Very urgent carotid endarterectomy confers increased procedural risk.

BACKGROUND AND PURPOSE: Current Swedish guidelines recommend that carotid endarterectomy should be performed within 14 days of a qualifying neurological event, but it is not clear if very urgent surgery after an event is associated with increased perioperative risk. The aim of this study was to determine how the time between the event and carotid endarterectomy affects the procedural risk of mortality and stroke. METHODS: We prospectively analyzed data on all patients who underwent carotid endarterectomies for symptomatic carotid stenosis between May 12, 2008, and May 31, 2011, with records in the Swedish Vascular Registry (Swedvasc). Patients were divided according to time between the qualifying event and surgery (0-2 days, 3-7 days, 8-14 days, 15-180 days). Stroke rate and mortality at 30 days postsurgery were determined. RESULTS: We analyzed data for 2596 patients and found that the combined mortality and stroke rate for patients treated 0 to 2 days after qualifying event was 11.5% (17 of 148) versus 3.6% (29 of 804), 4.0% (27 of 677), and 5.4% (52 of 967) for the groups treated at 3 to 7 days, 8 to 14 days, and 15 to 180 days, respectively. In a multivariate analysis, time was an independent risk factor for perioperative complications: patients treated at 0 to 2 days had a relative OR of 4.24 (CI, 2.07-8.70; P<0.001) compared with the reference 3- to 7-day group. CONCLUSIONS: In this study of patients treated for symptomatic carotid disease, it was safe to perform surgery as early as Day 3 after a qualifying neurological event in contrast to patients treated within 0 to 2 days, which has a significantly increased perioperative risk.

Differences in lesion severity and cellular composition between in vivo assessed upstream and downstream sides of human symptomatic carotid atherosclerotic plaques.

BACKGROUND: The heterogeneous structure of carotid atherosclerotic plaques may be better understood if it is related to blood flow variations, influencing gene expression and cellular functions. Upstream of the maximum stenosis there is laminar blood flow and high shear stress, downstream there is turbulence and low shear stress. We studied if these variations were associated with differences in plaque morphology and composition between sites located up- and downstream of the maximum stenosis in symptomatic carotid plaques. METHODS: Patients with symptomatic carotid stenosis were examined with magnetic resonance angiography to localize the maximum stenosis in-vivo, prior to endarterectomy. In 41 endarterectomized specimens, transverse tissue sections prepared up- and downstream of the maximum stenosis were compared using histopathology and immunohistochemistry. RESULTS: The location of maximum stenosis relative the carotid bifurcation varied considerably between plaques. Compared with the downstream side, the upstream side of the stenosis had higher incidence of severe lesions with cap rupture and intraplaque hemorrhage, more macrophages, less smooth muscle cells and more collagen. CONCLUSIONS: The up- and downstream sides of symptomatic carotid plaques differed in plaque morphology and composition. This implies that the intraplaque location of sampling sites may be a confounding factor in studies of atherosclerotic plaques.

Urokinase-type plasminogen activator receptor is associated with macrophages and plaque rupture in symptomatic carotid atherosclerosis.

There is a strong correlation between macrophage infiltration and plaque instability in recently symptomatic carotid atherosclerotic plaques, and it is hypothesised that mechanisms related to macrophages may be involved in plaque vulnerability and rupture. We previously found high expression of urokinase-type plasminogen activator receptor (UPAR) in human macrophages. The aim of this study was to investigate whether UPAR co-localises with macrophages in symptomatic carotid plaques, and whether UPAR expression is associated with plaque rupture. Real-time RT-PCR assays showed that UPAR expression levels were high in monocyte-derived macrophages and in carotid endarterectomies compared with a tissue panel. Serial transverse sections were prepared from carotid endarterectomies from 12 symptomatic patients, and analyzed with immunohistochemical staining for UPAR and for CD68-positive macrophages, and with histopathological assessment. UPAR co-localised with CD68-positive macrophages, with a high correlation (r=0.90, p<0.001) between immunostained areas in 12 carotid endarterectomies from symptomatic patients. High degrees of UPAR and CD68 staining were found in sections around the bifurcation level where rupture was most common, while low degrees of staining were found in sections of the common carotid artery end of the endarterectomy (p<0.05). Higher degrees of UPAR staining were observed in ruptured plaque sections compared with non-ruptured sections. In conclusion, UPAR was highly expressed in monocyte-derived macrophages and in symptomatic carotid plaques, UPAR co-localised with macrophages in carotid symptomatic plaques and UPAR was predominantly found in ruptured plaque segments. These findings support the hypothesis that UPAR is related to plaque rupture in symptomatic atherosclerotic lesions.

Outcome after leg bypass surgery for critical limb ischemia is poor in patients with diabetes: a population-based cohort study.

OBJECTIVE: Our aim was to assess the risk of major amputation or death after leg bypass surgery for critical limb ischemia in patients with diabetes versus those without. RESEARCH DESIGN AND METHODS: We did a population-based cohort study by linking nationwide databases in Sweden. We identified 1,840 patients in the Swedish Vascular Registry who had their first leg bypass procedure for critical lower-limb ischemia between 1 January 2001 and 31 December 2003-742 with and 1,098 without diabetes. Our primary end point was first major amputation of the limb on which bypass was done or death. Individuals were followed up until 31 December 2005 through the National Hospital Patient Registry and the Cause-of-Death Registry. RESULTS: Incidence of ipsilateral amputation or death was higher in patients with diabetes than in patients without (30.2 vs. 22 events/100 person-years; crude hazard ratio [HR] 1.32 [95% CI 1.17-1.50]). Similarly, individuals with diabetes had a shorter amputation-free survival period than individuals without (2.3 years, range 1.9-2.8 vs. 3.4 years, range 3.1-3.7). Adjustment for demographic characteristics, comorbidities, and risk factors for amputation or death did not substantially affect the risk (HR 1.46 [95% CI 1.26-1.69]). The effect was more pronounced in male (1.75 [1.47-2.08]) than in female (1.35 [1.11-1.64]) patients after adjustment for age. CONCLUSIONS: Diabetes is associated with lower amputation-free survival after leg bypass for critical limb ischemia. Patients with diabetes and limb ischemia need intensified treatment of diabetes-related risk factors to improve outcome.

