Branch Thrombus after Endovascular Treatment with Arch Branched Devices for Aortic Arch Pathologies.

OBJECTIVE: The aim of this study was to describe the occurrence of branch thrombosis following endovascular treatment of aortic arch pathology using an arch branched device (ABD) and to determine whether this is influenced by clinical and geometric parameters. METHODS: In this retrospective observational study of patients treated with an ABD in three centres, the primary endpoint was thrombus formation within a branch during follow up. Secondary endpoints were technical success, serious adverse events (SAEs), early and late death, stroke, and re-interventions. Geometric measurements (tortuosity index and curvature) were determined on pre- and post-operative computed tomography angiograms. RESULTS: Thirty nine patients were treated and 68 antegrade branches were analysed (innominate artery, n = 27; common carotid artery [CCA], n = 40; left subclavian artery [LSA], n = 1). Thrombus was identified within seven branches (10%) on surveillance imaging (innominate artery, n = 6; CCA, n = 1; LSA, n = 0; p = .021) and was associated with a wider distal bridging stent diameter (median 14.0 mm [13.3, 15.3] vs. 8.7 mm [IQR 5.9]; p = .026), a higher degree of reversed tapering (4.3 mm [3.8, 5.2] vs. 1.2 mm [0.3, 3.1]; p = .023), use of polyethylene terephthalate (Dacron) covered (vs. expanded polytetrafluoroethylene) bridging stents (23% vs. 2%; p = .011), and higher body mass index (BMI) (32.1 kg/m2 [28.7, 36.2] vs. 25.7 kg/m2 [23.8, 29.2]; p = .029), but not with pre-operative or post-operative tortuosity index or curvature or alterations. Regarding secondary outcomes, the technical success rate was 97%, SAEs occurred in 15 patients (38%), early and late death rates were 8% and 23%, respectively, and early and late stroke rates were 5% and 23%, respectively. CONCLUSION: The risk of developing branch thrombosis after endovascular intervention with an ABD is considerable, especially of innominate artery branches, characterised by Dacron covered large diameter bridging stents, and in patients with a high BMI. Large prospective studies are required to analyse factors associated with branch thrombosis.

European Multicentric Experience With Fenestrated-branched ENDOvascular Stent Grafting After Previous FAILed Infrarenal Aortic Repair: The EU-FBENDO-FAIL Registry.

OBJECTIVE: To report the mid-term outcomes of fenestrated-branched endovascular aneurysm repair (F-BEVAR) following a failed previous endovascular aneurysm repair (pEVAR) or previous open aneurysm repair (pOAR). METHODS: Data from consecutive patients who underwent F-BEVAR for pEVAR or pOAR from 2006 to 2021 from 17 European vascular centers were analyzed. Endpoints included technical success, major adverse events, 30-day mortality, and 5-year estimates of survival, target vessel primary patency, freedom from reinterventions, type I/III endoleaks, and sac growth >5 mm. BACKGROUND: Treatment of a failed previous abdominal aortic aneurysm repair is a complex undertaking. F-BEVAR is becoming an increasingly attractive option, although comparative data are limited regarding associated risk factors, indications for treatment, and various outcomes. RESULTS: There were 526 patients included, 268 pOAR and 258 pEVAR. The median time from previous repair to F-BEVAR was 7 (interquartile range, 4-12) years, 5 (3-8) for pEVAR, and 10 (6-14) for pOAR, P <0.001. Predominant indication for treatment was type Ia endoleak for pEVAR and progression of the disease for pOAR. Technical success was 92.8%, pOAR (92.2%), and pEVAR (93.4%), P =0.58. The 30-day mortality was 6.5% overall, 6.7% for pOAR, and 6.2% for pEVAR, P =0.81. There were 1853 treated target vessels with 5-year estimates of primary patency of 94.4%, pEVAR (95.2%), and pOAR (94.4%), P =0.03. Five-year estimates for freedom from type I/III endoleaks were similar between groups; freedom from reintervention was lower for pEVAR (38.3%) than for pOAR (56.0%), P =0.004. The most common indication for reinterventions was for type I/III endoleaks (37.5%). CONCLUSIONS: Repair of a failed pEVAR or pOARis safe and feasible with comparable technical success and survival rates. While successful treatment can be achieved, significant rates of reintervention should be anticipated, particularly for issues related to instability of target vessels/bridging stents.

Fenestrated/branched endovascular aortic repair using unilateral femoral access in patients with iliac occlusive disease.

