[Clinical data analysis of 117 patients with ruptured abdominal aortic aneurysm].

Objective: To examine the perioperative clinical features and prognosis of patients with ruptured abdominal aortic aneurysms (rAAA) who received surgical repair. Methods: The clinical data of rAAA patients who underwent surgical repair and were admitted to the Surgical Intensive Care Unit of Beijing Anzhen Hospital, Capital Medical University from August 2005 to November 2020 were retrospectively analyzed, including the general clinical features, surgical mode, intraoperative conditions, postoperative complications, and fatality rate. Results: There were 117 patients with rAAA, with a median age of 68 (62,77) years, including 93 men (79.5%) and 24 women (20.5%). The main clinical manifestation was abdominal pain (n=115, 98.3%). Among them, 65 (55.6%) patients underwent endovascular aneurysm repair (EVAR), while 52 (44.4%) underwent open surgical repair (OSR). The common postoperative complications include acute gastrointestinal dysfunction (n=116, 99.1%), shock (n=89, 76.1%), acute respiratory distress syndrome (n=85, 72.6%), pancreatic injury (n=56, 47.9%), coagulation dysfunction (n=55, 47.0%), disseminated intravascular coagulation (n=46, 39.3%), acute kidney injury (n=39, 33.3%), infection/sepsis (n=28, 23.9%), gastrointestinal bleeding (n=17, 14.5%), and abdominal compartment syndrome (n=12, 10.3%). The overall postoperative in-hospital fatality rate was 10.3% (12/117). Preoperative use of vasopressors and inotropes, retroperitoneal hematoma, and postoperative abdominal compartment syndrome, gastrointestinal hemorrhage, acute kidney injury, and diffuse intravascular coagulation significantly increased the fatality rate [5/11, 6/24, 5/16, 6/12, 6/17, 23.1%(9/39), 19.6%(9/46), respectively]. Conclusion: The postoperative mortality of rAAA patients is still high in the era of EVAR, especially in patients with preoperative existence of shock and retroperitoneal hematoma, and with postoperative abdominal compartment syndrome, coagulation dysfunction, and acute kidney injury. It is necessary to strengthen perioperative monitoring and management of these patients to reduce the fatality rate.

Comment on Rehman et al. "Short-Term Outcomes of Elective Abdominal Aortic Aneurysm Repair".

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Extravertebral low back pain: a scoping review.

BACKGROUND: Low back pain (LBP) is one of the most common reasons for consultation in general practice. Currently, LBP is categorised into specific and non-specific causes. However, extravertebral causes, such as abdominal aortic aneurysm or pancreatitis, are not being considered. METHODS: A systematic literature search was performed across MEDLINE, Embase, and the Cochrane library, complemented by a handsearch. Studies conducted between 1 January 2001 and 31 December 2020, where LBP was the main symptom, were included. RESULTS: The literature search identified 6040 studies, from which duplicates were removed, leaving 4105 studies for title and abstract screening. Subsequently, 265 publications were selected for inclusion, with an additional 197 publications identified through the handsearch. The majority of the studies were case reports and case series, predominantly originating from specialised care settings. A clear distinction between vertebral or rare causes of LBP was not always possible. A range of diseases were identified as potential extravertebral causes of LBP, encompassing gynaecological, urological, vascular, systemic, and gastrointestinal diseases. Notably, guidelines exhibited inconsistencies in addressing extravertebral causes. DISCUSSION: Prior to this review, there has been no systematic investigation into extravertebral causes of LBP. Although these causes are rare, the absence of robust and reliable epidemiological data hinders a comprehensive understanding, as well as the lack of standardised protocols, which contributes to a lack of accurate description of indicative symptoms. While there are certain disease-specific characteristics, such as non-mechanical or cyclical LBP, and atypical accompanying symptoms like fever, abdominal pain, or leg swelling, that may suggest extravertebral causes, it is important to recognise that these features are not universally present in every patient. CONCLUSION: The differential diagnosis of extravertebral LBP is extensive with relatively low prevalence rates dependent on the clinical setting. Clinicians should maintain a high index of suspicion for extravertebral aetiologies, especially in patients presenting with atypical accompanying symptoms.

[Preventive myocardial revascularization prior to abdominal aortic repair in patients without cardiac symptoms: long-term results]. / Profilakticheskaya revaskulyarizatsiya miokarda pered rezektsiei anevrizmy bryushnoi aorty u kardiologicheski asimptomnykh bol'nykh: otdalennye rezul'taty.

