Management of the False Lumen in Post Type A Aortic Dissection Arch Aneurysms Treated With Branched Endografts

INTRODUCTION

The treatment of chronic postdissection aneurysms of the aortic arch is a challenge. This study aims to describe false lumen management after aortic arch endovascular repair of post-type A dissection aneurysms treated with a branched endograft.

METHODS

In this single-center retrospective observational study, all consecutive patients undergoing endovascular treatment of aneurysmal degeneration of chronic type A aortic dissections following open repair were enrolled. The primary endpoint was maximal aortic diameter evolution measured on computed tomography angiography (CTA) performed during follow-up. Secondary endpoints included procedural success, aortic re intervention, and remodeling during follow-up.

RESULTS

Between January 2017 and June 2020, 22 patients underwent endovascular branched arch repair for post type A dissection aneurysms. Technical success was 100%. Thirteen patients (59%) had dissection involvement of at least 1 supra-aortic vessel. Midterm follow-up CTA was performed for 20 patients, 23.1 (±13.3) months after the procedure. Maximal aortic diameter at the level of the repair was decreasing in 13 (65%) patients, increasing in 2 (10%) patients, and no change was observed in 5 (25%) patients. During follow-up, 7 patients (35%) required aortic reintervention. Thoracic candy plugs were implanted for distal false lumen occlusion in 15 patients and associated with a high rate of complete remodeling (6/15 patients, 40%).

CONCLUSION

Arch branch endografting of aneurysmal evolution of a post type A dissection aortic arch is a safe and feasible option in experienced hands. Candy plug use in favorable anatomies seems to be associated with accelerated remodeling of the aorta.

CLINICAL IMPACT

There are currently no recommendations on dissected supra- aortic vessels management and the use of thoracic aorta false lumen occlusion devices during endovascular repair of chronic post dissection aneurysm of the aortic arch with branched endografts. Based on our clinical experience reported in the current manuscript, we propose a treatment algorithm for the management of the false lumen in this setting.

Iliac branch device to treat type IB endoleak with a brachial access or an "up-and-over" transfemoral technique

PURPOSE

This study aimed to review the results of secondary IBD (iliac branch device) implantation in patients with type IB endoleak after prior fenestrated and/or branched or infrarenal endovascular aortic repair (F/B-EVAR or EVAR), using either brachial access or an "up-and-over" transfemoral technique.

METHODS

A retrospective single centre analysis was conducted between Jan 2016 and Oct 2021 including consecutive patients that underwent IBD to correct a type IB endoleak after prior EVAR or F/B-EVAR. Groups were defined by arterial access which was either brachial (group 1) or transfemoral (group 2). All IBD implanted were manufactured by Cook Medical (INC, Bloomington, IN, USA). Demographics, anatomical features, technical success, and 30-day major adverse events (MAE) were recorded according to the current SVS standards. Survival curves according to Kaplan-Meier were calculated. Branch instability was a composite endpoint of any IIA branch-related complication or reintervention indicated to treat endoleak, kink, disconnection, stenosis, occlusion or rupture.

RESULTS

Overall, 28 patients (93% male, median age 74 years) receiving 32 IBDs were included, with 14 patients in each group. Prior endovascular aortic repairs were 23 EVAR and 5 F/B-EVAR, with time from initial repair being 58 months [48, 70]. Median pre-IBD maximal aneurysm diameter was 63.5 mm [59.0, 78.0]. Patients' baseline characteristics were similar in both groups except for pulmonary status. All procedures were performed in a hybrid operative room. Median total operating time, fluoroscopy time and dose area product were 120 min [86, 167], 23 min [15, 32] and 54 Gy.cm2 [40, 62], respectively. Total operating time was shorter in group 2 (p=0.006). Technical success rate was 100% and no early death reported. One 30-day MAE occurred including a medically treated colonic ischemia (group 2). Aortic-related secondary interventions were required in 7 patients (5 in group 1 and 2 in group 2) including 3 surgical explantations. Median follow-up was 31 months [24, 42] and 6 months [3, 10] in group 1 and 2, respectively. In group 1, 2-year freedom from aortic-related secondary intervention and IIA branch instability were 84.6% [67.1-100] and 92.3% [78.9-100], respectively. In group 2, 6-month freedom from aortic-related secondary intervention and IIA branch instability were 87.5% [67.3-100] and 91.7% [77.3-100], respectively.

