Comparative effectiveness of open surgery versus endovascular repair for hemodynamically stable and unstable ruptured abdominal aortic aneurysm

Bioinformatics Analysis Reveals the Potential Diagnostic Biomarkers for Abdominal Aortic Aneurysm

Objectives: Abdominal aortic aneurysms (AAAs) are associated with high mortality rates. The genes and pathways linked with AAA remain poorly understood. This study aimed to identify key differentially expressed genes (DEGs) linked to the progression of AAA using bioinformatics analysis.

Methods: Gene expression profiles of the GSE47472 and GSE57691 datasets were acquired from the Gene Expression Omnibus (GEO) database. These datasets were merged and normalized using the “sva” R package, and DEGs were identified using the limma package in R. The functions of these DEGs were assessed using Cytoscape software. We analyzed the DEGs using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. Protein–protein interaction networks were assembled using Cytoscape, and crucial genes were identified using the Cytoscape plugin, molecular complex detection. Data from GSE15729 and GSE24342 were also extracted to verify our findings.

Results: We found that 120 genes were differentially expressed in AAA. Genes associated with inflammatory responses and nuclear-transcribed mRNA catabolic process were clustered in two gene modules in AAA. The hub genes of the two modules were IL6, RPL21, and RPL7A. The expression levels of IL6 correlated positively with RPL7A and negatively with RPL21. The expression of RPL21 and RPL7A was downregulated, whereas that of IL6 was upregulated in AAA.

Conclusions: The expression of RPL21 or RPL7A combined with IL6 has a diagnostic value for AAA. The novel DEGs and pathways identified herein might provide new insights into the underlying molecular mechanisms of AAA.

Editor's Choice - Systematic Review and Meta-Analysis of the Effect of Weekend Admission on Outcomes for Ruptured Abdominal Aortic Aneurysms: A Call for an Equitable Seven Day Vascular Service

OBJECTIVE

"The weekend effect" of higher patient mortality when presenting at a weekend compared with a weekday has been established for several conditions. The aim of this study was to investigate whether a weekend effect exists for the emergency condition of ruptured abdominal aortic aneurysm.

DATA SOURCES

A review of the literature was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines (PROSPERO registration number CRD42020157484). MEDLINE, EMBASE and CINAHL were searched using the Healthcare Databases Advanced Search interface developed by NICE.

REVIEW METHODS

The prognostic factor of interest was weekend admission. The primary outcome of interest was all cause peri-operative mortality, with a secondary outcome of hospital length of stay. A random effects meta-analysis was performed, and the results were reported as summary odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Twelve observational cohort studies published between 2001 and 2019 comprising 14 patient cohorts with a total of 95 856 patients were eligible for quantitative synthesis. Patients presenting on a weekend had a significantly higher risk of unadjusted in hospital mortality (OR 1.20, 95% CI 1.10 - 1.31, p < .001). Both the unadjusted 30 day mortality risk (OR 1.16, 95% CI 0.98 - 1.39, p = .090) and unadjusted 90 day mortality risk (OR 1.12, 95% CI 0.90 - 1.40, p = .30) were higher for those presenting at a weekend, but neither reached statistical significance. There was a significantly greater risk of combined unadjusted in hospital, 30 and 90 day mortality for those presenting at a weekend (OR 1.17, 95% CI 1.09 - 1.27, p < .001). Hospital length of stay was not statistically different between groups.

CONCLUSION

There is an association between weekend admission and higher mortality in patients presenting with ruptured abdominal aortic aneurysm.

Role of intraluminal thrombus in abdominal aortic aneurysm ruptures: A hemodynamic point of view

PURPOSE

Intraluminal thrombus (ILTs) are found in most abdominal aortic aneurysms (AAAs) of clinically relevant size; however, the role of ILTs in AAA ruptures remains unclear. This study investigated the role of the presence and thickness of ILTs in AAA ruptures by analyzing the hemodynamic environment in ruptured AAAs (RAAAs).

METHODS

Three-dimensional reconstructions from computed tomography scans were performed, and 13 RAAA cases were categorized into a no-ILT group, a thin-layered ILT group (thickness < 3 mm), and a thick-layered ILT group. The hemodynamic features of the RAAAs were assessed using computational fluid dynamics simulation.

RESULTS

The thin- and thick-layered ILT groups showed significant differences in aneurysm diameters (P < 0.05). The three types of AAAs ruptured at different flow regions, with different hemodynamic features: (a) the no-ILT AAAs ruptured at regions of flow recirculation where velocity and wall shear stresses (WSSs) were close to zero; (b) the thin-layered ILT AAAs ruptured at sites at which the dominant flow impinged the wall; and (c) the thick-layered ILT AAAs ruptured at the border of the dominant flow channel and recirculation zone where the flow velocity and pressure changed dramatically.

CONCLUSIONS

Hemodynamic characteristics influence the rupture mechanisms of particular AAAs differently on the basis of the presence and thickness of ILTs. Recirculation flows and low WSSs may have negative effects by inducing local rupture or positive effects by promoting the formation of thin-layered ILTs. However, eccentrically located thick-layered ILTs may increase the rupture risk of small AAAs because of their location in the sac lumen, which results in chaotic flow patterns and rapid increases in flow resistance.

Open Repair of a Ruptured Abdominal Aortic Aneurysm on a Patient Under Rivaroxaban and Clopidogrel

BACKGROUND

Direct oral anticoagulants are commonly used instead of vitamin K antagonists in patients needing long-term anticoagulant treatment. As their use has become more popular, there is an increase possibility to perform a major surgery on an urgent or emergency basis on patients under nonvitamin-K antagonist oral anticoagulants.

CASE REPORT

We report a case of a ruptured abdominal aortic aneurysm on a male patient under rivaroxaban and clopidogrel. Emergency open repair of the aneurysm was performed. No anti-Xa antidote was administered. The patient had an uneventful recovery.

CONCLUSION

An open repair of a ruptured abdominal aortic aneurysm under rivaroxaban is feasible. However, an antidote should be available in cases of uncontrolled diffused bleeding. To the best of our knowledge, this is the first reported case of successful open repair of a ruptured abdominal aortic aneurysm on a patient under rivaroxaban and clopidogrel.