Relevance of Type II Endoleak After Endovascular Repair of Ruptured Abdominal Aortic Aneurysms: A Retrospective Single-Center Cohort Study.

INTRODUCTION: Endovascular aortic repair (EVAR) is widely used as an alternative to open repair in elective and even in emergent cases of ruptured abdominal aortic aneurysm (rAAA). One of the most frequent complications after EVAR is type II endoleak (T2EL). In elective therapy, evidence-based therapeutic recommendations for T2EL are limited. Completely unclear is the role of T2EL after EVAR for rAAA (rEVAR). This study aims to investigate the significance of T2ELs after rEVAR. PATIENTS AND METHODS: This is a retrospective single-center data analysis of all patients who underwent rEVAR between January 2010 and December 2020 with primary T2EL. The outcome criteria were overall and T2EL-related mortality and reintervention rate as well as development of aneurysm diameter over follow-up (FU). RESULTS: During the study period between January 2010 and December 2020, 35 (25%) out of 138 patients with rEVAR presented a primary postoperative T2EL (age 74±11 years, 34 males). At rupture, mean aneurysm diameter was 73±12 mm. Follow-up was 26 (0-172) months. The reintervention-free survival was 69% (95% confidence interval [CI]: 55%-86%) at 30 days, 58% (95% CI: 43%-78%) at 1 year, and 52% (95% CI: 36%-75%) at 3 years. In 40% (n=14), T2ELs resolved spontaneously within a median time of 3.4 (0.03-85.6) months. The overall and T2EL reintervention rates were 43% (n=15) and 9% (n=3), respectively. Within 30 days, 11 patients (31%) required reintervention, of which 2 were T2EL related. Aneurysm sac growth by ≥5 mm was seen in 3 patients (9%), and aneurysm shrinkage rate was significantly higher in sealed T2EL group (86% vs 5%, p<0.0001). The overall survival was 85% (95% CI: 74%-98%) at 30 days, 75% (95% CI: 61%-92%) at 1 year, and 67% (95% CI: 51%-87%) at 3 years. Six deaths were aneurysm related, while 1 was T2EL related within the first 30 days due to persistent hemorrhage. During FU, one more patient died due to a T2EL-related secondary rupture (T2EL-related mortality, 5.7%, n=2). Multivariable analysis revealed that arterial hypertension was associated with an increased risk for reintervention (hazard ratio [HR]: 27.8, 95% CI: 1.48-521, p=0.026) and age was associated with an increased risk for mortality (HR 1.14, 95% CI: 1.04-1.26, p=0.005). CONCLUSION: T2ELs after rEVAR showed a benign course in most cases. In the short term, the possibility of persistent bleeding should be considered. In the mid term, a consequent FU protocol is required to detect known late complications after EVAR at an early stage and to prevent secondary rupture and death.

Inter-Hospital Transfer of Patients With Ruptured Abdominal Aortic Aneurysm in Switzerland.

OBJECTIVE: To analyse the association between inter-hospital transfer and hospital mortality in patients with ruptured abdominal aortic aneurysms (rAAA) in Switzerland. METHODS: Secondary data analysis of case related hospital discharge data from the Swiss Federal Statistical Office for the years 2009 - 2018. All cases with rAAA as primary or secondary diagnosis were included. Cases with rAAA as a secondary diagnosis without surgical treatment and cases that had been transferred to another hospital without surgical treatment at the referring hospital were excluded. Logistic regression models for hospital mortality were constructed with age, sex, type of admission, van Walraven comorbidity score, type of treatment, insurance class, hospital level, and year of treatment as independent variables. RESULTS: A total of 1 798 cases with rAAA were treated either surgically (62.5%) or palliatively (37.5%) in Switzerland from 1 January 2009 to 31 December 2018. Of these cases, 72.9% were treated directly (surgically or palliatively) at the hospital of first presentation, whereas 27.1% of all cases with rAAA were transferred between hospitals. The overall crude hospital mortality was 50.3%; being 23.1% in the surgically treated cohort and 95.7% in the palliatively treated cohort. Inter-hospital transfer was associated with better survival compared with patients who were admitted directly (OR 0.52; 95% CI 0.36 - 0.75; p < .001). Treatment in major hospitals was associated with significantly higher mortality rate compared with university hospitals (OR 1.98; 1.41 - 2.79; p < .001). There was no evidence of an association between open repair and hospital mortality (OR 1.06; 0.77 - 1.48; p = .72) compared with endovascular repair. CONCLUSION: In a healthcare system such as Switzerland's with a highly specialised rescue chain, transfer of haemodynamically stable patients with rAAA is probably safe. In this setting, centralised medical care might outweigh the potential disadvantages of a short delay due to patient transfer. Further studies are needed to address potential confounding factors such as haemodynamic and anatomical features.

