by a custom graphic user interface (GUI).

Objective: The introduction of lower profile endografts expanded the application of aortic endovascular repair. However, evidence about their durability is still scarce. The objective of this study was to assess longer term durability of the Zenith Alpha Thoracic Stent Graft (Cook Inc, Bloomington, Ind) after thoracic endovascular aortic repair., Methods: Prospectively collected data of all patients treated for thoracic aortic aneurysms or penetrating aortic ulcers and having computed tomography angiography-based follow-up of ≥12 months were retrospectively analyzed. The primary end point was ongoing clinical success. Among the secondary end points, stent graft migration and fracture were analyzed., Results: Between August 2010 and October 2015, 70 consecutive patients were treated in a single center with the Zenith Alpha stent graft. With computed tomography angiography-based follow-up of 22.3 ± 15.9 months, ongoing clinical success was 87.1%. There were three cases of type IA endoleak (4.3%), two cases of type IB endoleak (2.9%), and one case of aneurysm sac enlargement (1.4%). Five patients died postoperatively (7.1%). No type III or type IV endoleak was detected; there was one case of distal stent graft migration and no stent fracture. Reintervention was necessary in one case (1.4%) of a combined type IA and type II endoleak. There were no conversions to open repair and no ruptures or intraoperative deaths. All-cause mortality was 17.1% at 76 months., Conclusions: The Zenith Alpha Thoracic Stent Graft appears to maintain favorable results in a longer time frame with a low incidence of aneurysm sac growth and migration. Results from multicenter prospective trials are needed to validate these data., (Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Whether new neurons are added in the postnatal cerebral cortex is still debated. Here, we report that the meninges of perinatal mice contain a population of neurogenic progenitors formed during embryonic development that migrate to the caudal cortex and differentiate into Satb2 + neurons in cortical layers II-IV. The resulting neurons are electrically functional and integrated into local microcircuits. Single-cell RNA sequencing identified meningeal cells with distinct transcriptome signatures characteristic of (1) neurogenic radial glia-like cells (resembling neural stem cells in the SVZ), (2) neuronal cells, and (3) a cell type with an intermediate phenotype, possibly representing radial glia-like meningeal cells differentiating to neuronal cells. Thus, we have identified a pool of embryonically derived radial glia-like cells present in the meninges that migrate and differentiate into functional neurons in the neonatal cerebral cortex., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objective: To assess the usability of a fully automated fusion imaging engine prototype, matching preinterventional computed tomography with intraoperative fluoroscopic angiography during endovascular aortic repair., Methods: From June 2014 to February 2015, all patients treated electively for abdominal and thoracoabdominal aneurysms were enrolled prospectively. Before each procedure, preoperative planning was performed with a fully automated fusion engine prototype based on computed tomography angiography, creating a mesh model of the aorta. In a second step, this three-dimensional dataset was registered with the two-dimensional intraoperative fluoroscopy. The main outcome measure was the applicability of the fully automated fusion engine. Secondary outcomes were freedom from failure of automatic segmentation or of the automatic registration as well as accuracy of the mesh model, measuring deviations from intraoperative angiography in millimeters, if applicable., Results: Twenty-five patients were enrolled in this study. The fusion imaging engine could be used in successfully 92% of the cases (n = 23). Freedom from failure of automatic segmentation was 44% (n = 11). The freedom from failure of the automatic registration was 76% (n = 19), the median error of the automatic registration process was 0 mm (interquartile range, 0-5 mm)., Conclusions: The fully automated fusion imaging engine was found to be applicable in most cases, albeit in several cases a fully automated data processing was not possible, requiring manual intervention. The accuracy of the automatic registration yielded excellent results and promises a useful and simple to use technology., (Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Purpose: To investigate the influence of the local diameter, the intraluminal thrombus (ILT) thickness, and wall stress on the local growth rate of abdominal aortic aneurysms., Methods: The infrarenal aortas of 90 asymptomatic abdominal aortic aneurysm (AAA) patients (mean age 70 years; 77 men) were retrospectively reconstructed from at least 2 computed tomography angiography scans (median follow-up of 1 year) and biomechanically analyzed with the finite element method. Each individual AAA model was automatically sliced orthogonally to the lumen centerline and represented by 100 cross sections with corresponding diameters, ILT thicknesses, and wall stresses. The data were grouped according to these parameters for comparison of differences among the variables., Results: Diameter growth was continuously distributed over the entire aneurysm sac, reaching absolute and relative median peaks of 3.06 mm/y and 7.3%/y, respectively. The local growth rate was dependent on the local baseline diameter, the local ILT thickness, and for wall segments not covered by ILT, also on the local wall stress level (all p<0.001). For wall segments that were covered by a thick ILT layer, wall stress did not affect the growth rate (p=0.08)., Conclusion: Diameter is not only a strong global predictor but also a local predictor of aneurysm growth. In addition, and independent of the diameter, the ILT thickness and wall stress (for the ILT-free wall) also influence the local growth rate. The high stress sensitivity of nondilated aortic walls suggests that wall stress peaks could initiate AAA formation. In contrast, local diameters and ILT thicknesses determine AAA growth for dilated and ILT-covered aortic walls., (© The Author(s) 2016.)