OBJECTIVE: To evaluate the long-term influence of preoperative invasive coronary screening and preventive myocardial revascularization on mortality and cardiac complications after open surgery for abdominal aortic aneurysms (AAA). MATERIAL AND METHODS: We present long-term outcomes after open surgery for AAA between 2011 and 2022. Patients without clinical or objective signs of coronary artery disease were included. In the 1st group, routine coronary angiography was performed before surgery. Prophylactic myocardial revascularization was performed in 12 cases. Long-term data on 45 patients were obtained. In the 2nd group, 53 patients underwent repair without invasive coronary screening, and data on 48 patients were obtained in this group. RESULTS: The median follow-up was 32 and 79 months, respectively. Kaplan-Meyer overall 48-month survival was 87.3% and 82.1%, respectively (p=0.278). In the first group, 2 patients developed angina pectoris in the same period. In the second group, we observed 2 cases of myocardial infarction and 3 cases of angina pectoris without infarction. Analysis of survival curves found no significant differences (p=0.165). CONCLUSION: In our study, invasive coronary screening and preventive myocardial revascularization in patients without clinical and objective signs of coronary artery did not improve 4-year long-term period after abdominal aortic repair. Perhaps, differences will appear after 4 years, and this requires further follow-up after coronary angiography. However, there is a tendency towards more common onsets of coronary artery disease that dictates the need for cardiac monitoring of such patients.

Extravascular administration of IGF1R antagonists protects against aortic aneurysm in rodent and porcine models.

An abdominal aortic aneurysm (AAA) is a life-threatening cardiovascular disease. We identified plasma insulin-like growth factor 1 (IGF1) as an independent risk factor in patients with AAA by correlating plasma IGF1 with risk. Smooth muscle cell- or fibroblast-specific knockout of Igf1r, the gene encoding the IGF1 receptor (IGF1R), attenuated AAA formation in two mouse models of AAA induced by angiotensin II infusion or CaCl2 treatment. IGF1R was activated in aortic aneurysm samples from human patients and mice with AAA. Systemic administration of IGF1C, a peptide fragment of IGF1, 2 weeks after disease development inhibited AAA progression in mice. Decreased AAA formation was linked to competitive inhibition of IGF1 binding to its receptor by IGF1C and modulation of downstream alpha serine/threonine protein kinase (AKT)/mammalian target of rapamycin signaling. Localized application of an IGF1C-loaded hydrogel was developed to reduce the side effects observed after systemic administration of IGF1C or IGF1R antagonists in the CaCl2-induced AAA mouse model. The inhibitory effect of the IGF1C-loaded hydrogel administered at disease onset on AAA formation was further evaluated in a guinea pig-to-rat xenograft model and in a sheep-to-minipig xenograft model of AAA formation. The therapeutic efficacy of IGF1C for treating AAA was tested through extravascular delivery in the sheep-to-minipig model with AAA established for 2 weeks. Percutaneous injection of the IGF1C-loaded hydrogel around the AAA resulted in improved vessel flow dynamics in the minipig aorta. These findings suggest that extravascular administration of IGF1R antagonists may have translational potential for treating AAA.

Mortality and hospitalization trends for aortic aneurysms and dissections in Mexico.

BACKGROUND: In Mexico, there is a paucity of evidence on mortality and hospitalization patterns associated with aortic aneurysms and dissections. OBJECTIVE: To analyze national databases and describe the epidemiological characteristics of different aortic pathologies. MATERIAL AND METHODS: Retrospective, cross-sectional, observational study, in which mortality and hospitalization attributed to aortic aneurysms and dissections were analyzed. Statistical analysis was performed on Stata 16. RESULTS: A total of 6,049 deaths were documented in the general population, which included 2,367 hospitalizations and 476 (20.1%) in-hospital deaths. In addition, a statistically significant age difference was found between mean age at death in the general population (69.5 years) and the in-hospital death group (64.1 years, p < 0.001). As for hospitalizations secondary to ruptured abdominal aortic aneurysms, 149 cases were identified, with a mean age of 65.6 years, out of whom 53 (35.5%) were under 65 years of age, with a mean age of 47.8 years. CONCLUSIONS: Epidemiological reports of aortic pathology in Mexico are scarce; therefore, implementation of screening and detection programs for aortic pathologies is necessary in order to address the disparities identified in this analysis.

