Identifying Patients at High Risk for Post-EVAR Aneurysm Sac Growth.

PURPOSE: Post-EVAR (endovascular aneurysm repair) aneurysm sac growth can be seen as therapy failure as it is a risk factor for post-EVAR aneurysm rupture. This study sought to identify preoperative patient predictors for developing post-EVAR aneurysm sac growth. MATERIAL AND METHODS: A systematic review was conducted to select potential predictive preoperative factors for post-EVAR sac growth (including a total of 34.886 patients), which were evaluated by a retrospective single-center analysis of patients undergoing EVAR between 2009 and 2019 (N=247) with pre-EVAR computed tomography scans and at least 1 year follow-up. The primary study outcome was post-EVAR abdominal aortic aneurysm (AAA) sac enlargement (≥5 mm diameter increase). Multivariate Cox regression and Kaplan-Meier survival curves were constructed. RESULTS: Potential correlative factors for post-EVAR sac growth included in the cohort analysis were age, sex, anticoagulants, antiplatelets, renal insufficiency, anemia, low thrombocyte count, pulmonary comorbidities, aneurysm diameter, neck diameter, neck angle, neck length, configuration of intraluminal thrombus, common iliac artery diameter, the number of patent lumbar arteries, and a patent inferior mesenteric artery. Multivariate analysis showed that infrarenal neck angulation (hazard ratio, 1.014; confidence interval (CI), 1.001-1.026; p=0.034) and the number of patent lumbar arteries (hazard ratio, 1.340; CI, 1.131-1.588; p<0.001) were associated with post-EVAR growth. Difference in estimated freedom from post-EVAR sac growth for patients with ≥4 patent lumbar arteries versus <4 patent lumbar arteries became clear after 2 years: 88.5% versus 100%, respectively (p<0.001). Of note, 31% of the patients (n=51) with ≥4 patent lumbar arteries (n=167) developed post-EVAR sac growth. In our cohort, the median maximum AAA diameter was 57 mm (interquartile range [IQR] = 54-62) and the median postoperative follow-up time was 54 months (IQR = 34-79). In all, 23% (n=57) of the patients suffered from post-EVAR growth. The median time for post-EVAR growth was 37 months (IQR = 24-63). In 46 of the 57 post-EVAR growth cases (81%), an endoleak was observed; 2.4% (n=6) of the patients suffered from post-EVAR rupture. The total mortality in the cohort was 24% (n=60); 4% (n=10) was AAA related. CONCLUSIONS: This study showed that having 4 or more patent lumbar arteries is an important predictive factor for postoperative sac growth in patients undergoing EVAR. CLINICAL IMPACT: This study strongly suggests that having 4 or more patent lumbar arteries should be included in preoperative counseling for EVAR, in conjunction to the instructions for use (IFU).

Stent Graft Sizing for Endovascular Abdominal Aneurysm Repair Using Open Source Image Processing Software.

INTRODUCTION: An important step to reach a favorable outcome of abdominal endovascular aneurysm repair (EVAR) is preoperative sizing of the stent graft using computed tomography angiography (CTA) images of the abdominal aorta. A variety of costly image processing software options is available to obtain the necessary aortic measurements. A package that can be used for EVAR sizing is OsiriX Lite®-an open source, freely downloadable image processing option. This study assesses the concurrent validity of OsiriX Lite® when compared with commercially available 3Mensio Vascular® and Siemens Syngo.via®. METHODS: CTA scans of 20 patients that underwent EVAR for abdominal aneurysm were selected, 10 elective and 10 ruptured. For each scan, 6 observers determined 20 parameters needed for proper stent graft sizing, 2 using Osirix Lite®, 3 using 3Mensio Vascular®, and 1 using Siemens Syngo.via®. For each parameter, an intraclass correlation coefficient (ICC) and a P-value were calculated. Interrater agreement was interpreted using the Koo and Li Guidelines. Time needed to perform EVAR planning was compared. RESULTS: Overall interrater agreement between the 3 sizing options was found to be either "good" or "moderate" for 16 out of 20 parameters (80%). Time needed to perform EVAR planning was not significantly different for Osirix Lite® (568 sec) when compared with 3Mensio Vascular® (603 sec) or Siemens Syngo.via® (659 sec) with a P-value of 0.88. CONCLUSIONS: The authors conclude that Osirix Lite® is an accurate and time-effective image processing option for preoperative sizing of an EVAR stent graft when matched to 3Mensio Vascular® and Siemens Syngo.via®.

