Autologous forearm arteriovenous loop vascular access, an option to be considered.

BACKGROUND: Autologous arteriovenous fistula is usually the vascular access of choice for hemodialysis in patients with chronic kidney disease. Autologous forearm loops with cephalic or basilic vein are an alternative in those cases with a suitable forearm vein but with an unsuitable radial artery; however they are rarely used and there is little reported evidence of their usefulness. Our objective is to report our results on the creation of autogenous forearm loops as vascular access for hemodialysis. METHODS: We present a prospective cohort study of autogenous forearm loop arteriovenous fistula created between 2010 and 2022, in patients with stage 4-5 chronic kidney disease. Demographic data, surgical details, vein used, follow up to 24 months, maturation, utilization, primary, assisted, and secondary patency estimations with Kaplan-Meier curves, as well as complications during follow-up, were recorded. RESULTS: During the study period, 22 autologous forearm loops were created, 14 of them with cephalic, and 8 with basilic vein. Most (59%) of the patients were men, 19 were already on dialysis and the rest started during follow-up. Sixteen patients had previous vascular accesses. One patient was lost during follow-up. Six-week maturation rate was 61.9% and utilization rate was 57.1%. 6, 12, and 24 months primary and secondary patencies were 75.4%, 59.2%, 41.5% and 85.0%, 69.5%, 56.9% respectively. In five patients an access-induced distal ischemia was diagnosed, four successfully treated and only one patient lost the access. No cases of infection or other major complications were reported. CONCLUSION: Autologous forearm loops have acceptable maturation (61.9%) and patency rates at follow-up (56.9% 2-years secondary patency). Although rarely used, they are a vascular access alternative that should be considered to preserve the proximal vasculature of the arm for future accesses.

Inflow Artery Aneurysmal Degeneration After Long Term Native Arteriovenous Fistula for Haemodialysis.

OBJECTIVE: Inflow arterial aneurysms are a rare but serious complication after long term arteriovenous fistulae (AVF), probably due to arterial wall remodelling after an increase in flow and shear stress, and kidney transplantation with immunosuppressive therapy. This study aimed to describe the outcomes of surgical treatment and long term follow up in a large cohort. METHODS: This prospective cohort study collected data from patients with a true inflow artery aneurysm after AVF creation that was surgically repaired between 2010 and 2022. Anastomotic and infected aneurysms or post-puncture pseudoaneurysms were excluded. Demographic data, access characteristics, symptoms, treatment strategies, and long term follow up were recorded; patency was estimated using Kaplan-Meier survival analysis. RESULTS: During the study period, 28 patients (64% men, mean age 60.1 years) were treated surgically for aneurysmal degeneration of the axillary or brachial (n = 23) or radial (n = 5) artery after an AVF (10 distal, 18 proximal) performed a mean of 18.3 ± SD 7.9 years previously. Most AVFs were ligated or thrombosed, while all patients except one had previously received kidney transplants. Most of the cases (n = 18) were symptomatic: 13 with pain or swelling, four with distal embolisation, and one rupture. They were repaired by aneurysm partial excision and graft interposition (11 great saphenous vein, six ipsilateral basilic vein, three cephalic vein, and two PTFE graft), ligation (n = 3), or direct end to end anastomosis (n = 3). No major complications occurred before discharge, after a mean hospital stay of 2.4 days. After a mean follow up of 4.8 ± 3.3 years, three cases presented complications: two recurrent proximal brachial aneurysms were repaired with an additional proximal interposition graft (one with further late infected pseudoaneurysm) and an asymptomatic post-traumatic graft thrombosis. Five year primary and secondary patency was 84% and 96%, respectively. CONCLUSION: Aneurysmal degeneration of the inflow artery is an unusual complication during long term follow up of AVFs. Aneurysm excision and, in general, autogenous graft interposition using the saphenous or ipsilateral arm vein is a safe and effective strategy.

Blood glucose monitoring during hospitalisation: Advanced practice nurse and semi-automated insulin prescription tools.