OBJECTIVE: Fenestrated/branched endovascular aortic repair (F/BEVAR) in patients with occluded iliac arteries is challenging owing to limited access for branch vessel catheterization and increased risk for leg and spinal ischemic complications. The aim of this study was to analyze technical strategies and outcomes of F/BEVAR in patients with unilateral iliofemoral occlusive disease. METHODS: We performed a retrospective review of all consecutive patients treated by F/BEVAR in two institutions (2003-2021). Patients with unilateral iliofemoral occlusive disease were included in the analysis. All patients had one patent iliac artery that was used for advancement of the fenestrated-branch component. Preloaded catheter/guidewire systems or steerable sheaths were used as adjuncts to facilitate catheterization. Primary endpoints were technical success, mortality, major adverse events (stroke, spinal cord injury, dialysis or decrease in the glomerular filtration rate of more than 50%, bowel ischemia, myocardial infarction, or respiratory failure), primary iliac patency, and freedom from reinterventions. RESULTS: There were 959 patients treated with F/BEVAR. Of these, 15 patients (1.56%; mean age, 74 years; 80% male) had occluded iliac arteries and 1 patent iliofemoral access and were treated for a thoracoabdominal aortic aneurysm (n = 8) or juxtarenal abdominal aortic aneurysm (n = 7). Brachial access was used in 14 of the 15 patients and preloaded systems in 7 of the 15 patients (47%). The remaining 53% had staggered deployment of stent grafts. There were seven physician-modified endovascular grafts, seven custom-made devices, and one off-the-shelf device used. Thirteen patients (87%) had distal seal using aortouni-iliac stent grafts and two (13%) had distal seal in the infrarenal aorta. Concomitant femoral crossover bypass (FCB) was performed in two patients and six patients had a prior FCB. Technical success was 100%. There were no intraoperative complications or early lower extremity ischemic complications, and all FCB were preserved. There was one mortality (7%) within 30 days owing to retrograde type A dissection. Major adverse events occurred in 20% of patients. The median follow-up was 12 months (range, 0-85 months). Two patients (13%) required three reinterventions. One patient required proximal stent graft extension for an acute type B dissection (3 months) and another required iliac extension for type Ib endoleak of an aortouni-iliac graft (21 months) and thrombolysis of that extension (50 months). At last follow-up, all patients had primary graft patency except one with secondary graft patency without new claudication. One patient had a single renal artery stent occlusion at follow-up with no r-intervention. The overall survival rate was 60%, without aortic-related deaths. CONCLUSIONS: Although challenging, F/BEVAR with unilateral femoral/brachial approach is feasible in patients with occluded iliac limbs, with an important rate of ischemic complications, but satisfactory outcomes.

Safety of Percutaneous Femoral Access for Endovascular Aortic Aneurysm Repair Through Previously Surgically Exposed or Repaired Femoral Arteries.

OBJECTIVE: Percutaneous femoral artery access is being increasingly used in endovascular aortic repair (EVAR). The technique can be challenging in patients with previously surgically exposed or repaired femoral arteries because of excessive scar tissue. However, a successful percutaneous approach may cause less morbidity than a "re-do" open femoral approach. The aim of this study was to assess the impact of prior open surgical femoral exposure on technical success and clinical outcomes of percutaneous approach. METHODS: This study retrospectively reviewed the clinical data of patients who underwent percutaneous EVAR between 2010 and 2020 at 2 major aortic centers. Patients were divided into 2 groups (with or without prior open surgical femoral access) for analysis of clinical outcomes. Only punctures with sheaths ≥12Fr were included for analysis. The access and (pre)closure techniques were similar in both institutions. Primary end points were intraoperative technical success, access-related revision, and access complications. A multivariate analysis was performed to identify determinants of conversion to open approach and femoral access complications in intact and re-do groins. RESULTS: A total of 632 patients underwent percutaneous (complex) EVAR: 98 had prior open surgical femoral access and 534 patients underwent de novo femoral percutaneous access. A total of 1099 femoral artery punctures were performed: 149 in re-do and 950 in intact groins. The extent of endovascular repair included 159 infrarenal, 82 thoracic, 368 fenestrated/branched, and 23 iliac branch devices. No significant differences were seen in technical success (re-do 93.3% vs intact 95.3%, p=0.311), access-related surgical revision (0.7% vs 0.6%, p=0.950), and access complications (2.7% vs 4.0%, p=0.443). For the whole group, significant predictors for access complications in multivariate analyses were main access site (odds ratio [OR] 2.39; 95% confidence interval [CI] 1.07%-5.35%; p=0.033) and increase of the procedure time per hour (OR 1.65; 95% CI 1.34%-2.04%; p<0.001), while increase in sheath-vessel ratio had a protective effect (OR 0.33; 95% CI 0.127%-0.85%; p=0.021). Surgical conversion was predicted by main access site (OR 2.32; 95% CI 1.28%-4.19%; p=0.007) and calcification of 50% to 75% of the circumference of the access vessel (OR 3.29; 95% CI 1.38%-7.86%; p=0.005). CONCLUSION: Within our population prior open surgical femoral artery exposure or repair had no negative impact on the technical success and clinical outcomes of percutaneous (complex) endovascular aortic aneurysm repair.

Comparing Mobile C-Arm with a Hybrid Operating Room for Imaging in Fenestrated Stent-Graft Endovascular Abdominal Aortic Aneurysm Repair.

