The incidence of spinal cord ischaemia following thoracic and thoracoabdominal aortic endovascular intervention.

OBJECTIVES: To determine the incidence and risk factors for spinal cord ischaemia (SCI) following thoracic and thoracoabdominal aortic intervention. METHODS: A prospective database of all thoracic and thoracoabdominal aortic interventions between 2001 and 2009 was used to investigate the incidence of SCI. All elective and emergency cases for all indications were included. Logistic regression was used to investigate which factors were associated with SCI. RESULTS: 235 patients underwent thoracic aortic stent grafting; 111(47%) thoracic aortic stent-grafts alone, with an additional 14(6%) branched or fenestrated thoracic grafts, 30(13%) arch hybrid procedures and 80(34%) visceral hybrid surgical and endovascular procedures. The global incidence of SCI for all procedures was 23/235 (9.8%) and this included emergency indications (ruptured TAAA and acute complex dissections) but the incidence varied considerably between types of procedures. Of the 23 cases, death occurred in 4 patients but recovery of function was seen in 6. Thus, permanent paraplegia occurred in 13/235 (5.5%) patients. Of the nine pre-specified factors investigated for association with SCI, only percentage of aortic coverage was significantly associated with the incidence of SCI; adjusted odds ratio per 10% increase in aorta covered=1.78[95% CI 1.18-2.71], p=0.007. The procedures in patients who developed SCI took longer (463.5 versus 307.2 minutes) and utilised more stents (4 versus 2). CONCLUSION: SCI following thoracic and thoracoabdominal aortic endovascular intervention is associated with the proportion of aorta covered. The degree of risk varies between different types of procedure and this should be carefully considered in both selection and consenting of patients.

The visceral hybrid repair of thoraco-abdominal aortic aneurysms--a collaborative approach.

OBJECTIVE: To report the collaborative data of 3 major European Vascular Units using the 'visceral hybrid' procedure for thoraco-abdominal aortic aneurysms and dissections. METHODS: A consecutive series of 107 urgent and elective high-risk patients were included in a prospectively collected database. RESULTS: All stents involved the entire thoracic and abdominal aorta with left subclavian coverage in 19 and revascularisation in 12. The distal landing zone was in the infra-renal aorta in 75% and in the iliac artery in 25%. The 30-day mortality rate was 16/107 (14.95%). 13/107 (12.1%) of the patients suffered spinal cord ischaemia which was complete and permanent in 9/12 (8.4%). 4 patients (3.7%) required long term dialysis and a segment of gut infarction requiring resection occurred in 3 (2.8%). Most patients had visceral bypass grafting and aortic stent-grafting performed in one stage. In 18 patients the stenting was performed later. Three of these patients ruptured before the stenting procedure was undertaken. CONCLUSION: These early results of visceral hybrid repair for high-risk patients with complex thoraco-abdominal aortic aneurysms are encouraging, in a group of patients in whom fenestrated/branched stent-grafting is not an option and open surgery hazardous.

Effect of venous ulcer exudates on angiogenesis in vitro.

BACKGROUND: Angiogenesis, the formation of new from existing capillaries, is an important mechanism in venous ulcer healing. The aim of this study was to determine whether venous leg ulcer wound exudates stimulate or inhibit angiogenesis. METHODS: Fluid exudate was obtained from 16 venous ulcers over a 4-h interval. Five of the ulcers had not healed after more than 1 year of compression bandaging, and five were rapidly healing ulcers. As a control, acute wound fluids were collected from subcutaneous drains in seven patients. Vascular endothelial growth factor (VEGF) at 2 ng/ml acted as a positive control. Tubules stained with an antiendothelial antibody were quantified using an image analysis system. The extent of angiogenesis was expressed as the ratio of the mean tubule length in the test wells over that in blank control wells. RESULTS: Venous ulcer exudates significantly inhibited angiogenesis (mean (95 per cent confidence interval) 0.72 (0.48 to 0.96)) compared with acute wound fluids (2.48 (0.86 to 4.10)) (P < 0.002) and VEGF (1.47 (1.32 to 1.61)) (P = 0.01). Exudates from the five non-healing venous ulcers inhibited angiogenesis (0.31 (0.15 to 0.46)) significantly more than exudates from the five rapidly healing venous ulcers (0.93 (0.21 to 1.65)) (P = 0.03). CONCLUSION: Fluid exudate from venous ulcers, in particular those that healed slowly, inhibited experimental angiogenesis in this study.

What can wound fluids tell us about the venous ulcer microenvironment?

Research into the healing of venous leg ulcers is increasing as they are a common problem. The wound fluid bathing an ulcer is thought to reflect the wound microenvironment, and the properties of wound fluids have been studied in attempts to find ways to promote healing. After a brief summary of normal wound healing, this article reviews some of the research that has been carried out on venous ulcer wound fluid, with respect to its biochemistry, proteolytic nature, growth factor profile, and effects on cell cultures. Some of the problems and pitfalls inherent in performing and interpreting wound fluid studies are discussed. Finally, a proposal is made for standardizing research on wound fluids that would improve comparisons between different studies.