Relationships between free radical levels during carotid endarterectomy and markers of arteriosclerotic disease.

BACKGROUND: Free radical production is elevated in jugular venous blood emerging from the brain in conjunction with carotid endarterectomy. This study explores the relationships between markers for lesion progression in arteriosclerosis, production of radicals and clinical characteristics. METHODS: The radical production during carotid endarterectomy was studied in 13 patients with an ex vivo spin trap method using OXANOH as a spin trap. MCP-1, ICAM-1, MMP-9 and oxLDL were determined in venous blood samples before, during and after clamping of the carotid artery. Principal component analysis (PCA) as well as partial least square regression analysis (PLS) was applied to interpret the data. RESULTS: PCA and PLS analysis revealed that high values of MMP-9 and low values of ICAM-1 were associated with high radical production whereas MCP-1 and oxLDL were not correlated to radical production. MMP-9 was elevated at diabetes, high haemoglobin, high leucocyte counts and thrombocyte counts as well as at contralateral stenosis, whereas ICAM-1 showed reversed relationships to these clinical variables. MCP-1 increased during surgery. CONCLUSIONS: The main finding in our study is that MMP-9 in plasma is asscociated with radical production during carotid endarterectomy, suggesting that this enzyme might be involved in the pathogenesis of brain damage in conjunction with ischaemia-reperfusion.

Should blunt arterial trauma to the extremities be treated with endovascular techniques?

Endovascular techniques are making progress in most aspects of vascular disease. Penetrating or blunt trauma to large arteries can in many cases be managed elegantly with endovascular techniques. However when it comes to arterial trauma of the extremities things are more complicated. There are no reports hitherto in the literature on endovascular treatment of blunt injuries to the arteries of the extremities. In the present report we describe two cases of blunt trauma to the brachial artery treated with balloon angioplasty (PTA) to fixate the dissected intima to the vessel wall. The "glueing" was effective in giving a long lasting patency.We anticipate that there may be a role, though limited, for using PTA as a means of "glueing" the intima. More advanced techniques such as insertion of stents or stent-grafts in traumatized extremity arteries would rarely be indicated.

Preserved pelvic circulation after stent-graft treatment of complex aortoiliac artery aneurysms: a new approach.

PURPOSE: To describe an endovascular technique that allows stent-graft treatment of aortoiliac aneurysmal disease affecting both common iliac arteries (CIA), with maintenance of pelvic circulation on one side. TECHNIQUE: For patients with aortoiliac aneurysms, both common femoral arteries (CFA) were surgically exposed. One internal iliac artery (IIA) was initially embolized with coils. A bifurcated stent-graft main body was deployed with the proximal end just below the renal arteries. On the ipsilateral side, the stent-graft limb was extended 3 cm beyond the orifice of the embolized IIA into the external iliac artery (EIA) using stent-graft limb extenders. On the contralateral side, the stent-graft limb was deployed so that the distal end was 10 to 15 mm proximal to the patent IIA orifice. Via a left brachial artery access, the IIA was catheterized, and stent-grafts were deployed from the distal end of the contralateral AAA stent-graft limb into the IIA. A femorofemoral crossover graft provided circulation to the leg ipsilateral to the IIA stent-graft, and the EIA on the same side was ligated. The technique can also be modified to treat isolated bilateral CIA aneurysms. CONCLUSIONS: By extending the distal aspect of the stent-graft into an IIA, bilateral CIA aneurysms can be excluded while preserving pelvic circulation on one side.

Effects of pretreatment with a xanthine oxidase inhibitor on free radical levels during carotid endarterectomy.

OBJECTIVE: Free radicals contribute to the tissue damage caused by ischaemia-reperfusion. The aim of the present study was to investigate whether preoperative antioxidant therapy (allopurinol) affects free radical levels in cerebral venous blood in connection with surgery for carotid artery stenosis. MATERIALS AND METHODS: Twenty-five patients were randomised into the study. Thirteen were controls and 12 were pretreated with allopurinol the day before surgery. Before, during and after surgery, blood samples were drawn from the ipsilateral jugular vein. Radical levels were measured using the spin trap technique ex vivo using OXANOH as the spin trap. Multivariate statistics were used with Principal Component Analysis and Partial Least Square regression analysis. RESULTS: Radical levels increased with diabetes, high leukocyte count, high creatinine and a high degree of contralateral stenosis. Radical levels decreased with high age, blood pressure, collateral circulation as well as operation for left-side carotid artery stenosis. After pretreatment with allopurinol, several of the relationships noted in the control group were eliminated, i.e. leukocyte count, side of operation, Betapred pretreatment and collateral circulation. CONCLUSIONS: Radical levels can be determined in connection with surgery for carotid artery stenosis using an ex vivo spin trap method. With preoperative antioxidant therapy the relationships between enhanced radical levels and clinical data, as seen in control subjects, disappeared. This might indicate a beneficial effect of preoperative pretreatment with antioxidants.