Predictive Value of Laboratory Indicators for Endoleak During Short-Term Follow-Up After EVAR.

BACKGROUND: The aim of this study was to explore the predictive value of endoleak in short-term follow-up after endovascular aortic repair (EVAR) of abdominal aortic aneurysm (AAA) via perioperative laboratory indicators. METHODS: A retrospective study included 200 consecutive patients who received standard EVAR treatment for AAA and were followed-up for 1 year. Binary logistic regression analysis was used to evaluate the correlation of the level and changes of perioperative laboratory indicators with the endoleak events during the follow-up. The receiver operating characteristic (ROC) curve was used to assess the predictive value of laboratory indicators for endoleak. RESULTS: A total of 45 cases of endoleak events occurred during follow-up. Binary logistic regression analysis showed that postoperative fibrinogen decrease, perioperative lymphocyte difference and lymphocyte monocyte ratio (LMR) difference were independent risk factors for short term endoleak. The area under the ROC curve (AUC) of postoperative fibrinogen was 0.596, the cut-off value was 284 mg/dl, and the corresponding specificity and sensitivity were 0.644 and 0.568. The AUC of the lymphocyte difference was 0.622, the cut-off value was -0.45 × 109/L, and the corresponding specificity and sensitivity were 0.651 and 0.568. The AUC of the LMR difference was 0.597, the cut-off value was -1.719, and the corresponding specificity and sensitivity were 0.631 and 0.614. CONCLUSIONS: Decrease of postoperative fibrinogen, increase of lymphocyte difference and LMR difference were independent predictive factors for endoleak in short-term follow-up after EVAR for AAA.

Angiosarcoma after endovascular aneurysm repair: case report and literature review.

INTRODUCTION: Epithelioid angiosarcoma is a rare soft tissue sarcoma with a poor prognosis. We report two cases of patients who presented with a history of lower back pain, inflammatory signs and weight loss 5 and 6 years after endovascular aortic repair (EVAR) of an elective infrarenal abdominal aortic aneurysm (AAA). Imaging suggested graft infection but tissue samples revealed an epithelioid angiosarcoma. The objective is to report the clinical presentation, investigative modalities and immunohistochemical findings of an angiosarcoma after EVAR. PATIENTS AND METHODS: Two cases are described of an angiosarcoma of the aorta after EVAR. A literature search using PubMed, Embase and Web of Science was performed in English about angiosarcoma after EVAR published between 2007 and 2021. Relevant reports were selected and analysed. RESULTS: Fifteen case reports were identified, including the current two cases. Time to tumour detection after EVAR ranged from 6 to 120 months with a mean interval of 68 months. Most patients underwent endovascular repair of an AAA (13/15). Males (13 male/2 female patients) were predominant with a median age of 72 years (IQR 68-78 years). Over half of the patients had metastases at the time of diagnosis (9/15), most frequently in bones and liver. CONCLUSION: Diagnosis of angiosarcoma after EVAR remains challenging due to indistinctive clinical and radiological findings mimicking graft infection or endoleak. Angiosarcoma should be included in the differential diagnosis in patients previously treated with EVAR presenting with unintended weight loss, abdominal back pain and contrast enhancement of the aortic wall.AbbreviationsAAAabdominal aortic aneurysmCTAcomputed tomography angiographyCRPc-reactive proteinEVARendovascular aortic repairESRerythrocyte sedimentation rateFDGfluoro-deoxyglucoseMRImagnetic resonance imagingMeSHmedical subject headings.

[Endoleaks in endovacular treatment of infrareneral abdominal aortic aneurysm (part I)]. / Endoliki pri endovaskulyarnom protezirovanii infrarenal'noi anevrizmy bryushnoi aorty (chast' I).

We analyzed the PubMed, Scopus databases and the eLIBRARY electronic library regarding appropriate literature data. In the first part, modern classifications of endoleaks type 1 and 2 after stenting of infrarenal aortic aneurysm are considered. We described causes, risk factors and effectiveness of various treatment options.

[Endovascular aortic repair of endoleaks : Diagnosis, treatment, and outcomes]. / Endovaskuläre Aortenreparatur bei Endoleaks : Diagnose, Behandlung und Ergebnisse.

