Search

Background Luminal narrowing, suspected secondary to thrombus, occurs within stent grafts at an unclear incidence after thoracic endovascular aortic repair (TEVAR). The significance of this phenomenon has not been determined, nor have the risk factors for development of intragraft luminal narrowing. Small graft diameter is hypothesized to be a risk factor for the development of ingraft stenosis. Methods A retrospective analysis was performed of a multicenter healthcare system including all patients who underwent TEVAR between July 2011 and July 2019 with at least 1 year of subsequently available surveillance contrast-enhanced computed tomography imaging. Standard demographic, preoperative, intraoperative, and postoperative variables were collected. Measurements were obtained via direct off-line images from computed tomography scans. Patent intragraft diameters were compared with baseline and interval change values were normalized to time to follow-up. The primary outcome measure was annual rate of intragraft luminal narrowing. Results There were 208 patients who met the inclusion criteria (94 women, 114 men) with a median follow-up of 822 days. The mean annual rate of percent intragraft diameter reduction was 10.5 ± 7.7% for women and 7.6 ± 5.6% for men (P = .0026). Multivariate analysis demonstrated female gender (P = .0283), preoperative diagnosis of hypertension (P = .0449), and need for coverage of the left subclavian artery (P = .0328) were all significant predictors of intragraft luminal narrowing. Small aortic diameters were not found to be associated independently with ingraft luminal narrowing nor was the concomitant use of antiplatelet or anticoagulation medications. Significant amounts of ingraft luminal narrowing, defined as a greater than 20% intragraft diameter decrease, were associated with an increased need for any reintervention, including for malperfusion, endoleak, and symptomatic aneurysm (P = .0249). Kaplan-Meier estimates demonstrated a significant gender-associated difference in high rates of intragraft luminal narrowing (P = .00189). Conclusions In this analysis, female gender is shown to be a significant nonmodifiable risk factor for intragraft luminal narrowing after TEVAR. The development of this phenomenon is not benign; as such, these findings were associated with an increased need for reintervention. This finding may be attributable to differences in aortic compliance or gender-associated differences in coagulation pathways and merits further investigation. Surveillance after thoracic stent grafting must account for patient-specific variations in complication risk.

Objective Acute iliofemoral artery thrombosis (IFAT) can occur in critically ill neonates and infants who require indwelling arterial cannulas for monitoring or as a consequence of cardiac catheterization. Guidelines suggest treatment with anticoagulation, but evidence supporting the optimal duration of therapy and the role of surveillance ultrasound is limited. The objectives of this study were to characterize the kinetics of thrombus resolution and to define an appropriate duration of anticoagulation and interval for surveillance ultrasound. Methods This was a single-center retrospective cohort study of pediatric patients with acute IFAT from 2011 to 2019. Medical records and vascular laboratory studies were reviewed. Patients with one or more surveillance ultrasound examinations were included. Thrombus resolution was defined as multiphasic flow throughout the index limb without evidence of echogenic intraluminal material by ultrasound. Time to resolution of thrombus was assessed using Kaplan-Meier analysis. Results Fifty-four limbs in 50 patients were identified with acute IFAT. The median age was 9.9 weeks (interquartile range, 3.1-21.7 weeks), with a median weight of 4.2 kg (interquartile range, 3.3-5.5 kg). The majority of limbs (65%) with acute IFAT presented with a diminished pedal Doppler signal, commonly after cardiac catheterization (55%). Forty-eight (89%) limbs had complete arterial occlusion on index ultrasound, and flow could not be detected below the ankle in 48%. The median number of ultrasound examinations per limb was three (range, two to seven), and 61% of limbs had a surveillance ultrasound within 7 days of diagnosis. At 14 and 30 days, 33% and 64% of patients, respectively, treated with anticoagulation had an estimated complete resolution of thrombus. Nine (17%) patients did not receive anticoagulation, and only two of these patients experienced IFAT resolution. At the time of diagnosis, one patient underwent open thrombectomy because of a contraindication to anticoagulation, and one patient was treated with thrombolysis. There were no instances of tissue loss or amputation Conclusions Management of IFAT with anticoagulation resulted in successful short-term outcomes. Based on the observed rate of resolution, management should start with anticoagulation, followed by surveillance ultrasound at 2-week intervals. With treatment by anticoagulation, resolution can be expected to occur in one-third of patients every 2 weeks.

Improved risk stratification is a key priority for type B aortic dissection (TBAD). Partial false lumen thrombus morphology is an emerging predictor of complications. However, partial thrombosis is poorly defined, and its evaluation in clinical studies has been inconsistent. Thus, we aimed to characterize the hemodynamic pressure in TBAD and determine how the pressure relates to the false lumen thrombus morphology and clinical events.The retrospective admission computed tomography angiograms of 69 patients with acute TBAD were used to construct three-dimensional computational models for simulation of cyclical blood flow and calculation of pressure. The patients were categorized by the false lumen thrombus morphology as minimal, extensive, proximal or distal thrombosis. Linear regression analysis was used to compare the luminal pressure difference between the true and false lumen for each morphology group. The effect of morphology classification on the incidence of acute complications within 14 days was studied using logistic regression adjusted for clinical parameters. A survival analysis for adverse aortic events at 1 year was also performed using Cox regression.Of the 69 patients, 44 had experienced acute complications and 45 had had an adverse aortic event at 1 year. The mean ± standard deviation age was 62.6 ± 12.6 years, and 75.4% were men. Compared with the patients with minimal thrombosis, those with proximal thrombosis had a reduced false lumen pressure by 10.1 mm Hg (95% confidence interval [CI], 4.3-15.9 mm Hg; P = .001). The patients who had not experienced an acute complication had had a reduced relative false lumen pressure (-6.35 mm Hg vs -0.62 mm Hg; P = .03). Proximal thrombosis was associated with fewer acute complications (odds ratio, 0.17; 95% CI, 0.04-0.60; P = .01) and 1-year adverse aortic events (hazard ratio, 0.36; 95% CI, 0.16-0.80; P = .01).We found that proximal false lumen thrombosis was a marker of reduced false lumen pressure. This might explain how proximal false lumen thrombosis appears to be protective of acute complications (eg, refractory hypertension or pain, aortic rupture, visceral or limb malperfusion, acute expansion) and adverse aortic events within the first year.

This study investigated the influence of the aortic bifurcation anatomy on the endovascular treatment of abdominal aortic aneurysms using Excluder (W. L. GoreAssociates, Flagstaff, Ariz) bifurcated stent grafts.This was a retrospective single-center study of patients treated with the Excluder stent graft. Analysis included anatomical factors of the aortic bifurcation (aortic bifurcation diameter [ABD], calcification, thrombus), characteristics of the stent graft limbs (sum of stent graft limbs diameters [SLD]), and the SLD/ABD ratio. Narrow bifurcation was defined as ABD 20 mm. Primary outcomes were intraoperative stenosis, need for additional intraoperative measures, limb stenosis, and occlusion during follow-up.The study included 232 patients. Mean ABD was 24.6 ± 6 mm, with 53 patients (23%) presenting with narrow bifurcation (range, 12.5-19.5 mm). Median SLD in these patients was 28 mm, and the SLD/ABD ratio was 1.64. Calcification involving50% of the bifurcation circumference was present in 32% of the patients, with 17% presenting thrombus in this area. Of 53 patients with narrow bifurcation, intraoperative stenosis50% occurred in three (5.7%), which required adjunctive treatment. Computed tomography at 1 month showed limb stenosis50% in nine patients (17%). No limb occlusions were recorded with a median follow-up of 34 months. Multivariate analysis of the overall series showed a higher risk of limb stenosis on the computed tomography at 1 month in patients with peripheral artery disease (hazard ratio [HR], 5.3; 95% confidence interval [CI], 1.2-24.4; P = .032), narrow bifurcation (HR, 5.7; 95% CI, 2-15.8; P = .001), higher SLD/ABD ratio (HR, 29.3; 95% CI, 4-215.2; P = .001), and calcium50% (HR, 3; 95% CI, 1.1-8; P = .03), and lower in bifurcations with thrombus (HR, 0.3; 95% CI, 0.1-0.8; P = .017).Abdominal aortic aneurysms with narrow bifurcation can be treated with the bifurcated Excluder device without additional adjunctive measures. The presence of limb stenosis during follow-up is not associated with occlusion. Long-term follow-up studies are needed to confirm these results.