Nationwide study of the treatment of mycotic abdominal aortic aneurysms comparing open and endovascular repair in The Netherlands.

OBJECTIVE: Mycotic aneurysms of the abdominal aorta (MAAA) can be treated by open repair (OR) or endovascular aneurysm repair (EVAR). This nationwide study provides an overview of the situation of MAAA treatment in The Netherlands in 2016. METHODS: A retrospective cohort study was conducted with all centers that registered aortic abdominal aneurysms in the Dutch Surgical Aneurysm Audit in 2016. Questionnaires on 1-year outcomes were sent to all centers that treated patients with MAAA. The primary aim was to determine 30-day and 1-year mortality and morbidity of OR- and EVAR-treated patients. Morbidity was determined by the need for reoperations and the number of readmissions to the hospital. RESULTS: Twenty-six MAAA were detected in the Dutch Surgical Aneurysm Audit database of 2016, resulting in an incidence of 0.7% of all registered abdominal aortic aneurysms. The 30-day mortality for OR and EVAR treated patients was 1 in 13 and 0 in 13, respectively. Major and minor reinterventions within 30 days were needed for two (one OR and one EVAR) and two (one OR and one EVAR) patients, respectively. Two patients (15.4%) in the OR group and one patient (7.7%) in the EVAR group were readmitted to hospital within 30 days. In total, 1-year outcomes of 23 patients were available. In the OR group, one patient (9.1%) died in the first postoperative year. There was one major reintervention (removal of endoprosthesis and spiralvein reconstruction) in the EVAR group. Two patients (18.2%) treated with OR and two (16.7%) treated with EVAR required a minor reintervention. In both groups, four patients (OR, 36.4%; EVAR, 33.3%) were readmitted to hospital within 1 year postoperatively. CONCLUSIONS: Both OR- and EVAR-treated patients show acceptable clinical outcomes after 30 days and at the 1-year follow-up. Depending on the clinical course of the patient, EVAR may be considered in the management of this disease.

Clinical outcomes of postcarotid endarterectomy hypertension.

OBJECTIVE: The objective of this study was to determine the clinical relevance of postcarotid endarterectomy hypertension (PEH) by investigating the effect of PEH on hospital length of stay (LOS) and by investigating short-term and long-term complications of PEH. In addition, risk factors for PEH were determined. METHODS: A single-center retrospective cohort study was performed. Demographic, preoperative, intraoperative, and postoperative outcomes of 192 patients undergoing carotid endarterectomy were evaluated. Outcomes were compared between patients with PEH and patients without PEH. PEH was defined as an acute systolic blood pressure (SBP) rise >170 mm Hg or persistent SBP >150 mm Hg on the ward and leading to the consultation of an internist. The overall survival and event-free survival were compared using a Kaplan-Meier analysis and a Cox regression analysis. A multivariate logistic regression analysis was performed to determine risk factors for PEH. RESULTS: PEH developed in 44 of 192 patients (25%). Preoperative hypertension (SBP >150 mm Hg) was determined to be a risk factor for PEH (odds ratio, 3.3; 95% confidence interval [CI], 1.6-6.9). Hospital LOS was prolonged in patients with PEH compared with patients without PEH (median LOS of 5 days vs 3 days, respectively; P < .001). No difference in the occurrence of ischemic neurologic events or rebleeding during hospitalization was observed (P = .58 and P = .72, respectively). Cardiovascular and ischemic neurologic events during follow-up did not occur more often in patients with PEH than in patients without PEH (P = .46). There was no difference in mortality between the PEH and non-PEH groups (hazard ratio, 1.6; 95% CI, 0.6-4.3). The same applies to the event-free survival (hazard ratio, 0.77; 95% CI, 0.4-1.7). Combined event-free survival for stroke and myocardial infarction was 92% (95% CI, 87%-97%) at 2 years for patients without PEH and 86% (95% CI, 74%-98%) at 2 years for patients with PEH (P = .25). Event-free survival for mortality was 90% (95% CI, 85%-96%) at 2 years for patients without PEH and 94% (95% CI, 86%-100%) at 2 years for patients with PEH (P = .36). CONCLUSIONS: Patients with PEH had a significant increase in hospital LOS. However, adverse short-term and long-term events did not occur more often in patients with PEH. High preoperative SBP was identified as a risk factor for PEH; no other demographic and clinical variables were associated with PEH.