All patients who underwent endovascular aortic repair (EVAR) need a thorough follow-up, at least yearly. Contrast-enhanced ultrasound and computed tomography angiography (CTA) are the most important modalities for detection of endoleaks, whereby CTA allows better differentiation of endoleak type. High pressure endoleaks (type I and III) are an absolute indication for treatment if they do not resolve spontaneously in the short term. Type II endoleaks are mostly benign and may be routinely controlled if there is no progression of the aneurysm. Type II endoleaks associated with aneurysm progression may be treated with embolization; however, whether they must be treated is a matter of discussion. Nonetheless, a type II endoleak must be treated when progression shortens the aneurysm neck and the threat of a type I endoleak is at hand. Type I endoleaks are the main limitation of stent grafts. An adequate proximal landing zone is the best prevention for type I endoleaks, even if fenestrated stent grafts have to be used. Various fixation devices for short necks are currently under investigation.

An unusual cause of failure in Zenith Alpha Abdominal endograft.

BACKGROUND: Graft disruption is an unusual complication of the endovascular abdominal aortic aneurysm repair (EVAR). CASE PRESENTATION: A 71-year-old man underwent standard EVAR with Zenith Alpha Abdominal endograft. Follow-up examinations revealed an initial significant sac shrinkage. At 24 months, duplex ultrasound (DUS) scan and computed tomography showed increase of the sac diameter associated with complete disconnection of the suprarenal stent-graft from the main body without evidence of endoleak. A standard relining with a thoracic endograft was performed between the suprarenal stent and the main body of the previous graft. At 6 months DUS revealed sac shrinkage. CONCLUSIONS: This report demonstrates an uncommon cause of endograft failure with suprarenal stent disconnection from main body and highlights the need for continuous follow-up in patients undergoing EVAR.

Predictors of sac regression after fenestrated endovascular aneurysm repair.

OBJECTIVE: Aneurysm sac regression after standard endovascular aortic repair is associated with improved outcomes, but similar data are limited after fenestrated endovascular aortic repair (FEVAR). We sought to evaluate sac regression after FEVAR, and identify any predictors of this favorable outcome. METHODS: Patients undergoing elective FEVAR using the commercially available Zenith Fenestrated device (ZFEN; Cook Medical, Bloomington, IN) from 2012 to 2018 at a single institution were reviewed retrospectively. The maximal aortic diameter was compared between the preoperative scan and those obtained in follow-up. Patients with of 5 mm or more sac regression were included in the regression (REG) group, with all others in the nonregression (NONREG) group. Outcomes were compared between groups using univariate analysis, and logistic regression analysis was performed to identify any predictive factors for sac regression. RESULTS: We included 132 patients undergoing FEVAR in the analysis. At a mean follow-up of 33.1 months, 65 patients (49.2%) had sac regression of 5 mm or more and comprised the REG group (n = 65 [49.2%]). The REG group had smaller diameter devices, and were less likely to have had concomitant chimney grafts placed (P < .05). The NONREG group had a higher incidence of type II endoleak (35.8% vs 12.3%; P = .002). Sac regression was associated with a significant mortality benefit on Kaplan-Meier analysis (log rank P = .02). Multivariate analysis identified adjunctive parallel grafting (odds ratio [OR], 0.01; 95% confidence interval [CI], 0.03-0.36; P < .01), persistent type II endoleak (OR, 0.13; 95% CI, 0.02-0.74; P < .01), and a greater number of target vessels (OR, 0.25; 95% CI, 0.10-0.62; P = .002) as independent predictors of failure to regress. CONCLUSIONS: Sac regression after FEVAR occurred in nearly one-half of patients, but seems to be less common in patients with persistent type II endoleaks and those undergoing concomitant parallel grafting. Sac regression was associated with a significant survival advantage, and can be used as a clinical marker for success after FEVAR.

Long-term outcomes and interventions of postoperative type 1a endoleak following elective endovascular aortic aneurysm repair.