CONCLUSION

The secondary implantation of IBD to correct distal type I endoleak of previous aortic stent-graft is safe with a high technical success rate. The "up-and-over" technique could be considered as an alternative to the brachial access in patients with suitable anatomy.

Case series of aortic arch disease treated with branched stent-grafts

Background

Surgical repair of aortic arch pathology is complex and associated with significant morbidity and mortality. Alternative approaches have been developed to reduce these risks, including the use of thoracic stent-grafts with fenestrations or in combination with bypass procedures to maintain supra-aortic trunk blood flow. Branched stent-grafts are a novel approach to treat aortic arch pathology.

Methods

Consecutive patients with aortic arch disease presenting to a single university hospital vascular centre were considered for branched stent-graft repair (October 2010 to January 2017). Patients were assessed in a multidisciplinary setting including a cardiologist, cardiac surgeon and vascular surgeon. All patients were considered prohibitively high risk for standard open surgical repair. The study used reporting standards for endovascular aortic repair and PROCESS (Preferred Reporting of Case Series in Surgery) guidelines.

Results

Some 30 patients (25 men) underwent attempted branch stent-graft repair. Mean age was 68 (range 37–84) years. Eighteen patients had chronic aortic dissection, 11 patients had an aneurysm and one had a penetrating ulcer. Fourteen patients had disease in aortic arch zone 0, six in zone 1 and ten in zone 2. Twenty-five patients had undergone previous aortic surgery and 24 required surgical revascularization of the left subclavian artery. Technical success was achieved in 27 of 30 patients. Four patients had an endoleak (type Ia, 1; type II, 3). The in-hospital mortality rate was three of 30. Mean length of follow-up was 12·0 (range 1·0–67·8) months, during which time 12 patients required an aortic-related reintervention.

Conclusion

Repair of aortic arch pathology using branched stent-grafting appears feasible. Before widespread adoption of this technology, further studies are required to standardize the technique and identify which patients are most likely to benefit.

Evaluation of a new imaging software for aortic endograft planning

OBJECTIVE

The aim of this study was to evaluate a new 3D Workstation workflow (EVAR Assist, Advantage Windows, GE Healthcare, Chalfont, UK) (EA-AW) designed to simplify complex EVAR planning.

PATIENTS AND METHODS

All pre-operative computed tomography (CT) scans of patients who underwent repair at our institution of a complex aortic aneurysm using fenestrated endovascular repair (f-EVAR) between January and September 2014, were reviewed. For each patient, imaging analysis (12 measures: aortic diameters and length and "clock position" of visceral artery) was performed on two different workstations: Aquarius (TeraRecon, San Mateo, CA, USA) and EA-AW. According to a standardized protocol, three endovascular surgeons experienced in aortic endograft planning, performed image analyses and data collection independently. We analyzed an internal assessment between observers (on the Aquarius 3DWS) and an external assessment comparing these results with the planning center (PC) data used to custom the fenestrated endograft of the patients enrolled in this study. Finally, we compared both 3DWS data to determine the accuracy and the reproducibility. A p-value < .05 was considered as statistically significant. Complete agreement between operators was defined as 1.0.

RESULTS

Intra- and inter-observer variability (interclass correlation coefficients - ICC: 0.81-.091) was very low and confirmed the reliability of our planners. The ICC comparison between EA-AW and Aquarius was excellent (> 0.8 for both), thus confirming the reproducibility and reliability of the new EA-AW application. Aortic and iliac necks diameters and lengths were similarly reported with both workstations. In our study, the mean difference in distance and orientation evaluation of target vessels evaluated by the two workstations was marginal and has no impact on clinical practice in term of device manufacturing.

CONCLUSIONS

We showed that complex EVAR planning can be performed with this new dedicated 3D workstation workflow with a good reproducibility.