Use of endovascular means is gaining ever greater acceptance in the treatment of aorto-iliac aneurysms. Especially, the treatment of patients with common iliac aneurysms (CIAs) may be very challenging due to the complexity of the underlying disease with often involvement of the hypogastric artery. Additionally, the variety of endovascular therapeutic options such as the use of iliac branch devices, parallel grafts, the bell-bottom technique or coil embolization of the hypogastric artery and overstenting of the origin represents significant limitation regarding the presentation of a clear and robust endovascular therapeutic algorithm. Aim of the present article was the demonstration of the institutional experience with the endovascular management of CIAs in order to provide a clinical recommendation and algorithm.

We report on our experience with a simplified elephant trunk (ET) procedure with a multi-branched prosthesis (Vascutek(®) Siena™ Collared Graft). It consists of a proximal portion (20 cm) with prefabricated side branches, a collar and a distal portion (30 cm). The collar, which can be trimmed into any desired diameter, constitutes the suture portion to the descending aorta. Radiopaque markers in the distal portion indicate the landing zone. Between January 2011 and June 2013, 20 consecutive patients (10 women; mean age, 66 ± 9.3 years) underwent ET procedure, including 6 re-do cases. Underlying aortic diseases were acute dissection (n = 6), chronic dissection (n = 4), aneurysm (n = 8) and PAU (n = 2). Mean preoperative diameter of the descending aorta was 49.1 ± 12.9 mm (range 74.7-29.7 mm). Concomitant procedures included ascending aortic replacement in 16 patients; root replacement in 2; AVR in 2, CABG in 3 and mitral repair in 1 patient. CPB time was 263 ± 94 min; mean duration of ACP was 65 ± 14 min. Two patients died on POD 8 and 78, respectively. Major adverse events included stroke (n = 1), resternotomy for bleeding (n = 2), renal failure requiring temporary dialysis (n = 1) and recurrent nerve paresis (n = 2). After a mean follow-up of 10 ± 8 months, all discharged patients were alive. Seven patients underwent stent-graft implantation of the descending aorta and one patient underwent open descending aortic replacement. The last generation of multi-branched arch prosthesis and especially the Vascutek(®) Siena™ Collared Graft make ET procedure a reasonable treatment option even in patients with acute aortic dissection.