INTRODUCTION: Hyperglycemia is very common in hospitalized patients and is associated with worse clinical outcomes. AIMS: We implemented a clinical and educational program to improve the overall glycemic control during hospital admission, and, in patients with HbA1c > 8%, to improve their metabolic control after hospital admission. METHODS: Non-critical patients admitted to cardiovascular areas between October-2017 and February-2019. The program was led by an advanced nurse practitioner (ANP) and included a semiautomated insulin prescription tool. Program in 3 phases: 1) observation of routine practice, 2) implementation, and 3) follow-up after discharge. RESULTS: During the implementation phase the availability of HbA1c increased from 42 to 81%, and the ANP directly intervened in 73/685 patients (11%), facilitating treatment progression at discharge in 48% (de novo insulin in 36%). One-year after discharge, HbA1c in patients who were admitted during the observation phase with HbA1c > 8% (n = 101) was higher than similar patients admitted during implementation phase (8,6 ±â€¯1,5 vs. 7,3 ±â€¯1,2%, respectively, p < 0,001). We evaluated 47710 point of care capillary blood glucose (POC-glucose) in two 9 months periods (one before, one during the program) in cardiology and cardiovascular surgery wards. POC-glucose ≥250 mg/dl (pre vs. during: cardiology 10,7 vs. 8,4%, and surgery 7,4 vs. 4,5%, both p < 0,05) and <70 mg/dl (2,3 vs. 0,8% y 1,5 vs 1%, p < 0,05), respectively, improved during the program. CONCLUSIONS: The program allowed improving inpatient glycemic control, detect patients with poor glycemic control, and optimize metabolic control 1-year after discharge.

Impact of Target Visceral Vessel Anatomical Configuration on Early Complications Following Endovascular Repair of Thoracoabdominal Aortic Aneurysms.

BACKGROUND: Fenestrated and branched endovascular aortic repair (fEVAR-bEVAR) is a viable treatment option for thoracoabdominal aortic aneurysms but target visceral stent (TVS) endoleak and thrombosis remain a limiting factor. This study aims to evaluate TVS anatomy impact on 1-year risk of thrombosis and endoleak. METHODS: Patients treated with fEVAR-bEVAR for thoracoabdominal aneurysms between 2008 and 2020 in our centre were enrolled. We recorded comorbidities, operative details, 1-month postoperative CT scan (anatomical reference), and TVS behaviour: thrombosis and endoleak at 1-year follow-up. For each TVS, different points were identified using a centre-lumen-line: (A) TVS origin, (B) end of branch/fenestration, (C) visceral vessel entry, (D) end of TVS, (E) 1-cm distally. We analyzed TVS tortuosity ((centre-lumen-line/straight distance)-1, in %), image vector analysis of each segment in 2D (antero-posterior, left-right) and 3D (craneo-caudal displacement), and centre-lumen-line analysis (bending in ABC and CDE). Three independent observers performed a blind analysis, and anatomical differences between bEVAR/fEVAR, and cases with/without 1-year thrombosis and TVS endoleak, were compared using Kaplan-Meier curves (Log-Rank test), and t-test/Wilcoxon signed-ranks test respectively. RESULTS: Fifty-four patients (72 ± 713 years mean age; 182 TVS: 50 branches, 132 fenestrations) met the inclusion criteria. bEVAR cases had longer stents, with more caudal 3D angulation, and greater ABC angulated segment. After excluding bEVAR cases (low case number), 97 fEVAR TVS were analyzed. Five thrombosis and 7 endoleaks were observed. While anatomical configuration showed no association to thrombosis, it was related to endoleak: these cases presented more tortuous stents (5.97% ± 0.10, 21.40% ± 0,22, P = 0.011), with more angulated centre-lumen-line at ABC segment (5.69° ± 15.77°, 7.18° ± 7.77°, P = 0.012), and more upward-pointing stents in the origin of the stent (AB: 89.07° ± 24.46°, 109.09° ± 16.56°, P = 0.012; BC: 87.86° ± 21.10°, 113.11° ± 22.23°, P = 0.026). CONCLUSIONS: Anatomical configuration of the TVS is associated with type III endoleak, but not thrombosis, at 1-year following fEVAR. Cases with endoleak presented more tortuous stents, with a more angulated exit from the endograft, and upward-pointing of the origin of the stent.

Linoleic Acid Status in Cell Membranes Inversely Relates to the Prevalence of Symptomatic Carotid Artery Disease.

