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Background: The purpose of this study was to determine the cerebrovascular risk stratification potential of baseline degree of stenosis, clinical features, and ultrasonic plaque characteristics in patients with asymptomatic internal carotid artery (ICA) stenosis. Methods: This was a prospective, multicenter, cohort study of patients undergoing medical intervention for vascular disease. Hazard ratios for ICA stenosis, clinical features, and plaque texture features associated with ipsilateral cerebrovascular or retinal ischemic (CORI) events were calculated using proportional hazards models. Results: A total of 1121 patients with 50% to 99% asymptomatic ICA stenosis in relation to the bulb (European Carotid Surgery Trial [ECST] method) were followed-up for 6 to 96 months (mean, 48). A total of 130 ipsilateral CORI events occurred. Severity of stenosis, age, systolic blood pressure, increased serum creatinine, smoking history of more than 10 pack-years, history of contralateral transient ischemic attacks (TIAs) or stroke, low grayscale median (GSM), increased plaque area, plaque types 1, 2, and 3, and the presence of discrete white areas (DWAs) without acoustic shadowing were associated with increased risk. Receiver operating characteristic (ROC) curves were constructed for predicted risk versus observed CORI events as a measure of model validity. The areas under the ROC curves for a model of stenosis alone, a model of stenosis combined with clinical features and a model of stenosis combined with clinical, and plaque features were 0.59 (95% confidence interval [CI] 0.54-0.64), 0.66 (0.62-0.72), and 0.82 (0.78-0.86), respectively. In the last model, stenosis, history of contralateral TIAs or stroke, GSM, plaque area, and DWAs were independent predictors of ipsilateral CORI events. Combinations of these could stratify patients into different levels of risk for ipsilateral CORI and stroke, with predicted risk close to observed risk. Of the 923 patients with

OBJECTIVE: To determine baseline clinical and ultrasonographic plaque factors predictive of progression or regression of asymptomatic carotid stenosis and the predictive value of changes in stenosis severity on risk of first ipsilateral cerebral or retinal ischemic events (including stroke).METHODS: A total of 1121 patients with asymptomatic carotid stenosis of 50% to 99% in relation to the bulb diameter (European Carotid Surgery Trial [ECST] method) underwent six monthly clinical assessments and carotid duplexes for up to 8 years (mean follow-up, 4 years). Progression or regression was considered present if there was a change of at least one grade higher or lower, respectively, persisting for at least two consecutive examinations.RESULTS: Regression occurred in 43 (3.8%), no change in 856 (76.4%), and progression in 222 (19.8%) patients. Younger age, high grades of stenosis, absence of discrete white areas in the plaque, and taking lipid lowering therapy were independent baseline predictors of increased incidence of regression. High serum creatinine, male gender, not taking lipid lowering therapy, low grades of stenosis, and increased plaque area were independent baseline predictors of progression. One hundred and thirty first ipsilateral cerebral or retinal ischemic events, including 59 strokes, occurred. Forty (67.8%) of the strokes occurred in patients whose stenosis was unchanged, 19 (32.2%) in those with progression, and zero in those with regression. For the entire cohort, the 8-year cumulative ipsilateral cerebral ischemic stroke rate was zero in patients with regression, 9% if the stenosis was unchanged, and 16% if there was progression (average annual stroke rates of 0%, 1.1%, and 2.0%, respectively; log-rank, P = .05; relative risk in patients with progression, 1.92; 95% confidence interval, 1.14-3.25). For patients with baseline stenosis 70% to 99% in relation to the distal internal carotid (North American Symptomatic Carotid Endarterectomy Trial [NASCET] method), in the absence of progression (n = 349), the 8-year cumulative ipsilateral cerebral ischemic stroke rate was 12%. In the presence of progression (n = 77), it was 21% (average annual stroke rates of 1.5% and 2.6%, respectively; log-rank, P = .34). Only nine (30%) of the 30 strokes occurred in the progression group.CONCLUSIONS: Progressive asymptomatic carotid stenosis identified a subgroup with about twice the risk of ipsilateral stroke compared with those without progression. However, the clinical value of screening for progression simply for selecting patients for carotid procedures is limited because of the low frequency of progression and its relatively low associated stroke rate. The cost effectiveness of screening for change in stenosis severity to better direct current optimal medical treatment needs testing.