Acute abdominal aortic occlusion: A 16-year single-center experience.

BACKGROUND: Acute abdominal aortic occlusion (AAO) is a rare vascular emergency associated with high morbidity and mortality. In the present study, we analyzed the clinical management and outcomes for a consecutive patient series during a 16-year period. METHODS: We included all patients with an acute AAO and bilateral acute limb ischemia who had been treated between 2004 and 2019. Patients with dissection, aneurysm rupture, or chronic occlusive disease were excluded. The patient characteristics, surgical procedures, and outcomes were extracted retrospectively from a prospective aortic database, electronic patient files, and outpatient examination records. The extent of ischemia was classified according to the TASC II (Inter-Society Consensus for the Management of Peripheral Arterial Disease) section on acute limb ischemia. The primary endpoints were 30-day mortality (safety endpoint) and the combined 6-month amputation and/or death rate (efficacy endpoint). The follow-up outcomes, amputation rates, and 30-day complications were evaluated as secondary endpoints. The patient cohort was divided into four 4-year groups (2004-2007, 2008-2011, 2012-2015, 2016-2019) to assess the outcome changes over time. Statistical analysis included χ2 tests and univariate and linear regression analyses. RESULTS: A total of 74 patients (57% male; median age, 64.5 years) with an acute AAO were identified. Arterial thrombosis was the most common etiology (66%). The extent of ischemia was TASC I, IIa, IIb, and III in 7%, 39%, 40%, and 14%, respectively. The patient numbers had increased significantly over time (P = .016). Of the patients, 42% had undergone open transfemoral recanalization (including hybrid procedures), 35% open aortic surgery, 15% extra-anatomic bypass surgery, and 5% (four patients) endovascular therapy alone. The overall 30-day mortality rate was 23%, and the 6-month amputation and/or death rate was 43%. The 30-day mortality rate had declined significantly from 54% for 2004 to 2007 to 10% for 2011 to 2015 (odds ratio [OR], 0.10; 95% confidence interval [CI], 0.001-0.52) and 20% for 2016 to 2019 (OR, 0.21; 95% CI, 0.05-0.90), a statistically nonsignificant trend showing that the relative decline in the use of open aortic procedures was associated with decreased 30-day mortality (P = .06). Univariate analysis indicated that elevated serum lactate on admission (OR, 3.33; 95% CI, 1.06-10.48) and an advanced stage of limb ischemia (OR, 4.33), were strongly associated with an increased 30-day mortality rate. The incidence of severe postoperative systemic complications also indicated a greater incidence of both primary endpoints. The 6-month amputation and/or mortality rates were also affected by the presence of atrial fibrillation (OR, 3.63; 95% CI, 1.34-9.79) and increased patient age (OR, 3.96; 95% CI, 1.49-10.53). CONCLUSIONS: Acute AAO remains a life-threatening emergency. Immediate transfemoral open or endovascular techniques should be preferred, if technically possible and proper intraoperative imaging is available.