The purpose of the present study was to assess the outcomes of fenestrated-branched endovascular aortic repair (FB-EVAR) using infrarenal aortic vs iliac sealing zones.We reviewed the clinical data of 430 consecutive patients enrolled in a prospective nonrandomized study to evaluate FB-EVAR from 2013 to 2020. The outcomes were analyzed for patients with extent I to IV thoracoabdominal aortic aneurysms who had undergone FB-EVAR with distal implantation in the native infrarenal aorta. The minimum anatomic criteria for the use of infrarenal aortic seal was a3-cm length of parallel aorta with a diameter of 18 to 32 mm without excessive thrombus or calcification. A control group matched for the extent of aortic disease with an iliac artery seal was used to compare the following endpoints: 30-day mortality, major adverse events, freedom from type Ib endoleak (TIbE), freedom from secondary interventions, and changes in the infrarenal aortic diameter.A total of 110 patients (55 men; mean age, 73 ± 8 years) were included in the present study, 55 with an infrarenal aortic distal seal and 55 with the iliac arteries as the sealing zone. Both groups had similar clinical characteristics and aneurysm extent and diameter, except for a greater number of men and higher serum creatinine in the iliac seal group. Technical success was obtained in 106 patients (96%) and was greater for the iliac sealing zone group (100% vs 93%; P = .04). The use of the infrarenal aortic sealing zone was associated with shorter endovascular (148 ± 56 minutes vs 191 ± 61 minutes; P .001) and fluoroscopy (76 ± 28 minutes vs 96 ± 32 minutes; P .001) times and lower radiation exposure (cumulative air kerma, 1.4 ± 1.4 Gy vs 2.1 ± 2.0 Gy; P = .02; dose area product, 147 ± 75 Gy ∙ cmInfrarenal aortic and iliac artery seal zones are safe and effective during FB-EVAR, provided the patients have suitable segments. The use of the infrarenal aortic sealing zone had modest procedural advantages such as shorter endovascular and fluoroscopy times and lower radiation exposure. No differences were found in the clinical outcomes or development of TIbEs.

To report the outcomes of thoracic endovascular aortic repair (TEVAR) for shaggy thoracic aortic aneurysms (STA). It is a single center, retrospective, observational, cohort study. Data were collected prospectively between January 2005 and May 2019. STA was defined, based on computed tomography angiography findings, as the presence of an irregular/ulcerated atheroma protruding and/or thrombus thickness ≥ 5 mm protruding into the aortic lumen, and/or occupying more than two thirds of the circumference of the aortic diameter axially. Primary outcomes were early (≤ 30 days) and late survival and freedom from major complication due to end-organ or peripheral ischemic embolization. Nine (2.3%) of 391 patients met the inclusion criteria. Mean age was 71 years ± 10 (range 55–83). Mean aneurysm diameter was 68 mm ± 0.5 (range 60–75). Four patients presented symptomatic: rupture (n = 2), blue toe syndrome (n = 2). TEVAR was performed in 7 of the 9 patients. Operative-related embolization occurred in 1 patient (transient ischemic attack and acute kidney injury). In-hospital mortality was observed in 1 patient following spinal cord ischemia and multiple organ failure development. Median follow-up was 48 months (IQR 5–84). Freedom from major complication due to end-organ or peripheral ischemic embolization was achieved in all patients. No patient developed further localization of STA in the proximal or distal aorta, and did not experience reno-visceral or peripheral atheroembolization episodes. Risk of atheroembolism in STA is still threatening but TEVAR proved to be an effective and durable treatment in this high-risk cohort.

Objective The goal of this study was to investigate the correlation between atherothrombotic aortic wall thrombus (AWT) and clinical outcomes in patients treated by fenestrated-branched endovascular aortic repair (F-BEVAR) and present a new classification system for assessment of AWT burden. Methods The clinical data of 301 patients treated for pararenal and thoracoabdominal aortic aneurysms (TAAAs) by F-BEVAR was reviewed. The study excluded 89 patients with extent I to III TAAA because of extensive laminated thrombus within the aneurysm sac. Computed tomography angiograms were analyzed in all patients to determine the location, extent, and severity of atherothrombotic AWT. The aorta was divided into three segments: ascending and arch (A), thoracic (B) and renal-mesenteric (C). Volumetric measurements (cm 3 ) of AWT were performed using TeraRecon software (TeraRecon Inc, Foster City, Calif). These volumes were used to create an AWT index by dividing the AWT volume from the total aortic volume. A classification system was proposed using objective assessment of the number of affected segments, thrombus type, thickness, area, and circumference. Clinical outcomes included 30-day mortality, neurologic and gastrointestinal complications, renal events (Risk, Injury, Failure, Loss of kidney function, End-stage renal disease [RIFLE]), and solid organ infarction. Results The study included 212 patients, 169 men (80%) and 43 women (20%), with a mean age of 76 ± 7 years. A total of 700 renal-mesenteric arteries were incorporated (3.1 ± 1 vessels/patient). AWT was classified as mild in 98 patients (46%) and was considered moderate or severe in 114 (54%). There was one death (0.5%) at 30 days. Solid organ infarction was present in 50 patients (24%), and acute kidney injury occurred in 45 patients (21%) by RIFLE criteria. An association with higher AWT indices was found for time to resume enteral diet ( P = .0004) and decline in renal function ( P = .0003). Patients with acute kidney injury 2 by RIFLE criterion had significantly higher ( P = .002) AWT index scores in segment B. Spinal cord injury occurred in three patients (1.4%) and stroke in four (1.9%), but were not associated with the AWT index. Severity of AWT using the new proposed classification system correlated with the AWT index in all three segments ( P P = .016). Conclusions AWT predicts solid organ infarction, renal function deterioration, and longer time to resume enteral diet after F-BEVAR of pararenal and type IV TAAAs. Evaluation of AWT should be part of preoperative planning and decision making for selection of the ideal method of treatment in these patients.

Background Thoracic aortic mural thrombus (TAMT) of the descending aorta is rare but can result in dramatic embolic events. Early treatment is therefore crucial; however, there is not a consensus on ideal initial treatment. Methods A review of the literature using PubMed was conducted, and all relevant publications describing descending TAMT of the past 15 years were reviewed. Variables included for this analysis were presentation, initial treatment strategy employed, outcome measures of thrombus resolution or regression, recurrence of symptomatic emboli, and mortality. Results Seventy-four patients were included in this analysis. Women were significantly more likely to be described with descending TAMT. The majority (82.4%) of cases reported were diagnosed after an embolic event. Patients were equally likely to receive medical, open surgical, or endovascular therapy as the initial treatment modality. However, there is a trend within the past 5 years to report cases describing successful thoracic endovascular aortic repair for initial management. Of patients who initially underwent medical management, nine patients (34.6%) had persistent thrombus. Of the patients who initially underwent open surgical repair, six patients (31.6%) had persistent thrombus; of these patients, four underwent endovascular repair. Twenty-nine patients (39.2%) with descending TAMT initially underwent thoracic endovascular aortic repair. Twenty-seven (93.1%) had fully excluded thrombus at the time of the procedure, with no recurrence or evidence of repeated embolic phenomena at follow-up. Conclusions Whereas mural thrombus of the thoracic aorta is uncommon, it must be considered in the differential diagnosis of embolic events. Although endovascular therapy may be a useful first-line option for TAMT with reports of positive outcomes in select literature, further study of this treatment option is required.

Objective The purpose of the study was to aggressively salvage acutely occluded arteriovenous fistulas (AVFs) using duplex imaging as the sole imaging modality for percutaneous transluminal angioplasty of acutely thrombosed AVF. Methods Over a period of 12 months, 14 patients with acute thrombosis of their AVFs underwent 18 procedures in a single center for AVF salvage. All 14 patients presented with chronic renal failure, and six were diabetic. All patients were treated under duplex guidance alone. Treatment included simple balloon dilation and maceration (group A; n =10 procedures [56%]) for subacute thrombosis or pharmacomechanical thrombectomy (group B; n = 8 procedures [44%]) for more hypoechoic thrombus. A successful procedure was defined as immediate restoration of flow through the AVF. Results Of the 18 procedures, 13 (72%) were successful. Of the 14 patients, thrombus was located at the perianastomotic AVF in 6 (43%), proximal-mid AVF in 6 (43%), mid AVF in 1 (7%), and distal AVF in 1 (7%). From group A, six (60%) were successful. From group B, seven (88%) were successful. Among the unsuccessful procedures, one group B patient was hypercoagulable (polycythemia vera). Of the 18 procedures, 16 (89%) were treated within 2 weeks from when duplex revealed the presence of thrombus. Early rethrombosis ( Conclusions The sole use of duplex ultrasound imaging to salvage acutely occluded AVFs using percutaneous transluminal angioplasty is a safe and effective alternative to traditional treatment of thrombosed failing/maturing AVF.

