Inflammatory abdominal aortic aneurysms: A case-control study

AbstractPurpose: This study was designed to identify significant differences in the clinical and radiologic characteristics and outcome between patients with inflammatory and noninflammatory abdominal aortic aneurysms (AAAs).Methods: We reviewed 29 consecutive patients who underwent repair of an inflammatory AAA between 1985 and 1994. This group was matched in a case-control fashion by date of surgery and by the performing surgeon to a group of 58 patients who underwent repair of noninflammatory AAAs.Results: The two groups had comparable characteristics of age, gender, and cardiovascular risk factors. Patients with inflammatory AAAs were significantly more symptomatic than those with noninflammatory AAAs (93% vs 9%, p < 0.001), were more likely to have a family history of aneurysms (17% vs 1.5%, p = 0.007), and tended to be current smokers (45% vs 24%, p = 0.049). Thi most significant laboratory difference was an elevated sedimentation rate in patients with inflammatory AAAs (mean, 53 mm/hr vs 12 mm/hr, p < 0.00001). Inflammatory AAAs also were significantly larger than noninflammatory AAAs at presentation (6.8 cm vs 5.9 cm, p < 0.05). Although operative mortality was low in both groups, patients with an inflammatory AAA tended to have higher morbidity, including sepsis ( p < 0.01) and renal failure ( p = 0.04). Five-year survival rates, however, were similar for the two groups (79% for inflammatory and 83% for noninflammatory AAAs). On follow-up computed tomographic scans, the retroperitoneal inflammatory process resolved completely in 53% of the patients, but 47% of patients had persistent inflammation that involved the ureters in 32% and resulted in long-term solitary or bilateral renal atrophy in 47%.Conclusions: This case-control study provides preliminary evidence that inflammatory AAAs may have a relatively strong familial connection and that current smoking may play an important role in the inflammatory response. The study also documents that persistent retroperitoneal inflammation may be more prevalent than has been previously reported, and stresses the need for an improved understanding of the pathogenesis and long-term management of inflammatory AAAs. (J Vasc Surg 1996;23:860-9.

Vascular endothelial growth factor (VEGF) fails to improve blood flow and to promote collateralization in a diabetic mouse ischemic hindlimb model

BACKGROUND: Angiogenic therapy with vascular endothelial growth factor (VEGF) has been proposed as a treatment paradigm for patients suffering from an insufficiency of collateral vessels. Diabetes is associated with increase in the production of VEGF and therefore additional VEGF may not be beneficial. Accordingly, we sought to determine the efficacy of VEGF therapy to augment collateral formation and tissue perfusion in a diabetic mouse ischemic hindlimb model. METHODS: Diabetic and non-diabetic mice were studied in parallel for the efficacy of VEGF administration. Diabetes was induced with streptozotocin. Hindlimb ischemia was produced by severing the left iliac artery. An outlet tube from an osmotic infusion pump with placebo/ 500 micrograms of plasmid-DNA encoding VEGF was fenestrated and tunneled into the left quadriceps muscle. RESULTS: VEGF induced more rapid and complete restoration of blood flow in normal mice. However, in the setting of diabetes there was no difference between VEGF Vs. placebo in the rate or adequacy of flow restoration. There was a significant increase in smooth muscle actin and Factor-VIII antigen densities in diabetic animals and in animals which received VEGF. CONCLUSIONS: Angiogenic therapy with VEGF in the setting of diabetes does not appear to have the beneficial effects seen in the absence of diabetes

Inhibition of vein graft remodeling and neo-intimal formation using a cobalt chrome external support

Objective: Despite significant advances in the understanding of vein graft remodeling during the post-implantation, vein graft disease is still a major limitation of surgical revascularization. The study objective was to evaluate the performance of a new cobalt chrome external support device designed to mitigate vein graft remodeling and development of intimal hyperplasia. Methods: Bilateral carotid interposition of reversed saphenous vein graft segments was performed in seven&#8207; adult sheep. Following completion of the first anastomosis, randomization was performed to allocate the experimental and control grafts in each animal. Post-procedure, Doppler US was used to assess grafts lumen diameter at T0 and then 3-5 and 12-14 weeks after surgery. At 12-14 weeks, all sheep underwent angiography to assess grafts patency and lumen uniformity (coefficient of variance - CV) after which they were sacrificed, and all grafts were harvested for microscopic histological analysis. Results: Baseline (T0) internal diameter was not significantly different between the supported and unsupported grafts. At twelve to fourteen weeks, the internal diameter of supported grafts remained unchanged and was significantly lower compared to the non-supported grafts (6.6mm±0.4mm vs. 12.8mm±4.0mm respectively, p= 0.0001). Percentage coefficient of variance (%CV) was 4.6%±4.3 in the supported grafts as opposed to average CV% of 14.7%±6.5 in the non-stented group (p=0.011). Neointimal area was significantly lower in the stented compared to the non-stented group (1.4 mm2±3.3mm2 versus 9.6mm2±9.7mm2 respectively, p=0.009). Conclusions: External support of vein grafts using a braided cobalt chrome external stent reduces early vein graft remodeling and mitigates the development of neointimal hyperplasia. [Arch Clin Exp Surg 2018; 7(3.000): 108-115