BACKGROUND: To evaluate the advantages of a hybrid operating room (OR) (group 2) compared with a fluoroscopic mobile C-arm (group 1) during fenestrated stent-graft endovascular aneurysm repair (f-EVAR). METHODS: This single-center study retrospectively analyzed prospectively collected data of consecutive patients treated with f-EVAR for short-necked, juxtarenal, and suprarenal aortic aneurysms between January 2006 and July 2016. Primary end points were technical success and perioperative complications. Secondary end points included 30-day and 1-year mortality as well as target vessel patency. RESULTS: About 96 patients were treated (85 men; 74.1 ± 6.3 years); 46 patients (48%) belonging to group 1 and 50 (52%) patients belonging to group 2. Technical success was achieved in 92.7% of the procedures (group 1 91.3% vs. group 2 94%, P = 0.72). Significantly more complex interventions were performed in group 2 (n = 38 of 50) compared with group 1 (n = 14 of 46; P < 0.001), in which primarily renal f-EVAR interventions were performed. In group 2, significantly less contrast was used (median 150 mL vs. 100 mL; P < 0.001). The 30-day mortality in group 1 was 9% and 2% in group 2 (P = 0.14), and 1-year survival was also not significantly different between both groups. Target visceral vessel primary patency was significantly higher in group 1 (87.6% vs. 85.5% [P = 0.006] and 83.8% vs. 78.3% [P = 0.03]) at 6 and 12 months, respectively). There was no significant difference in renal artery primary patency at 6 and 12 months. CONCLUSIONS: Immediate and 1-year outcomes after f-EVAR for abdominal aortic aneurysm were comparable using a hybrid OR compared with a mobile C-arm, despite the use of significantly more complex stent grafts in the patients treated in the hybrid OR. The use of a hybrid OR may assist in achieving satisfying results in complex f-EVAR.

Can Electric Nose Breath Analysis Identify Abdominal Wall Hernia Recurrence and Aortic Aneurysms? A Proof-of-Concept Study.

Introduction. This pilot study evaluates if an electronic nose (eNose) can distinguish patients at risk for recurrent hernia formation and aortic aneurysm patients from healthy controls based on volatile organic compound analysis in exhaled air. Both hernia recurrence and aortic aneurysm are linked to impaired collagen metabolism. If patients at risk for hernia recurrence and aortic aneurysms can be identified in a reliable, low-cost, noninvasive manner, it would greatly enhance preventive options such as prophylactic mesh placement after abdominal surgery. Methods. From February to July 2017, a 3-armed proof-of-concept study was conducted at 3 hospitals including 3 groups of patients (recurrent ventral hernia, aortic aneurysm, and healthy controls). Patients were measured once at the outpatient clinic using an eNose with 3 metal-oxide sensors. A total of 64 patients (hernia, n = 29; aneurysm, n = 35) and 37 controls were included. Data were analyzed by an automated neural network, a type of self-learning software to distinguish patients from controls. Results. Receiver operating curves showed that the automated neural network was able to differentiate between recurrent hernia patients and controls (area under the curve 0.74, sensitivity 0.79, and specificity 0.65) as well as between aortic aneurysm patients and healthy controls (area under the curve 0.84, sensitivity 0.83, and specificity of 0.81). Conclusion. This pilot study shows that the eNose can distinguish patients at risk for recurrent hernia and aortic aneurysm formation from healthy controls.

Duplex-guided versus Conventional Percutaneous Transluminal Angioplasty of Iliac TASC II A and B Lesion: A Randomized Controlled Trial.

BACKGROUND: Percutaneous transluminal angioplasty (PTA) requires the use of nephrotoxic contrast. Patients with chronic kidney disease are more prone to develop contrast-induced nephropathy after utilization of contrast. Doppler ultrasound (duplex)-guided PTA (DuPTA) is a novel technique and has recently proven to be a successful alternative to conventional PTA in the treatment of iliac stenotic disease, without the use of contrast. In this randomized controlled trial, we evaluated whether DuPTA is as effective as conventional PTA in the treatment of iliac arterial stenotic disease. METHODS: From June 2013 till January 2017, 142 patients with symptomatic peripheral arterial disease (PAD), with significant (>70%) iliac stenotic lesions (both isolated and patients with multilevel disease without treatment of other lesions), were randomized to receive either conventional PTA or DuPTA of the iliac lesion, regardless of renal function. All patients received an ankle-brachial index, arterial mapping with duplex, and magnetic resonance angiography in the pre-operative work-up. Primary end point was procedural success, defined as passing the guidewire through the stenotic lesion and performing a PTA, with or without stenting. Reduction in peak systolic velocity (PSV) of ≥50% after successful PTA was required in the DuPTA group. Angiographic reduction of more than 50% was required in the interventional group. Decrease in PSV was evaluated in both groups 4 weeks post-procedure. RESULTS: Passing of the guidewire through the stenotic lesion was achieved in 96.5% of the DuPTA group and 98.8% of the PTA group (P = 0.34). Although PSV decreased significantly in both groups 4 weeks post-operative, PSV reduction ≥50% was significantly higher in the DuPTA group, respectively 78% vs. 58% in the PTA group (P < 0.01). The utilization of stents was significantly greater in the DuPTA group (52% vs. 18%, P < 0.01). After correction of potential confounders, significant difference in ≥50% PSV reduction remained; technical success did not differ significantly. CONCLUSIONS: DuPTA is a feasible alternative to conventional PTA in the treatment of PAD on the iliac anatomic level. Duplex examination before removal of the guidewire is recommended to evaluate adequate decrease in PSV and identify potential recoil.

