Risk factors for elective and urgent open conversion after EVAR-a retrospective observational study.

BACKGROUND: Endovascular aortic aneurysm repair (EVAR) has become the standard procedure for treating infrarenal abdominal aortic aneurysms (AAA). Various associated complications can lead to open conversion (OC). Thorough follow-up after the procedure is mandatory for the early detection of complications. Persisting perfusion of the aneurysm, a so-called endoleak (EL), paired with structural instability because of aortic wall atrophy and impaired cell functionality induced by EVAR, results in a high risk for aortic rupture. PURPOSE: The goal of this study was to detect the risk factors for elective and urgent OC as a result of EVAR-induced pathophysiological changes inside the aortic wall. RESEARCH DESIGN: Retrospective data analysis was performed on all open aortic repairs from January 2016 to December 2020. DATA COLLECTION AND ANALYSIS: Fifty patients were identified as treated by OC for failure of an infrarenal EVAR. The patients were divided into two subgroups, here depending on the urgency of surgery. Statistical analysis of patient characteristics and outcomes was performed. RESULTS: The most common indications for OC were various types of EL (74%), resulting in an aortic rupture in 15 patients. Patients with insufficient or absent follow-up were treated more frequently in an emergency setting (16% vs. 63%). The mortality rate was higher in cases of emergency OC (3% vs. 26%). CONCLUSIONS: Particularly in cases of insufficient or absent follow-up, complications such as EL pose an enormous risk for fatal aortic rupture.

Effect of Revascularization on Intramuscular Vascular Endothelial Growth Factor Levels in Peripheral Arterial Disease.

Vascular endothelial growth factor (VEGF) is a potent driver of angiogenesis, which may help to relieve ischemia in peripheral arterial disease (PAD). We aimed to investigate the role of intramuscular VEGF in ischemic and non-ischemic skeletal muscle in PAD patients before and after surgical or endovascular revascularization and different stages of PAD. Biopsies of the gastrocnemius and vastus muscles from twenty PAD patients with stenosis or occlusion of the superficial femoral artery were obtained both during revascularization and 8 weeks postoperatively. The gastrocnemius muscle was considered ischemic, while vastus muscle biopsies served as intraindividual controls. The levels of vascular endothelial growth factor in muscle lysates were then determined by ELISA. Preoperative VEGF levels were significantly higher in ischemic muscles compared to the controls (98.07 ± 61.96 pg/mL vs. 55.50 ± 27.33 pg/mL, p = 0.004). Postoperative values decreased significantly (p = 0.010) to 54.83 ± 49.60 pg/mL in gastrocnemius biopsies. No significant change was observed in vastus muscle biopsies, with mean postoperative VEGF values found at 54.16 ± 40.66 pg/mL. Since all patients still had indications for revascularization, impairment of angiogenesis mechanisms can be assumed. More research about angiogenesis in PAD is needed with the ultimate goal to improve conservative treatment.

[Aortic Complications Related to Mycobacterium bovis after Intravesical Bacille Calmette-Guérin Therapy - a Systematic Review]. / Systematische Übersichtsarbeit: aortale Komplikationen nach intravesikaler Bacillus Calmette-Guérin-Behandlung.

BACKGROUND: Aortic complications after intravesical Bacillus Calmette-Guérin (BCG) application are a rare complication of the treatment of non-muscle invasive bladder cancer. The aim of this systematic review was to perform a descriptive analysis of previously published studies and to discuss the particular challenges of diagnosis and treatment of this rare complication. MATERIAL AND METHODS: A literature search was performed in PubMed (1949-2021) and Web of Science (1900-2021) using the search terms "mycobacterium" OR "bovis" OR "BCG" AND "aorta" OR "aneurysm". In a staged review process, publications with the following inclusion criteria were included in data analysis: original paper, full-text availability in English or German and aortic complication after intravesical BCG instillation. We focused on the analysis of BCG-specific medical history data as well as treatment strategies in relation to patient outcome and the occurrence of graft infections during follow-up. RESULTS: A total of 60 individual cases were described in 55 published articles. BCG-induced mycotic aortic aneurysms can occur in all segments of the thoracoabdominal aorta, but the infrarenal aortic segment was most commonly affected (65% of cases). The most common configuration was saccular outpouchings (65%). Concomitant infections in other tissues were typical (65%). Patients with mycotic aneurysm presented with or without consecutive aortic rupture in 28% and 63%, respectively. Diagnosis was based on a combination of pathological and microbiological examinations. A common treatment algorithm was surgical infection treatment (85%) and antitubercular therapy (83%). Performed simultaneously, they resulted in a long-term survival of 81%. Graft infection after initial aortic repair with alloplastic material (n = 40) developed in ten patients (25%) during follow-up. DISCUSSION: Diagnosis of mycotic aneurysms or vascular complications after intravesical BCG application is exceptionally challenging and a high level of suspicion is required. Diagnosis is based on obtaining sample material of affected regions and the combination of patient's history, clinical presentation and pathological or microbiological examinations. Currently, no consensus guideline for optimal medical treatment options of aortic complications secondary to BCG instillation exists. The combination of surgical treatment and supportive antitubercular therapy seems to achieve the best results. Since the risk of prosthetic infection after the use of alloplastic materials remains high (25%), we strongly suggest evaluating autologous or allogenic aortic replacement during initial aortic repair.