Influence of Bridging Stent Graft Implantation into the Renal Artery during Complex Endovascular Aortic Procedures on the Renal Resistance Index.

Comparative sonographic examination of the renal resistance index (RRI) can provide evidence of renal artery stenosis. The extent to which the RRI is changed after stent graft implantation is not known. The aim of this study was to investigate the influence of stent graft implantation into non-diseased renal arteries during endovascular treatment of pararenal aortic aneurysms on the RRI. Sonographic examinations of the kidneys were conducted using a GE ultrasound system. The evaluation was performed according to the European Society for Vascular Surgery (ESVS) 2D standard criteria. RRI values were determined in consecutive patients on the day before and after stent graft implantation and compared for each kidney. A total of 32 consecutive patients (73.9 ± 8.2 years, 5 females, 27 males) were treated with a fenestrated or branched aortic stent graft including bridging stent graft implantations into both renal arteries and received pre- and postinterventional examinations. Sonomorphologically, the examined kidneys were inconspicuous. The arborisation of the renal perfusion was preserved pre- and post-implantation. The RRI did not differ (0.66 ± 0.06 versus 0.67 ± 0.07; p = ns). Successful stent graft implantation into non-stenosed renal arteries did not lead to a relevant change in RRI. Therefore, the RRI is a suitable tool for assessing renal perfusion after fenestrated or branched endovascular aortic therapy.

Hospital Incidence, Sex Disparities, and Perioperative Mortality in Open Surgically Treated Patients with Aneurysms of the Ascending Aorta and Aortic Arch in Switzerland.

OBJECTIVE: To analyze the epidemiological shifts in the incidence of ascending and arch aortic aneurysms (AA) treated with open surgery in the context of evolving endovascular options on a national basis. METHODS: Between 1 January 2009 and 31 December 2018, 4388 cases were admitted to the hospital with either ruptured (r)AA or non-ruptured (nr)AA as the primary or secondary diagnosis. Patients were classified as having AA based on inclusion and exclusion criteria. RESULTS: The age-standardized hospital incidence rates for treatment of nrAA were 7.8 (95% confidence interval (CI): 6.9 to 8.7) in 100,000 men and 2.9 (2.4 to 3.4) in 100,000 women and were stable over time. The overall raw in-hospital mortality rate was 2.0% and was significantly lower in males compared to women (1.6% vs. 2.8%, p = 0.015). Higher van Walraven scores (OR: 1.08 per point; 95%CI: 1.06 to 1.11; p = 0.001) and higher age (OR 1.05 per year; (95%CI: 1.02 to 1.07, p = 0.045) were significantly associated with hospital mortality. CONCLUSIONS: Endovascular surgery seems to have no influence on hospital incidence in patients treated with conventional surgery for AA in Switzerland. There was a significant reduction in in-hospital mortality in both men and women, with age and the von Walraven score being independent factors for worse outcomes.

Bypass Patency and Amputation-Free Survival after Popliteal Aneurysm Exclusion Significantly Depends on Patient Age and Medical Complications: A Detailed Dual-Center Analysis of 395 Consecutive Elective and Emergency Procedures.