Objective: The introduction of fenestrated and multibranched endografting transformed the treatment paradigm of patients with thoracoabdominal aortic aneurysms (TAAAs). However, despite the minimally invasive character of the procedure, spinal cord ischemia (SCI) remains a devastating complication. The aim of this study was to address the SCI rates after endovascular TAAA repair and to analyze potential risk factors leading to this complication., Methods: A consecutive cohort of patients with nonruptured TAAAs treated by means of fenestrated and multibranched endografting between January 2010 and September 2014 was analyzed. Neurologic examination was routinely performed by an independent neurologist before operation and at discharge. The main outcome measure was the onset of SCI (paraplegia or paraparesis). Secondary outcomes were neurologic complications associated with cerebrospinal fluid drainage (CSFD) and 30-day mortality. Finally, a multivariate regression analysis identified risk factors for SCI., Results: A consecutive 142 patients with TAAAs (Crawford type II, n = 54 [38%]; type III, n = 76 [54%]; type IV, n = 12 [8%]) were included in this study. The majority of patients (n = 129 [91%]) were treated for an atherosclerotic aneurysm, whereas 13 patients (9%) were treated for a postdissection aneurysm. The mean maximal aortic diameter was 65 ± 13 mm. SCI developed in 23 patients (16%; paraplegia in 12 [8%] and paraparesis in 11 [8%]). Of these 23 patients, 10 patients (43%) showed the neurologic deficit directly after the procedure, 11 patients (48%) in the first 24 hours, and 2 patients (9%) after 24 hours. There was an improvement of the neurologic status in the majority of patients, with only three patients (2%) showing irreversible paraplegia at discharge. There was no difference in the 30-day mortality between patients with and without SCI (no SCI, n = 3 [3%] vs SCI, n = 1 [4%]; P = .511). Prophylactic use of CSFD before the procedure was performed in 64 patients (45%), and among them, 4 patients (6%) developed a CSFD-associated complication. No clinical benefit for patients receiving prophylactic placement of CSFD was found (P = .498). The multivariate analysis revealed the percentage of thoracic aortic coverage as the only significant risk factor for SCI (odds ratio, 1.03; 95% confidence interval, 1.01-1.05; P = .001)., Conclusions: The SCI rate after endovascular repair of TAAA was 16%, with 8% of those patients suffering from paraplegia. Prophylactic use of CSFD could not reduce the SCI rate and was associated with 6% adverse events. The percentage of thoracic aortic coverage was the most powerful determinant of SCI in these series., (Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Purpose: To assess safety and short-term efficacy of endovascular repair of the thoracic aorta with the new Zenith Alpha stent-graft., Methods: Between August 2010 and May 2014, 33 patients (21 men; mean age 73.2±9.0 years) were treated Zenith Alpha stent-graft (group ZA). Outcomes of this group were compared with those of 34 patients (25 men; mean age 70.3±8.5 years) treated contemporaneously with the Zenith TX-2 for the same pathologies (group TX). The primary outcome measure was technical success. Data on iliac tortuosity, minimum access vessel diameter, and previous unsuccessful treatment with other endografts was also recorded., Results: Technical success was 93.9% in group ZA and 91.2% in group TX (p=0.67). There was no case of surgical death or conversion to open repair in either group. Two (6%) type I endoleaks occurred in group ZA and 3 (9%) in group TX (p=0.67). Three patients died within 30 days in group ZA vs. none in group TX (p=0.07). Mean minimum access vessel diameter was significantly smaller (5.07 vs. 6.65 mm, p=0.002) and iliac tortuosity indices significantly higher in group ZA (1.34 vs. 1.25, p=0.02). Access vessel complications occurred in 1 (3%) patient in group ZA and 4 (12%) patients in group TX (p=0.17). Significantly more patients in group ZA (6, 18%) were unsuccessfully treated previously with other endografts vs. none in group TX (p=0.01)., Conclusion: The new Zenith Alpha appears to be equally as safe and efficacious as the Zenith TX-2 while being used in patients with demanding access vessel morphology., (© The Author(s) 2015.)