Use of MALDI Mass Spectrometry Imaging to Identify Proteomic Signatures in Aortic Aneurysms after Endovascular Repair.

Endovascular repair (EVAR) has become the standard procedure in treating thoracic (TAA) or abdominal aortic aneurysms (AAA). Not entirely free of complications, a persisting perfusion of the aneurysm after EVAR, called Endoleak (EL), leads to reintervention and risk of secondary rupture. How the aortic wall responds to the implantation of a stentgraft and EL is mostly uncertain. We present a pilot study to identify peptide signatures and gain new insights in pathophysiological alterations of the aortic wall after EVAR using matrix-assisted laser desorption or ionization mass spectrometry imaging (MALDI-MSI). In course of or accompanying an open aortic repair, tissue sections from 15 patients (TAA = 5, AAA = 5, EVAR = 5) were collected. Regions of interest (tunica media and tunica adventitia) were defined and univariate (receiver operating characteristic analysis) statistical analysis for subgroup comparison was used. This proof-of-concept study demonstrates that MALDI-MSI is feasible to identify discriminatory peptide signatures separating TAA, AAA and EVAR. Decreased intensity distributions for actin, tropomyosin, and troponin after EVAR suggest impaired contractility in vascular smooth muscle cells. Furthermore, inability to provide energy caused by impaired respiratory chain function and continuous degradation of extracellular matrix components (collagen) might support aortic wall destabilization. In case of EL after EVAR, this mechanism may result in a weakened aortic wall with lacking ability to react on reinstating pulsatile blood flow.

Management of Tumor- and Nontumor-related Aorto-esophageal and Aorto-bronchial Fistulas.

BACKGROUND: This study aims to review and compare the clinical presentation, management, and outcome in patients with tumor-related (TR) and nontumor-related (NTR) aorto-esophageal fistula (AEF) and aorto-bronchial fistula (ABF) with particular focus on the thoracic endovascular aortic repair. METHODS: We retrospectively reviewed a series of 16 consecutive patients with TR (n = 8) and NTR (n = 8), ABF (n = 6), and AEF (n = 10) admitted to our hospital from 2011 to 2019. RESULTS: The median age was 62 years (range 46-81), with 11 men. The most common predisposing factor was esophageal or gastric cardia cancer (n = 6), followed by open repair of the thoracic aorta (n = 5). Endoluminal vacuum therapy (Endo-SPONGE®) accounted for 3 cases of AEFs. Thoracic endovascular aortic repair (TEVAR) was applied in 13 patients (4 with ABFs and 9 with AEFs). The primary technical success of the TEVARs was 100%. One patient (8%) was complicated with postoperative middle cerebral artery syndrome and left-sided hemiparesis. The respective in-hospital, 6-month, and 1-year mortality rates were 0% (n = 0), 25% (n = 2), and 25% (n = 2) for the NTR group and 63% (n = 5), 88% (n = 7), and 100% (n = 8) for the TR group. After a mean period of 13 months, 5 (31%) patients were still alive, and one patient lost to follow-up after 11 months. The survivors (n = 5) had all nontumor-related ABF. Progression of underlying cancer and hemodynamic shock were the most common causes of death. CONCLUSIONS: TEVAR represents a reliable option in the treatment of NTR ABFs. In the cases of TR fistulas and NTR AEFs, TEVAR should be applied more selectively. The associated mortality remains very high.

Graft preservation with multi-stage surgical repair of an aortoesophageal fistula after thoracic endovascular aortic repair - A case report.

INTRODUCTION: Aortoesophageal fistula (AEF) after thoracic endovascular aortic repair (TEVAR) is a rare complication associated with high mortality. Most well established treatment is multi-staged surgery, including removal of infected stent graft, esophageal resection and aortic reconstruction. PRESENTATION OF CASE: We report on a case of a 67-year-old patient with AEF and stent graft infection. Stent removal was infeasible due to the critical condition of the patient and history of multiple vascular procedures of the thoracoabdominal aorta. Surgical management included staged right and left thoracotomy, esophagectomy, vacuum therapy (VAC) on stent prosthesis and subsequent graft coverage with omental and pleural flaps, followed by esophageal reconstruction. DISCUSSION: An established and generally accepted treatment approach for graft infections does not exist. Graft explantation and radical surgical debridement is the therapy of choice for prosthetic infections. In comparison to previous literature, our case represents the complexity of the treatment of AEF and its enormous demands on the interdisciplinary medical team. CONCLUSION: Our report shows that in an emergency situation without other surgical options as in our case, it was possible to stabilize the patient through application of vacuum therapy in the infected area, with simultaneous esophagectomy, followed by secondary staged reconstruction with omentoplasty and pleura parietalis flap remaining the graft in situ.