OBJECTIVE: This study evaluated the incidence and long-term outcomes of postoperative type 1a endoleak (PT1a) following endovascular aortic aneurysm repair (EVAR). METHODS: A retrospective review of consecutive aortoiliac EVARs performed at a single institution from June 2006 to June 2012 was conducted. Patients with PT1a were identified by postoperative imaging and compared with those who did not develop a PT1a. Late outcomes were also studied of a subset of patients with PT1a who had persistent intraoperative type 1a endoleak (iT1a) on completion angiogram during EVAR that had resolved on initial follow-up imaging. RESULTS: Three hundred eighty-nine patients underwent EVAR with median follow-up of 87 months (interquartile range, 64-111 months). The incidence of PT1a was 8.2% (n = 32) with a median follow-up of 74 months (interquartile range, 52-138 months). Compared with the total cohort, those who developed PT1a were statistically more likely to be female (32% vs 17%; P = .03) and have a higher all-cause mortality (71% vs 40%; P < .01) and aneurysm-related mortality (15.6% vs 1.7%; P < .01). Median time to presentation was 52 months. Of the 32 patients with PT1a, five (15.6%) presented with aortic rupture, of which three underwent extension cuff placement, one had open graft explant, and one declined intervention. Six patients in total (18.7%) declined intervention; five of these died of nonaneurysmal causes and one remains alive. Of the 26 patients with PT1a who had intervention, 21 (80.7%) showed resolution of PT1a, and five (19.2%) had recurrence. For patients with recurrent PT1a, two had resulting aneurysm-related mortality, two endoleaks resolved after relining with an endograft, and one patient declined intervention but remains alive. Patients with PT1a who had intervention with resolution showed no significant difference in median survival estimates (140.0 months) compared with the remaining EVAR cohort (120.0 months; P = .80). Within the PT1a cohort, 6 (18.7%) had also experienced iT1a with a mean time to presentation of the late PT1a of 45 months. iT1a was associated with a significantly increased likelihood of developing a PT1a (P < .01) and decreased median survival (P < .01), but there was no known aneurysm-related mortality. CONCLUSIONS: Development of PT1a following elective EVAR is associated with increased all-cause and aneurysm-related mortality and presents an average of 52 months postoperatively. This underscores the importance of long-term surveillance. Patients with PT1a who had a successful intervention showed no significant difference in median survival. Those with iT1a had a higher risk for PT1a compared with the EVAR cohort overall and had decreased median survival, without increased aneurysm-related mortality.

Surgical Findings and Outcomes of Endotension Following Endovascular Aneurysm Repair.

BACKGROUND: Endotension is one of the detrimental complications after endovascular aneurysm repair (EVAR) and surgical management has been considered as standard of care. However, there is a paucity of data regarding the findings, and outcomes of such surgical intervention. The aim of this study was to investigate intraoperative findings and outcomes of surgical treatment for endotension after EVAR. METHODS: Between January 2005 and October 2018, of the 708 patients who underwent EVAR for aneurysm aortic aneurysm; 12 patients (mean age of 76.1; range 66-88) who underwent open repair for endotension were retrospectively analyzed. The anatomical characteristics of the aorta and surgical findings were reviewed. The rates of early and late procedural complications, and overall mortality were evaluated. RESULTS: The median interval between the EVAR and surgical conversion was 45.9 months (range 17.1-46.9). Three of the twelve patients underwent emergency surgery due to aneurysm rupture. The median aneurysm sac size, the proximal neck diameter, and the proximal neck length before EVAR were 64 mm, 23.5 mm, and 30.5 mm, respectively, that changed before open repair to 93.5 mm (P = 0.02), 25 mm (P = 0.011), and 23 mm (P = 0.003), respectively. In four of the twelve patients, radiographically undetected endoleak was identified during surgery to be Type Ia, Ib, II, and III, respectively. The rates of early and late procedural complications, and overall mortality were 8.3%, 8.3% and 8.3%, respectively. CONCLUSIONS: Patients with endotension have a risk of delayed endoleak and aneurysm rupture; secondary intervention should be performed in such cases to prevent fatal complications. Surgical treatment appears to be a curative treatment for endotension with favorable outcomes. In addition, the possibility of an undetected endoleak should be considered as a potential cause of endotension.