Editor's Choice - Comparison of Renal Outcomes in Patients Treated by Zenith® Fenestrated and Zenith® Abdominal Aortic Aneurysm Stent grafts in US Prospective Pivotal Trials

OBJECTIVE/BACKGROUND

Fenestrated endovascular repair (FEVAR) has been used to treat complex abdominal aortic aneurysms (AAAs). The risk of renal function deterioration compared with infrarenal endovascular aortic repair (EVAR) has not been determined.

METHODS

Patients with preserved renal function (estimated glomerular filtration rate [eGFR] > 45 mL/minute) enrolled in two prospective, non-randomised studies evaluating Zenith fenestrated and AAA stent grafts were matched (1:2) by propensity scores for age, sex, hypertension, diabetes, and pre-operative eGFR. Sixty-seven patients were treated by FEVAR and 134 matched controls treated by EVAR. Mean follow-up was 30 ± 20 months. Outcomes included acute kidney injury (AKI) defined by RIFLE and changes in serum creatinine (sCr), eGFR, and chronic kidney disease (CKD) staging up to 5 years.

RESULTS

AKI at 1 month was similar between groups, with > 25% decline in eGFR observed in 5% of FEVAR and 9% of EVAR patients (p = .39). There were no significant differences in > 25% decline in eGFR at 2 years (FEVAR 20% vs. EVAR 20%; p > .99) or 5 years (FEVAR 27% vs. EVAR 50%; p = .50). Progression to stage IV-V CKD was similar at 2 years (FEVAR 2% vs. EVAR 3%; p > .99) and 5 years (FEVAR 7% vs. EVAR 8%; p > .99), with similar sCr and eGFR up to 5 years. During follow-up, there were more renal artery stenosis/occlusions (15/67 [22%] vs. 3/134 [2%]; p < .001) and renal related re-interventions (12/67 [18%] vs. 4/134 [3%]; p < .001) in patients treated by FEVAR. Rate of progression to renal failure requiring dialysis was low and identical in both groups (1.5% vs. 1.5%; p > .99).

CONCLUSION

Aortic repair with FEVAR and EVAR was associated with similar rates of renal function deterioration in patients with preserved pre-operative renal function. Renal related re-interventions were higher following FEVAR, although net changes in renal function were similar in both groups.

Early Experience of Endovascular Repair of Post-dissection Aneurysms Involving the Thoraco-abdominal Aorta and the Arch

OBJECTIVES

Outcomes are reported in management of post-dissection aneurysms involving the aortic arch and/or thoraco-abdominal segment (TAAA) treated with fenestrated and branched (complex) endografts.

METHODS

This report includes all patients with chronic post-dissection aneurysms >55 mm in diameter, deemed unfit for open surgery, treated using complex endografts between October 2011 and March 2015. When appropriate, staged management strategies including left subclavian artery revascularization, thoracic endografting, dissection flap fenestration or tear enlargement, and other endovascular procedures were performed at least 3 weeks prior to definitive complex endovascular repair. The following outcome data were collected prospectively at discharge, 12 months and annually thereafter: technical success, endoleaks, target vessel patency, false lumen patency, aneurysm diameter, major and minor complications, re-interventions, and mortality.

RESULTS

The cohort comprised 23 patients with a median age of 65 years. Staged procedures were performed in 14 patients (61%). Seven patients with dissections involving the arch were treated with inner branched endografts, and 16 TAAA patients were treated with fenestrated or branched endografts. The technical success rate was 71% following arch repair and 100% following TAAA repair. During early follow up, one of the arch group patients died and one in the TAAA group suffered spinal cord ischemia. The median follow up was 12 months (range 3-48), during which time one patient died of causes unrelated to aneurysm or treatment. Two early re-interventions were performed in the arch group to correct access vessel complications and there were a further two late re-interventions in the TAAA group to treat endoleaks. All target vessels (n = 72) remained patent.

CONCLUSIONS

This experience indicates that complex endovascular repair of post-dissection aneurysms is a viable alternative to open repair in patients deemed unfit for open surgery. There are insufficient data to allow comparison with the outcome of open surgery in anatomically similar, but fit, patients.