Chimney Technique to Preserve Visceral Flow in a Coral Reef Aorta.

The coral reef aorta (CRA) is a rare phenomenon of extreme calcification in the juxtarenal and suprarenal aorta. Open revascularization has an overall in-hospital mortality rate of 13%. We present a patient with a suprarenal CRA with colon ischemia. She has an extensive past medical history of percutaneous transluminal angioplasty and stenting of the celiac trunk (CT) and superior mesenteric artery (SMA). The computed tomography angiography showed a CRA of the suprarenal aorta with occlusion of the CT stent and near occlusion of the SMA stent. Our case illustrates that the CRA in the suprarenal part of the aorta can be treated well by chimney graft procedure, although owing to lack of long-term follow-up, it might be reserved for high-risk candidates for (thoraco)abdominal aortic surgery.

Endovascular Revascularization of a Chronic Occluded Aortobifemoral Bypass.

Bilateral limb occlusion after aortobifemoral (ABF) prosthesis occurs in 1-3% patients. Multiple remedial choices are known in literature to manage a bilateral occluded ABF such as "redo" ABF bypass, axillobifemoral bypass, endovascular recanalization of the native aortoiliac system, and thrombectomy. We present a patient with an occluded ABF bypass since 2001. A new minimal invasive treatment strategy was performed by traversing the occluded limbs with aortic re-entry using stiff Terumo wires. To make way for safe passing of the stents, kissing balloon angioplasty was performed of the entire ABF bypass. Kissing Viabahn (W. L. Gore & Associates, Flagstaff, AZ) balloon-expandable stents were placed in the proximal part of the ABF bypass and extended with a Viabahn self-expandable stent (standard Viabahn). This option should be added to the known multiple remedial choices in case of bilateral limb occlusion of an ABF.

Determinants of Acute Kidney Injury and Renal Function Decline After Endovascular Abdominal Aortic Aneurysm Repair.

OBJECTIVE/BACKGROUND: Endovascular aneurysm repair (EVAR) may be associated with renal injury and more insight is needed into potential risk factors. The aim was to identify clinical, anatomical, and peri-procedural parameters as potential risk factors for the occurrence of acute kidney injury (AKI) and to evaluate chronic kidney disease (CKD) after EVAR. METHODS: A cohort of 212 consecutive patients who underwent elective EVAR for abdominal aortic aneurysm from January 2009 to October 2016 was included. A subgroup of 149 patients with 2 years follow-up was compared with a set of 135 non-operated aneurysm patients with smaller aneurysms (similar cardiovascular risk profile) to assess CKD. Primary outcomes were AKI (Acute Kidney Injury Network criteria) and CKD measured by estimated glomerular filtration rate (Kidney Disease Improving Global Outcomes guidelines). For AKI, candidate risk factors were identified by univariate and multivariate logistic regression analysis; for chronic renal function decline, risk factors were identified using Cox regression analysis. RESULTS: AKI occurred in 30 patients (15%). On multivariate analysis, the use of angiotensin II blocker (odds ratio [OR] 4.08, 95% confidence interval [CI] 1.38-12.07) and peri-operative complications (OR 3.12, 95% CI 1.20-8.10) were independent risk factors for AKI, whereas statin use was a protective factor (OR 0.19, 95% CI 0.07-0.52). EVAR resulted in a significant increase (23.5%) in the occurrence of CKD compared with the control group (6.7%; p <.001). On univariate and multivariate Cox regression the risk factors: aortic neck diameter (per mm increase) (hazard ratio [HR] 1.13, 95% CI 1.02-1.25), renal artery stenosis >50% (HR 2.24, 95% CI 1.05-4.79), and the occurrence of AKI (HR 2.19, 95% CI 0.99-4.85) were significant predictors of CKD. CONCLUSION: This study identified use of angiotensin II blockers and peri-operative complications as risk factors for AKI. In addition, the problem of renal function decline after EVAR is highlighted, which indicates that prolonged protective measures (e.g., in those patients at high risk) over time are needed to improve patient outcomes.

