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.

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.

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.

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.

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.

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.

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.

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.

Secondary Endoleak Management Following TEVAR and EVAR.

Endovascular abdominal and thoracic aortic aneurysm repair and are widely used to treat increasingly complex aneurysms. Secondary endoleaks, defined as those detected more than 30 days after the procedure and after previous negative imaging, remain a challenge for aortic specialists, conferring a need for long-term surveillance and reintervention. Endoleaks are classified on the basis of their anatomic site and aetiology. Type 1 and type 2 endoleaks (EL1 and EL2) are the most common endoleaks necessitating intervention. The management of these requires an understanding of their mechanics, and the risk of sac enlargement and rupture due to increased sac pressure. Endovascular techniques are the main treatment approach to manage secondary endoleaks. However, surgery should be considered where endovascular treatments fail to arrest aneurysm growth. This chapter reviews the aetiology, significance, management strategy and techniques for different endoleak types.

Type II endoleak with an enlarging aortic sac after endovascular aneurysm repair predisposes to the development of a type IA endoleak.

OBJECTIVE: The most common endoleak after endovascular aneurysm repair is type II. Although type II endoleaks (TIIEL) are generally considered benign, there are reports that they can lead to aortic rupture. In this study, we reviewed the effect of TIIEL on sac size change to determine if sac expansion owing to a TIIEL could result in the development of a type IA endoleak (TIAEL). METHODS: After internal review board approval, all aortoiliac endovascular aneurysm repairs performed at a single institution between June 2006 and June 2012 were retrospectively reviewed. Patient demographics, comorbidities, aneurysm diameter, graft type, need for reintervention, and complications were collected. Patients with TIIEL diagnosed on follow-up imaging were categorized as those who underwent intervention for their TIIEL and those who did not. Outcomes were tabulated with attention to sac size change, development of TIAEL, rupture, and survival. RESULTS: Six hundred twenty-seven patients underwent aortoiliac stent graft placement at our institution during this time period. Patients with an operative indication other than nonruptured infrarenal abdominal aortic aneurysm and those without preoperative computed tomography angiography or follow-up data available for review were excluded. The total number of patients included was 389 with an average follow-up of 58.8 months (range, 0-194 months). Follow-up imaging diagnosed 124 patients with TIIEL (32%). Patients with TIIEL were significantly older (P < .0001) and more likely to be hypertensive (P < .05) but less likely to be smokers (P = .01). They had a significantly larger sac size increase than patients without TIIEL (9.50 vs -0.78 mm; P < .0001). Those with TIIEL were significantly more likely to develop a TIAEL than patients who did not have TIIEL (14% vs 5%; P = .004), but the rate of rupture was not significantly different (4% vs 2%; P = .33). In those with a TIIEL, the average sac size increase at which TIAEL developed was 13 mm. Patients in the TIIEL group who underwent intervention for their TIIEL survived significantly longer than patients who did not undergo intervention (140 months vs 100 months; P = .004). CONCLUSIONS: Our data suggest that there is an increased incidence of late TIAEL in patients with TIIEL compared with those without a TIIEL. Our study also demonstrates an increased overall survival in TIIEL patients who underwent intervention. Future studies are necessary to better define the association between TIIEL with enlarging sac and the development of TIAEL. However, it is reasonable to conclude that intervention for TIIEL should be undertaken at or before a cumulative sac size increase of 13 mm.

Geometric and hemodynamic analysis of fenestrated and multibranched aortic endografts.