BACKGROUND AND PURPOSE: The red blood cell fatty acid composition objectively reflects the long-term dietary intake of several fatty acids. In patients undergoing carotid endarterectomy, we explored whether red blood cell status of selected fatty acids related to symptomatic carotid artery disease. METHODS: We included patients with symptomatic (n=22) and asymptomatic (n=23) carotid artery disease. We determined all-C18:1 trans, linoleic acid (LA, C18:2n6), alpha-linolenic acid (C18:3n3), and the omega-3 index (sum of eicosapentaenoic [C20:5n3] and docosahexaenoic [C22:6n3] acids) in both red blood cells and carotid plaque phospholipids by gas-chromatography. RESULTS: In a multivariate logistic regression analysis, we only observed a significant association for LA, whose red blood cell status was inversely related to symptomatic carotid artery disease (odds ratio, 0.116 [95% CI, 0.022-0.607], P=0.011, for each 1-SD increase). A similar result was observed for LA in carotid plaque phospholipids. CONCLUSIONS: Cell membrane enrichment in LA, which reflects its intake, was inversely related to symptomatic carotid disease. This increases evidence supporting a favorable role of dietary LA in vascular health.

Climatic influence on the risk of abdominal aortic aneurysm rupture.

Our aim is to examine the effects of climatic conditions on the incidence of ruptured abdominal aortic aneurysms (rAAA) in Catalonia, Spain. We combined clinical data from the Public Health official registries in Catalonia, Spain (HD-MBDS) of all rAAA with local climatic data obtained from the closest meteorological station (69 stations, National Meteorological Service: MeteoCat) from 2008 to 2017. We analyzed the median, maximum, minimum, and variability of atmospheric pressure (hPa) and air temperature (°C), solar irradiation (MJ/m2), humidity (%), accumulated precipitation (mm), median wind, and maximum flaw direction and velocity (°, m/s), recorded on the days of events, the previous day, and mean results for 3, 7, and 30 days before, as well as seasonality. Seventy-five control days were randomly selected in a 1-year period around every rAAA day at the same meteorological station, and compared. A total of 717 days and locations with rAAA were identified, and 53,775 controls were randomly selected. For the rAAA days, there were significantly lower temperatures, lower solar global irradiation, and higher mean humidity levels in all time periods (p < 0.001, p < 0.001, p < 0.05); higher atmospheric pressure variability during 1 week and 1 month before (p = 0.011, p = 0.007); and they often occurred during autumn/winter (57.6%, p < 0.001). Logistic regression identified low mean temperatures on the days of ruptures and high mean humidity the week before as independent rupture predictors. In conclusion, low median temperatures the same day and high humidity during 1 week before were identified as independent predictors of rAAA occurrence. The role of climate on pathophysiologic mechanisms may require further investigation.

Diagnostic yield of 18F-FDG PET/CT in suspected diagnosis of vascular graft infection: A prospective cohort study.

BACKGROUND: Prosthetic vascular graft infection (PVGI) is a severe complication associated with high morbidity and mortality. Clinical diagnosis is complex, requiring image testing such as CT angiography or leukocyte scintigraphy, which has considerable limitations. The aim of this study was to know the diagnostic yield of PET/CT with 18F-Fluorodeoxyglucose (18F-FDG) in patients with suspected PVGI. METHODS: We performed a prospective cohort study including 49 patients with suspected PVGI, median age of 62 ± 14 years. Three uptake patterns were defined following published recommendations: (i) focal, (ii) patched (PVGI criteria), and (iii) diffuse (no PVGI criterion). RESULTS: Sensitivity, specificity, and positive and negative predictive values for 18F-FDG-PET/CT were 88%, 79%, 67%, and 93%, respectively. 18F-FDG-PET/CT identified 14/16 cases of PVGI showing a focal (n = 10) or patched pattern (n = 4), being true negative in 26/33 cases with either a diffuse pattern (n = 16) or without uptake (n = 10). Five of the seven false-positive cases (71%) showed a patched pattern and all coincided with the application of adhesives for PVG placement. CONCLUSIONS: 18F-FDG-PET/CT is a useful technique for the diagnosis of PVGI. A patched pattern on PET/CT in patients in whom adhesives were applied for prosthetic vascular graft placement does not indicate infection.

FEVAR/BEVAR have limitations and do not always represent the preferred option for juxtarenal reconstruction.