The neuron-derived orphan receptor 1 (NOR1) is induced upon human alternative macrophage polarization and stimulates the expression of markers of the M2 phenotype

BACKGROUND

Atherosclerosis is an inflammatory disease in which macrophages play a crucial role. Macrophages are present in different phenotypes, with at the extremes of the spectrum the classical M1 pro-inflammatory and the alternative M2 anti-inflammatory macrophages. The neuron-derived orphan receptor 1 (NOR1), together with Nur77 and Nurr1, are members of the NR4A orphan nuclear receptor family, expressed in human atherosclerotic lesion macrophages. However, the role of NOR1 in human macrophages has not been studied yet.

OBJECTIVES

To determine the expression and the functions of NOR1 in human alternative macrophages.

METHODS AND RESULTS

In vitro IL-4 polarization of primary monocytes into alternative M2 macrophages enhances NOR1 expression in human but not in mouse macrophages. Moreover, NOR1 expression is most abundant in CD68+MR+ alternative macrophage-enriched areas of human atherosclerotic plaques in vivo. Silencing NOR1 in human alternative macrophages decreases the expression of several M2 markers such as the Mannose Receptor (MR), Interleukin-1 Receptor antagonist (IL-1Ra), CD200 Receptor (CD200R), coagulation factor XIII A1 polypeptide (F13A1), Interleukin 10 (IL-10) and the Peroxisome Proliferator-Activated Receptor (PPAR)γ. Bioinformatical analysis identified F13A1, IL-1Ra, IL-10 and the Matrix Metalloproteinase-9 (MMP9) as potential target genes of NOR1 in human alternative macrophages. Moreover, expression and enzymatic activity of MMP9 are induced by silencing and repressed by NOR1 overexpression in M2 macrophages.

CONCLUSIONS

These data identify NOR1 as a transcription factor induced during alternative differentiation of human macrophages and demonstrate that NOR1 modifies the alternative macrophage phenotype.

Current and future perspectives in the repair of aneurysms involving the aortic arch

The repair of aneurysms involving the aortic arch is technically and physiologically demanding. Historically, these aneurysms have been treated using open surgical techniques that require cardiopulmonary bypass and deep hypothermic circulatory arrest. Many patients have been deemed "untreatable" and among those selected for surgery there are reported risks of death in 2% to 16.5% and stroke rates ranging from 2% to 18%. "Hybrid arch repair" combines one of a number of open surgical procedures (to secure a proximal landing zone for an endograft) with subsequent or immediate placement of an endograft in the arch and descending aorta. Although this concept is described as "minimally invasive" because it avoids aortic cross-clamping and hypothermic circulatory arrest, the morbidity and mortality rates remain considerable (mortality 0% to 15%, stroke 0% to 11%). Ongoing development of endograft technology has enabled total endovascular repair of complex aortic aneurysms involving the visceral segment, using fenestrated and branched endografts. Encouraging early results in this anatomy have inspired extension of the concept to include the aortic arch and great vessels. These strategies can be considered in patients generally at high-risk for the conventional procedures. However, the endeavour is at an early stage of its development and the arch poses unique challenges including the potential for stroke, angulation of the arch and the great vessel ostia to the arch, extremely high volume flow, three-dimensional pulsation and rotation with the cardiac cycle and the proximity of the aortic valve and coronary arteries.

The coronary artery disease-associated gene C6ORF105 is expressed in human macrophages under the transcriptional control of PPARγ

Coronary artery disease (CAD) is a major cause of morbidity and mortality. Mutations in C6ORF105, associated with decreased gene expression, positively correlate with the risk of CAD in Chinese populations. Moreover, the C6ORF105-encoded protein may play a role in coagulation. Here, we report that C6ORF105 gene expression is lower in circulating mononuclear cells from obese diabetic than lean subjects. Moreover, C6ORF105 is expressed in human macrophages and atherosclerotic lesions, where its expression positively correlates with expression of the transcription factor Peroxisome Proliferator-Activated Receptor (PPAR)γ. Activation of PPARγ increases, in a PPARγ-dependent manner, the expression of C6ORF105 in human macrophages and atherosclerotic lesions.