Focal Aortic Dissection With Significant Stenosis: A Rare Long Term Complication After TEVAR for Blunt Traumatic Aortic Injury in an Adolescent Patient.

Background: Thoracic endovascular aortic repair (TEVAR) in children and adolescents after blunt traumatic aortic injury (BTAI) is being performed increasingly despite no endovascular graft being approved for TEVAR in this population. The smaller diameter of the aorta and access vessels and steeper angle of the aortic arch pose specific challenges for TEVAR in this population. Moreover, data are lacking regarding medium to long term complications. This case presents an adolescent patient who underwent TEVAR for BTAI and suffered a focal aortic dissection several months later. Report: The patient initially presented after a motor vehicle accident and underwent an uncomplicated TEVAR procedure with a 28 mm diameter stent graft (the smallest device available at the time) for Grade III traumatic aortic dissection; the native aortic diameter was 15 mm. The diameter mismatch was accepted due to the lifesaving nature of the procedure. More than 7 months later the patient presented to the emergency department after not being able to urinate for several days and experiencing pain, tingling, and weakness in both legs. Blood samples showed a severe acute kidney injury and computed tomography angiography showed significant aortic stenosis in the distal part of the stent graft, probably caused by a focal dissection. The stenosis and dissection were successfully treated using a Palmaz stent, after which his renal function and extremity complaints recovered. Conclusion: The focal dissection was probably caused by stress on the aortic wall due to the aorta-stent graft diameter mismatch. This case demonstrates that complications after TEVAR in adolescents can arise months after the initial procedure and underscores the need for continued vigilance, especially in cases with an aorta-stent graft mismatch. The threshold for additional imaging and consultation by a vascular surgeon should be low.

Wall Shear Stress Assessment of the False Lumen in Acute Type B Aortic Dissection Visualized by 4-Dimensional Flow Magnetic Resonance Imaging: An Ex-Vivo Study.

BACKGROUND: Four-dimensional flow magnetic resonance imaging (4D flow MRI) can accurately visualize and quantify flow and provide hemodynamic information such as wall shear stress (WSS). This imaging technique can be used to obtain more insight in the hemodynamic changes during cardiac cycle in the true and false lumen of uncomplicated acute Type B Aortic Dissection (TBAD). Gaining more insight of these forces in the false lumen in uncomplicated TBAD during optimal medical treatment, might result in prediction of adverse outcomes. METHODS: A porcine aorta dissection model with an artificial dissection was positioned in a validated ex-vivo circulatory system with physiological pulsatile flow. 4D flow MR images with 3 set heartrates (HR; 60 bpm, 80 bpm and 100 bpm) were acquired. False lumen volume per cycle (FLV), mean and peak systolic WSS were determined from 4D flow MRI data. For validation, the experiment was repeated with a second porcine aorta dissection model. RESULTS: During both experiments an increase in FLV (initial experiment: ΔFLV = 2.05 ml, p < 0.001, repeated experiment: ΔFLV = 1.08 ml, p = 0.005) and peak WSS (initial experiment: ΔWSS = 1.2 Pa, p = 0.004, repeated experiment: ΔWSS = 1.79 Pa, p = 0.016) was observed when HR increased from 60 to 80 bpm. Raising the HR from 80 to 100 bpm, no significant increase in FLV (p = 0.073, p = 0.139) was seen during both experiments. The false lumen mean WSS increased significant during initial (2.71 to 3.85 Pa; p = 0.013) and non-significant during repeated experiment (3.22 to 4.00 Pa; p = 0.320). CONCLUSION: 4D flow MRI provides insight into hemodynamic dimensions including WSS. Our ex-vivo experiments showed that an increase in HR from 60 to 80 bpm resulted in a significant increase of FLV and WSS of the false lumen. We suggest that strict heart rate control is of major importance to reduce the mean and peak WSS in uncomplicated acute TBAD. Because of the limitations of an ex-vivo study, 4D flow MRI will have to be performed in clinical setting to determine whether this imaging model would be of value to predict the course of uncomplicated TBAD.

Different Lower Extremity Arterial Calcification Patterns in Patients with Chronic Limb-Threatening Ischemia Compared with Asymptomatic Controls.