Background: Monitoring the expansion of abdominal aortic aneurysms (AAAs) is critical to avoid aneurysm rupture in surveillance programs, for instance. However, measuring the change of the maximum diameter over time can only provide limited information about AAA expansion. Specifically, regions of fast diameter growth may be missed, axial growth cannot be quantified, and shape changes of potential interest for decisions related to endovascular aneurysm repair cannot be captured., Methods: This study used multiple centerline-based diameter measurements between the renal arteries and the aortic bifurcation to quantify AAA growth in 51 patients from computed tomography angiography (CTA) data. Criteria for inclusion were at least 1 year of patient follow-up and the availability of at least two sufficiently high-resolution CTA scans that allowed an accurate three-dimensional reconstruction. Consequently, 124 CTA scans were systematically analyzed by using A4clinics diagnostic software (VASCOPS GmbH, Graz, Austria), and aneurysm growth was monitored at 100 cross-sections perpendicular to the centerline., Results: Monitoring diameter development over the entire aneurysm revealed the sites of the fastest diameter growth, quantified the axial growth, and showed the evolution of the neck morphology over time. Monitoring the development of an aneurysm's maximum diameter or its volume over time can assess the mean diameter growth (r = 0.69, r = 0.77) but not the maximum diameter growth (r = 0.43, r = 0.34). The diameter growth measured at the site of maximum expansion was ~16%/y, almost four times larger than the mean diameter expansion of 4.4%/y. The sites at which the maximum diameter growth was recorded did not coincide with the position of the maximum baseline diameter (ρ = 0 .12; P = .31). The overall aneurysm sac length increased from 84 to 89 mm during the follow-up (P < .001), which relates to the median longitudinal growth of 3.5%/y. The neck length shortened, on average, by 6.2% per year and was accompanied by a slight increase in neck angulation., Conclusions: Neither maximum diameter nor volume measurements over time are able to measure the fastest diameter growth of the aneurysm sac. Consequently, expansion-related wall weakening might be inappropriately reflected by this type of surveillance data. In contrast, localized spots of fast diameter growth can be detected through multiple centerline-based diameter measurements over the entire aneurysm sac. This information might further reinforce the quality of aneurysm surveillance programs., (Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

4-Aminopyridine (4AP, 50 μM) induces interictal- and ictal-like discharges in brain slices including parahippocampal areas such as the entorhinal cortex (EC) but the relation between these two types of epileptiform activity remains undifined. Here, by employing field potential recordings in rat EC slices during 4AP application, we found that: (i) interictal events have a wide range of duration (0.4-3.3 s) and interval of occurrence (1.4-84 s); (ii) ictal discharges are either preceded by an isolated "slow" interictal discharge (ISID; duration=1.5 ± 0.1s, interval of occurrence=33.8 ± 1.8 s) or suddenly initiate from a pattern of frequent polispike interictal discharge (FPID; duration=0.8 ± 0.1 s; interval of occurrence=2.7 ± 0.2 s); and (iii) ISID-triggered ictal events have longer duration (116 ± 7.3s) and interval of occurrence (425.8 ± 42.3 s) than those initiating suddenly during FPID (58.3 ± 7.8 s and 202.1 ± 21.8 s, respectively). Glutamatergic receptor antagonists abolished ictal discharges in all experiments, markedly reduced FPIDs but did not influence ISIDs. We also discovered that high-frequency oscillations (HFOs, 80-500 Hz) occur more frequently during ISIDs as compared to FPIDs, and mainly coincide with the onset of ISID-triggered ictal discharges. These findings indicate that interictal events may define ictal onset features resembling those seen in vivo in low-voltage fast activity onset seizures. We propose a similar condition to occur in vivo in temporal lobe epileptic patients and animal models., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Deep brain stimulation (DBS) is a promising tool for treating drug-resistant epileptic patients. Currently, the most common approach is fixed-frequency stimulation (periodic pacing) by means of stimulating devices that operate under open-loop control. However, a drawback of this DBS strategy is the impossibility of tailoring a personalized treatment, which also limits the optimization of the stimulating apparatus. Here, we propose a novel DBS methodology based on a closed-loop control strategy, developed by exploiting statistical machine learning techniques, in which stimulation parameters are adapted to the current neural activity thus allowing for seizure suppression that is fine-tuned on the individual scale (adaptive stimulation). By means of field potential recording from adult rat hippocampus-entorhinal