Editor's Choice - Open Thoracic and Thoraco-abdominal Aortic Repair After Prior Endovascular Therapy.

OBJECTIVE: The aim was to present current results of open thoracic and thoraco-abdominal aortic repair as secondary procedure after prior endovascular therapy. METHODS: This was a retrospective cross border single centre study. From 2006 to July 2017 45 open thoracic aortic (TAA) or thoraco-abdominal aortic aneurysm (TAAA) operations were performed on 44 patients (median age 58 [15-80] years) as secondary surgery after previous endovascular therapy comprising TEVAR (n = 38; 86%), EVAR (n = 3; 7%), fenestrated EVAR (n = 1; 2%) and TEVAR plus EVAR (n = 1; 2%). Eleven patients (25%) had had previous open aortic surgery at the secondary surgery site. Indications for TAA(A) repair were Type I endoleak (n = 10; 23%), post-dissection aneurysm progression due to persisting false lumen perfusion (n = 8; 18%), proximal/distal disease progression (n = 16; 36%), device fracture/dislocation (n = 4; 9%), infection (n = 5; 11%), and initial endograft misplacement (n = 1; 2%). The operations included descending thoracic aortic repair (n = 13, 29%), TAAA Type I (n = 4; 9%), Type II (n = 5; 11%), Type III (n = 13; 29%), Type IV (n = 7; 16%), and Type V repair (n = 3; 7%) with simultaneous arch repair in 18% (n = 8). The median time to secondary surgery was 36 (2-168) months. The median follow up was 39 (3-118) months. RESULTS: In hospital mortality was 20% (n = 9) due to intra-operative aneurysm rupture, pneumonia induced sepsis, hemorrhagic cerebellar infarction, mesenteric ischaemia, broncho-esophageal fistula, and multiorgan failure (1/9) as well as haemorrhage (3/9). Estimated survival was 73% at 1 year and 71% overall. The most frequent complications were pneumonia (n = 19; 43%), bleeding requiring revision (n = 11; 25%) and sepsis (n = 14; 32%). Transient dialysis was required in 32% (n = 14), permanent dialysis in 6% (n = 2). Permanent spinal cord deficit (paraparesis) occurred in 6% (n = 2). Estimated freedom from aortic re-intervention was 86%. CONCLUSION: Open TAA(A) repair as a secondary procedure after previous endovascular aortic therapy is an important treatment option even in the endovascular era. It represents a durable treatment that can produce respectable outcomes. Yet the peri-operative morbidity and mortality are relevant and a specialised team and infrastructure are mandatory for these complex procedures. Therefore, centralisation is required.

Editor's Choice - Open Thoracic and Thoraco-abdominal Aortic Repair in Patients with Connective Tissue Disease.

OBJECTIVE/BACKGROUND: The aim is to present current results of open complex aortic repair in patients with connective tissue disease (CTD). METHODS: This was a retrospective cross-border, single centre study. From February 2000 to April 2016 72 aortic operations were performed on 65 patients with CTD (41 male, median age 41 years [range 19-70 years]). Fifty-six patients (86%) underwent at least one previous aortic repair (71 open, four endovascular), including 33 patients (51%) operated before at the site of the procedure reported here. The open procedures, counting eight emergency operations (11%), included aortic arch revision (n = 1; 1%), descending thoracic aortic repair (n = 11; 15%), TAAA type I repair (n = 12; 17%), type II repair (n = 29; 40%), type III repair (n = 12; 17%), and type IV repair (n = 5; 7%). Simultaneous repair of the ascending aorta and/or the aortic arch was performed in two (3%) and eight cases (11%), respectively. Seven patients (10%) underwent staged procedures. Median follow-up was 42 months (0.5-180 months). RESULTS: The in hospital mortality was 14% (n = 9) as a result of haemorrhage (n = 3/9), neurological (n = 3/9), cardiac (n = 2/9), and pulmonary (n = 1/9) complications. Paraplegia and paraparesis occurred in one (2%) and three patients (5%), respectively. Seven patients (11%) required temporary dialysis; none needed permanent dialysis. Major complications were revision surgery for bleeding or haematoma (n = 20/65), sepsis (n = 10/65), myocardial infarction/severe cardiac arrhythmia (n = 2/65), stroke (n = 2/65), as well as multiorgan failure, abdominal compartment syndrome, mesenteric and peripheral ischaemia (all n = 1/65). Multivariate analysis identified an operating time > 7 hours (p = .006) as an independent predictor of increased mortality. Freedom from re-intervention was 85%, 1 year survival was 80%, and overall survival was 75%. CONCLUSION: Open TAA(A) repair is a durable therapy for patients with CTD. Often being performed as revision surgery, it can be associated with relevant risks and should therefore be reserved for specialised centres. Staged procedures and thus reducing operating time, if applicable, should be preferred.