OBJECTIVES: The most severe type of peripheral arterial disease (PAD) is critical limb-threatening ischemia (CLI). In CLI, calcification of the vessel wall plays an important role in symptoms, amputation rate, and mortality. However, calcified arteries are also found in asymptomatic persons (non-PAD patients). We investigated whether the calcification pattern in CLI patients and non- PAD patients are different and could possibly explain the symptoms in CLI patients. MATERIALS AND METHODS: 130 CLI and 204 non-PAD patients underwent a CT of the lower extremities. This resulted in 118 CLI patients (mean age 72 ± 12, 70.3% male) that were age-matched with 118 non-PAD patients (mean age 71 ± 11, 51.7% male). The characteristics severity, annularity, thickness, and continuity were assessed in the femoral and crural arteries and analyzed by binary multiple logistic regression. RESULTS: Nearly all CLI patients have calcifications and these are equally frequent in the femoropopliteal (98.3%) and crural arteries (97.5%), while the non-PAD patients had in just 67% any calcifications with more calcifications in the femoropopliteal (70.3%) than in the crural arteries (55.9%, p < 0.005). The crural arteries of CLI patients had significantly more complete annular calcifications (OR 2.92, p = 0.001), while in non-PAD patients dot-like calcifications dominated. In CLI patients, the femoropopliteal arteries had more severe, irregular/patchy, and thick calcifications (OR 2.40, 3.27, 1.81, p ≤ 0.05, respectively) while in non-PAD patients, thin continuous calcifications prevailed. CONCLUSIONS: Compared with non-PAD patients, arteries of the lower extremities of CLI patients are more frequently and extensively calcified. Annular calcifications were found in the crural arteries of CLI patients while dot-like calcifications were mostly present in non-PAD patients. These different patterns of calcifications in CLI point at different etiology and can have prognostic and eventually therapeutic consequences.

The Influence of Aortic Wall Elasticity on the False Lumen in Aortic Dissection: An In Vitro Study.

BACKGROUND: Hemodynamics, dissection morphology, and aortic wall elasticity have a major influence on the pressure in the false lumen. In contrast to aortic wall elasticity, the influence of hemodynamics and dissection morphology have been investigated often in multiple in vitro and ex vivo studies. The purpose of this study was to evaluate the influence of aortic wall elasticity on the diameter and pressure of the false lumen in aortic dissection. METHODS: An artificial dissection was created in 3 ex vivo porcine aortas. The aorta models were consecutively positioned in a validated in vitro circulatory system with physiological pulsatile flow. Each model was imaged with ultrasound on 4 positions along the aorta and the dissection. At these 4 locations, pressure measurement was also performed in the true and false lumen with an arterial catheter. After baseline experiments, the aortic wall elasticity was adjusted with silicon and the experiments were repeated. RESULTS: The aortic wall elasticity was decreased in all 3 models after siliconizing. In all 3 siliconized models, the diameters of the true and false lumen increased at proximal, mid, and distal location, while the mean arterial pressure did not significantly change. CONCLUSIONS: In this in vitro study, we showed that aortic wall elasticity is an important parameter altering the false lumen. An aortic wall with reduced elasticity results in an increased false lumen diameter in the mid and distal part of the false lumen. These results can only be transferred to corresponding clinical situations to a limited extent.

CT calcification patterns of peripheral arteries in patients without known peripheral arterial disease.

PURPOSE: In the last few years histologic studies of peripheral arteries have shown that both intimal and medial calcifications are found in patients in an early, asymptomatic stage and that differentiation between medial and intimal calcifications is possible. The aim of this study was to assess the computed tomography (CT) calcification characteristics in peripheral arteries and to explore potential patterns in subjects without peripheral arterial disease (PAD). METHOD: Retrospectively, 204 patients without known PAD were studied. The thin slice CT-imaging characteristics severity, annularity, thickness and continuity were scored in the following arteries: plantar and dorsal, crural, femoro-popliteal, iliac and the abdominal aorta. Interrelation was assessed using linear regression and significance was tested by Chi-Square tests. RESULTS: In the crural arteries two calcification patterns with strong associations were found. Pattern 1: continuous-annular 93.5 % (29/31), continuous-thin and thin-annular both 73 % (27/37, p < 0.001) and pattern 2: thick-discontinuous 91.7 % (44/48), thick-dotted 68.8 % (33/48), patchy-dotted 59.3 % (16/27, p < 0.001). Similar associations were found in the femoro-popliteal artery, but not in the plantar, dorsal, iliac arteries and aorta. CONCLUSIONS: In the crural and femoropopliteal arteries at least two morphological patterns can be distinguished on CT that, compared to a CT-histologically validated score, may represent an intimal and medial calcification pattern.