Background/Objectives: A popliteal artery aneurysm (PAA) is traditionally treated by an open PAA repair (OPAR) with a popliteo-popliteal venous graft interposition. Although excellent outcomes have been reported in elective cases, the results are much worse in cases of emergency presentation or with the necessity of adjunct procedures. This study aimed to identify the risk factors that might decrease amputation-free survival (efficacy endpoint) and lower graft patency (technical endpoint). Patients and Methods: A dual-center retrospective analysis was performed from 2000 to 2021 covering all consecutive PAA repairs stratified for elective vs. emergency repair, considering the patient (i.e., age and comorbidities), PAA (i.e., diameter and tibial runoff vessels), and procedural characteristics (i.e., procedure time, material, and bypass configuration). Descriptive, univariate, and multivariate statistics were used. Results: In 316 patients (69.8 ± 10.5 years), 395 PAAs (mean diameter 31.9 ± 12.9 mm) were operated, 67 as an emergency procedure (6× rupture; 93.8% severe acute limb ischemia). The majority had OPAR (366 procedures). Emergency patients had worse pre- and postoperative tibial runoff, longer procedure times, and more complex reconstructions harboring a variety of adjunct procedures as well as more medical and surgical complications (all p < 0.001). Overall, the in-hospital major amputation rate and mortality rate were 3.6% and 0.8%, respectively. The median follow-up was 49 months. Five-year primary and secondary patency rates were 80% and 94.7%. Patency for venous grafts outperformed alloplastic and composite reconstructions (p < 0.001), but prolonged the average procedure time by 51.4 (24.3-78.6) min (p < 0.001). Amputation-free survival was significantly better after elective procedures (p < 0.001), but only during the early (in-hospital) phase. An increase in patient age and any medical complications were significant negative predictors, regardless of the aneurysm size. Conclusions: A popliteo-popliteal vein interposition remains the gold standard for treatment despite a probably longer procedure time for both elective and emergency PAA repairs. To determine the most effective treatment strategies for older and probably frailer patients, factors such as the aneurysm size and the patient's overall condition should be considered.

Hospital Incidence, Treatment, and Outcome of 885 Patients with Thoracoabdominal Aortic Aneurysms Treated in Switzerland over 10 Years-A Secondary Analysis of Swiss DRG Data.

Despite the development of fenestrated and branched endovascular aortic repair (f/bEVAR), the surgical management of thoraco-abdominal aortic aneurysms (TAAAs) remains a major challenge. The aim of this study was to analyse the hospital incidence and hospital mortality of patients treated for TAAAs in Switzerland. Secondary data analysis was performed using nationwide administrative discharge data from 2009-2018. Standardised incidence rates and adjusted mortality rates were calculated. A total of 885 cases were identified (83.2% nonruptured (nrTAAA), 16.8% ruptured (rTAAA)), where 69.3% were male. The hospital incidence rate for nrTAAA was 0.4 per 100,000 women and 0.9 per 100,000 men in 2009, which had doubled for both sexes by 2018. For rTAAA, there was no trend over the years. The most common procedure was f/bEVAR (44.2%), followed by OAR (39.5%), and 9.8% received a hybrid procedure. There was a significant increase in endovascular procedures over time. The all-cause mortality was 7.1% with nrTAAA and 55% with rTAAA. The mortality was lower for rTAAA when f/bEVAR or hybrid procedures were used. A ruptured aneurysm and higher comorbidity were associated with higher hospital mortality. This study demonstrates that the treatment approach has changed significantly over the observed period. The use of f/bEVAR nearly tripled in nrTAAA and doubled in rTAAA during this decade.

Long-Term Outcomes in Thoracic Endovascular Aortic Repair for Complicated Type B Aortic Dissection or Intramural Hematoma Depending on Proximal Landing Zone.

Thoracic endovascular aortic repair (TEVAR) is the preferred treatment for complicated type B aortic dissection (TBAD) or intramural hematoma (IMH). This study aimed to investigate the association of the proximal landing zone and its morphology with long-term outcomes in patients with TBAD or IMH. A total of 94 patients who underwent TEVAR for TBAD or IMH between 10/2003 and 01/2020 were included. The cohort was divided according to the proximal landing in Ishimaru zone 2 or 3 and the presence of a healthy landing zone (HLZ; non-dissected or aneurysmatic, ≥2 cm length). Primary outcome was freedom from aortic reintervention. Secondary endpoints were freedom from aortic growth, stroke, spinal cord ischemia, retrograde dissection, proximal stent-graft induced new entry (pSINE), debranching failure, and mortality. Outcomes were assessed using Cox proportional hazard models with mortality as a competing risk. A proximal TEVAR landing in zone 2 was associated with higher rates of reinterventions compared to zone 3 (33% vs. 15%, p = 0.031), spinal cord ischemia (8% vs. 0%, p = 0.037), and pSINE (13% vs. 2%, p = 0.032). No difference was found for the other outcomes, including mortality. Landing in dissected segments was not associated with impaired results. Proximal TEVAR landing in zone 3 may be preferable with regard to long-term aortic reintervention in patients with TBAD or IMH.