Loss of Kidney Function after Endovascular Treatment of Peripheral Arterial Disease.

BACKGROUND: Administration of radiocontrast during endovascular procedures for peripheral arterial disease (PAD) may cause acute kidney injury, which generally recovers with supportive treatment. Long-term effects of endovascular procedures on renal function remain to be investigated. METHOD: This retrospective observational cohort study includes all patients who newly presented to the vascular surgery outpatient clinic with Rutherford class II or III PAD and who were treated with either supervised exercise therapy or endovascular interventions. Changes in estimated glomerular filtration rates (eGFR) after 1 year were compared between the 2 treatment groups. Multivariate regression analysis and propensity score-matched paired analysis were done to correct for potential confounders. RESULTS: One year after treatment, eGFR was reduced by 8.6 mL/min (95% confidence interval [CI], 7.3-9.9, P < 0.001) after endovascular intervention (n = 284) and by 1.7 mL/min (95% CI, 0.9-25, P < 0.001) after supervised exercise therapy (n = 299). After correction for potential confounders, endovascular interventions were associated with 9.2 mL/min (95% CI, 5.9-12.4, P < 0.001) more renal decline compared to exercise therapy. Similar results were found in the propensity score-matched paired analysis. CONCLUSIONS: Endovascular procedures for PAD are associated with clinically relevant and long-term loss of kidney function.

Loss of kidney function in patients with critical limb ischemia treated endovascularly or surgically.

BACKGROUND: Acute kidney injury after the administration of contrast material during endovascular procedures for peripheral arterial disease generally recovers with supportive treatment. However, long-term effects of endovascular procedures for critical limb ischemia on renal function remain to be investigated. METHODS: This retrospective observational cohort study included all patients who newly presented to the vascular surgery outpatient clinic with Rutherford class 4 to class 6 peripheral arterial disease and who were treated with either endovascular or surgical interventions. Changes in estimated glomerular filtration rate (eGFR) after 1 year were compared between the two types of intervention. Multivariate linear regression analysis was done to correct for potential confounders. RESULTS: One year after treatment, eGFR was reduced by 15.0 mL/min (95% confidence interval [CI], 13.1-17.0; P < .001) after endovascular interventions (n = 209) and by 7.6 mL/min (95% CI, 5.1-10.0; P < .001) after surgical therapy (n = 81). Although eGFR rates decreased in both groups, loss of renal function was significantly greater in patients after endovascular interventions (P < .001). Furthermore, 77% of patients receiving endovascular interventions experienced fast renal decline (defined as >4 mL/min loss of eGFR within 1 year) compared with 54% of patients treated surgically (P < .001). After correction for potential confounders, endovascular intervention was associated with 7.4 mL/min (95% CI, 5.4-9.3; P < .001) greater loss of renal function compared with patients treated surgically. CONCLUSIONS: Endovascular procedures for critical limb ischemia are associated with clinically relevant permanent long-term loss of kidney function. This loss of renal function is greater than in comparable patients who were treated with open surgery.

Endovascular treatment of complex aortic aneurysms: prevalence of acute kidney injury and effect on long-term renal function.

OBJECTIVES: To analyse predictors for short- and long-term renal function changes after fenestrated and branched endovascular aortic repair (EVAR). METHODS: A total of 157 patients underwent fenestrated and branched EVAR. Procedural intra-arterial iodinated contrast volume was documented. Serum creatinine and estimated glomerular filtration rate (eGFR) at baseline, during 48 h following EVAR, at discharge and latest moment of follow-up were recorded. Development of post-EVAR acute kidney injury (AKI; according to AKIN criteria), and potential risk factors for renal failure were recorded. Multivariate regression analyses were used to identify independent risk factors for AKI and eGFR decrease during follow-up. RESULTS: Forty-three patients (28 %) developed post-EVAR AKI. Long procedure time and occlusion of accessory renal arteries were independent risk factors for development of AKI. (odds ratio (OR) 1.005 per minute, 95 % CI 1.001-1.01; p = 0.025 and OR 3.02, 95 % CI 1.19-8.16; p = 0.029). Post-EVAR AKI was associated with a significantly increased risk for eGFR decrease at discharge and latest follow-up (hazard ratio (HR) 3.47, 95 % CI 1.63-7.36, p = 0.001 and HR 3.01, 95 % CI 1.56-5.80; p = 0.001). Iodinated contrast volume was not an independent risk factor for AKI or eGFR decrease during follow-up. CONCLUSION: Development of post-EVAR AKI is an independent risk factor for long-term renal function decrease. KEY POINTS: • Longer procedure time is associated with an increased risk for AKI. • Renal perfusion defects on angiography are associated with increased risk for AKI. • Post-EVAR AKI is associated with higher probability for long-term eGFR decrease. • Iodinated contrast volume is not an independent risk factor for AKI. • Iodinated contrast volume is not an independent risk factor for long-term eGFR decrease.

