A Complicated Entity: Acute Celiac Artery Dissection with Resultant Pancreatitis, Duodenitis, and Cholecystitis.

Arterial dissection is a well-recognized pathology often seen in Vascular Surgery offices and Emergency Departments alike; however, visceral arterial dissection is an extremely rare, small subset of this entity. With that, an isolated celiac artery dissection as presented within this report is an exceptionally unique pathology that has scarcely been reported, and due to this, management guidelines are undefined. Given the viscera supplied by the celiac artery, many intra-abdominal structures are at risk for ischemia when damage to the celiac artery occurs, potentially witnessed by this report. Due to the exclusivity of this pathology, we are compelled to report the case of a 71-year-old male who presented with complaints of abdominal pain and was found to have an acute celiac artery dissection, which likely resulted in severe ischemic duodenitis, as well as possibly acute pancreatitis, and questionable influence on cholecystitis.

Novel pathways in the pathobiology of human abdominal aortic aneurysms.

OBJECTIVES: Abdominal aortic aneurysm (AAA), a dilatation of the infrarenal aorta, typically affects males >65 years. The pathobiological mechanisms of human AAA are poorly understood. The goal of this study was to identify novel pathways involved in the development of AAAs. METHODS: A custom-designed 'AAA-chip' was used to assay 43 of the differentially expressed genes identified in a previously published microarray study between AAA (n = 15) and control (n = 15) infrarenal abdominal aorta. Protein analyses were performed on selected genes. RESULTS: Altogether 38 of the 43 genes on the 'AAA-chip' showed significantly different expression. Novel validated genes in AAA pathobiology included ADCY7, ARL4C, BLNK, FOSB, GATM, LYZ, MFGE8, PRUNE2, PTPRC, SMTN, TMODI and TPM2. These genes represent a wide range of biological functions, such as calcium signaling, development and differentiation, as well as cell adhesion not previously implicated in AAA pathobiology. Protein analyses for GATM, CD4, CXCR4, BLNK, PLEK, LYZ, FOSB, DUSP6, ITGA5 and PTPRC confirmed the mRNA findings. CONCLUSION: The results provide new directions for future research into AAA pathogenesis to study the role of novel genes confirmed here. New treatments and diagnostic tools for AAA could potentially be identified by studying these novel pathways.

MicroRNA expression signature in human abdominal aortic aneurysms.

BACKGROUND: Abdominal aortic aneurysm (AAA) is a dilatation of the aorta affecting most frequently elderly men. Histologically AAAs are characterized by inflammation, vascular smooth muscle cell apoptosis, and extracellular matrix degradation. The mechanisms of AAA formation, progression, and rupture are currently poorly understood. A previous mRNA expression study revealed a large number of differentially expressed genes between AAA and non-aneurysmal control aortas. MicroRNAs (miRNAs), small non-coding RNAs that are post-transcriptional regulators of gene expression, could provide a mechanism for the differential expression of genes in AAA. METHODS: To determine differences in miRNA levels between AAA (n = 5) and control (n = 5) infrarenal aortic tissues, a microarray study was carried out. Results were adjusted using Benjamini-Hochberg correction (adjusted p < 0.05). Real-time quantitative RT-PCR (qRT-PCR) assays with an independent set of 36 AAA and seven control tissues were used for validation. Potential gene targets were retrieved from miRNA target prediction databases Pictar, TargetScan, and MiRTarget2. Networks from the target gene set were generated and examined using the network analysis programs, CytoScape® and Ingenuity Pathway Core Analysis®. RESULTS: A microarray study identified eight miRNAs with significantly different expression levels between AAA and controls (adjusted p < 0.05). Real-time qRT-PCR assays validated the findings for five of the eight miRNAs. A total of 222 predicted miRNA target genes known to be differentially expressed in AAA based on a prior mRNA microarray study were identified. Bioinformatic analyses revealed that several target genes are involved in apoptosis and activation of T cells. CONCLUSIONS: Our genome-wide approach revealed several differentially expressed miRNAs in human AAA tissue suggesting that miRNAs play a role in AAA pathogenesis.

Regional expression of HOXA4 along the aorta and its potential role in human abdominal aortic aneurysms.