cortex (EC) slices treated with the convulsant drug 4-aminopyridine we determined the effectiveness of this approach compared to low-frequency periodic pacing, and found that the closed-loop stimulation strategy: (i) has similar efficacy as low-frequency periodic pacing in suppressing ictal-like events but (ii) is more efficient than periodic pacing in that it requires less electrical pulses. We also provide evidence that the closed-loop stimulation strategy can alternatively be employed to tune the frequency of a periodic pacing strategy. Our findings indicate that the adaptive stimulation strategy may represent a novel, promising approach to DBS for individually-tailored epilepsy treatment., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objective: To present endovascular techniques in the treatment of juxtarenal aortic aneurysms (JAAAs) in relation to surgical repair; this is the "gold standard.", Methods: Between January 2008 and December 2010, 90 consecutive patients were diagnosed with primary degenerative JAAAs (≥5.0 cm) and assigned prospectively to different operative strategies on the basis of morphologic and clinical characteristics. In particular, 59 patients were treated by endovascular means such as fenestrated endovascular abdominal aortic repair (f-EVAR, n = 29) or chimney endovascular abdominal aortic repair (ch-EVAR, n = 30) endografting, and 31 patients underwent open repair (OR, n = 31)., Results: Early procedure-related and all-cause (30-day) procedure-related mortality was 0% for the endovascular group and 6.4% (n = 2/31) for the OR group, due to systemic inflammatory response syndrome with consecutive multi-organ failure (P = .023). Persistent postoperative hemodialysis occurred only after OR (2/31; 6.4%). The overall estimated pre- and postoperative median estimated glomerular filtration rate and creatinine values were similar in the three subgroups. There was one left renal artery occlusion for each endovascular subgroup, which presented as flank pain and was treated by iliaco-renal bypass in both cases. Transfusion requirements and length of hospital stay were significantly less in the endovascular group (P = .014 and P = .004, respectively)., Conclusions: Endovascular treatment of JAAA is a safe alternative for the short-term management of JAAA., (Copyright © 2012 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Deep brain stimulation (DBS) is a promising therapeutic approach for epilepsy treatment. Recently, research has focused on the implementation of stimulation protocols that would adapt to the patients need (adaptive stimulation) and deliver electrical stimuli only when it is most useful. A formal mathematical description of the effects of electrical stimulation on neuronal networks is a prerequisite for the development of adaptive DBS algorithms. Using tools from non-linear dynamic analysis, we describe an evidence-based, mathematical modeling approach that (1) accurately simulates epileptiform activity at time-scales of single and multiple ictal discharges, (2) simulates modulation of neural dynamics during epileptiform activity in response to fixed, low-frequency electrical stimulation, (3) defines a mapping from real-world observations to model state, and (4) defines a mapping from model state to real-world observations. We validate the real-world utility of the model's properties by statistical comparison between the number, duration, and interval of ictal-like discharges observed in vitro and those simulated in silica under conditions of repeated stimuli at fixed-frequency. These validation results confirm that the evidence-based modeling approach captures robust, informative features of neural network dynamics of in vitro epileptiform activity under periodic pacing and support its use for further implementation of adaptive DBS protocols for epilepsy treatment., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Background: To present the clinical experience of consecutive series with use of balloon-expandable and self-expanding chimney endografts (balloon-expandable covered stent group [BECS] vs self-expanding covered stent group [SECS]) in the endovascular treatment of challenging aortic pathologies requiring renal and/or visceral revascularization., Methods: Between January 2009 and May 2011, data for 37 high-risk patients from one center and 35 patients from another institution, with pararenal aortic pathologies treated by the chimney endovascular technique, were prospectively collected. The chimney-graft technique is based on the deployment of a covered or bare-metal stent parallel to the aortic endograft, thereby creating a conduit that runs outside the aortic main endograft, and has been proposed to ensure secure proximal fixation extending the sealing zones., Results: Forty-six consecutive target vessels (43 renal arteries and 3 superior mesenteric arteries) were revascularized by the Advanta (Atrium, Hudson, NH) BECS (1.2 chimneys/patient); in contrast, 81 consecutive target vessels (64 renal arteries, 