Individualized CT Angiography Protocols for the Evaluation of the Aorta: A Feasibility Study.

PURPOSE: Ionizing radiation and iodinated contrast media are potential drawbacks to repetitive follow-up CT angiography in current practice. The aim of the present study was to optimize radiation dose and contrast agent volume by using individualized CT angiography protocols. MATERIALS AND METHODS: Eighty consecutive patients referred for CT angiography of the whole aorta were prospectively evaluated. Patients were divided into groups of patients with a body mass index (BMI) < 28 kg/m(2) (group 1; n = 50) and those with a BMI ≥ 28 kg/m(2) (group 2; n = 30). A control group consisted of 50 consecutive patients who were retrospectively evaluated. CT angiography parameters on a second-generation dual-source scanner were 128 × 0.6-mm collimation, pitch of 0.9, rotation time of 0.33 seconds, tube voltages of 80/100/120 kVp (group 1/group 2/control), reference tube current of 400 mA, and image reconstruction at 1-mm/0.8-mm slice thickness (kernels, B30f [control] and I30f/strength 3 [groups 1/2]). The control group received 120 mL of contrast agent (300 mgI/mL) at 4.8 mL/s; groups 1 and 2 received 44 mL and 53 mL at 3.3 mL/s and 4 mL/s, respectively. Effective dose was evaluated for each patient. Image quality was determined by qualitative image analysis at the levels of the thoracic, abdominal, and pelvic aorta as nondiagnostic, diagnostic, good, or excellent, and quantitative image analysis was performed, including attenuation values and contrast-to-noise ratio (CNR). RESULTS: Mean effective radiation dose values for CT angiography of the aorta were 3.7 mSv ± 0.7 in group 1, 6.7 mSv ± 1.4 in group 2, and 8.7 mSv ± 1.9 in the control group (P < .001). Mean attenuation values and CNR levels were 334 HU ± 66 and 16 ± 8, respectively, in group 1, 277 HU ± 56 and 14 ± 5 in group 2, and 305 HU ± 77 and 11 ± 4 in the control group. CONCLUSIONS: Iterative reconstruction algorithms resulted in 23%-57% less radiation in combination with 55%-63% less contrast agent volume compared with standard CT protocols.

Radiation Exposure during Percutaneous Transluminal Angioplasty for Symptomatic Peripheral Arterial Disease.

BACKGROUND: Endovascular interventions often are the preferred treatment in peripheral arterial disease for both intermittent claudication and chronic critical limb ischemia. Ever more advanced and anatomically complex procedures are being performed, which may increase the radiation exposure of patients and medical staff. We sought to determine the radiation exposure sustained in contemporary interventional radiology practice. METHODS: A single-center observational cohort study of patients undergoing endovascular interventions for symptomatic peripheral arterial disease between January 1st, 2011 and July 31st, 2013 was performed. Radiation dose area product (DAP), peak skin dose (PSD), fluoroscopy time, and volume of contrast media were either measured or calculated and stratified according to patient demographics and anatomic location. RESULTS: In 951 patients, who were treated with endovascular interventions, mean DAP was 108 ± 88 Gy × cm(2) and mean fluoroscopy time was 13 ± 12 min. DAP was significantly higher for aortoiliac procedures (142 ± 103 Gy × cm(2)) compared with femoral (58 ± 73 Gy × cm(2)), below-knee (45 ± 51 Gy × cm(2)) and multilevel (83 ± 90 Gy × cm(2)) procedures (P < 0.001 for all comparisons). PSD was significantly higher for aortoiliac procedures (0.99 ± 0.54 Gy) compared with femoral (0.55 ± 0.55 Gy), below-knee (0.48 ± 0.27 Gy), and multilevel (0.68 ± 0.47 Gy) procedures (P < 0.001 for all comparisons). In contrast, mean fluoroscopy time in aortoiliac interventions was significantly shorter (10 ± 15 min) compared with femoral (15 ± 12 min), below-knee (19 ± 10 min), and multilevel (23 ± 14 min) procedures (P < 0.001 for all comparisons). CONCLUSIONS: Endovascular interventions in patients with symptomatic peripheral arterial disease involve a substantial radiation dose. Although fluoroscopy time is shorter, aortoiliac interventions result in greater radiation exposure than femoropopliteal or infrapopliteal interventions.

Feasibility of wall stress analysis of abdominal aortic aneurysms using three-dimensional ultrasound.