Objective Catheter-directed thrombolysis in the treatment of acute lower extremity arterial occlusions often requires several interventional sessions to generate successful outcomes. It is typically an expensive procedure, necessitating extended hospital length of stay (LOS) that may be associated with an increase in both local and systemic hemorrhagic complications. Five years ago, we created the fast-track thrombolysis protocol for arteries (FTTP-A) to deal with these concerns. The goal of our protocol is to re-establish patency during the first session of thrombolysis, thus decreasing costs and complications associated with prolonged periods of thrombolytic exposure. Methods A retrospective study of 42 patients who were treated for acute limb ischemia at our institution by FTTP-A from January 2014 to February 2019 was performed. FTTP-A includes periadventitial lidocaine injection at the arterial puncture site under ultrasound guidance, contrast arteriography of the entire targeted segment, pharmacomechanical rheolytic thrombectomy of the occluded arterial segment, tissue plasminogen activator infusion along the occluded segment, balloon maceration of the thrombus, and (if deemed necessary) placement of a stent in an area of significant (≥30%) stenosis that is refractory to balloon angioplasty and thrombolysis. After the stenosis or thrombus is cleared, patients are prescribed an oral anticoagulant agent. Results Primary FTTP-A (50 total interventions) was performed in 42 patients. The median age of patients was 67.2 ± 12.2 years (range, 41-98 years), and 54.8% were male; 59.5% of the procedures were performed on the left lower extremity. Initial arterial access was obtained through the common femoral artery in 39 of 42 cases (92.9%); in the remaining 3 cases, it was obtained in a left bypass access site, a right femoral-popliteal graft, and a right femoral-femoral graft. The mean operative time was 148.9 ± 62.9 minutes (range, 83-313 minutes), and the mean volume of tissue plasminogen activator infused was 9.7 ± 4.0 mg (range, 2-20 mg). The median cost including medications and interventional tools was $4673.19 per procedure. The mean postoperative LOS was 3.1 ± 4.5 days (range, 1-25 days). Median postoperative LOS was 1 day. Mean postoperative follow-up was 27 ± 19.2 months (range, 0-62 months). Single-session FTTP-A was successful in 81% (n = 34/42) of patients; the remaining 8 patients (19%) required a single additional session. Of the 42 patients, 34 (81%) required arterial stenting. Periprocedural complications consisted of one patient with hematuria, which resolved, and one patient with thrombocytopenia, which resolved. No patients experienced rethrombosis within 30 days of FTTP-A. During the 5-year study period, there was no significant local or systemic hemorrhage, limb loss, or mortality related to this protocol. Conclusions FTTP-A appears to be a safe, efficacious, and cost-effective procedure in the resolution of acute lower extremity arterial occlusions.

Objective To evaluate clinical outcomes from a postmarket registry of the Zenith Spiral-Z abdominal aortic aneurysm iliac leg graft with a continuous, spiral nitinol stent that was designed for improved conformability, kink, and migration resistance. Methods This prospective, multicenter registry was designed to evaluate physician-reported outcomes of the Spiral-Z leg graft in up to 600 patients who underwent endovascular repair of abdominal aortic or aortoiliac aneurysms at up to 30 investigative sites in the United States and Canada. Study outcomes were focused on iliac limb occlusion, limb-related reintervention, limb-related endoleak, component separation, and device integrity. Short-term data were collected during an interval of 1 to 6 months, with longer term data collected at 12 months. Results Between March 2012 and March 2015, 599 patients (mean age 74 ± 8 years; 87% male; 26% with aortoiliac aneurysm) were treated, with Spiral-Z iliac leg grafts placed in 564 left iliac arteries and 559 right iliac arteries. The mean iliac inner diameters (both left and right) were 9 ± 3 mm; moderate/severe occlusive disease, calcification, and vessel tortuosity were present in 14%, 25%, and 36% and 15%, 25%, and 34% of the left and right iliac arteries, respectively. Iliac artery adjunctive procedures (iliac artery angioplasty and/or stent placement) were performed intraoperatively in 112 patients (19%; bilateral in 52 patients). Mortality within 30 days was 1.7% (10/599); cumulative mortality at 1 year was 6.2% (37/599). There were no aortic ruptures and only one open conversion (0.2%). Limb occlusions occurred in 11 of 599 patients (2%; 3 within 30 days and 8 after 30 days, all unilateral, none had received procedural iliac artery adjuncts at implantation); of these, 7 patients underwent reinterventions. Other limb-related reinterventions were performed on eight patients for nonocclusive kink, compression, or thrombus (six within 30 days and three after 30 days). In total, 13 patients (2%) underwent 15 limb-related reinterventions (7 for occlusions and 8 for nonocclusive causes). In one patient, a distal type I endoleak and device migration (>10 mm) involving a right iliac leg was noted at the 12-month follow-up visit. No other limb-related endoleak, migration, component separation, or stent fracture was reported during a mean follow-up of 11 ± 6 months. Conclusions The Spiral-Z leg graft demonstrated excellent patency and required infrequent limb-related reinterventions in routine clinical care in a postmarket registry.

Objective The aim of the study was to determine whether magnetic resonance imaging (MRI) can be used in assessment of biologic activity of intraluminal thrombus (ILT) and proteolytic processes of the abdominal aortic aneurysm wall. Methods Using MRI, 50 patients with asymptomatic infrarenal abdominal aortic aneurysm were analyzed at the maximum aneurysm diameter on T1-weighted images in the arterial phase after administration of contrast material. Relative ILT signal intensity (SI) was determined as the ratio between ILT SI and psoas muscle SI. During surgery, the full thickness of the ILT and the adjacent part of the aneurysm wall were harvested at the maximal diameter for biochemical analysis. The concentrations of matrix metalloproteinase 9 and neutrophil elastase (NE/ELA) were analyzed in harvested thrombi, and the concentrations of collagen type III, elastin, and proteoglycans were analyzed in harvested aneurysm walls. Results A significant positive correlation was found between the NE/ELA concentration of the ILT and the relative SI (ρ = 0.309; P = .029). Furthermore, a negative correlation was observed between the elastin content of the aneurysm wall and the relative SI (ρ = −0.300; P = .034). No correlations were found between relative SI and concentration of matrix metalloproteinase 9, NE/ELA, collagen type III, or proteoglycan 4 in the aneurysm wall. Conclusions These findings indicate a potential novel use of MRI in prediction of thrombus proteolytic enzyme concentrations and the extracellular matrix content of the aneurysm wall, thus providing additional information for the risk of potential aneurysm rupture.

The objective of this study was to analyze the utility of cone beam computed tomography (CBCT) for technical assessment of standard and complex endovascular aneurysm repair (EVAR).Data of consecutive patients who underwent standard or complex EVAR in 2016 and 2017 at our institution were entered into a prospective database and analyzed retrospectively. There were 154 patients (126 male; mean age, 74 ± 8 years) enrolled in a prospective study between 2016 and 2017. A total of 170 aortic procedures were investigated, including 85 fenestrated-branched EVARs (F-BEVARs), 42 abdominal and thoracic EVARs, 32 EVARs with iliac branch devices, and 11 aorta-related interventions. Technical assessment was done using CBCT with and without contrast enhancement, digital subtraction angiography (DSA), and computed tomography angiography (CTA). Patients with stage 3B or stage 4 chronic kidney disease had CBCT without contrast enhancement. Radiation exposure (mean dose-area product), effective dose (ED), and amount of iodine contrast agent were analyzed. End points were presence of any endoleak, positive findings warranting possible intervention (stent kink or compression, type I or type III endoleak, dissection, thrombus), and need for secondary intervention.Radiation exposure and amount of iodine contrast agent were significantly higher (P .05) for F-BEVAR compared with other aortic procedures (174±101 Gy∙cmCBCT reliably detected positive findings prompting immediate revisions in nearly one of five patients, with the highest rates among F-BEVAR patients. Detection of any endoleak was higher with CBCT compared with DSA or CTA, but most endoleaks were observed. DSA alone failed to detect positive findings warranting revisions.

Intraluminal thrombus (ILT) is present in most abdominal aortic aneurysms (AAAs), although its role in AAA progression is controversial.A literature search was performed to identify studies that investigated the association between ILT volume and AAA rupture. A study assessment tool was developed to assess the methodologic quality of included studies. A meta-analysis was conducted using an inverse variance-weighted random-effects model to compare the ILT volume in ruptured and asymptomatic intact AAAs. Leave-one-out sensitivity analyses were conducted to assess the robustness of the findings. A subanalysis was performed including studies in which patients with asymptomatic intact and ruptured AAAs were matched for aortic diameter. Interstudy heterogeneity was assessed using the IEight studies involving 672 patients were included in this systematic review. Meta-analysis of all studies found a greater ILT volume in patients with ruptured AAAs than in patients with asymptomatic intact AAAs (standardized mean difference, 0.56; 95% confidence interval, 0.17-0.96; P = .005; IThis meta-analysis suggests that ILT volume is greater in patients with ruptured AAAs than in patients with asymptomatic intact AAAs, although this is most likely due to the larger diameter of ruptured AAAs.