ANTECEDENTES: Existe evidencia escasa en México respecto a la mortalidad y patrones del ingreso hospitalario asociados a aneurismas y disecciones aórticos. OBJETIVO: Analizar las bases de datos nacionales y describir las características epidemiológicas de diferentes patologías aórticas agudas. MATERIAL Y MÉTODOS: Estudio transversal y observacional de una base de datos retrospectiva, en el que se analizó la mortalidad y hospitalización atribuidas a aneurismas y disecciones aórticos. El análisis estadístico se realizó en Stata 16. RESULTADOS: Se documentaron 6049 muertes en la población general, 2367 hospitalizaciones y 476 muertes intrahospitalarias. Adicionalmente, se encontró una diferencia estadísticamente significativa entre las medias de edad de fallecimiento de la población general (65.5 años) y de los pacientes que murieron en el hospital (64.1 años), p < 0.001. En cuanto a las hospitalizaciones secundarias a aneurisma de aorta abdominal roto, 149 casos fueron evidenciados con una media de edad de 65.6 años; 53 (35.5 %) de estos tenía menos de 65 años, con una media de edad de 47.8 años. CONCLUSIONES: Los reportes epidemiológicos de patología aórtica en México son escasos, por ello la implementación de programas de tamizaje y la detección de patologías aórticas son necesarias para mejorar las disparidades encontradas en este análisis.

Use of EndoAnchors during index endovascular aortic aneurysm repair in patients with hostile proximal aortic neck anatomy.

PURPOSE: Standard endovascular aortic aneurysm repair (EVAR) is sometimes the only treatment option for patients with hostile aortic neck anatomy, but it carries an increased risk of both early and late procedure-related complications. The aim of this study was to report on single-center experience with the Heli-FX EndoAnchors (Medtronic, Santa Rosa, CA) as an adjunctive procedure to endovascular aneurysm repair (EVAR) for prevention and perioperative treatment of proximal neck complications in patients with hostile neck anatomy.  MATERIALS AND METHODS: A single-centre, retrospective study evaluating 24 consecutive patients treated with EndoAnchors during the index EVAR procedure between November 2018 and August 2021. EndoAnchor implantation was indicated for cases with hostile proximal aortic neck anatomy characterised by the presence of at least one of the following parameters: length of 28 mm, angle of >60°, circumferential thrombus/calcification involving ≥50%, and reverse taper. RESULTS:  Median follow-up period was 22.5 months (IQR 2-31.5 months) with no aneurysm-related death, rupture, or conversion to open surgical repair during the follow-up. The procedural success rate was 100%, with no type Ia endoleak at the completion angiography. A mean of 7 EndoAnchors was used per patient (range 4-12). There were no EndoAnchor fractures and dislocations or stent graft fabric damage due to anchor implants. Twenty-three patients (95.8%) remained free of type Ia endoleak and migration on follow-up imaging. Aneurysm sac regression was observed in 13 patients (54.1%), while in 8 patients (33.3%) the sac remained stable. Sac enlargement was present in 1 patient (4.2%) due to late type Ia endoleak. Two patients were lost to the follow-up immediately after the procedure. Between two groups of patients (sac regression versus failure to regress), the larger initial diameter of the proximal neck was the only significant independent factor associated with a lower possibility of sac regression (p= 0,021). CONCLUSIONS:  The use of EndoAnchors during the index EVAR procedure in cases with challenging aortic neck anatomy with or without perioperative type Ia endoleak was associated with good midterm results and led to sac regression in most of the patients (Tab. 4, Fig. 3, Ref. 31).

Construction of ferroptosis-related prediction model for pathogenesis, diagnosis and treatment of ruptured abdominal aortic aneurysm.