OBJECTIVE: Abdominal aortic aneurysms (AAAs) are local dilations that can lead to a fatal hemorrhage when ruptured. Wall stress analysis of AAAs is a novel tool that has proven high potential to improve risk stratification. Currently, wall stress analysis of AAAs is based on computed tomography (CT) and magnetic resonance imaging; however, three-dimensional (3D) ultrasound (US) has great advantages over CT and magnetic resonance imaging in terms of costs, speed, and lack of radiation. In this study, the feasibility of 3D US as input for wall stress analysis is investigated. Second, 3D US-based wall stress analysis was compared with CT-based results. METHODS: The 3D US and CT data were acquired in 12 patients (diameter, 35-90 mm). US data were segmented manually and compared with automatically acquired CT geometries by calculating the similarity index and Hausdorff distance. Wall stresses were simulated at P = 140 mm Hg and compared between both modalities. RESULTS: The similarity index of US vs CT was 0.75 to 0.91 (n = 12), with a median Hausdorff distance ranging from 4.8 to 13.9 mm, with the higher values found at the proximal and distal sides of the AAA. Wall stresses were in accordance with literature, and a good agreement was found between US- and CT-based median stresses and interquartile stresses, which was confirmed by Bland-Altman and regression analysis (n = 8). Wall stresses based on US were typically higher (+23%), caused by geometric irregularities due to the registration of several 3D volumes and manual segmentation. In future work, an automated US registration and segmentation approach is the essential point of improvement before pursuing large-scale patient studies. CONCLUSIONS: This study is a first step toward US-based wall stress analysis, which would be the modality of choice to monitor wall stress development over time because no ionizing radiation and contrast material are involved.

Quantification of Respiratory Movement of the Aorta and Side Branches.

PURPOSE: To assess and quantify the magnitude and direction of respiratory movement of the aorta and origins of its side branches. METHODS: A quantitative 3-dimensional (3D) subtraction analysis of computed tomography (CT) scans during inspiration and expiration was performed to determine the respiratory geometric movements of the aorta and side branches in 60 patients. During breath-hold expiration and inspiration, 1-mm-thick CT slices of the aorta were acquired in unenhanced and contrast-enhanced scans. The datasets were compared using dedicated multiplanar reformation image subtraction software to determine the change in position of relevant anatomic sections, including the ascending thoracic aorta (AA), the origins of the brachiocephalic artery (BA) and left subclavian artery (LSA), the descending thoracic aorta (DTA) at the level of the tenth thoracic vertebra, as well as the origins of the celiac trunk, superior mesenteric artery, and the renal arteries. RESULTS: Complex movement was visible during inspiration; the regions of interest in the thoracic aorta and side branches moved in the anterior, medial, and caudal directions compared with the expiration state. Mean 3D movement vectors (± standard deviation) were 8.9±3.6 mm (AA), 12.0±4.1 mm (BA), 11.1±3.9 mm (LSA), and 4.9±2.5 mm (DTA). Abdominal side branches moved in the caudal direction 1.3±1.1 mm. There was significantly less movement in the DTA compared to AA (p<0.001). The correlation coefficient between the extent of LSA movement and thoracic excursion was 0.78. CONCLUSION: The aorta and side branches undergo considerable respiratory movement. The results from this study provide an important contribution to understanding aortic dynamics.

Dutch experience with the fenestrated Anaconda endograft for short-neck infrarenal and juxtarenal abdominal aortic aneurysm repair.

OBJECTIVE: In the past decennium, the management of short-neck infrarenal and juxtarenal aortic aneurysms with fenestrated endovascular aneurysm repair (FEVAR) has been shown to be successful, with good early and midterm results. Recently, a new fenestrated device, the fenestrated Anaconda (Vascutek, Renfrewshire, Scotland), was introduced. The aim of this study was to present the current Dutch experience with this device. METHODS: A prospectively held database of patients treated with the fenestrated Anaconda endograft was analyzed. Decision to treat was based on current international guidelines. Indications for FEVAR included an abdominal aortic aneurysm (AAA) with unsuitable neck anatomy for EVAR. Planning was performed on computed tomography angiography images using a three-dimensional workstation. RESULTS: Between May 2011 and September 2013, 25 patients were treated in eight institutions for juxtarenal (n = 23) and short-neck AAA (n = 2). Median AAA size was 61 mm (59-68.5 mm). All procedures except one were performed with bifurcated devices. A total of 56 fenestrations were incorporated, and 53 (94.6%) were successfully cannulated and stented. One patient died of bowel ischemia caused by occlusion of the superior mesenteric artery. On completion angiography, three type I endoleaks and seven type II endoleaks were observed. At 1 month of follow-up, all endoleaks had spontaneously resolved. Median follow-up was 11 months (range, 1-29 months). There were no aneurysm ruptures or aneurysm-related deaths and no reinterventions to date. Primary patency at 1 month of cannulated and stented target vessels was 96%. CONCLUSIONS: Initial and short-term results of FEVAR using the fenestrated Anaconda endograft are promising, with acceptable technical success and short-term complication rates. Growing experience and long-term results are needed to support these findings.