Similar to open surgical repair, thoracic endovascular aortic repair (TEVAR) carries a risk of spinal cord ischemia (SCI). However, the generally lower incidence of SCI after TEVAR compared with that after open surgical repair, despite the inability to preserve the intercostal arteries, indicates different pathophysiologic mechanisms with the two procedures. We hypothesized that a microembolism from an aortic mural thrombus is the main cause of SCI. Thus, we evaluated the association between the density of a mural thrombus in the descending thoracic aorta and the development of SCI.A retrospective review of a prospectively assembled database was performed for all patients who had undergone surgery at a single institution from October 2008 to December 2018. Patient demographics and procedure-related variables were collected. The volume and Hounsfield unit (HU) value of mural thrombi in the whole descending thoracic aorta were estimated on preoperative computed tomography using a three-dimensional workstation. Logistic regression analysis was performed to identify the risk factors for SCI development.Of the 367 patients who had undergone TEVAR during the study period, 155 were excluded because of previous arch surgery (n = 59), previous descending thoracic aortic surgery (n = 6), previous TEVAR (n = 6), unavailability of optimal preoperative computed tomography data (n = 17), double-barreled dissection (n = 40), and other reasons. The mean ± standard deviation age of the remaining 212 patients was 75.8 ± 6.4 years, and 42 (19.8%) were women. Of the 212 patients, 14 (6.6%) developed SCI after TEVAR. The low mean density of the mural thrombus, total thrombus volume, low-density (≥-100 HU but 30 HU) thrombus volume, intermediate-density (≥30 HU but 150 HU) thrombus volume, treatment length, urgent surgery, and baseline dialysis differed significantly between patients with and without SCI. Although subsequent multivariate analysis could not be performed owing to the small number of SCI events, vulnerable low-density thrombus/plaque was a stronger predictor among the aneurysm-related factors of SCI after TEVAR on univariate analysis. Well-known risk factors, such as distal coverage between T8 and L1, left subclavian artery coverage, previous abdominal aortic surgery, and prophylactic spinal drainage, did not show significant differences.The results from the present study have demonstrated that among aneurysm-related factors, a lower density mural thrombus/plaque in the descending thoracic aorta is a predictor of SCI development after TEVAR. These results suggest that microembolism is one of the important mechanisms of SCI after TEVAR, which might change the prophylactic strategy.

When the intercostal and lumbar arteries are occluded by plaque or thrombus, spinal cord perfusion depends on collateral circulation. Some reports have demonstrated collateral circulation to the artery of Adamkiewicz via computed tomography and magnetic resonance angiographies. However, intraspinal collateral circulation to the artery of Adamkiewicz along the spinal cord has not been reported previously. Here, we report two patients with intraspinal collateral circulation to the artery of Adamkiewicz along the spinal cord that was detected with intra-arterial injected computed tomography angiography.

Objective Hostile infrarenal neck characteristics are associated with complications such as type Ia endoleak after endovascular aneurysm repair. Aortic neck angulation has been identified as one such characteristic, but its association with complications has not been uniform between studies. Neck angulation assumes triangular oversimplification of the aortic trajectory, which may explain conflicting findings. By contrast, aortic curvature is a measurement that includes the bending rate and tortuosity and may provide better predictive value for neck complications. Methods Data were retrieved from the Heli-FX (Aptus Endosystems, Inc, Sunnyvale, Calif) Aortic Securement System Global Registry (ANCHOR). One cohort included patients who presented with intraoperative endoleak type Ia at the completion angiogram as the indication for EndoAnchors (Aptus Endosystems), and a second cohort comprised those without intraoperative or late type Ia endoleak (controls). The aortic trajectory was divided into six segments with potentially different influence on the stent graft performance: suprarenal, juxtarenal, and infrarenal aortic neck (−30 to −10 mm, −10 to 10 mm, and 10-30 mm from the lowest renal artery, respectively), the entire aortic neck, aneurysm sac, and terminal aorta (20 mm above the bifurcation to the bifurcation). Maximum and average curvature were automatically calculated over the six segments by proprietary custom software. Aortic curvature was compared with other standard neck characteristics, including neck length, neck diameter, maximum aneurysm sac diameter, neck thrombus and calcium thickness and circumference, suprarenal angulation, infrarenal angulation, and the neck tortuosity index. Independent risk factors for intraoperative type Ia endoleak were identified using backwards stepwise logistic regression. For the variables in the final regression model, suitable cutoff values in relation to the prediction of acute type Ia endoleak were defined with the area under the receiver operating characteristic curve. Results The analysis included 64 patients with intraoperative type Ia endoleak and 79 controls. Logistic regression identified only aortic neck calcification and aortic curvature, expressed over the juxtarenal aortic neck, the aneurysm sac, and the terminal aorta, as independent predictors of intraoperative type Ia endoleak. Conclusions Together with aortic neck calcification, aortic curvature appears to be the best predictor of intraoperative type Ia endoleak, as expressed within the juxtarenal aortic neck, the aneurysm sac, and the terminal aorta. Aortic neck angulation was not a predictor for acute failure. Aortic curvature may provide a better anatomic characteristic to define patients at risk for early complications after endovascular aneurysm repair.

Objective The purpose of this study was to report the updated results of a prospective, multicenter, nonrandomized, single-arm investigational device exemption study conducted at 17 sites in the United States to assess safety and effectiveness of the Zenith Alpha thoracic endovascular graft (Cook Medical, Bloomington, Ind) for treatment of blunt thoracic aortic injury (BTAI). Methods The primary safety end point was 30-day all-cause mortality and aortic injury-related mortality. The primary effectiveness end point was 30-day device success. Additional outcomes evaluated included major adverse events and imaging findings including aortic injury healing, graft patency, and device integrity as analyzed by the core laboratory on follow-up computed tomography imaging through 5 years. Results A total of 50 patients with BTAI were enrolled in the TRANSFIX study between January 2013 and May 2014. Mean follow-up was 21 months (range, 0.6-35 months). The 30-day mortality was 2% (n = 1), and it was unrelated to the aortic repair or study device. Five deaths occurred after 30 days, and one was considered procedure related. Freedom from all-cause and BTAI-related mortality was 89.3% and 97.6%, respectively, at 2 years. Aortic injury healing was noted in 96% at 2 years. An incidental finding of thrombus formation within the stent graft, most commonly at the distal aspect of the study device, occurred in 15 patients (30%; 12 by core laboratory, 3 by site) and was confirmed in 13 patients (26%). None of these patients were noted to have clinical sequelae on most recent follow-up. Conclusions The updated results from the TRANSFIX study continue to show low rates of aortic injury-related mortality and major adverse events during follow-up. However, findings of in-graft thrombus have resulted in the manufacturer's voluntary removal of the BTAI indication for this device. Caution should be exercised in appropriate and accurate device sizing and planning (eg, limiting graft oversizing) as well as in regular, lifelong follow-up evaluation.