Juxtarenal aortic aneurysm with hostile neck anatomy: midterm results of minilaparotomy versus f-EVAR

AIM

The aim of this study was to compare the results of complex aneurysm (hostile neck anatomies) repair in high-risk patients with two minimally invasive techniques, fenestrated endografting (f-EVAR where EVAR stands for endovascular aneurysm repair) and minilaparotomy.

METHODS

All high-risk patients (N.=50, group 1) with hostile neck abdominal aortic aneurysms (AAAs) operated in the vascular surgery department of the "Policlinico Universitario G. Martino" of Messina (Italy) during a 5-year period (January 2006-December 2010) were cross-matched with 50 similar patients (group 2) treated in the Vascular Surgery Department of the "Hopital Cardiologique" University of Lille (France) with similar anatomies, comorbidities and risk factors. The patients in group 1 underwent open minilaparotomy surgery, and the patients in group 2 were treated with f-EVAR. The aim of our study was to compare perioperative complications, survival and reintervention rates.

RESULTS

Perioperative cardiac complications occurred in 5 patients (10%) in group 1, and 1 patient (2%) in group 2 (P<0.092). Renal impairment not requiring permanent hemodialysis was significantly higher in group 1 (14% vs. 2% P<0.027), as well as respiratory complications (32% vs. 2% P<0.0001). Five patients (10%) in group 1 underwent reintervention vs. 4 patients in group 2 (P<0.7268). There was no statistically significant difference for survival rates at 30 days (92% in group 1 and 96% in group 2; P=0.399); at six months (90% vs. 96%; P=0.239); at one year (90% vs. 96%; P=0.239); and at two years (84% vs. 94%; P=0.110). However, we observed statistically significant differences in survival rates at three years (74% vs. 94%; P<0.006); at four years (70% vs. 86%; P<0.005); and at five years (65% vs. 68%; P<0.003).

CONCLUSION

Our results showed that both techniques are effective in the treatment of AAA with hostile neck in high-risk patients. Although operative mortality rate was not statistically different, f-EVAR showed better results in terms of early complications and late survival.

Chronic dissection - indications for treatment with branched and fenestrated stent-grafts

The treatment of chronic aortic dissection is a major challenge for the vascular surgeon. Close imaging follow-up after the acute episode frequently identifies dilation of untreated aortic segments. Aortic dissection often extends to both the supra-aortic trunks and to the visceral aorta. The poor medical condition that often characterizes these patients may preclude extensive open surgical repair. Recent advances in endovascular techniques provide a valid alternative to open surgery. These complex lesions can now be managed using thoracic branched and fenestrated endografts. However, clinical data are scarce and only 3 small series from 3 high-volume aortic centers are currently available. Careful anatomical study on 3D workstations is mandatory to select patients that are candidates for complex endovascular exclusion; a specific focus on the available working space within the true lumen, extension to the arch and/or the visceral/renal arteries, and false lumen perfusion of visceral vessels is required. An excellent understanding of those anatomic details demands high-quality preoperative CTA. Intraoperative advanced imaging applications are a major adjunct in the achievement of technical success.

A new score to predict post operative complications after endovascular treatment of thoraco abdominal aortic aneurysms

BACKGROUND

The endovascular treatment of thoraco abdominal aortic aneurysms (TAAA) is a minimally invasive solution. However, patient selection remains a major problem. We have analysed our experience to identify the risk factors for post-operative morbidity and mortality and to construct a scoring system to identify those patients likely to benefit from this treatment.

METHODS

We have analysed a consecutive cohort of patients treated electively for TAAA using endovascular techniques between 2006 and October 2012. All data were collected prospectively. The risk factors associated with spinal cord ischemia (SCI), the need for post-operative dialysis and 30 day mortality were determined using multivariate statistical techniques and a logistic regression model including all variables that were significant on univariate analysis (p < 0.05). A predictive score was calculated using a Received Operating Characteristic (ROC) curve, defining best specificity and sensibility.