Abdominal aortic aneurysm (AAA) is a dangerous cardiovascular disease, which often brings great psychological burden and economic pressure to patients. If AAA rupture occurs, it is a serious threat to patients' lives. Therefore, it is of clinical value to actively explore the pathogenesis of ruptured AAA and prevent its occurrence. Ferroptosis is a new type of cell death dependent on lipid peroxidation, which plays an important role in many cardiovascular diseases. In this study, we used online data and analysis of ferroptosis-related genes to uncover the formation of ruptured AAA and potential therapeutic targets. We obtained ferroptosis-related differentially expressed genes (Fe-DEGs) from GSE98278 dataset and 259 known ferroptosis-related genes from FerrDb website. Enrichment analysis of differentially expressed genes (DEGs) was performed by gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG). Receiver Operating characteristic (ROC) curve was employed to evaluate the diagnostic abilities of Fe-DEGs. Transcription factors and miRNAs of Fe-DEGs were identified through PASTAA and miRDB, miRWalk, TargetScan respectively. Single-sample gene set enrichment analysis (ssGSEA) was used to observe immune infiltration between the stable group and the rupture group. DGIdb database was performed to find potential targeted drugs of DEGs. GO and KEGG enrichment analysis found that DEGs mainly enriched in "cellular divalent inorganic cation homeostasis," "cellular zinc ion homeostasis," "divalent inorganic cation homeostasis," "Mineral absorption," "Cytokine - cytokine receptor interaction," "Coronavirus disease - COVID-19." Two up-regulated Fe-DEGs MT1G and DDIT4 were found to further analysis. Both single and combined applications of MT1G and DDIT4 showed good diagnostic efficacy (AUC = 0.8254, 0.8548, 0.8577, respectively). Transcription factors STAT1 and PU1 of MT1G and ARNT and MAX of DDIT4 were identified. Meanwhile, has_miR-548p-MT1G pairs, has_miR-53-3p/has_miR-181b-5p/ has_miR-664a-3p-DDIT4 pairs were found. B cells, NK cells, Th2 cells were high expression in the rupture group compared with the stable group, while DCs, Th1 cells were low expression in the rupture group. Targeted drugs against immunity, GEMCITABINE and INDOMETHACIN were discovered. We preliminarily explored the clinical significance of Fe-DEGs MT1G and DDIT4 in the diagnosis of ruptured AAA, and proposed possible upstream regulatory transcription factors and miRNAs. In addition, we also analyzed the immune infiltration of stable and rupture groups, and found possible targeted drugs for immunotherapy.

The Role of Inflammasome in Abdominal Aortic Aneurysm and Its Potential Drugs.

Abdominal aortic aneurysm (AAA) has been recognized as a serious chronic inflammatory degenerative aortic disease in recent years. At present, there is no other effective intervention except surgical treatment for AAA. With the aging of the human population, its incidence is increasing year by year, posing a serious threat to human health. Modern studies suggest that vascular chronic inflammatory response is the core process in AAA occurrence and development. Inflammasome, a multiprotein complex located in the cytoplasm, mediates the expression of various inflammatory cytokines like interleukin (IL)-1ß and IL-18, and thus plays a pivotal role in inflammation regulation. Therefore, inflammasome may exert a crucial influence on the progression of AAA. This article reviews some mechanism studies to investigate the role of inflammasome in AAA and then summarizes several potential drugs targeting inflammasome for the treatment of AAA, aiming to provide new ideas for the clinical prevention and treatment of AAA beyond surgical methods.

Successful chimney endovascular aortic repair with reconstruction of three visceral branches for huge saccular juxtarenal abdominal aortic aneurysm after trans-thoracoabdominal esophagectomy.

BACKGROUND: Conventional graft replacement for a juxtarenal abdominal aortic aneurysm (JRAAA) remains challenging for high-risk patients since it often requires the reconstruction of some visceral arteries. CASE PRESENTATION: A 76-year-old woman was diagnosed with an 87 × 48 mm saccular JRAAA. Open graft replacement was contraindicated because of frailty and a past history of trans-thoracoabdominal esophagectomy. Chimney endovascular aortic repair (ChEVAR) with three chimney endografts was successfully performed without any endoleaks, and each visceral circulation was kept intact. The patient was discharged uneventfully on postoperative day 8. Significant shrinkage of the aneurysmal sac and preservation of flow through each chimney graft were observed on computed tomography 6 months postoperatively, with no significant increase in serum creatinine levels on laboratory testing. CONCLUSIONS: ChEVAR can be a useful surgical option instead of conventional operations, especially for high-risk cases.

Focused abdominal ultrasound.

A focused point-of-care abdominal ultrasound is an examination performed at the patient's location and interpreted within the clinical context. This review gives an overview of this examination modality. The objective is to rapidly address predefined dichotomised questions about the presence of an abdominal aortic aneurysm, gallstones, cholecystitis, hydronephrosis, urinary retention, free intraperitoneal fluid, and small bowel obstruction. FAUS is a valuable tool for emergency physicians to promptly confirm various conditions upon the patients' arrival, thus reducing the time to diagnosis and in some cases eliminating the need for other imaging.