Objective: Endograft mural thrombus has been associated with stent graft or limb thrombosis after endovascular aneurysm repair (EVAR). This study aimed to identify clinical and morphologic determinants of endograft mural thrombus accumulation and its influence on thromboembolic events after EVAR. Methods: A prospectively maintained database of patients treated by EVAR at a tertiary institution from 2000 to 2012 was analyzed. Patients treated for degenerative infrarenal abdominal aortic aneurysms and with available imaging for thrombus analysis were considered. All measurements were performed on three-dimensional center-lumen line computed tomography angiography (CTA) reconstructions. Patients with thrombus accumulation within the endograft's main body with a thickness >2 mm and an extension >25% of the main body's circumference were included in the study group and compared with a control group that included all remaining patients. Clinical and morphologic variables were assessed for association with significant thrombus accumulation within the endograft's main body by multivariate regression analysis. Estimates for freedom from thromboembolic events were obtained by Kaplan-Meier plots. Results: Sixty-eight patients (16.4%) presented with endograft mural thrombus. Median follow-up time was 3.54 years (interquartile range, 1.99-5.47 years). In-graft mural thrombus was identified on 30-day CTA in 22 patients (32.4% of the study group), on 6-month CTA in 8 patients (11.8%), and on 1-year CTA in 17 patients (25%). Intraprosthetic thrombus progressively accumulated during the study period in 40 patients of the study group (55.8%). Overall, 17 patients (4.1%) presented with endograft or limb occlusions, 3 (4.4%) in the thrombus group and 14 (4.1%) in the control group (P = .89). Thirty-one patients (7.5%) received an aortouni-iliac (AUI) endograft. Two endograft occlusions were identified among AUI devices (6.5%; overall, 0.5%). None of these patients showed thrombotic deposits in the main body, nor were any outflow abnormalities identified on the immediately preceding CTA. Estimated freedom from thromboembolic events at 5 years was 95% in both groups (P = .97). Endograft thrombus accumulation was associated with >25% proximal aneurysm neck thrombus coverage at baseline (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.1-3.3), neck length = 30 mm (OR, 2.4; 95% CI, 1.3-4.6), AUI (OR, 2.2; 95% CI, 1.8-5.5), or polyester-covered stent grafts (OR, 4.0; 95% CI, 2.2-7.3) and with main component "barrel-like" configuration (OR, 6.9; 95% CI, 1.7-28.3). Conclusions: Mural thrombus formation within the main body of the endograft is related to different endograft configurations, main body geometry, and device fabric but appears to have no association with the occurrence of thromboembolic events over time.

Acute arterial occlusions occur in high shear rate hemodynamic conditions. Arterial thrombi are platelet-rich when examined histologically compared with red blood cells in venous thrombi. Prior studies of platelet biology were not capable of accounting for the rapid kinetics and bond strengths necessary to produce occlusive thrombus under these conditions where the stasis condition of the Virchow triad is so noticeably absent. Recent experiments elucidate the unique pathway and kinetics of platelet aggregation that produce arterial occlusion. Large thrombi form from local release and conformational changes in von Willebrand factor under very high shear rates. The effect of high shear hemodynamics on thrombus growth has profound implications for the understanding of all acute thrombotic cardiovascular events as well as for vascular reconstructive techniques and vascular device design, testing, and clinical performance.

Objective The objective of the study was to report the feasibility and results of superior mesenteric artery (SMA) stenting using embolic protection devices (EPDs) to treat acute mesenteric ischemia (AMI) and chronic mesenteric ischemia (CMI). Methods A retrospective review was conducted of consecutive patients who underwent SMA stenting with EPDs from 2007 to 2016. EPDs were used selectively in patients with occlusions, severe calcification, or acute thrombus. A two-wire technique with SpiderFX 0.014-inch filter wire (Medtronic, Minneapolis, Minn) combined with a 0.018-inch wire was used to provide support and to facilitate stenting and EPD retrieval. Presence of macroscopic debris in the EPD was recorded and graded as minor (minimal debris) or major (large thrombus or plaque). End points were technical success, presence of EPD debris, embolization, early morbidity, and mortality. Results SMA stenting was performed in 179 patients, of whom 65 (36%) had EPDs. The mean age was 73 ± 11 years, and 49 were female (75%). Clinical presentation was CMI in 48 patients (74%) and AMI or acute-on-CMI in 17 (26%). Indications for EPD were severe calcification in 22 patients (34%), acute thrombus in 18 (28%), and total occlusion in 16 (25%). Bare-metal stents were used in 33 patients, covered stents in 26, and both types in 6. Adjunctive therapy included thrombolysis in seven patients, thrombectomy in four, and atherectomy in three. Technical success was 100%. There were no instances of filter retention or arterial trauma due to filter manipulation. Distal embolization was noted in four patients (6%), of whom two had AMI. All large emboli were retrieved using catheter aspiration devices, but one small distal embolus was left untreated with no clinical consequences. Two patients had vessel spasm treated by nitroglycerin. Macroscopic debris was noted in 43 patients (66%) and was major in 21 (49%) or minor in 22 (51%). Of the patients with AMI, five (29%) required exploratory laparotomy and four (23%) had bowel resection. Eight additional patients (12%) had early complications (five CMI, three AMI), including cardiac complications, brachial hematoma, acute cholecystitis, and acute respiratory distress syndrome in two patients each. There were no deaths among CMI patients and two early deaths (12%) among those who had AMI. Conclusions Use of EPDs during SMA stenting is safe and feasible with a two-wire technique. Large macroscopic debris was noted in one-third of the patients when the filter was applied selectively in patients with acute symptoms, occlusions, or severely calcified lesions. Despite the use of EPD, distal embolization occurred in 6% of patients and was successfully treated using catheter aspiration devices.

Background The Nellix System (Endologix, Inc, Irvine, Calif) for endovascular aneurysm sealing (EVAS) is a novel approach to abdominal aortic aneurysm treatment and conceptually different from endovascular aneurysm repair, whereby polymer is employed to fill and actively manage the abdominal aortic aneurysm sac. One-year safety and effectiveness results of the Nellix pivotal trial demonstrated encouraging outcomes with very low morbidity and mortality and high procedural and treatment success. Two-year imaging revealed a signal of migration, leading to a field safety notification issued by the manufacturer on October 21, 2016, and a dedicated root cause analysis, resulting in refinements to the instructions for use (IFU). We report the 2-year results of the investigational device exemption pivotal trial stratified according to the new and original criteria for selection of patients. Methods Comprehensive engineering evaluations, statistical analyses, and clinical assessments were conducted looking at patients enrolled in the pivotal trial (N = 150), roll-in cohort (N = 29), and continued access program (N = 154). All patients in all cohorts were treated on-IFU at the time of enrollment. Logistic regression models supported the mechanism that migration with Nellix is associated with a small aortic flow lumen relative to a large aneurysm thrombus burden and large aortic neck diameters. Based on these findings, refinements to the IFU criteria were applied, excluding patients with a thrombus index (maximum aneurysm sac/maximum flow lumen diameter) >1.4, aortic neck diameter >28 mm, and aortic neck conicity (>10% diameter change along the infrarenal neck) and requiring a 10-mm distal seal zone in the iliac artery. Results Freedom from all-cause mortality at 2 years was 94%. Patient outcomes were then stratified on the refined morphologic criteria and analyzed retrospectively. Two-year freedom from composite endoleak was high among both cohorts (95% on-IFU vs 92% off-IFU). Freedom from migration was 97.7% on-IFU vs 93.2% off-IFU (P = .0125). Freedom from aneurysm enlargement was 98.1% on-IFU vs 93.5% off-IFU (P value is not available because of failure of log-rank test assumptions). Composite freedom from migration, type IA endoleak, or aneurysm expansion was 95.9% among the on-IFU cohort vs 85.1% in the off-IFU cohort (P = .0017). Conclusions Consistent with the introduction of a novel therapy, the presentation of failure modes of EVAS over time was inevitable. Using detailed imaging as well as engineering and statistical analysis, we were able to understand risk factors for adverse events specific to EVAS and defined those patients best suited for Nellix. With this EVAS-specific approach to defining IFU, on-IFU patients were identified as those with large aneurysms with little thrombus that would be prone to type II endoleaks and sac expansion with traditional devices. When treated with Nellix, these patients were predicted to experience exceptional results, especially with regard to a low composite endoleak rate and low all-cause mortality.

Objective The objective of this study was to examine whether prophylactic use of EndoAnchors (Medtronic, Santa Rosa, Calif) contributes to improved outcomes after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms through 2 years. Methods The Aneurysm Treatment Using the Heli-FX Aortic Securement System Global Registry (ANCHOR) subjects who received prophylactic EndoAnchors during EVAR were considered for this analysis. Imaging data of retrospective subjects who underwent EVAR at ANCHOR enrolling institutions were obtained to create a control sample. Nineteen baseline anatomic measurements were used to perform propensity score matching, yielding 99 matched pairs. Follow-up imaging of the ANCHOR and control cohorts was then compared to examine outcomes through 2 years, using Kaplan-Meier survival analysis. Results Freedom from type Ia endoleak was 97.0% ± 2.1% in the ANCHOR cohort and 94.1% ± 2.5% in the control cohort through 2 years ( P = .34). The 2-year freedom from neck dilation in the ANCHOR and control cohorts was 90.4% ± 5.6% and 87.3% ± 4.3%, respectively ( P = .46); 2-year freedom from sac enlargement was 97.0% ± 2.1% and 94.0% ± 3.0%, respectively ( P = .67). No device migration was observed. Aneurysm sac regression was observed in 81.1% ± 9.5% of ANCHOR subjects through 2 years compared with 48.7% ± 5.9% of control subjects ( P = .01). Cox regression analysis found an inverse correlation between number of hostile neck criteria met and later sac regression ( P = .05). Preoperative neck thrombus circumference and infrarenal diameter were also variables associated with later sac regression, although not to a significant degree ( P = .10 and P = .06, respectively). Control subjects with thrombus were significantly less likely to experience later sac regression than those without thrombus (6% and 43%, respectively; P = .001). In ANCHOR subjects, rate of regression was not significantly different in subjects with or without thrombus (33% and 36%, respectively; P = .82). Control subjects with wide aortic necks (>28 mm) were observed to experience sac regression at a lower rate than subjects with smaller diameter necks (10% and 44%, respectively; P = .004). Wide neck and normal neck subjects implanted with EndoAnchors experienced later sac regression at roughly equivalent rates (44% and 33%, respectively; P = .50). Conclusions In propensity-matched cohorts of subjects undergoing EVAR, the rate of sac regression in subjects treated with EndoAnchors was significantly higher. EndoAnchors may mitigate the adverse effect of wide infrarenal necks and neck thrombus on sac regression, although further studies are needed to evaluate the long-term effect of EndoAnchors.