OBJECTIVE: The objective of this study was to determine the influence of hemodynamic force on the development of type III endoleak and branch thrombosis after complex endovascular thoracoabdominal aortic aneurysm repair. METHODS: Patients with thoracoabdominal aortic aneurysm, within surgical range, treated with a fenestrated or branched endovascular aneurysm repair from 2014 to 2018 and with 3-month control computed tomography angiography were selected. Demographic variables, aneurysm anatomy, and endograft conformation were analyzed retrospectively from a prospective registry. The hemodynamic force was calculated using the mass and momentum conservation equations. RESULTS: Twenty-eight patients were included; the mean follow-up period was 24.7 ± 19.3 months. There were 102 abdominal vessels successfully catheterized (19 celiac arteries, 29 superior mesenteric arteries, 27 right renal arteries, 26 left renal arteries, and 1 polar renal artery). The rate of type III endoleak was 11.5% (n = 12); six cases were associated with branches that received two stents (P < .001). A higher rate of endoleak was observed with wider stents (8.50 ± 1.0 mm vs 7.17 ± 1.3 mm; P = .001) but not with longer stents (P = .530). All cases of type III endoleak affected visceral arteries (eight celiac arteries and four superior mesenteric arteries). The freedom from type III endoleak at 24 months was 86%. The rate of thrombosis was 5.9% (n = 6). A higher rate of thrombosis was observed in smaller vessels (5.00 ± 1.3 mm vs 7.16 ± 1.8 mm; P = .001), with higher stent oversizing (36.87% ± 23.6% vs 5.52% ± 15.0%; P < .001), and with a higher angle of curvature (124.33 ± 86.1 degrees vs 57.71 ± 27.9 degrees; P < .001). All cases of thrombosis were related to renal arteries (two left renal arteries, two right renal arteries, and two polar renal arteries). The freedom from thrombosis at 24 months was 92%. The area under the curve for the angle of curvature was 0.802 (95% confidence interval, 0.661-0.943; P = .013), and the cutoff point was established at 59.5 degrees (sensitivity, 100%; specificity, 60.4%). The receiver operating characteristic curve for the stent oversize showed an area under the curve of 0.903 (95% confidence interval, 0.821-0.984; P = .001), and the cutoff point was 14.5% (sensitivity, 100%; specificity, 77.1%). A higher hemodynamic force was associated with thrombosis (23.35 × 10-3 N ± 18.7 × 10-3 N vs 12.31 × 10-3 N ± 6.8 × 10-3 N; P = .001) but not with endoleak (P = .796). The freedom from endoleak and thrombosis at 24 months was 86% and 90%, respectively. CONCLUSIONS: Longer stents should be preferred to avoid type III endoleak. A higher angle of curvature leads to a higher hemodynamic force that results in a higher rate of thrombosis. Accordingly, we recommend maintaining the angle of curvature under 59.9 degrees. Small vessels and excessive stent oversizing entail a higher risk of thrombosis; as such, we advise a maximum stent oversize of 14.5%. Renal arteries are more susceptible to thrombosis, whereas visceral arteries are more prone to endoleak.

Thoracic aortic geometry correlates with endograft bird-beaking severity.

OBJECTIVE: Aortic geometry has been shown to influence the development of endograft malapposition (bird-beaking) in thoracic endovascular aortic repair (TEVAR), but the extent of this relationship lacks clarity. The aim of this study was to develop a reproducible method of measuring bird-beak severity and to investigate preoperative geometry associated with bird-beaking. METHODS: The study retrospectively analyzed 20 patients with thoracic aortic aneurysms or type B dissections treated with TEVAR. Computed tomography scans were used to construct three-dimensional geometric models of the preoperative and postoperative aorta and endograft. Postoperative bird-beaking was quantified with length, height, and angle; categorized into a bird-beak group (BBG; n = 10) and no bird-beak group (NBBG; n = 10) using bird-beak height ≥5 mm as a threshold; and correlated to preoperative metrics including aortic cross-sectional area, inner curvature, diameter, and inner curvature × diameter as well as graft diameter and oversizing at the proximal landing zone. RESULTS: Aortic area (1002 ± 118 mm2 vs 834 ± 248 mm2), inner curvature (0.040 ± 0.014 mm-1 vs 0.031 ± 0.012 mm-1), and diameter (35.7 ± 2.1 mm vs 32.2 ± 4.9 mm) were not significantly different between BBG and NBBG; however, inner curvature × diameter was significantly higher in BBG (1.4 ± 0.5 vs 1.0 ± 0.3; P = .030). Inner curvature and curvature × diameter were significantly correlated with bird-beak height (R = 0.462, P = .041; R = 0.592, P = .006) and bird-beak angle (R = 0.680, P < .001; R = 0.712, P < .001). CONCLUSIONS: TEVAR bird-beak severity can be quantified and predicted with geometric modeling techniques, and the combination of high preoperative aortic inner curvature and diameter increases the risk for development of TEVAR bird-beaking.

Long-term results of hybrid repair techniques for Kommerell's diverticulum.