11 superior mesenteric arteries, and 6 celiac trunks) were revascularized by the Viabahn (Gore, Flagstaff, Ariz) SECS (2.3 chimneys/patient). The success rate for target vessel preservation was 97.8% for the BECS group and 100% for the SECS group in the entire follow up. There was one symptomatic left renal artery occlusion of the BECS group treated by open thrombectomy of the left renal artery and placement of 8-mm Dacron (BBraun, Aesculap AG, Tuttlingen, Germany) iliorenal bypass. Additionally, one patient underwent repeat balloon angioplasty with a 5-mm balloon due to high-grade in-stent stenosis of a 6 × 59 Advanta stent graft 12 months postoperatively. Overall, one perioperative (and not present in the computed tomography angiography at discharge) type Ia endoleak was detected in the BECS group. In contrast, five perioperative type Ia endoleaks were present in the SECS group; however, only one of them was persistent in the radiological imaging and was treated by proximal extension of a 5-mm cuff, 1 year postoperatively, due to continuous aneurismal sac increase. No patient of any subgroup developed postoperative persistent renal insufficiency with need of hemodialysis. Thirty-day and during the follow-up procedure-related mortality was 0% for both BECS and SECS groups., Conclusions: In summary, midterm results of use of covered chimney stents for pararenal aortic pathologies show safety and feasibility with excellent patency and low incidence of endoleaks., (Copyright © 2012 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Purpose: The piriform cortex (PC) is known to be epileptic-prone and it may be involved in the manifestation of limbic seizures. Herein, we have characterized some electrophysiologic and pharmacologic properties of the spontaneous epileptiform activity generated by PC networks maintained in vitro., Methods: We performed field potential recordings from the PC in coronal or sagittal rat brain slices along with pharmacologic manipulations of γ-aminobutyric acid (GABA)ergic and glutamatergic signaling during application of the convulsant drug 4-aminopyridine (4AP, 50 μm)., Key Findings: Coronal and sagittal preparations generated interictal-like and ictal-like epileptiform discharges with similar duration and frequency. Ictal-like discharges in sagittal slices were initiated mostly in the PC anterior subregion, whereas interictal activity did not have any preferential site of origin. In sagittal slices, high frequency oscillations (HFOs) at 80-200 Hz were detected mainly at the beginning of the ictal discharge in both posterior and anterior subregions. N-Methyl-d-aspartate (NMDA) receptor antagonism abolished ictal discharges, but failed to influence interictal activity. In the absence of ionotropic glutamatergic transmission, PC networks generated slow, GABA receptor-dependent events. Finally, GABA(A) receptor antagonism during application of 4AP only, abolished ictal discharges and disclosed recurrent interictal activity., Significance: Our findings demonstrate that PC networks can sustain in vitro epileptiform activity induced by 4AP. HFOs, which emerge at the onset of ictal activity, may be involved in PC ictogenesis. As reported in several cortical structures, ionotropic glutamatergic neurotransmission is necessary but not sufficient for ictal discharge generation, a process that also requires operative GABA(A) receptor-mediated signaling., (Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.)

GABAergic function of the subiculum is central to the regulation of hippocampal output activity. Subicular neuronal networks are indeed under potent control by local inhibition. However, information about the properties of GABAergic currents generated by neurons of this parahippocampal area in normal tissue is still missing. Here, we describe GABA(A) receptor (GABA(A)R)-mediated phasic and tonic currents generated by principal cells (PCs) and interneurons (INs) of the rat subiculum. We show that in spite of similar synaptic current densities, INs generate spontaneous IPSCs (sIPSCs) that occur less frequently and exhibit smaller charge transfer, thus receiving less synaptic total current than PCs. Further distinction of PCs between intrinsically bursting (IB) and regular-spiking (RS) neurons suggested that sIPSCs generated by the two PC sub-types are likely to be similar. PCs and INs are also controlled by a similar tonic inhibition. However, whereas a comparable tonic current density is found in RS cells and INs, IB neurons are constrained by a greater inhibitory tone. Finally, pharmacological blockade of GABA(A)R did not promote functional switch of RS neurons to IB mode, but influenced the bursting propensity of IB cells and released fast spiking activity in INs. Our findings reveal differences in GABAergic currents between PCs and INs as well as within PC sub-types. We propose that GABAergic inhibition may shape hippocampal output activity by providing cell type-specific fine-tuning of subicular excitatory and inhibitory drives.