The ideal treatment option for patients with complex aneurysm morphology remains highly debated. The aim of this study was to investigate the impact of endovascular aneurysm repair (EVAR) with active fixation on outcomes in patients with complex aneurysm morphology.There were 340 consecutive patients who underwent EVAR using active fixation devices, 234 with active infrarenal fixation (AIF; Gore Excluder; W. L. GoreAssociates, Flagstaff, Ariz) and 106 with active suprarenal fixation (ASF; 85 Medtronic Endurant [Medtronic, Santa Rosa, Calif] and 21 Cook Zenith [Cook Medical, Bloomington, Ind]). Demographics, comorbidities, anatomic features, and outcomes were analyzed for patients receiving devices with active fixation. Outcomes of using active fixation in necks with 15-mm neck lengths,60-degree infrarenal neck angle (β),30-mm infrarenal neck diameter, severe aortic neck calcification or thrombus, and nonstraight neck morphology were evaluated.Of the 340 patients, 106 (78 men; mean age, 74.5 ± 9.3 years at the time of surgery) received implants with ASF and 234 (191 men; mean age, 74.6 ± 8.9 years at the time of surgery) received implants with AIF. In comparing AIF and ASF devices, patients in the suprarenal fixation group had significantly shorter follow-up time (25 ± 17 months vs 44.3 ± 32 months; P .0001). Patients in the ASF group had shorter aortic neck lengths (25.5 ± 15.1 mm vs 28.6 ± 14.9 mm; P = NS) and significantly larger infrarenal neck diameters (25.9 ± 6.3 mm vs 23.4 ± 3.2 mm; P .0001) and aneurysm diameters (59.9 ± 11.6 mm v. 55.9 ± 10.0 mm; P = .002). Outcomes were similar between groups, with no significant differences in reintervention, proximal endoleak, sac growth, abdominal aortic aneurysm-related death, or rupture. Of the complex anatomic neck features investigated, neck diameter30 mm and nonstraight neck morphology had the highest rates of reintervention in ASF devices.In cases of hostile infrarenal neck morphology, ASF appears to be used more frequently. Our data suggest that ASF may be useful for certain patients but may be unfavorable for others, such as those with wide necks or several difficult neck features. Nevertheless, further research is needed to evaluate more optimal treatment options, such as fenestrated EVAR, branched EVAR, and endovascular adjuncts such as EndoAnchors (Aptus Endosystems, Sunnyvale, Calif), in dealing with high-risk anatomic characteristics that may not be optimally managed with standard EVAR devices with active fixation.

The objective of this study was to determine the natural progression of popliteal artery aneurysms (PAAs) and clinical variables associated with their accelerated growth.Retrospective chart review of 224 patients with encounters between January 2008 and May 2016 and with at least one PAA was conducted. From this group, 65 asymptomatic patients had either unilateral (n = 43) or bilateral (n = 22) PAAs that were observed for at least 1 year of medical management before intervention. We divided these aneurysms into two groups based on whether their overall growth rate was above or below the eventual mean. Aneurysm diameter was taken from duplex ultrasound and computed tomography angiography.There were 87 aneurysms evaluated among 65 patients. Mean age at diagnosis was 70.9 years (standard deviation [SD], 9.39 years), and 64 patients were male (98%); 50 (77%) were white and 7 (11%) were African American. The average body mass index was 27.69 (SD, 4.90). At or before initial diagnosis, 61 (94%) patients had a concomitant lower extremity or abdominal aortic aneurysm; 51 (78%) patients were current or former smokers; and 16 (25%) had atrial fibrillation. The average growth rate of all aneurysms was 1.22 mm/y (SD, 1.93 mm). The mean surveillance time from initial diagnosis to last follow-up or intervention was 3.12 years (SD, 1.66 years). Of 87 aneurysms, 25 (29%) were repaired; 18 (21%) were repaired because of size criteria, 2 (2%) because of symptom criteria (claudication or acute limb ischemia), and 5 (6%) because of both criteria. During our study window, 62 aneurysms (71%) remained asymptomatic or did not undergo an intervention. The mean initial diameter at diagnosis was 16.9 mm (SD, 5.32 mm). Within the study, 50 (57%) aneurysms presented with or developed mural thrombus. Univariate analysis identified larger initial diameter (19.2 vs 14.7 mm; P = .020), atrial fibrillation (35% vs 16%; P = .042), and mural thrombus (38% vs 20%; P .001) as predictors of diameter expansion greater than the mean. Multivariable analysis of the significant univariate factors determined that only initial diameter (odds ratio, 5.53; P = .007) and the presence or development of mural thrombus (odds ratio, 4.00; P = .008) maintained significance.Patients presenting with a PAA at 20 mm or20 mm in diameter, presence of luminal thrombus, or atrial fibrillation may need to be observed at more frequent scanning intervals than those without these risk factors. Further studies are required to validate these predictive growth factors.

Objective Increasing data supports the role of bacterial inflammation in adverse events of cardiovascular and cerebrovascular diseases. In our previous research, DNA of bacterial species found in coronary artery thrombus aspirates and ruptured cerebral aneurysms were mostly of endodontic and periodontal origin, where Streptococcus mitis group DNA was the most common. We hypothesized that the genomes of S mitis group could be identified in thrombus aspirates of patients with lower limb arterial and deep venous thrombosis. Methods Thrombus aspirates and control blood samples taken from 42 patients with acute or acute-on-chronic lower limb ischemia (Rutherford I-IIb) owing to arterial or graft thrombosis (n = 31) or lower limb deep venous thrombosis (n = 11) were examined using a quantitative real-time polymerase chain reaction to detect all possible bacterial DNA and DNA of S mitis group in particular. The samples were considered positive, if the amount of bacterial DNA in the thrombus aspirates was 2-fold or greater in comparison with control blood samples. Results In the positive samples the mean difference for the total bacterial DNA was 12.1-fold (median, 7.1), whereas the differences for S mitis group DNA were a mean of 29.1 and a median of 5.2-fold. Of the arterial thrombus aspirates, 57.9% were positive for bacterial DNA, whereas bacterial genomes were found in 75% of bypass graft thrombosis with 77.8% of the prosthetic grafts being positive. Of the deep vein thrombus aspirates, 45.5% contained bacterial genomes. Most (80%) of bacterial DNA-positive cases contained DNA from the S mitis group. Previous arterial interventions were significantly associated with the occurrence of S mitis group DNA ( P = .049, Fisher's exact test). Conclusions This is the first study to report the presence of bacterial DNA, predominantly of S mitis group origin, in the thrombus aspirates of surgical patients with lower limb arterial and deep venous thrombosis, suggesting their possible role in the pathogenesis of thrombotic events. Additional studies will, however, be needed to reach a final conclusion.