Quantification of abdominal aortic aneurysm wall enhancement with dynamic contrast-enhanced MRI: feasibility, reproducibility, and initial experience.

PURPOSE: To investigate the feasibility and reproducibility of dynamic contrast-enhanced MRI (DCE-MRI) to quantify abdominal aortic aneurysm (AAA) vessel wall enhancement dynamics which may reflect the amount of wall microvasculature. AAA vessel wall microvasculature has been linked with aneurysm progression and rupture. MATERIALS AND METHODS: Thirty patients with AAA underwent DCE-MRI at 1.5 Tesla. Enhancement dynamics of the aneurysm wall were quantified in regions-of-interest (ROIs) in the vessel wall by calculating the transfer constant (K(trans) ) using pharmacokinetic modeling and the area-under-gadolinium-curve (AUC). To assess reproducibility, 10 patients were imaged twice on different occasions. ROIs were drawn by two independent observers. The intraclass correlation coefficients (ICC) and coefficients of variation (CV) were determined to investigate intra-, interobserver, and interscan variability. RESULTS: Twenty-eight analyzable MR examinations were included for pharmacokinetic analysis after excluding two examinations due to severe motion artifacts. Intra-, interobserver, and interscan variability for K(trans) were small (all ICC > 0.90, CV < 14%) as well as for AUC measurements (all ICC > 0.88, CV < 23%). CONCLUSION: Quantitative analysis of AAA vessel wall enhancement dynamics with DCE-MRI is feasible and reproducible.

Circulating intestinal fatty acid-binding protein as an early marker of intestinal necrosis after aortic surgery: a prospective observational cohort study.

OBJECTIVE: This study evaluated the usefulness of plasma intestinal fatty-acid binding protein (IFABP) levels in the early identification of intestinal necrosis (IN) in patients undergoing different types of aortic surgery. BACKGROUND: Intestinal compromise greatly contributes to postoperative adverse outcome. IN is the most detrimental form of intestinal compromise and is notoriously difficult to diagnose. IFABP is a small protein exclusively expressed by mature enterocytes and a promising marker of intestinal damage. METHODS: Plasma IFABP concentrations were measured in blood samples taken perioperatively from 55 patients undergoing open thoracic or thoracoabdominal aneurysm repair [OR-TAA(A)], 25 patients undergoing conventional open abdominal aneurysm repair (OR-abdominal aortic aneurysm [AAA]), and 16 patients undergoing endovascular aneurysm repair (EVAR). Data were compared with perioperative changes in arterial pH and serum lactate levels. RESULTS: IFABP levels increased in all patients undergoing OR-TAA(A) and OR-AAA reaching peak levels shortly after surgery; 281 ± 33 to 2,298 ± 490 pg/mL (P < 0.001) and 187 ± 31 to 641 ± 176 pg/mL (P < 0.05) respectively. IFABP levels were significantly higher in patients undergoing OR-TAA(A) (P < 0.001). IFABP levels in EVAR patients remained at baseline concentrations throughout the study. Four patients [2 OR-AAA, 2 OR-TAA(A)] developed fatal postoperative intestinal ischemia on day 2 or 3. High levels of plasma IFABP at the end of surgery had 100% sensitivity and 98.1% specificity for the identification of patients developing IN. In OR-AAA patients, arterial pH and lactate levels were of additional discriminating value. Complete discrimination between patients with and without IN using plasma IFABP could be made on the first postoperative day. CONCLUSIONS: Analysis of plasma IFABP levels is of additional value to other current plasma markers in the diagnosis of IN, and it enables early identification of patients with IN after aortic surgery days before clinical diagnosis.

Circulating biomarkers and abdominal aortic aneurysm size.

BACKGROUND: Abdominal aortic aneurysm (AAA) is a degenerative disease of the abdominal aorta leading to progressive dilatation, intra-luminal thrombus (ILT) formation, and rupture. Understanding the natural history of AAA is essential, because different processes and, therefore, different biomarkers, could be involved at each stage of disease progression. The purpose of the present study was to investigate the relationship between systemic expression of biomarkers of inflammation and extracellular matrix remodeling and aneurysm size in AAA patients. METHODS AND RESULTS: All consecutive patients admitted to the (out-) patient clinic of the surgical department of two large community centers were prospectively included. Patients were divided into three groups based on their aneurysm diameter: small (30-44 mm; n = 59), medium-sized (45-54 mm; n = 64) or large (≥ 55 mm; n = 95) AAA. Linear regression modeling showed that age and serum hsCRP concentration were positively associated, whereas serum HDL and IgG concentrations were negatively associated with aneurysm size. This regression model was corrected for possible bias due to statin use and center of inclusion; and also indicated that in general men have larger aneurysms compared with women. CONCLUSIONS: Different aneurysm sizes showed different expression pattern of HDL, IgG, and hsCRP. These biomarkers may be useful in predicting AAA progression.