Introduction: The purpose of this study was to report the early and late results of primary stenting for focal atherosclerotic lesions of the infrarenal aorta., Methods: A retrospective analysis of 52 consecutive patients treated for infrarenal occlusive aortic disease with primary stenting between January 2002 and November 2009 was performed. Original angiographic imaging, medical records, and noninvasive testing were reviewed. Primary stenting was the first line of treatment. Perioperative technical success and Kaplan-Meier estimates for patency and survival were calculated., Results: The majority of the patients (43) were treated for severe claudication (Rutherford III; 82.7%), 5 for ischemic rest pain (Rutherford IV; 9.6%), and 4 for minor tissue loss (Rutherford V; 7.7%). Aortic stenosis was found in 40 cases (76.9%) and occlusion in 12 (23%). Perioperative hemodynamic success was 100%. All patients had an improvement of ankle brachial index (ABI) >0.10. Clinical improvement was found in 96%. Early surgical revision was necessary for aortic rupture in 1 patient. One death occurred for pneumonia. The mean follow-up time was 39.4 ± 27.2 months. Ten reinterventions (19%) were needed for symptom recurrence. The estimated assisted primary patency at 9 years was 96% and the mean survival time was 86.6 months., Conclusion: Primary stenting offers safe and durable results and should be considered as the first line of treatment for focal aortic lesions., (Copyright © 2011 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Background: A great deal of attention has been directed at the necessity and potential for deleterious outcomes as a result of radiation exposure during diagnostic evaluations and interventional procedures. We embarked on this study in an attempt to accurately determine the amount of radiation exposure given to patients undergoing complex endovascular aortic repair. These measured doses were then correlated with radiation dose estimates provided by the imaging equipment manufacturers that are typically used for documentation and analysis of radiation-induced risk., Methods: Consecutive patients undergoing endovascular thoracoabdominal aneurysm (eTAAA) repair were prospectively studied with respect to radiation dose. Indirect parameters as cumulative air kerma (CAK), kerma area product (KAP), and fluoroscopy time (FT) were recorded concurrently with direct measurements of dose (peak skin dose [PSD]) and radiation exposure patterns using radiochromatic film placed in the back of the patient during the procedure. Simultaneously, operator exposure was determined using high-sensitivity electronic dosimeters. Correlation between the indirect and direct parameters was calculated. The observed radiation exposure pattern was reproduced in phantoms with over 200 dosimeters located in mock organs, and effective dose has been calculated in an in vitro study. Scatter plots were used to evaluate the relationship between continuous variables and Pearson coefficients., Results: eTAAA repair was performed in 54 patients over 5 months, of which 47 had the repair limited to the thoracoabdominal segment. Clinical follow-up was complete in 98% of the patients. No patients had evidence of radiation-induced skin injury. CAK exceeded 15 Gy in 3 patients (the Joint Commission on Accreditation of Healthcare Organizations [JCAHO] threshold for sentinel events); however, the direct measurements were well below 15 Gy in all patients. PSD was measured by quantifying the exposure of the radiochromatic film. PSD correlated weakly with FT but better with CAK and KAP (r = 0.55, 0.80, and 0.76, respectively). The following formula provides the best estimate of actual PSD = 0.677 + 0.257 CAK. The average effective dose was 119.68 mSv (for type II or III eTAAA) and 76.46 mSv (type IV eTAAA). The operator effective dose averaged 0.17 mSv/case and correlated best with the KAP (r = 0.82, P < .0001)., Conclusion: FT cannot be used to estimate PSD, and CAK and KAP represent poor surrogate markers for JCAHO-defined sentinel events. Even when directly measured PSDs were used, there was a poor correlation with clinical event (no skin injuries with an average PSD >2 Gy). The effective radiation dose of an eTAAA is equivalent to two preoperative computed tomography scans. The maximal operator exposure is 50 mSv/year, thus, a single operator could perform up to 294 eTAAA procedures annually before reaching the recommended maximum operator dose., (Copyright © 2011 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

A totally endovascular approach to complex aortic aneurysms using fenestrated and branched stent-grafts is a technically demanding alternative to open surgical repair of thoracoabdominal and pararenal aneurysms. Complications of these complex endovascular reconstructions are varied, from dislocation of the stent-graft to occlusion of the target vessels. Based on our growing experience with these procedures, we reviewed the causes leading to secondary procedures after ≥100 branched/fenestrated stent-graft repairs and now propose several alterations to the technique that could improve the results of this approach to complex aortic aneurysm repair.