Late Type 1A Endoleaks: Associated Factors, Prognosis and Management Strategies.

BACKGROUND: Unlike periprocedural Type 1A endoleaks, late appearing proximal endoleaks have been poorly described. METHODS: We studied all elective EVAR from 2010 -2018 in a single institution. Late endoleaks were defined as those appearing after 1 year. We used Cox regression to study factors associated with late Type 1A endoleaks and survival. RESULTS: Of 477 EVAR during the study period, 411 (86%) had follow-up imaging, revealing 24 Type 1A endoleaks; 4 early and 20 late. Freedom from Type 1A endoleaks was 99%, 92-81% at 1, 5 and 8 years with a median time to occurrence of 2.5 years (.01-8.2 years). On completion angiogram, only 10% of patients with a late Type 1A had a proximal endoleak, and 60% had no endoleak. Only 21% of late Type 1As were diagnosed on routine 1-year CT angiogram, but 79% had stable or expanding sacs. Two thirds (65%) of the patients eventually diagnosed with late Type 1A endoleaks had previously been treated for other endoleaks, mostly Type 2 (10/13). Age (HR 1.07/year [1.02-1.12], P = 0.01), neck diameter >28mm (HR 3.5 [1.2-10.3], P = 0.02), neck length <20mm (HR 3.0 [1.1-8.6], P = 0.04), and neck angle>60 degrees (HR 3.4 [1.5-7.9], P = 0.004) were associated with higher rates of Type 1A endoleak, but not female sex, endograft, or the use of suprarenal fixation. 2 patients had proximal degeneration and 5 experienced graft migration. There were 2 ruptures (10%), and 13 patients underwent repair with 5 open conversions. Median survival after late Type 1A repair was 6.6 years (0-8.4 years). CONCLUSION: Late appearing Type 1A endoleaks have a high rate of rupture and present significant diagnostic and management challenges. Careful surveillance is needed in patients with hostile neck anatomy and those who undergo intervention for other endoleaks. Adverse neck anatomy may be better suited for open repair or fenestrated/branched devices rather than conventional EVAR.

Risk Factors, Dynamics, and Clinical Consequences of Aortic Neck Dilatation after Standard Endovascular Aneurysm Repair.

OBJECTIVE: Aortic neck dilatation (AND) occurs after endovascular aneurysm repair (EVAR) with self expanding stent grafts (SESs). Whether it continues, ultimately exceeding the endograft diameter leading to abdominal aortic aneurysm (AAA) rupture, remains uncertain. Dynamics, risk factors, and clinical relevance of AND were investigated after EVAR with standard SESs. METHODS: All intact EVAR patients treated from 2000 to 2015 at a tertiary institution were included. Demographic, anatomical, and device related characteristics were investigated as risk factors for AND. Outer to outer diameters were measured at a single standardised aortic level on reconstructed computed tomography (CT) images. RESULTS: A total of 460 patients were included (median follow up 5.2 years, interquartile range [IQR] 3.0, 7.7 years; CT imaging follow up 3.3 years, IQR 1.3, 5.4). Baseline neck diameter was 24 mm (IQR 22, 26) and increased 11.1% (IQR 1.5%, 21.9%) at last CT imaging. Endograft oversizing was 20.0% (IQR 13.6, 28.0). AND was greater during the first year (5.2% [IQR 0, 11.7]) decreasing subsequently (two to four years to 1.4%/year [IQR 0.0, 4.5%], p ≤ .001) and was associated with suprarenal fixation endografts (t value = 7.9, p < .001) and oversizing (t value = 4.4, p < .001). AND exceeding the endograft was 3.5% (95% CI 2.2% - 4.8%) and 14.4% (95% CI 11.0% - 17.8%) at five and eight years, respectively. Excessive AND was associated with baseline neck diameter (OR 1.2/mm, 95% CI 1.05 - 1.41) while the Excluder endograft had a protective effect (OR 0.15, 95% CI 0.04 - 0.58). Excessive AND was associated with type 1A endoleak (HR 3.3, 95% CI 1.1 - 9.7) and endograft migration > 5 mm (HR 3.1, 95% CI 1.4 - 6.9). CONCLUSION: AND after EVAR with SES is associated with endograft oversizing and radial force but decelerates after the first post-operative year. Baseline aortic neck diameter and suprarenal stent bearing endografts were associated with an increased risk of AND beyond nominal stent graft diameter. However, it remains unclear whether patient selection, differences in endograft radial force or the suprarenal stent are accountable for this difference.