ObjectiveThe objective of this study was to evaluate the impact of contrast medium volume, inferior mesenteric artery (IMA) patency, and pre-existing as well as new-onset thrombus on the inflammatory response after elective endovascular aneurysm repair (EVAR).MethodsThe study included 87 patients undergoing elective endovascular repair of asymptomatic infrarenal aneurysms between January 2011 and November 2011. The patency of the IMA was determined by preoperative computed tomography angiography; the volume of the contrast medium used during the procedure was measured, and the volumes of chronic mural as well as new-onset thrombus were calculated from the preoperative and postoperative computed tomography angiograms with dedicated imaging software. The results were correlated to the occurrence of postimplantation syndrome (PIS) as well as to the main clinical and laboratory components of PIS: fever; increased white blood cell (WBC) count and C-reactive protein (CRP) level; decreased platelet count; and increased interleukin (IL)-6, IL-8, and IL-10 levels.ResultsPostoperatively, a statistically significant increase was recorded in the mean values of body temperature, WBCs, CRP, IL-6, IL-8, and IL-10, and a statistically significant decrease was recorded in the number of platelets. After adjustment for endograft type, the volume of new-onset thrombus was found to be significantly correlated with the peak postoperative temperature (β = .307; P < .05) and the increase in WBC count (β = .271; P < .05), CRP level (β = .484; P

ObjectiveIn this study we aimed to report on the midterm outcome of multiple overlapping uncovered stents in the treatment of peripheral and visceral aneurysms, and analyze the possible factors affecting the treatment efficacy.MethodsData of patients who were regularly followed up over 24 months were retrospectively reviewed. Descriptive statistics were applied to present aneurysm thrombosis process and diameter change at each follow-up point, and a comparison with the baseline level was performed. Patients were divided into a totally thrombosed (TT) group and a residual perfusion (RP) group according to the sac thrombosis ratio (thrombus volume to sac volume ratio) at 3, 6, and 12 months of follow-up. Aneurysm shrinkage in the two groups was compared to explore the effect of the initial RP on the treatment outcome. Patients were also grouped based on their aneurysm morphology (saccular/fusiform). The aneurysm sac thrombosis speed (time to thrombosis) and diameter decrease (DD) ratio (percentage of DD) were compared between the two groups to understand the influence of aneurysm shape on the treatment efficacy.ResultsOf the 64 patients treated, the initial 37 patients (25 male; average age, 55.5 ± 13.0 years) were enrolled into this study. Technical success rate was 100%. All patients were regularly followed up. At 24 months, 94.6% aneurysms (35/37) were TT, and the maximum aneurysm diameter decreased from 36.5 ± 9.7 mm preoperatively to 23.6 ± 7.7 mm (P < .001). Overall clinical success rate (complete thrombosis and shrinkage/stabilization of the aneurysm without aneurysm-related mortality) reached 94.6% in the study cohort. Most side branches (31/33) covered by the bare stent stayed patent during follow-up. Initial sac RP at 3, 6, and 12 months might not fully affect the final aneurysm DD ratio (TT group: 0.37 ± 0.09, 0.35 ± 0.09, and 0.35 ± 0.09; compared with the RP group: 0.33 ± 0.09, 0.36 ± 0.11, and 0.36 ± 0.13; P = .153, .964, and .418, respectively). At 3 and 6 months follow-up, saccular aneurysms (n = 29) seemed to have a faster thrombosis speed compared with fusiform aneurysms (78.1 ± 26.8% and 83.9 ± 21.8% vs 47.0 ± 24.4% and 63.9 ± 22.6%; P = .004 and .013, respectively), but there was no significant difference in aneurysm shrinkage ratio at 24 months between the two groups (0.36 ± 0.10 vs 0.33 ± 0.06; P = .357).ConclusionsMultiple overlapping uncovered stents could be a feasible option for the endovascular treatment of peripheral and visceral aneurysms. Neither the aneurysm shape nor the initial sac RP would affect the midterm treatment outcome. Further validation of this technique is required to substantiate these results.

Objective Most abdominal aortic aneurysms (AAAs) contain intraluminal thrombus (ILT), which has been demonstrated to contain proteolytic enzymes and proinflammatory cytokines implicated in AAA progression and rupture. In animal models, anticoagulants have been shown to limit AAA progression. Whether ILT plays a role in AAA rupture is unknown. The aim of this study was to compare the volume of ILT in patients with ruptured and intact AAAs. Methods We matched by maximum axial diameter alone, on a 1:2 basis, 28 patients with ruptured AAAs and 56 patients with intact AAAs. Total infrarenal aortic volume and ILT volume were measured from computed tomography angiograms using a previously validated and reproducible semiautomated workstation protocol. Clinical risk factors were also recorded. The Mann-Whitney U test was used to compare ILT volumes between patients with ruptured and intact AAAs. Results Median (interquartile range [IQR]) maximum AAA diameter (84.0 [77.5-93.9] mm vs 82.6 [77.1-93.3] mm; P = .769) and median (IQR) total AAA volume (372.8 [277.4-486.1] cm 3 vs 358.4 [289.1-563.4] cm 3 ; P = .977) were similar in patients with ruptured and intact AAAs. Median (IQR) AAA ILT volume was similar in patients with ruptured (152.7 [84.8-252.4] cm 3 ) and intact (180.1 [89.9-254.8] cm 3 ; P = .414) AAAs. Conclusions This study suggests that ILT volume is not different in ruptured and intact AAAs.

Objective Although the management of carotid disease is well established for symptomatic lesions ≥70%, the surgical treatment for a symptomatic ≤50% stenosis is not supported by data from randomized trials. Factors other than lumen narrowing, such as plaque instability, seem to be involved in cerebral and retinal ischemic events. This study analyzes the early-term and long-term outcomes of carotid endarterectomy (CEA) performed in patients with low-grade (≤50% on North American Symptomatic Carotid Endarterectomy Trial criteria) symptomatic carotid stenosis. Methods The study involves 57 consecutive patients undergoing CEA for symptomatic low-grade carotid disease at our institution over 5 years, and 21 (36.8%) had experienced more than one ischemic event. Overall, 48 (84.2%) had a minor stroke, and nine (15.8%) had an episode of retinal ischemia. Diagnosis was made by a vascular neurologist based on an ultrasound examination combined with noninvasive imaging studies, after ruling out other possible causes of embolization. Before CEA, all patients were receiving antiplatelet treatment, and 87% were taking statins. All patients underwent eversion CEA under general deep anesthesia, with selective shunting. All carotid plaques were examined histologically. Long-term follow-up (median, 28 months; mean, 32 ± 5 months; range, 3-56 months) was obtained for 55 patients. Results No 30-day strokes or deaths occurred, and no patients had recurrent neurologic events related to the revascularized hemisphere during the follow-up. No late carotid occlusions were detected, but one asymptomatic moderate restenosis was documented. There were seven late deaths (12.7%), none of which were stroke-related. Survival rates were 98% at 1 year and 90% at 3 years. All removed carotid plaques showed different features of ulceration or rupture, with underlying hemorrhage associated with a thrombus. Conclusions This study shows that CEA is a safe, effective, and durable treatment for patients with symptomatic low-grade carotid stenosis associated with unstable plaque. Patients had excellent protection against further ischemic events and survived long enough to justify the initial surgical risk. Plaque instability seems to play a major part in the onset of ischemic events, regardless the entity of lumen narrowing.

ObjectiveIn patients undergoing endovascular aneurysm repair (EVAR), the postimplantation syndrome (PIS), comprising fever and inflammation, occurs frequently. The cause of PIS is unclear, but graft composition and acute thrombus formation may play a role. The objective of this study was to evaluate these possible causes of the inflammatory response after EVAR.MethodsOne hundred forty-nine patients undergoing elective EVAR were included. Implanted stent grafts differed mainly in the type of fabric used: either woven polyester (n = 82) or expanded polytetrafluorethylene (ePTFE; n = 67). Tympanic temperature and C-reactive protein (CRP) were assessed daily during hospitalization. PIS was defined as the composite of a body temperature of ≥38°C coinciding with CRP >10 mg/L. Besides graft composition, the size of the grafts and the volume of new-onset thrombus were calculated using dedicated software, and results were correlated to PIS.ResultsImplantation of grafts made of polyester was associated with higher postoperative temperature (P < .001), CRP levels (P < .001), and incidence of PIS (56.1% vs 17.9%; P < .001) compared to ePFTE. After multivariate analysis, woven polyester stent grafts were independently associated with an increased risk of PIS (hazard ratio, 5.6; 95% confidence interval, 1.6-19.4; P = .007). Demographics, amount of graft material implanted, or new-onset thrombus had no association with PIS.ConclusionsThe composition of stent grafts may play a material role in the incidence of postimplantation syndrome in patients undergoing EVAR. Implantation of stent grafts based on woven polyester was independently associated with a stronger inflammatory response.