BACKGROUND: The infrarenal abdominal aorta exhibits increased disease susceptibility relative to other aortic regions. Allograft studies exchanging thoracic and abdominal segments showed that regional susceptibility is maintained regardless of location, suggesting substantial roles for embryological origin, tissue composition and site-specific gene expression. RESULTS: We analyzed gene expression with microarrays in baboon aortas, and found that members of the HOX gene family exhibited spatial expression differences. HOXA4 was chosen for further study, since it had decreased expression in the abdominal compared to the thoracic aorta. Western blot analysis from 24 human aortas demonstrated significantly higher HOXA4 protein levels in thoracic compared to abdominal tissues (P < 0.001). Immunohistochemical staining for HOXA4 showed nuclear and perinuclear staining in endothelial and smooth muscle cells in aorta. The HOXA4 transcript levels were significantly decreased in human abdominal aortic aneurysms (AAAs) compared to age-matched non-aneurysmal controls (P < 0.00004). Cultured human aortic endothelial and smooth muscle cells stimulated with INF-γ (an important inflammatory cytokine in AAA pathogenesis) showed decreased levels of HOXA4 protein (P < 0.0007). CONCLUSIONS: Our results demonstrated spatial variation in expression of HOXA4 in human aortas that persisted into adulthood and that downregulation of HOXA4 expression was associated with AAAs, an important aortic disease of the ageing population.

Management of arterial and venous injuries in the dislocated knee.

Although uncommonly encountered, knee dislocation is frequently associated with major vascular injury. Serious injuries resulting in ischemia demand prompt recognition and efficient management to prevent devastating long-term sequelae. In this review, we detail mechanisms of knee dislocation and associated popliteal vascular injuries. Diagnostic modalities used to evaluate the extent of vascular injury are individually discussed. Appropriate initial management of vascular injuries is crucial and an algorithm for diagnosis and management will be reviewed. We elaborate on the salient points of vascular reconstruction in the context of the dislocated knee: surgical approach, conduct of the procedure, and adjunctive maneuvers are described.

Role of complement cascade in abdominal aortic aneurysms.

OBJECTIVE: The goal of this study was to investigate the role of complement cascade genes in the pathobiology of human abdominal aortic aneurysms (AAAs). METHODS AND RESULTS: Results of a genome-wide microarray expression profiling revealed 3274 differentially expressed genes between aneurysmal and control aortic tissue. Interestingly, 13 genes in the complement cascade were significantly differentially expressed between AAA and the controls. In silico analysis of the promoters of the 13 complement cascade genes showed enrichment for transcription factor binding sites for signal transducer and activator of transcription (STAT)5A. Chromatin-immunoprecipitation experiments demonstrated binding of transcription factor STAT5A to the promoters of the majority of the complement cascade genes. Immunohistochemical analysis showed strong staining for C2 in AAA tissues. CONCLUSIONS: These results provide strong evidence that the complement cascade plays a role in human AAA. Based on our microarray studies, the pathway is activated in AAA, particularly via the lectin and classical pathways. The overrepresented binding sites of transcription factor STAT5A in the complement cascade gene promoters suggest a role for STAT5A in the coordinated regulation of complement cascade gene expression.

Treatment of a celiac artery aneurysm with endovascular stent grafting--a case report.

As a result of more sophisticated and more commonly performed investigative procedures, aneurysms of the visceral abdominal vasculature, including celiac artery aneurysms, are increasingly recognized. Traditional therapy for visceral artery aneurysms has been limited to open aneurysmectomy or aneurysmorrhaphy to prevent catastrophic aneurysmal rupture. However, these procedures are associated with significant postoperative morbidity and mortality despite technical successes. High complication rates are likely related to poor preoperative conditions among the patient population typically presenting with these visceral artery aneurysms. This report introduces an alternative therapy for visceral artery aneurysms and highlights the potential for catheter-based interventions. This case report depicts a 61-year-old morbidly obese woman diagnosed with a 10-centimeter celiac artery aneurysm during investigation of upper abdominal pain. Given the patient's poor medical condition, punctuated by hemodynamic instability, open operation was avoided, and percutaneous embolization was not feasible owing to a large aneurysm neck. Therefore, inflow to the celiac artery aneurysm was excluded by placing a modular stent graft component within the abdominal aorta at the celiac artery orifice. During the intervening 12 months since stent graft deployment, the aneurysm sac diameter has steadily decreased, as determined by serial computed tomography scans. This report underscores the potential for catheter-based techniques to offer new therapeutic options for patients with visceral artery aneurysms. Careful individualization is required given the highly variable size, location, and character of such lesions.