Comparing the endothelialisation of extracellular matrix bioscaffolds with coated synthetic vascular graft materials.

INTRODUCTION: Existing synthetic vascular grafts have unacceptably high failure rates when replacing below knee arteries. In vitro endothelialisation is a technique, which has been shown to enhance the patency rates of below knee vascular grafts. Synthetic materials are however poor cellular substrates and must be combined with coatings to promote cellular growth and attachment. The most common coating clinically is fibrin-coated ePTFE. The aim of our study was to compare the endothelialisation of fibrin-coated ePTFE with novel extracellular matrix (ECM) biomaterials that we hypothesise will provide a superior substrate for cell growth. METHODS: Human endothelial cells were cultured on ECM scaffolds and fibrin-coated ePTFE. Uncoated Dacron and ePTFE acted as controls. The cells were examined for viability, phenotype, adhesion and proliferation. Cell morphology was accessed using scanning electron microscopy. RESULTS: Cells remained viable and produced von Willebrand factor on all substrates tested. ECM scaffolds and fibrin-modified ePTFE achieved statistically higher attachment efficiency when compared to both uncoated synthetic graft materials (p ≤ 0.001). At 90 min 80 ± 3.6% of cells had attached to the ECM scaffold compared to Dacron (30 ± 4.5%, n = 3) and ePTFE (33 ± 2.5%, n = 3). There was no difference in adhesion rates between ECM scaffolds and fibrin-coated ePTFE (p = 1.00). Endothelial cells proliferated fastest on ECM scaffolds when compared to all other materials tested (p < 0.001) and reached confluency on day seven. CONCLUSION: ECM bioscaffolds offer an improved substrate for promoting rapid endothelialisation compared to fibrin-coated ePTFE by combining firm cellular anchorage and superior cell expansion.

Successful Treatment of Acute on Chronic Mesenteric Ischaemia by Common Iliac to Inferior Mesenteric Artery Bypass.

Chronic mesenteric ischaemia is a rare and potentially fatal condition most commonly due to atherosclerotic stenosis or occlusion of two or more mesenteric arteries. Multivessel revascularisation of both primary mesenteric vessels, the celiac artery and superior mesenteric artery (SMA), is the current mainstay of treatment; however, in a certain cohort of patients, revascularisation one or both vessels may not be possible. Arteries may be technically unreconstructable or the patient may be surgically unfit for the prolonged aortic cross clamping times required. Here we present a case involving a 72-year-old woman with acute on chronic mesenteric ischaemia. She was a high risk surgical patient with severe unreconstructable stenotic disease of the SMA and celiac arteries. She was successfully treated with single vessel revascularisation of the inferior mesenteric artery (IMA) via a common iliac to IMA reversed vein bypass. At two-year follow-up, the graft remains patent and the patient continues to be symptom-free and is maintaining her weight.

Venous drainage, a simple method to prevent the systemic consequences of ischaemia-reperfusion injury in acute lower limb ischaemia.

BACKGROUND: Ischaemia-reperfusion injury (I-R injury) is a recognised and potentially fatal complication following revascularisation of an ischaemic limb. Prevention of reperfusion injury is the focus of much research, but effective drug regimens have yet to be established into clinical practice. CASE REPORT: Here we present a man with prolonged, severe lower limb ischaemia, successfully treated with a novel surgical technique for preventing I-R injury. Prior to revascularisation, the common femoral vein was cannulated and the harmful venous effluent was drained. The patient made an excellent recovery, the limb was salvaged and no systemic complications were encountered.