Following the definition given by the recent ESVS guidelines, juxtarenal abdominal aortic aneurysm (JAAA) is defined as an aneurysm extending up to but not involving the renal arteries, necessitating suprarenal aortic clamping for open surgery, i.e. a short neck (<10 mm). JAAA repair always represents a challenge intervention, either by open or endovascular means, mostly related to the renal arteries involvement. Concerning endovascular repair, different options can be considered. Among them, fenestrated endografts (FEVAR) should be considered as a first option1, due to their reported safety and efficacy. However, when the anatomy is not favorable or when FEVAR devices are not available in an emergency setting for instance, other alternatives can be considered like parallel graft or chimney technique (ChEVAR). Do nothing is the last alternative when medical and anatomical circumstances are absolutely poor. In the following pages, we will review the limitations of FEVAR and branched endografts, the better indications and anatomical conditions for a successful repair with ChEVAR technique and its current clinical results reported in the literature.

Influence of On-Call Vascular Surgery Team and Off-Hour Effect on Survival after Ruptured Abdominal Aortic Aneurysm.

BACKGROUND: Ruptured abdominal aortic aneurysms (rAAAs) represent a life-threatening emergency and carry a high community and in-hospital mortality, despite treatment and protocol advances. Identifying prognostic factors like the presence of on-call vascular surgery teams at first hospital admissions or times of hospital admissions can modify hospital protocols and mechanisms to ameliorate general outcomes. The aim of this study is to analyze the influence of on-call vascular surgery teams and off-hour admissions on survival after rAAAs in Catalonia, Spain. METHODS: We used data from public health official registries (based on registration of the minimum basic data set) to collect diagnosed cases of rAAAs (ICD-9-CM [International Classification of Diseases, Ninth Revision, Clinical Modification] 441.3) between January 2008 and December 2017. Variables included patient comorbidities, aneurysm treatment and type (endovascular treatment: ICD-9-CM 39.7 or open surgery: ICD-9-CM 398.44 and 39.25), in-hospital mortality, initial hospital admissions and transfers, days and times of admission, and final treatment received. We compared intervention rates and mortalities in all samples and operated cases, in patients initially admitted into tertiary vascular centers (with on-call vascular surgery teams) and community centers (without on-call vascular surgery teams), and the "off-hour effect" (night [22:00 hr to 8:00 hr] or weekend admissions [Friday to Sunday]) in mortality and type of surgery (open or endovascular repair). RESULTS: Of 717 patients with rAAAs (92% men), 561 (78.2%) were initially admitted into tertiary vascular centers and 156 (21.8%) into community centers. The rate of operated cases and global mortality was higher when cases were initially admitted into tertiary vascular centers (388, 69.2% vs. 46, 29.5%; P < 0.001 and 63.6% vs. 88.5%, P < 0.001, respectively), but when surgery was performed (excluding palliative nonoperated cases), the postoperative mortality in both groups was comparable (47.4% vs. 60.9%, P = 0.085), in both univariate and multivariate analysis. On the other hand, patients admitted during night hours (210, 29.3%) did not reveal noteworthy differences in the overall mortality (68.6% vs. 69.2%, P = 0.860) or postoperative mortality compared to those admitted during day hours (61.0% vs. 60.4%, P = 0.880). Weekend admissions neither showed worse results (280, 39.1%, admitted during weekend: overall mortality 70.4% vs. 68.2%, P = 0.541 and postoperative mortality 51.2% vs. 47.3%, P = 0.436). No significant dissimilarities were seen either in the use of endovascular or open repair at night (42.2% vs. 46.1%, P = 0.457) or weekend (41.8% vs. 47%, P = 0.287). CONCLUSIONS: Patients with rAAAs initially admitted into tertiary vascular centers have better overall survival rates than those initially admitted into community centers, mainly because of higher rates of rejected cases in community centers. No differences were seen in terms of mortality or type of surgery in the off-hour admitted cases (night hours or during weekends).

The most relevant unmet needs in endovascular management of descending thoracic aorta.