OBJECTIVE: The aim of this study was to evaluate early and late results of hybrid repair techniques for Kommerell's diverticulum (KD). METHODS: All patients who underwent hybrid repair (thoracic endovascular aortic repair + supra-aortic debranching) for KD between 2009 and 2018 were included in this retrospective multicenter study (three Italian centers). A proximal landing zone (PLZ) of at least 2 cm of healthy aorta was considered adequate for the deployment of a standard thoracic stent graft. The early end points were technical success, in-hospital mortality, and cerebrovascular events. Late outcomes included survival, reintervention, and patency of supra-aortic debranching. We used an embryogenetic anomaly based aortic arch classification for PLZ evaluation to identify the most appropriate hybrid adjunct. RESULTS: Sixteen patients with KD were included. According to the aforementioned classification, stent graft deployment was required in six patients (37.5%) in PLZ 0, nine patients (56.3%) in PLZ 1, and one patient (6.3%) in PLZ 2. Technical success was achieved in all patients. One patient (6.3%) died in the hospital because of posterior cerebral hemorrhage after total debranching (PLZ 0). No further cerebrovascular events were observed. One patient (6.3%) had an asymptomatic left subclavian artery-right left subclavian artery bypass occlusion and required early reintervention. The 30-day secondary patency of supra-aortic debranching was 100%. Two type II endoleaks (12.5%) were detected at 1 month through computed tomography angiography. Further transient complications were found in three cases: hemidiaphragm paralysis in one patient and recurrent laryngeal nerve paralysis in two patients. At a mean follow-up of 48 months, four patients had died because of nonaortic reasons, and one RCCA-right subclavian artery bypass had lost its patency. None of the patients reported any growth of KD after hybrid repair. Ten patients (62.5%) showed aneurysmal sac shrinkage of at least 5 mm. CONCLUSIONS: Hybrid repair is confirmed to be a safe and effective approach for KD. Operative risk is associated primarily with the invasiveness of the hybrid adjunct.

Platelets reflect the fate of type II endoleak after endovascular aneurysm repair.

OBJECTIVE: The management of type II endoleak (T2E) remains controversial because of the heterogeneous outcome. For blood-based screening to detect malignant T2E, we focused on platelets after endovascular aneurysm repair (EVAR) and compared them with the prognosis of T2Es. METHODS: From 2007 to 2015, there were 249 patients treated with EVAR for abdominal aortic aneurysm who were evaluated retrospectively. The mean follow-up period was 3.5 ± 0.2 years. T2Es that had aneurysm sac enlargement or converted to type I or type III endoleak were defined as malignant; the other T2Es were considered benign. Cases without any complications, including T2E, were defined as completed. We compared the platelet count on postoperative days (PODs) 1 to 7 with preoperative baseline values among the three groups. Sequentially, we calculated the cutoff of the platelet ratio on POD 7 to the baseline value in relation to malignant T2E using receiver operating characteristic analysis, and the cutoff ratio was 113% (sensitivity, 79%; specificity, 58%). We then reclassified T2E patients into T2E-high platelet (T2E-HP; ≥113%) or T2E-low platelet (T2E-LP; <113%) groups. The influence of platelets on T2E was evaluated with reintervention rate and cumulative aneurysm sac enlargement rate using the Kaplan-Meier method. RESULTS: T2Es were found in 70 patients (28%), and 179 patients were assigned to the completed group. Malignant and benign T2Es were found in 33 and 37 patients, respectively. No difference was found in the preoperative baseline values. On POD 7, the platelet count in the malignant T2E group was significantly lower than that in the completed and benign T2E groups (168 × 103/µL vs 207 × 103/µL and 201 × 103/µL; P = .0124). Then, 27 and 43 patients were assigned to the T2E-HP and T2E-LP groups, respectively. The reintervention-free survival rate in the T2E-LP group was lower than that in the completed group (at 3 years, 66.4% ± 8.0% vs 71.9% ± 4.0%; P = .0031). Among T2E patients, the cumulative aneurysm sac enlargement rates in the T2E-LP group were significantly higher than those in the T2E-HP group (at 3 years, 34.6% ± 8.2% vs 20.6% ± 8.2%; P = .0105). Univariate Cox proportional hazards analysis for the cumulative aneurysm sac enlargement rates among T2E patients showed that sex, dual antiplatelet therapy, and lower platelet ratio (<113%) were significant predictors; multivariate analysis showed that T2E-LP was the only significant predictor (hazard ratio, 2.60; P = .0355). CONCLUSIONS: The platelet count of patients with malignant T2Es on POD 7 was definitively lower than that of patients with completed EVAR or with benign T2Es. The lower platelet count on POD 7 could be a risk factor for aneurysm sac enlargement among patients with T2Es.