Cost-Effectiveness of Drug-Eluting Stents for Infrapopliteal Lesions in Patients with Critical Limb Ischemia: The PADI Trial.

PURPOSE: Drug-eluting stents (DES) improve clinical and morphological long-term results compared to percutaneous transluminal angioplasty (PTA) with bailout bare metal stenting (BMS) in patients with critical limb ischemia (CLI) and infrapopliteal lesions (PADI trial). We performed a cost-effectiveness analysis of DES compared to PTA ± BMS in cooperation with Dutch health insurance company VGZ, using data from the PADI trial. MATERIALS AND METHODS: In the PADI trial, adults with CLI (Rutherford category ≥ 4) and infrapopliteal lesions were randomized to receive DES with paclitaxel or PTA ± BMS. Seventy-four limbs (73 patients) were treated with DES and 66 limbs (64 patients) with PTA ± BMS. The costs were calculated by using the mean costs per stent multiplied by the mean number of stents used per patient (€750 × 1.8 for DES vs €250 × 0.3 for PTA ± BMS). These costs were compared with the costs of major amputation (€16.000) and rehabilitation (first year €15.750, second year €7.375 and third year €3.600). RESULTS: The 5-year major amputation rate was lower in the DES group (19.3% vs 34.0% for PTA ± BMS; p = 0.091). In addition, the 5-year amputation-free survival and event-free survival were significantly higher in the DES group (31.8% vs 20.4%, p=0.043; and 26.2% vs 15.3%, p=0.041, respectively). After 1 year, the cost difference per patient between DES and PTA ± BMS is €1.679 in favor of DES and €2.694 after 3 years. CONCLUSION: In our analysis, DES are cost-effective due to the higher hospital costs of amputation and rehabilitation in the PTA ± BMS group. LEVEL OF EVIDENCE: Level 1b, analysis based on clinically sensible costs and randomized controlled trial.

10-Year Paclitaxel Dose-Related Outcomes of Drug-Eluting Stents Treated Below the Knee in Patients with Chronic Limb-Threatening Ischemia (The PADI Trial).

PURPOSE: Recently, two meta-analyses concluded that there appears to be an increased risk of long-term mortality of paclitaxel-coated balloons and stents in the superficial femoral and popliteal artery, and paclitaxel-coated balloons below the knee. In this post hoc study of the PADI Trial, we investigated the long-term safety of first-generation paclitaxel-coated drug-eluting stents (DES) below the knee and the dose-mortality relationships of paclitaxel in patients with chronic limb-threatening ischemia (CLI). MATERIALS AND METHODS: The PADI Trial compared paclitaxel-coated DES with percutaneous transluminal angioplasty with bail-out bare-metal stents (PTA ± BMS) in patients with CLI treated below the knee. Follow-up was extended to 10 years after the first inclusion, and survival analyses were performed. In addition, dose-related mortality and dose per patient weight-related mortality relations were examined. RESULTS: A total of 140 limbs in 137 patients were included in the PADI Trial. Ten years after the first inclusion, 109/137 (79.6%) patients had died. There was no significant difference between mortality in the DES group compared with the PTA ± BMS group (Log-rank p value = 0.12). No specific dose-related mortality (HR 1.00, 95% CI 0.99-1.00, p = 0.99) or dose per weight mortality (HR 1.05, 95% CI 0.93-1.18, p = 0.46) relationships were identified in the Cox-proportional Hazard models or by Kaplan-Meier survival analyses. CONCLUSIONS: There is a poor 10-year survival in both paclitaxel-coated DES and PTA ± BMS in patients with CLI treated below the knee. No dose-related adverse effects of paclitaxel-coated DES were observed in our study of patients with CLI treated below the knee. LEVEL OF EVIDENCE: The PADI Trial: level 1, randomized clinical trial.

[Diagnostic Image. A woman with abdominal pain]. / Een vrouw met buikpijn.

A woman had abdominal pain due to ischaemia of the small intestine. This was probably caused by torsion due to pandiverticulosis.