Endovascular repair of descending thoracic aorta (DTA) is considered as first interventional option for most part of the aortic disorders. However, many unmet needs and issues are still limiting its applicability. One of the major limitations is related to the existing gaps in evidence. Clear and robust evidence is still needed in many aspects of the management of DTA pathologies. In numerous clinical scenarios, adequate trials are lacking. Besides those gaps in evidence, it is well recognized that thoracic endografting (TEVAR) is technically evolving in order to overcome technical and device-related complications and limitations. We can deploy endografts in any aortic segment: in the descending, in the ascending, in the arch, even preserving aortic branches. Nevertheless, from the pure technical point of view, current generations of endografts still need more development and improvement. Durability remains the major concern for any endovascular treatment, and thoracic endografting is not an exception. As Galenus said, the physician is only nature's assistant, thoracic endograft should also follow the natural anatomy instead of fighting against it. We will focus the following pages on the graft conformability and compliance, both related to durability and safety of thoracic endografting. We will review the current knowledge and concerns associated with the anatomical and hemodynamic modifications induced by the thoracic endograft strength, stiffness and straightness and their implications for the future thoracic endograft designs.

Brachiobasilic arteriovenous fistula with superficialisation and transposition the basilic vein in a one stage surgical technique. Five years of single experience. / Fístulas arteriovenosas nativas humerobasílicas con superficialización y trasposición en un solo acto quirúrgico. Revisión de cinco años de experiencia.

BACKGROUND: The basilic vein is a deep vein which usually requires superficialisation and surgical transposition. MATERIAL AND METHODS: This is a retrospective study of 119 BBAVF-ST in patients with stage 5D chronic kidney disease who received an implant with a one-stage surgical technique (2011-2015). The percentage of primary (PP), assisted primary (APP) and secondary (SP) permeabilities were assessed, as well as the related complications. We analysed the permeabilities using Kaplan-Meier survival curves and a univariate Log Rank analysis (Mantel-Cox). P values less than or equal to 0.05 were considered as significant. RESULTS: The mean age of the study group was 67.9years, with 63.8% of the subjects being male. A total of 57 complications were detected during the follow-up period: 24 stenosis (42.1%), 11 thrombosis (19.2%), 7 vascular access steal syndromes (12.2%), 7 upper limb oedemas (12.2%), 6 post-puncture haematomas (10.5%) and 2 infections (3.5%). The percentages of PP obtained at 1, 6, 12 and 24months were 92.4%, 79.8%, 66.3% and 52%; APP: 94.1%, 87.3%, 80.4% and 65.6%, and SP: 95%, 89.1%, 84% and 67.5%, respectively. Diabetic patients presented with significantly worse permeabilities than vascular or idiopathic patients: (P=.037, .009 and .019, respectively). CONCLUSIONS: According to the results obtained in our study, the one-stage surgical implementation of BBAVF-ST presents high permeability rates and a small number of related complications. Diabetes mellitus is a factor related to a worse surgical prognosis. Some of the biggest advantages are the greater optimisation of health resources and a shorter time in which the central venous catheter needs to remain in the body.

Vascular access surgery can be safely performed in an ambulatory setting.

INTRODUCTION:: Ambulatory surgery is associated with lower costs, but there is lack of evidence of the safety for ambulatory vascular access surgery. The objective of this study is to substantiate the safety and effectiveness of performing vascular access surgery in an ambulatory setting. METHODS:: A review of our prospectively maintained database including all vascular access open surgeries (creations and repairs) performed by our Vascular Access Unit between 2013 and 2017 was compiled. Patient comorbidities, surgery details, hospital admission conditions, and 1-week and 1-month follow-up patency and complications (death, infection, bleeding, and readmission/reintervention) were scrutinized. RESULTS:: In the last 5 years, 1414 vascular access procedures were performed (67.8% access creations, 32.2% previous access repairs) in 1012 patients. Most surgeries were performed under local anesthesia (59.2%) or axillary plexus block (38.4%) and mainly in an ambulatory setting, without overnight hospital stays (90.9%). During the first postoperative week follow-up, 9 cases (0.6%) needed readmission or reintervention; significant infection materialized in 11 (0.8%) and 10 cases (0.7%) showed noteworthy hematoma or bleeding, only three (0.2%) requiring reintervention. The primary composite endpoint of 24-h death and 1 week readmission, reintervention, infection, or bleeding was 1.9% (27 cases); 1-month access failure was 6.2%. After univariate analysis, ambulatory settings were not related to higher rates of complications or readmissions. CONCLUSION:: Arteriovenous access surgery can be safely performed in an ambulatory setting, in spite of complex cases, comorbidities, or the increasing implementation of axillary plexus blocks. Surgical results and patency are good, and complications necessitating readmission remain very low.