Design and Characterisation of a Read-Out System for Wireless Monitoring of a Novel Implantable Sensor for Abdominal Aortic Aneurysm Monitoring.

Abdominal aortic aneurysm (AAA) is a dilation of the aorta artery larger than its normal diameter (>3 cm). Endovascular aneurysm repair (EVAR) is a minimally invasive treatment option that involves the placement of a graft in the aneurysmal portion of the aorta artery. This treatment requires multiple follow-ups with medical imaging, which is expensive, time-consuming, and resource-demanding for healthcare systems. An alternative solution is the use of wireless implantable sensors (WIMSs) to monitor the growth of the aneurysm. A WIMS capable of monitoring aneurysm size longitudinally could serve as an alternative monitoring approach for post-EVAR patients. This study has developed and characterised a three-coil inductive read-out system to detect variations in the resonance frequency of the novel Z-shaped WIMS implanted within the AAA sac. Specifically, the spacing between the transmitter and the repeater inductors was optimised to maximise the detection of the sensor by the transmitter inductor. Moreover, an experimental evaluation was also performed for different orientations of the transmitter coil with reference to the WIMS. Finally, the FDA-approved material nitinol was used to develop the WIMS, the transmitter, and repeater inductors as a proof of concept for further studies. The findings of the characterisation from the air medium suggest that the read-out system can detect the WIMS up to 5 cm, regardless of the orientation of the Z-shape WIMS, with the detection range increasing as the orientation approaches 0°. This study provides sufficient evidence that the proposed WIMS and the read-out system can be used for AAA expansion over time.

Diagnostic value of uric acid to high-density lipoprotein cholesterol ratio in abdominal aortic aneurysms.

BACKGROUND: Abdominal aortic aneurysm (AAA) is highly lethal upon onset of acute aortic diseases (AAD) or rupture. Dyslipidaemia and hyperuricaemia are important risk factors for the development of AAA and AAD as well as aortic disease-related death. The aim of this study was to explore whether uric acid (UA) to high-density lipoprotein cholesterol (HDL-C) ratio (UHR) can be used as an independent predictor of the presence of AAA or AAD. METHODS: Three hundred subjects, including 100 AAA patients (AAA group), 100 AAD patients (AAD group) and 100 controls (CON group), were recruited in this study. UHR and other serum samples were obtained upon the patients' admission before any medical treatment. The optimal cut-off points of UHR were determined using receiver operating characteristic (ROC) curve analysis. RESULTS: The UHR in AAA group was significantly higher than that in CON group, but there was no significant difference between AAD group and CON group. The optimal cut-off point of UHR for AAA was 7.78 (sensitivity 84.7%, specificity 62.4%, and AUC 0.811; p < 0.001), and UHR (OR: 1.122, 95%CI: 1.064-1.184; p < 0.001) was found to be an independent factor for predicting AAA after adjusting for traditional AAA risk factor. CONCLUSION: UHR can be widely used in clinical practice as an auxiliary tool for screening AAA. The optimal cut-off point for UHR to AAA was determined for the first time in Chinese subjects.

Peak wall rupture index is associated with risk of rupture of abdominal aortic aneurysms, independent of size and sex.

BACKGROUND: Information on the predictive determinants of abdominal aortic aneurysm rupture from CT angiography are scarce. The aim of this study was to investigate biomechanical parameters in abdominal aortic aneurysms and their association with risk of subsequent rupture. METHODS: In this retrospective study, the digital radiological archive was searched for 363 patients with ruptured abdominal aortic aneurysms. All patients who underwent at least one CT angiography examination before aneurysm rupture were included. CT angiography results were analysed to determine maximum aneurysm diameter, aneurysm volume, and biomechanical parameters (peak wall stress and peak wall rupture index). In the primary survival analysis, patients with abdominal aortic aneurysms less than 70 mm were considered. Sensitivity analyses including control patients and abdominal aortic aneurysms of all sizes were performed. RESULTS: A total of 67 patients who underwent 109 CT angiography examinations before aneurysm rupture were identified. The majority were men (47, 70%) and the median age at the time of CTA examination was 77 (71-83) years. The median maximum aneurysm diameter was 56 (interquartile range 46-65) mm and the median time to rupture was 2.13 (interquartile range 0.64-4.72) years. In univariable analysis, maximum aneurysm diameter, aneurysm volume, peak wall stress, and peak wall rupture index were all associated with risk of rupture. Women had an increased HR for rupture when adjusted for maximum aneurysm diameter or aneurysm volume (HR 2.16, 95% c.i. 1.23 to 3.78 (P = 0.007) and HR 1.92, 95% c.i. 1.06 to 3.50 (P = 0.033) respectively). In multivariable analysis, the peak wall rupture index was associated with risk of rupture. The HR for peak wall rupture index was 1.05 (95% c.i. 1.03 to 1.08) per % (P < 0.001) when adjusted for maximum aneurysm diameter and 1.05 (95% c.i. 1.02 to 1.08) per % (P < 0.001) when adjusted for aneurysm volume. CONCLUSION: Biomechanical factors appear to be important in the prediction of abdominal aortic aneurysm rupture. Women are at increased risk of rupture when adjustments are made for maximum aneurysm diameter alone.