Laparoscopic lumbar artery ligation of type II endoleaks following endovascular aneurysm repair: A case report.

INTRODUCTION: Although the clinical significance of type II endoleaks remain controversial, management strategies continue to expand. The laparoscopic approach is a minimally invasive method for persistent type II endoleak repair after endovascular aneurysm repair. PATIENT CONCERNS: A 70 - year - old male patient with a history of endovascular aneurysm repair with left internal iliac artery embolization presented with persistent type II endoleak from the lumbar arteries 2 years ago. The aneurysm sac size had increased more than 10 mm during follow up period. DIAGNOSIS: Persistent type II endoleak after endovascular aneurysm repair. INTERVENTIONS: Transarterial embolization was attempted and failed. A minimally invasive laparoscopic lumbar artery ligation was then utilized. OUTCOMES: The patient was discharged without any complications after surgery. Follow-up computed tomography angiography has shown the complete disappearance of the type II endoleaks. CONCLUSIONS: Laparoscopic lumbar artery ligation may be a safe and effective alternative treatment for type II endoleaks, especially in high resource settings.

Evaluation of Zone 2 Thoracic Endovascular Aortic Repair Performed with and without Prophylactic Embolization of the Left Subclavian Artery in Patients with Traumatic Aortic Injury.

OBJECTIVE: To report the authors' experience in performing thoracic endovascular aortic repair (TEVAR) for zone 2 lesions after traumatic aortic injury (TAI). MATERIALS AND METHODS: This retrospective review included 10 patients who underwent zone 2 TEVAR after identification of aortic isthmus injury by CT angiography (CTA) upon arrival at the emergency room of a regional trauma center from 2016 to 2019. Patients were classified into two groups: those who underwent left subclavian artery (LSA) embolization concurrently with the main TEVAR procedure, and those in whom LSA embolization was not performed during the main procedure, but was planned as a bailout treatment if type II endoleak was noted on follow-up CTA images. Pre-procedural and procedure-related factors and post-procedure prognosis were compared between the groups. RESULTS: There were no differences in pre-procedural factors, occurrence of endoleaks, and post-procedure prognosis (including mortality) between patients in the two groups. The duration of the procedure was shorter in the non-LSA embolization group (61 minutes vs. 27 minutes, p = 0.012). During follow-up, type II endoleak did not occur in either group. CONCLUSION: Delaying preventative LSA embolization until stabilization of the patient would be desirable when performing zone 2 TEVAR for TAI, in the absence of endoleak on the completion aortography image taken after complete deployment of the stent graft.

Utility of Noncontrast Magnetic Resonance Angiography for Aneurysm Follow-Up and Detection of Endoleaks after Endovascular Aortic Repair.

OBJECTIVE: To assess the noncontrast two-dimensional single-shot balanced turbo-field-echo magnetic resonance angiography (b-TFE MRA) features of the abdominal aortic aneurysm (AAA) status following endovascular aneurysm repair (EVAR) and evaluate to detect endoleaks (ELs). MATERIALS AND METHODS: We examined four aortic stent-grafts in a phantom study to assess the degree of metallic artifacts. We enrolled 46 EVAR-treated patients with AAA and/or common iliac artery aneurysm who underwent both computed tomography angiography (CTA) and b-TFE MRA after EVAR. Vascular measurements on CTA and b-TFE MRA were compared, and signal intensity ratios (SIRs) of the aneurysmal sac were correlated with the size changes in the AAA after EVAR (AAA prognoses). Furthermore, we examined six feasible b-TFE MRA features for the assessment of ELs. RESULTS: There were robust intermodality (r = 0.92-0.99) correlations and interobserver (intraclass correlation coefficient = 0.97-0.99) agreement. No significant differences were noted between SIRs and aneurysm prognoses. Moreover, "mottled high-intensity" and "creeping high-intensity with the low-band rim" were recognized as significant imaging findings suspicious for the presence of ELs (p < 0.001), whereas "no signal black spot" and "layered high-intensity area" were determined as significant for the absence of ELs (p < 0.03). Based on the two positive features, sensitivity, specificity, and accuracy for the detection of ELs were 77.3%, 91.7%, and 84.8%, respectively. Furthermore, the k values (0.40-0.88) displayed moderate-to-almost perfect agreement. CONCLUSION: Noncontrast MRA could be a promising imaging modality for ascertaining patient follow-up after EVAR.