Exposure to cholinergic agonists is a widely used paradigm to induce epileptogenesis in vivo and synchronous activity in brain slices maintained in vitro. However, the mechanisms underlying these effects remain unclear. Here, we used field potential recordings from the lateral entorhinal cortex in horizontal rat brain slices to explore whether two different K(+) currents regulated by muscarinic receptor activation, the inward rectifier (K(IR)) and the M-type (K(M)) currents, have a role in carbachol (CCh)-induced field activity, a prototypical model of cholinergic-dependent epileptiform synchronization. To establish whether K(IR) or K(M) blockade could replicate CCh effects, we exposed slices to blockers of these currents in the absence of CCh. K(IR) channel blockade with micromolar Ba(2+) concentrations induced interictal-like events with duration and frequency that were lower than those observed with CCh; by contrast, the K(M) blocker linopirdine was ineffective. Pre-treatment with Ba(2+) or linopirdine increased the duration of epileptiform discharges induced by subsequent application of CCh. Baclofen, a GABA(B) receptor agonist that activates K(IR), abolished CCh-induced field oscillations, an effect that was abrogated by the GABA(B) receptor antagonist CGP 55845, and prevented by Ba(2+). Finally, when applied after CCh, the K(M) activators flupirtine and retigabine shifted leftward the cumulative distribution of CCh-induced event duration; this effect was opposite to what seen during linopirdine application under similar experimental conditions. Overall, our findings suggest that K(IR) rather than K(M) plays a major regulatory role in controlling CCh-induced epileptiform synchronization., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Background: Endovascular repair of complex aortic aneurysms (CAAs) can be performed in high-risk individuals, yet is still associated with significant morbidity, including spinal cord ischemia, cardiac complications, and death. This analysis was undertaken to better define the cardiac risk for CAA., Methods: A prospective database of patients undergoing thoracoabdominal or juxtarenal aortic aneurysm repair with branched and fenestrated endografts was used to retrospectively determine the number of cardiac events, defined as myocardial infarction (MI), atrial fibrillation (AF), and ventricular arrhythmia (VA), that occurred ≤ 30 days of surgery. Postoperative serial troponin measurements were performed in 266 patients. Any additional available cardiac information, including preoperative echocardiography, physiologic stress tests, and history of cardiac disease, was obtained from medical records. The efficacy of preoperative stress testing and the association of various echo parameters were evaluated in the context of cardiac outcomes using univariable and multivariable logistic regression models., Results: Between August 2001 and December 2007, 395 patients underwent endovascular repair of a thoracoabdominal or juxtarenal aortic aneurysm. The incidence of AF, VA, and 30-day cardiac-related death was 9%, 3%, and 2%, respectively. Overall 30-day mortality was 6%. Univariable analysis showed the presence of mitral annulus calcification was associated with MI (odds ratio [OR], 3.5; 95% confidence interval [CI], 0.9-13.8; P = .07). Left atrium cavity area, ejection fraction, left ventricle mass, and left ventricular mass index were univariably associated with the presence of VA. Multivariable analysis showed only the left atrium cavity area was independently associated with VA (OR, 1.2; 95% CI, 1.0-1.5; P = .07). Stress test was done in 179 patients. Negative stress test results occurred in 152 (85%), of whom 9 (6%) sustained an MI during the 30-day perioperative course. MI occurred in 2 of the 27 patients (7%) who had a positive stress test result., Conclusions: Endovascular repair of CAA can be performed in high-risk individuals but is associated with significant cardiac risk. It remains difficult to risk stratify patients using preoperative stress testing. Echo evaluation may help to identify patients who may be more likely to develop ventricular arrhythmias in the postoperative period and thus warrant closer monitoring. Postoperative troponin monitoring of all patients undergoing repair of CAA is warranted given the overall risk of MI., (Copyright © 2011 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)