The best in vitro conditions for two and three parallel stenting during endovascular aneurysm repair.

OBJECTIVE: The aim of this study is to identify which endograft-parallel stent combinations and which degree of oversizing result in the most adequate fit in a juxtarenal abdominal aneurysmal neck, when using a double or triple parallel-stent (chimney) technique. METHODS: In vitro silicon, juxtarenal, abdominal aortic aneurysmal neck models of different diameters, with two and three side-branches (simulating both the renal and superior mesenteric arteries), were constructed. Two different endografts of three diameters each, with two or three parallel stents (of 6 mm and 6 mm; or 6 mm, 6 mm, and 8 mm) were tested (Endurant-II endograft [Medtronic Inc, Santa Rosa, Calif] with balloon-expandable BeGraft stent [Bentley InnoMed, Hechingen, Germany] and an Excluder endograft [W. L. Gore and Associates, Flagstaff, Ariz] with self-expanding Viabahn stent [W. L. Gore and Associates]), applying three endograft-oversizing degrees: recommended (15%), excessive (30%), and over-excessive (40%). After remodeling, using the kissing-balloon technique at 37°C (98.6°F), 36 endograft-stent-oversizing models were scanned by computed tomography. The area of the gutters, parallel-stent compression, and main endograft infolding were recorded. RESULTS: Increasing oversizing (15%, 30%, and 40%) revealed a nonsignificant propensity toward smaller gutters and similar parallel-stent compression, but it significantly augmented infolding, more in three parallel-stent models (0%, 0%, 67% and 0%, 33%, 83% of cases; P = .015 and .018, for two and three parallel-stent models; n = 36) and mainly for the Excluder-Viabahn combination. The Excluder-Viabahn showed significantly smaller gutters, but with higher stent compression, than Endurant-BeGraft combinations for both two and three parallel stents (8.2 mm2, 22.6 mm2; P = .002 and 14.4 mm2, 23.3 mm2; P = .009 gutter area; and 18%, 2%; P < .001 and 15%, 2%; P = .007 relative stent area compression, respectively). CONCLUSIONS: Better endograft stent apposition was usually attained when using 30% oversizing during two and three parallel-stent techniques. Higher oversizing was related to nonsignificant smaller gutters but higher rates of infolding. Smaller gutters, but higher stent compression and risk of infolding, were achieved with the Excluder-Viabahn than with the Endurant-BeGraft combination.

Parallel-Stenting Technique in a Sandwich Configuration for Hypogastric Artery Preservation during Endovascular Aneurysm Repair: An In Vitro Study.

BACKGROUND: The aim of the study was to identify the best conditions in iliac sandwich procedure for hypogastric artery preservation during endovascular aneurysm repair, testing different devices, different oversizing (OS) degrees as well as different methods to measure it. METHODS: Four external iliac devices (16-mm Endurant and 12-mm Aorfix limb extensions; 11- and 13-mm Viabahn endografts) were tested with 2 distinct internal iliac stent grafts (8-mm Advanta V12 and 8-mm Viabahn) inside different proximal silicon iliac limb models (10, 12, 14, 16, and 18 mm), simulating an iliac sandwich procedure for hypogastric preservation. After remodeling all devices in a saline bath at 37°C, the combinations were computed tomography scanned. Gutter size, parallel-stent compression, and inadequate parallel-stent deployment or infolding were recorded. Oversizing between both parallel stents and the iliac limb models were examined in terms of added diameter, perimeter, and area being additionally compared. RESULTS: All three sizing methods (diameter, perimeter, and area) were highly correlated (diameter OS to perimeter and area OS correlation coefficient 0.998 and 0.997, respectively, P < 0.001 for both); thus, diameter OS was used for further comparisons. Increasing diameter OS (< 30%, 30-55%, 55-75%, and > 75%) showed a significant tendency toward smaller gutters (38.9, 12.2, 5.4, and 2.6 mm2, respectively, P < 0.001) but also increasing parallel-stent compression (13.5%, 28.9%, 43.9%, and 55.1%, P < 0.001) and infolding (0%, 0%, 38%, and 60%, P < 0.001). There were no significant differences between the analyzed devices. CONCLUSIONS: In iliac sandwich procedures, better apposition is usually achieved when using 30-55% diameter OS; higher OS is related to smaller gutters but higher rates of malpositioning and parallel-stent compression. No clear recommendations in material selection can be performed. All sizing methods are highly correlated and predictable.