Society for Vascular Surgery clinical practice guidelines of thoracic endovascular aortic repair for descending thoracic aortic aneurysms.

Thoracic aortic diseases, including disease of the descending thoracic aorta (DTA), are significant causes of death in the United States. Open repair of the DTA is a physiologically impactful operation with relatively high rates of mortality, paraplegia, and renal failure. Thoracic endovascular aortic repair (TEVAR) has revolutionized treatment of the DTA and has largely supplanted open repair because of lower morbidity and mortality. These Society for Vascular Surgery Practice Guidelines are applicable to the use of TEVAR for descending thoracic aortic aneurysm (TAA) as well as for other rarer pathologic processes of the DTA. Management of aortic dissections and traumatic injuries will be discussed in separate Society for Vascular Surgery documents. In general, there is a lack of high-quality evidence across all TAA diseases, highlighting the need for better comparative effectiveness research. Yet, large single-center experiences, administrative databases, and meta-analyses have consistently reported beneficial effects of TEVAR over open repair, especially in the setting of rupture. Many of the strongest recommendations from this guideline focus on imaging before, during, or after TEVAR and include the following: In patients considered at high risk for symptomatic TAA or acute aortic syndrome, we recommend urgent imaging, usually computed tomography angiography (CTA) because of its speed and ease of use for preoperative planning. Level of recommendation: Grade 1 (Strong), Quality of Evidence: B (Moderate). If TEVAR is being considered, we recommend fine-cut (≤0.25 mm) CTA of the entire aorta as well as of the iliac and femoral arteries. CTA of the head and neck is also needed to determine the anatomy of the vertebral arteries. Level of recommendation: Grade 1 (Strong), Quality of Evidence: A (High). We recommend routine use of three-dimensional centerline reconstruction software for accurate case planning and execution in TEVAR. Level of recommendation: Grade 1 (Strong), Quality of Evidence: B (Moderate). We recommend contrast-enhanced computed tomography scanning at 1 month and 12 months after TEVAR and then yearly for life, with consideration of more frequent imaging if an endoleak or other abnormality of concern is detected at 1 month. Level of recommendation: Grade 1 (Strong), Quality of Evidence: B (Moderate). Finally, based on our review, in patients who could undergo either technique (within the criteria of the device's instructions for use), we recommend TEVAR as the preferred approach to treat elective DTA aneurysms, given its reduced morbidity and length of stay as well as short-term mortality. Level of recommendation: Grade 1 (Strong), Quality of Evidence: A (High). Given the benefits of TEVAR, treatment using a minimally invasive approach is largely based on anatomic eligibility rather than on patient-specific factors, as is the case in open TAA repair. Thus, for isolated lesions of the DTA, TEVAR should be the primary method of repair in both the elective and emergent setting based on improved short-term and midterm mortality as well as decreased morbidity.

Cost-effectiveness of contrast-enhanced ultrasound for the detection of endovascular aneurysm repair-related endoleaks requiring treatment.