Patients with Acute Limb Ischemia Might Benefit from Endovascular Therapy-A 17-Year Retrospective Single-Center Series of 985 Patients.

Acute lower limb ischemia (ALI) is a common vascular emergency, requiring urgent revascularization by open or endovascular means. The aim of this retrospective study was to evaluate patient demographics, treatment and periprocedural variables affecting the outcome in ALI patients in a consecutive cohort in a tertiary referral center. Primary outcome events (POE) were 30-day (safety) and 180-day (efficacy) combined mortality and major amputation rates, respectively. Secondary outcomes were perioperative medical and surgical leg-related complications and the 5-year combined mortality and major amputation rate. Statistical analysis used descriptive and uni- and multivariable Cox regression analysis. In 985 patients (71 ± 9 years, 56% men) from 2004 to 2020, the 30-day and 180-day combined mortality and major amputation rates were 15% and 27%. Upon multivariable analysis, older age (30 d: aHR 1.17; 180 d: 1.27) and advanced Rutherford ischemia stage significantly worsened the safety and efficacy POE (30 d: TASC IIa aHR 3.29, TASC IIb aHR 3.93, TASC III aHR 7.79; 180 d: TASC IIa aHR 1.97, TASC IIb aHR 2.43, TASC III aHR 4.2), while endovascular treatment was associated with significant improved POE after 30 days (aHR 0.35) and 180 days (aHR 0.39), respectively. Looking at five consecutive patient quintiles, a significant increase in endovascular procedures especially in the last quintile could be observed (17.5% to 39.5%, p < 0.001). Simultaneously, the re-occlusion rate as well as the number of patients with any previous revascularization increased. In conclusion, despite a slightly increasing early re-occlusion rate, endovascular treatment might, if possible, be favorable in ALI treatment.

Biobanking: Objectives, Requirements, and Future Challenges-Experiences from the Munich Vascular Biobank.

Collecting biological tissue samples in a biobank grants a unique opportunity to validate diagnostic and therapeutic strategies for translational and clinical research. In the present work, we provide our long-standing experience in establishing and maintaining a biobank of vascular tissue samples, including the evaluation of tissue quality, especially in formalin-fixed paraffin-embedded specimens (FFPE). Our Munich Vascular Biobank includes, thus far, vascular biomaterial from patients with high-grade carotid artery stenosis (n = 1567), peripheral arterial disease (n = 703), and abdominal aortic aneurysm (n = 481) from our Department of Vascular and Endovascular Surgery (January 2004⁻December 2018). Vascular tissue samples are continuously processed and characterized to assess tissue morphology, histological quality, cellular composition, inflammation, calcification, neovascularization, and the content of elastin and collagen fibers. Atherosclerotic plaques are further classified in accordance with the American Heart Association (AHA), and plaque stability is determined. In order to assess the quality of RNA from FFPE tissue samples over time (2009⁻2018), RNA integrity number (RIN) and the extent of RNA fragmentation were evaluated. Expression analysis was performed with two housekeeping genes-glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and beta-actin (ACTB)-using TaqMan-based quantitative reverse-transcription polymerase chain reaction (qRT)-PCR. FFPE biospecimens demonstrated unaltered RNA stability over time for up to 10 years. Furthermore, we provide a protocol for processing tissue samples in our Munich Vascular Biobank. In this work, we demonstrate that biobanking is an important tool not only for scientific research but also for clinical usage and personalized medicine.