Objective Percutaneous mechanical thrombectomy (PMT) is regularly used in the treatment of both venous and arterial thrombosis. Although there has been no formal report, PMT has been linked to cases of reversible postoperative acute kidney injury (AKI). The purpose of this study is to evaluate the risk of renal dysfunction in patients undergoing PMT vs catheter-directed thrombolysis (CDT) for treatment of an acute thrombus. Methods This study is a retrospective review of all patients in a single institution with a Current Procedural Terminology code for PMT or CDT from January 2009 through December 2014. Each patient was grouped into one of the four following procedural categories: PMT only, PMT with tissue plasminogen activator (tPA) pulse-spray, PMT with CDT, or CDT only. Preoperative and postoperative creatinine and glomerular filtration rate (GFR) values were obtained for each patient. The RIFLE (Risk, Injury, Failure, Loss, and End-stage renal disease) criteria were used to categorize the extent of renal dysfunction. χ 2 analysis, one-way analysis of variance, and unpaired t -test were used to assess significance. Results A total of 227 patients were reviewed, of which 82 were excluded due to either existence of preoperative AKI, history of end-stage renal disease, or lack of clinical data. Of the remaining 145 patients, 53 (37%) presented with arterial thrombosis (mean age, 62 years; 43% male) and 92 (63%) presented with venous thrombosis (mean age, 48 years; 45% male). The incidence of renal dysfunction was highest in the PMT/tPA pulse group (21%), followed by the PMT group (20%) and the PMT/CDT group (14%). CDT was not associated with renal dysfunction. PMT ( P = .046), and PMT/tPA pulse ( P = .033) were associated with higher rates of renal dysfunction than the CDT controls. The average preoperative GFR for the 22 patients who developed AKI was 53.7 ± 9.4 mL/min/1.73 m 2 . The minimum postoperative GFR within 48 hours was an average of 35 ± 16 mL/min/1.73 m 2 . Stratified by the RIFLE criteria, 13 (9%) patients progressed to the risk category, 6 (4%) progressed to the injury category, and 3 (2%) progressed to the failure category. None of the patients who developed renal dysfunction from PMT progressed to dialysis within the same admission period. Conclusions The use of PMT as a treatment for vascular thrombosis is associated with renal dysfunction. Patients treated with PMT require postoperative vigilance and renal protective measures.

International audience; BACKGROUND: Aneurysmal regression is a reliable marker for long-lasting success after endovascular aneurysm repair (EVAR). The aim of this study was to identify the preoperative factors that can predictably lead to aneurysmal sac regression after EVAR, according to the reporting standards of the Society for Vascular Surgery and the International Society of Cardiovascular Surgery (SVS/ISCVS). METHODS: From 199 patients treated by EVAR between 2000 and 2009, 164 completed computed tomography angiographies and duplex scan follow-up images were available. All computed tomography angiographies for enrolled patients in this retrospective study were analyzed with Endosize software (Therenva, Rennes, France) to provide spatially correct 3-dimensional data in accordance with SVS/ISCVS recommendations. Anatomic parameters were graded according to the relevant severity grades. A severity score was calculated at the aortic neck, the abdominal aortic aneurysm, and the iliac arteries. Clinical and demographic factors were studied. Patients with aneurysmal regression >5 mm were assigned to group A (mean age, 71.4 ± 8.9 years) and the others to group B (76.3 ± 8.3 years). RESULTS: Aneurysmal regression occurred in 66 patients (40.2%; group A). Univariate analyses showed smaller severity scores at the aortic neck (P = .02) and the iliac arteries (P = .002) in group A and calcifications and thrombus were less significant at the aortic neck (P = .003 and P = .02) and at the iliac arteries (P = .001 and P = .02), and inferior mesenteric artery patency was less frequent (68.2% vs 82.7%, P = .04). Two multivariate analyses were done: one considered the scores and the other the variables included in the scores. In the first, the patients of group A were younger (P = .002) and aortic neck calcifications were less significant (P = .007). In the second, group A patients were younger (P < .001) and the aortic neck scores were smaller (P = .04). There was no difference between the two groups in the type of implanted endoprosthesis or in the follow-up (group A: 46.4 ± 24 months; group B: 47.2 ± 22 months; P = .35). CONCLUSIONS: In this study, the young age of the patients and their aortic neck quality, in particular the absence of neck calcification, appear to have been the main factors affecting aneurysm shrinkage, such that they represent a target population for the improvement of EVAR results.

BackgroundHyperlipidemia increases the level of blood plasminogen activator inhibitor-1 (PAI-1) that is responsible for regulating fibrinolysis by inhibiting both urokinase-type plasminogen activator (u-PA) and tissue-type plasminogen activator (t-PA). While this fibrinolytic pathway is well known, the role of PAI-1 in venous thrombosis (VT) under hyperlipidemic conditions has not been fully established. We sought to determine the effects of PAI-1 in an in vivo hyperlipidemic model of VT.MethodsC57BL/6 wild-type (WT) mice, apolipoprotein E gene-deleted mice (ApoE-/-) having hyperlipidemia, and PAI-1 gene-deleted (PAI-1-/-) mice were used in this study. Inferior vena cava (IVC) ligation below the level of the renal veins was performed to create a stasis VT. Endpoints included measuring acute thrombosis (day 2) and chronic thrombosis (days 6 and 14). At euthanasia, blood samples were collected for plasmin and PAI-1 activity. In addition, the IVC and its thrombus were evaluated for thrombus weight (TW), u-PA activity, and differential leukocyte count while the vein wall only was analyzed for monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinase (MMP) 2, and MMP-9.ResultsCompared to WT at day 2, ApoE-/-mice demonstrated a statistically significant 14% increase in TW (P < .05) and a significant 41% increase in circulating PAI-1 activity (P < .05), while showing a trend of decreased plasmin activity. In addition, TW in ApoE-/-mice was 45% higher than PAI-1-/-mice at day 2 (P < .05), 33% at day 6 (P < .01), and 41% at day 14 (P < .01). ApoE-/-mice exhibited undetectable levels of u-PA in both vein wall and thrombus, compared to WT, at all time points. Also, vein wall MMP-2 was significantly decreased by 64% at day 6 (P < .01) and 58% at day 14 (P < .05). MMP-9 was significantly decreased by 71% at day 2 (P < .01) and 48% at day 6 (P < .01), in ApoE-/-mice compared to WT mice. In addition, in ApoE-/-mice, MCP-1 was significantly decreased by 38% at day 2 (P < .01) and 67% at day 6 (P < .01) vs WT mice. As expected in ApoE mice, following a decrease in MCP-1, monocyte recruitment was significantly decreased at days 6 (P < .01) and 14 (P < .05).ConclusionsA significant increase of circulating PAI-1 levels in hyperlipidemic mice correlated with an early increase in TW due to impaired fibrinolysis. The undetectable levels of u-PA in ApoE-/-mice correlated to a decrease in vein wall MMP-2, MMP-9, MCP-1, and a decrease in monocyte recruitment diminishing thrombus resolution.Clinical RelevanceRecent studies have presented evidence of a connection between hyperlipidemia and deep vein thrombosis (DVT). Here we present our findings on characterizing a mouse model of DVT in hyperlipidemia. We found a dysfunction in the fibrinolytic system in hyperlipidemic mice undergoing venous thrombosis. This information may contribute to a better understanding of the mechanisms linking hyperlipidemia and DVT. In addition, we believe that our findings represent a solid characterization of a mouse model for future therapeutic studies involving DVT and hyperlipidemia.

Background Iliofemoral deep vein thrombosis (DVT) is associated with severe postthrombotic morbidity when treated with anticoagulation alone. Catheter-directed thrombolysis (CDT), with or without the addition of mechanical techniques, is increasingly recommended for patients with iliofemoral DVT, although its effect on postthrombotic syndrome is not established. This study examined the correlation of residual thrombus with postthrombotic syndrome after catheter-based attempts at thrombus removal in patients with iliofemoral DVT. Methods Seventy-one consecutive patients with iliofemoral DVT were treated with CDT. Pretreatment and posttreatment phlebograms were evaluated for quantity of residual thrombus by physicians blinded to clinical patient outcomes. Postthrombotic syndrome was assessed using CEAP and Villalta scores by examiners blinded to phlebographic results. Patients were grouped by the amount of residual thrombus in treated vein segments (group 1, ≤50%; group 2, >50%). Clinical score and postthrombotic outcomes were plotted vs residual thrombus. Results Sixty-three of 71 patients completed CEAP and Villalta analyses. Groups 1 and 2 had median CEAP scores of 1 and 4 ( P = .025) and mean Villalta scores of 2.21 and 7.13, respectively ( P = .011). There was a direct and significant correlation of clinical class of CEAP with residual thrombus ( R 2 = .74 ; P = .004 ) and a direct linear correlation of Villalta score with residual thrombus ( R 2 = .61; P=.0014 ). Conclusions In patients with iliofemoral DVT treated with catheter-based techniques of thrombus removal, postthrombotic morbidity is related to residual thrombus. When thrombus clearance was complete, the postthrombotic syndrome was avoided. Residual thrombus is associated with an increasing risk of postthrombotic syndrome.