RESULTS

We analysed the data from 123 patients (median age 70 years). The 30 day mortality rate was 8% (10 patients). The SCI rate was 6% (7 patients). One patient (1%) required long-term dialysis after the aortic procedure. The cumulative early mortality, SCI and permanent dialysis rate was 14% (17 patients). In multivariate analysis, adverse outcome was associated with advanced age (OR = 1.110 ; p = 0.022), and Crawford type I or II or III (OR = 9.292 ; p = 0.002) as compared with Crawford type IV. Pre-operative beta blocker (BB) treatment was a protective factor (OR = 0.099 ; p = 0.005). A predictive score was then constructed : Score = -10.060 + 0.104x(A) +2.229x(B) -2.315x(C) (A = patient age ; B = 1 if TAAA Crawford type 1, 2 or 3, 0 if TAAA type 4 ; C = 1 if on-going BB treatment (30 days pre-surgery minimum), 0 if none). Its sensitivity and specificity were 88% and 89% respectively.

CONCLUSIONS

We propose a simple predictive scoring system. This tool is useful in predicting the most feared complications after endovascular TAAA repair and has potential use in the identification and counselling of vulnerable patients being considered for surgery. More data are needed to refine the prediction of individual operative risks.

Techniques to reduce radiation and contrast volume during EVAR

There is a large variability observed in the literature regarding radiation exposure and contrast volume injection during endovascular aortic repair (EVAR). Reducing both in order to decrease their respective toxicities must be a priority for the endovascular therapist. Radiation dose reduction requires a strict application of the "as low as reasonably achievable" principles. Firstly, all X-ray system settings should be defaulted to low dose, and fluoroscopic time reduced as much as possible. Digital subtraction angiography runs should be replaced by recorded fluoroscopy runs when possible. Magnification should be avoided, whereas collimation should be systematic to minimize scatter radiation and focus only on the area of interest. Advanced imaging modes can also contribute to dose reduction. For instance, image fusion can facilitate endovascular navigation, and allow table and C-arm positioning without fluoroscopy. In our experience, routine use of image fusion during EVAR significantly reduces both radiation exposure and contrast volumes during complex EVAR. To make these imaging modes useable in real life settings, the X-ray system should be fully controlled by the operator from table side. Reducing iodinated contrast volume, while maintaining image quality, can also be achieved through the use of automated contrast injectors. Additionally, alternative contrast agents, like carbon dioxide (CO2) and gadolinium, have also been evaluated and can be used in specific cases. Contrast-enhanced ultrasound and intravascular ultrasonography are currently developed as potential alternatives to both iodinated contrast use and X-ray during EVAR. Lastly, specific education and training of operators in radiation protection are essential.

Editor's choice--hybrid treatment of thoracic, thoracoabdominal, and abdominal aortic aneurysms: a multicenter retrospective study

OBJECTIVES

The aim of this study was to assess the results of hybrid techniques for the treatment of thoracic, thoracoabdominal, and abdominal aortic aneurysms based on multicenter results and the various series regarding hybrid procedures reported in the literature.

METHODS

The results of 76 hybrid procedures performed in 19 French university hospital centers between November 2001 and October 2011 were collected. There were 50 men and 26 women, mean age 68.2 (35-86) years. All patients were considered at high risk (ASA≥3) for conventional surgery. Aneurysms involved the thoracic, abdominal, and thoracoabdominal aorta in five, 14, and 57 cases respectively. There were 11 emergent repairs. The revascularization of four visceral arteries was performed in 38 cases. Between one and three visceral arteries were revascularized in the other cases. Visceral artery debranching and stent graft deployment were performed in a one-stage procedure in 53 cases and in a two-stage procedure in 23 cases.

RESULTS

There were 26 (34.2%) postoperative deaths. Nine of the survivors developed paraplegia, of which one resolved completely. Bowel ischemia occurred in 13 cases (17.1%), and one patient was treated by a superior mesenteric artery bypass. Four patients required long-term hemodialysis. Postoperative computed tomography scan showed a type II endoleak in two patients.

CONCLUSIONS

Morbidity and mortality in this study were greater than previously reported. Candidates for hybrid aortic repair should be carefully selected.