Identification of biomarkers for abdominal aortic aneurysm in Behçet's disease via mendelian randomization and integrated bioinformatics analyses.

Behçet's disease (BD) is a complex autoimmune disorder impacting several organ systems. Although the involvement of abdominal aortic aneurysm (AAA) in BD is rare, it can be associated with severe consequences. In the present study, we identified diagnostic biomarkers in patients with BD having AAA. Mendelian randomization (MR) analysis was initially used to explore the potential causal association between BD and AAA. The Limma package, WGCNA, PPI and machine learning algorithms were employed to identify potential diagnostic genes. A receiver operating characteristic curve (ROC) for the nomogram was constructed to ascertain the diagnostic value of AAA in patients with BD. Finally, immune cell infiltration analyses and single-sample gene set enrichment analysis (ssGSEA) were conducted. The MR analysis indicated a suggestive association between BD and the risk of AAA (odds ratio [OR]: 1.0384, 95% confidence interval [CI]: 1.0081-1.0696, p = 0.0126). Three hub genes (CD247, CD2 and CCR7) were identified using the integrated bioinformatics analyses, which were subsequently utilised to construct a nomogram (area under the curve [AUC]: 0.982, 95% CI: 0.944-1.000). Finally, the immune cell infiltration assay revealed that dysregulation immune cells were positively correlated with the three hub genes. Our MR analyses revealed a higher susceptibility of patients with BD to AAA. We used a systematic approach to identify three potential hub genes (CD247, CD2 and CCR7) and developed a nomogram to assist in the diagnosis of AAA among patients with BD. In addition, immune cell infiltration analysis indicated the dysregulation in immune cell proportions.

Increasing Use of Prophylactic Open Abdomen Therapy With Vacuum Assisted Wound Closure and Mesh Mediated Fascial Traction After Repair of Ruptured Abdominal Aortic Aneurysm.

OBJECTIVE: Open abdomen therapy (OAT) is commonly used to prevent or treat abdominal compartment syndrome (ACS) in patients with ruptured abdominal aortic aneurysms (rAAAs). This study aimed to evaluate the incidence, treatment, and outcomes of OAT after rAAA from 2006 to 2021. Investigating data on resuscitation fluid, weight gain, and cumulative fluid balance could provide a more systematic approach to determining the timing of safe abdominal closure. METHODS: This was a single centre observational cohort study. The study included all patients treated for rAAA followed by OAT from October 2006 to December 2021. RESULTS: Seventy-two of the 244 patients who underwent surgery for rAAA received OAT. The mean age was 72 ± 7.85 years, and most were male (n = 61, 85%). The most frequent comorbidities were cardiac disease (n = 31, 43%) and hypertension (n = 31, 43%). Fifty-two patients (72%) received prophylactic OAT, and 20 received OAT for ACS (28%). There was a 25% mortality rate in the prophylactic OAT group compared with the 50% mortality in those who received OAT for ACS (p = .042). The 58 (81%) patients who survived until closure had a median of 12 (interquartile range [IQR] 9, 16.5) days of OAT and 5 (IQR 4, 7) dressing changes. There was one case of colocutaneous fistula and two cases of graft infection. All 58 patients underwent successful abdominal closure, with 55 (95%) undergoing delayed primary closure. In hospital survival was 85%. Treatment trends over time showed the increased use of prophylactic OAT (p ≤ .001) and fewer ACS cases (p = .03) assessed by Fisher's exact test. In multivariable regression analysis fluid overload and weight reduction predicted 26% of variability in time to closure. CONCLUSION: Prophylactic OAT after rAAA can be performed safely, with a high rate of delayed primary closure even after long term treatment.