OBJECTIVE: Follow-up after endovascular aneurysm repair is necessary to detect potentially life-threatening complications such as endoleaks. Computed tomography angiography (CTA) or magnetic resonance angiography (MRA) is often used as standard of care for follow-up. Contrast-enhanced ultrasound (CEUS) has been shown to be a viable and fast real-time nonionizing imaging modality with equivalent diagnostic accuracy while also being superior to color Doppler ultrasound. The aim of this cost-utility analysis was to evaluate the cost-effectiveness of this imaging method in comparison to others for the evaluation of endoleaks requiring treatment. METHODS: A decision model based on Markov simulations estimated lifetime costs and quality-adjusted life years (QALYs) associated with CTA, MRA, CEUS, and color Doppler ultrasound. Model input parameters were obtained from recent literature. The applied sensitivity and specificity values amounted to 90.5% and 100.0% for CTA, 96.0% and 100.0% for MRA, 94.0% and 95.0% for CEUS, and 82.0% and 93.0% for color Doppler ultrasound. Probabilistic and deterministic sensitivity analysis was performed to estimate uncertainty of model results. To evaluate cost-effectiveness, incremental cost-effectiveness ratios were reported as a measure representing the economic value of a strategy compared with an alternative. The willingness to pay was set to $100,000/QALY. RESULTS: In the base-case scenario for a willingness to pay of $100,000 per QALY, CEUS was the most cost-effective of the four diagnostic strategies with estimated costs of $17,383 and effectiveness of 9.770 QALYs. CTA was estimated to result in lifetime costs of $17,679 with an expected effectiveness of 9.768 QALYs, whereas color Doppler ultrasound showed expected costs of $17,287 with 9.763 QALYs. Expected costs and effectiveness of MRA amounted to $17,945 and 9.771 QALYs each. Base-case estimates of the incremental cost-effectiveness ratios for CEUS vs color Doppler ultrasound equaled $14,173.52/QALY. CONCLUSIONS: CEUS is a cost-effective imaging method for the evaluation of therapy-requiring endoleaks in endovascular aneurysm repair surveillance.

The association between perioperative embolization of hypogastric arteries and type II endoleaks after endovascular aortic aneurysm repair.

OBJECTIVE: Type II endoleaks (T2ELs) are the most common type of endoleak after endovascular aneurysm repair (EVAR). The iliolumbar artery arising from the hypogastric artery is often a major source of T2ELs, and transarterial embolization of the iliolumbar artery through the hypogastric artery is sometimes performed to interrupt sac expansion during follow-up. Considering the equivocal results of an association between hypogastric embolization and T2ELs in previous studies, this topic has re-emerged after the advent of iliac branch devices. This study reviewed our series to clarify whether hypogastric embolization is associated with T2ELs at 12 months after EVAR. METHODS: Patients who underwent elective EVAR between June 2007 and May 2017 at our institution were retrospectively reviewed. Patients with postoperative computed tomography angiography (CTA) at 12 months were included. Patients in whom CTA revealed type I or type III endoleaks during follow-up, who required reinterventions before 12 months, and who had solitary iliac aneurysms were excluded. The primary outcome was the incidence of T2ELs at 12 months after EVAR. The associations of patients' characteristics, anatomic factors, hypogastric embolization, and type of endograft with the primary outcome were analyzed. RESULTS: In total, 375 patients were enrolled. During the median follow-up of 59.5 months (interquartile range, 19-126 months), 40 patients died, and 50 reinterventions were performed. In 108 patients (28.8%), either hypogastric artery was embolized to extend distal landings to the external iliac artery. Bilateral and unilateral embolization was performed in nine and 99 patients, respectively. In total, 153 patients (40.8%) had T2ELs found by CTA at 12 months. In the univariate analysis, the status of hypogastric artery occlusion or embolization was not significantly different between patients with and without T2ELs. However, there were not enough patients to detect a 10% difference in T2ELs with >80% statistical power. In the multivariate analysis, significant associations with T2EL were observed for female sex (P = .049), patent inferior mesenteric artery (P = .006), and presence of five or more patent lumbar arteries (P < .001) but not for hypogastric embolization. In addition, compared with the Zenith (Cook Medical, Bloomington, Ind) endograft, the Excluder (W. L. Gore & Associates, Flagstaff, Ariz) endograft was significantly related to T2EL (P = .001). CONCLUSIONS: No significant association between hypogastric embolization and T2EL was demonstrated in this retrospective study, which lacked adequate statistical power.

Prediction, pattern recognition and modelling of complications post-endovascular infra renal aneurysm repair by artificial intelligence.