Aortic Arch and Thoracic Aorta Curvature Remodeling after Thoracic Endovascular Aortic Repair.

BACKGROUND: The objective of this study was to analyze the original curvature of the aortic arch and thoracic aorta, and how it is modified after the placement of a thoracic endograft. METHODS: We retrospectively analyzed all patients primarily treated for thoracic aortic aneurysms and blunt traumatic aortic injuries by means of an endograft sealed into the aortic arch (zones, Z1-Z3) in 2 different centers (Vascular Surgery Division, Hospital Clinic, UB; and Vascular and Endovascular Surgery Department, Hospital Vall d'Hebron, UAB; Barcelona, Spain), between 2010 and 2015. The last preoperative and early (1-month) postoperative computed tomography angiography (CTA) was obtained for all cases, and an accurate 3-dimensional (3D) center lumen line was created, from the aortic valve to the renal arteries. Angles in 2-dimensional (2D; XY-plane) and 3D (referred to cranial-caudal Z-axis) were analyzed in: the distal ascending aorta, aortic arch, and thoracic aorta (at 5, 10, 15, and 20 cm from the brachiocephalic trunk [BCT]) and celiac trunk (CT). Changes in preoperative-postoperative CTA were compared independently for both diseases. Thirty-six cases were included (20 aneurysms, 16 blunt traumatic injuries; mean age, 69.5 and 42.5 years). RESULTS: After placement of an aortic endograft (sealed in Z1-Z2 in 30% of aneurysms and 75% of traumatic injuries; mean endograft length: 22.6 cm and 11.3 cm, respectively), a global left anterior displacement of the ascending aorta was observed (2D examination: -13.1° and -7.5°, P = 0.049 and 0.041, respectively). The 3D examination showed an average increase of the aortic angle at 5 and 10 cm from the BCT in the whole sample (+4.0°, +4.9° in reference to the vertical; P = 0.017, 0.001), softening the curvature of the proximal descending thoracic aorta. In addition, in traumatic injuries, a decrease in the aortic arch angle was observed (-3.5°, P = 0.030). CONCLUSIONS: Placement of an endograft into the aortic arch and proximal thoracic aorta engenders a softening of the proximal descending thoracic aorta curvature, increasing its angle from the vertical. In blunt traumatic aortic injuries (with shorter and more proximally sealed endografts), an additional decrease of the aortic arch angle (3.5° more vertical), was observed.

Effect of a postoperative exercise program on arteriovenous fistula maturation: A randomized controlled trial.

Exercises after arteriovenous fistula (AVF) creation may help to improve maturation; however, their usefulness has only been examined in indirect, non-comparative studies or small trials. Between June 2013 and November 2014, we included all ambulatory patients with stages 5-5D chronic kidney disease who were candidates for the creation of a native AVF in our center. After surgery, all patients were randomized to an exercise group or a control group with single-blind control. At 1 month postoperatively, clinical maturation (expert nurse inspection) and ultrasonographic maturation (flow >500 mL/min, venous diameter >5 mm and depth <6 mm) were assessed in all patients. A total of 72 patients were randomized, 3 were lost to follow-up, and 69 were finally analyzed. The mean age was 66.8 years (standard deviation 13.8), 70.0% were men, and 65.2% were in pre-dialysis. After surgery (42.0% had distal AVF), the patients were randomized (31 controls, 38 exercise group). At 1 month after surgery, global clinical and ultrasonographic maturation was assessed in 88.4% and 78.3% of AVF, respectively (kappa = 0.539). Non-significant differences in clinical or ultrasonographic maturation were seen between exercise and control group (94.7% vs. 80.6%, P = 0.069; 81.6% vs. 74.2%, P = 0.459). A stepwise logistic regression was performed to control previously analyzed asymmetrically distributed confounding factors (AVF localization), revealing that the exercise group showed greater clinical, but not ultrasonographic, maturation (odds ratio [OR] 5.861, 95% confidence interval: 1.006-34.146 and OR 2.403, 0.66-8.754). A postoperative controlled exercise program after AVF creation seems to increase 1-month clinical AVF maturation in distal accesses. Furthermore, exercise programs should be taken into account, especially in distal accesses.