OBJECTIVES: The study evaluates the plausibility and applicability of prediction, pattern recognition and modelling of complications post-endovascular aneurysm repair (EVAR) by artificial intelligence for more accurate surveillance in practice. METHODS: A single-centre prospective data collection on (n = 250) EVAR cases with n = 26 preoperative attributes (factors) on endpoint of endoleak (types I-VI), occlusion, migration and mortality over a 13-year period was conducted. In addition to the traditional statistical analysis, data was subjected to machine learning algorithm through artificial neural network. The predictive accuracy (specificity and -1 sensitivity) on each endpoint is presented with percentage and receiver operative curve. The pattern recognition and model classification were conducted using discriminate analysis, decision tree, logistic regression, naive Bayes and support vector machines, and the best fit model was deployed for pattern recognition and modelling. RESULTS: The accuracy of the training, validation and predictive ability of artificial neural network in detection of endoleak type I was 95, 96 and 94%, type II (94, 83, 90 and 82%) and type III was 96, 94 and 96%, respectively. Endpoints are associated with increase in weights through predictive modeling that were not detected through statistical analytics. The overall accuracy of the model was >86%. CONCLUSION: The study highlights the applicability, accuracy and reliability of artificial intelligence in the detection of adverse outcomes post-EVAR for an accurate surveillance stratification.

Artifacts in Contrast-Enhanced Ultrasound during Follow-up after Endovascular Aortic Repair: Impact on Endoleak Detection in Comparison with Computed Tomography Angiography.

The study described here systematically analyzed how specific artifacts in contrast-enhanced ultrasound (CEUS) can affect the detection of endoleaks during follow-up after endovascular aortic repair (EVAR). Patients undergoing EVAR of atherosclerotic or mycotic abdominal aortic aneurysms using various standard and branched stent-graft material for visceral and iliac preservation were enrolled over 5 y and followed up with computed tomography angiography (CTA) and CEUS simultaneously. CEUS artifacts were frequently identified after EVAR procedures (59% of examinations) and were caused mainly by contrast agent, different prosthesis or embolization material and postinterventional changes in the aneurysm sac. This article describes how to identify important artifacts and how to avoid false-negative or false-positive interpretations of endoleaks. Despite artifacts, CEUS had higher sensitivity for endoleak detection after EVAR than CTA. CEUS was superior to CTA in the identification of late endoleaks type II and in follow-up examinations after embolization procedures, where beam-hardening artifacts limited CTA.

Vascular plug oversizing to treat an endoleak after hybrid surgery of the aortic arch.

A patient with prior ascending aortic replacement for a type A acute dissection and a bovine arch presented with an asymptomatic chronic dissecting innominate artery aneurysm extending to both carotid arteries. As the patient refused redo open surgery, we performed a hybrid procedure with reverse extra-anatomic aortic arch debranching and a fenestrated endograft. The aneurysm was still partially perfused due to an endoleak and corrected 1 week later with vascular plugs.

Machine learning for endoleak detection after endovascular aortic repair.

Diagnosis of endoleak following endovascular aortic repair (EVAR) relies on manual review of multi-slice CT angiography (CTA) by physicians which is a tedious and time-consuming process that is susceptible to error. We evaluate the use of a deep neural network for the detection of endoleak on CTA for post-EVAR patients using a novel data efficient training approach. 50 CTAs and 20 CTAs with and without endoleak respectively were identified based on gold standard interpretation by a cardiovascular subspecialty radiologist. The Endoleak Augmentor, a custom designed augmentation method, provided robust training for the machine learning (ML) model. Predicted segmentation maps underwent post-processing to determine the presence of endoleak. The model was tested against 3 blinded general radiologists and 1 blinded subspecialist using a held-out subset (10 positive endoleak CTAs, 10 control CTAs). Model accuracy, precision and recall for endoleak diagnosis were 95%, 90% and 100% relative to reference subspecialist interpretation (AUC = 0.99). Accuracy, precision and recall was 70/70/70% for generalist1, 50/50/90% for generalist2, and 90/83/100% for generalist3. The blinded subspecialist had concordant interpretations for all test cases compared with the reference. In conclusion, our ML-based approach has similar performance for endoleak diagnosis relative to subspecialists and superior performance compared with generalists.