OBJECTIVE: To test the hypothesis that the size of a juxtaluminal black (hypoechoic) area (JBA) in ultrasound images of asymptomatic carotid artery plaques predicts future ipsilateral ischemic stroke. METHODS: A JBA was defined as an area of pixels with a grayscale value 10 mm(2) (P < .001). In a Cox model with ipsilateral ischemic events (amaurosis fugax, transient ischemic attack [TIA], or stroke) as the dependent variable, the JBA (8 mm(2)) was still significant after adjusting for other plaque features known to be associated with increased risk, including stenosis, grayscale median, presence of discrete white areas without acoustic shadowing indicating neovascularization, plaque area, and history of contralateral TIA or stroke. Plaque area and grayscale median were not significant. Using the significant variables (stenosis, discrete white areas without acoustic shadowing, JBA, and history of contralateral TIA or stroke), this model predicted the annual risk of stroke for each patient (range, 0.1%-10.0%). The average annual stroke risk was

The coexistense of an abdominal aortic aneurysm with ectopic main renal vasculature complicates aortic surgery and mandates a focused imaging evaluation and a carefully planned operation to minimize renal ischemia. We present the case of a 75-year-old man with an abdominal aortic aneurysm and a right kidney with two ectopic main renal arteries, one originating from the aneurysmal distal aorta and the other from the right common iliac artery; the patient underwent a surgical repair and followed an uneventful course with no deterioration of renal function. The preoperative and intraoperative details are reported, along with a review of the literature. © 2007 Sage Publications.

Ischemic preconditioning (IPC) and intermittent vascular control (IVC) have been shown to reduce the number of ischemia/reperfusion injuries during liver resections with the Pringle maneuver. Our study aimed to compare the beneficial effect of these two modalities in relation to the duration of normothermic liver ischemia. A group of 24 Landrace pigs with a mean body weight of 25 to 30 kg were subjected to extended liver resection of more than 65%. Although, 12 animals underwent IPC (10 minutes of ischemia and 10 minutes of reperfusion), and subsequently the Pringle maneuver was applied for 90 minutes (n= 6) or 120 minutes (n= 6). Another 12 animals underwent liver resection by IVC (20 minutes of ischemia alternated with 5 minutes of reperfusion) for 60 minutes (n = 6) or 120 minutes (n = 6) of inflow vascular control. At 90 minutes of liver ischemia, the IPC group demonstrated lower levels of asportate aminotransferase (AST) (173 +/- 53 vs. 265 +/- 106 IU; p =0.089) and malondialdehyde (NIDA) (2.60 +/- 1.03 vs. 5.33 +/- 2.25 mu mol/L; p =0.022) and higher liver tissue cAMP (200 +/- 42 vs. 146 +/- 40 pmol/g wet wt, p = 0.04) compared to the IVC group. However, no pathologic differences were observed between the two groups. By contrast, at 120 minutes of liver ischemia, IVC proved to be more beneficial, reflected by lower levels of AST (448 +/- 135 vs. 857 +/- 268 IU; p = 0.006) and MDA (8.33 +/- 1.75 vs. 12.7 +/- 4.31 mu mol/L; (p = 0.045), a higher cAMP level (127 +/- 10 vs. 97 31 pmol/g wet wt p = 0.045), and eventually less cellular necrosis (necrosis score 1.66 +/- 0.51 vs. 2.85 +/- 1.16; p = 0.04) compared to the IPC group. It appears that IPC should be employed when liver ischemia is anticipated to last less than 90 minutes, followed by IVC when the liver ischemia is expected to last 120 minutes.

Objective: to present our experience with stent placement in renal arteries in solitary kidneys for treating renal insufficiency Design: retrospective analysis. Materials: in 26 patients With solitary kidney (17 men, 9 women, Mean age: 63 years), presented with renal insufficiency (se-creat >0.144 mmol/l), stent was placed in a stenosed renal artery. We analysed the clinical outcome, based on the level of creatinine at 3 months following the procedure. Clinical benefit was considered when there was a decrease compared to the baseline creatinine by >20% or a stabilisation of the creatinine value (+/-20% of the baseline). Results: in 16 of the 26 patients (62%), clinical benefit Teas achieved. However, 38% of the study population, renal function continued to deteriorate. Baseline creatinine value was the single best predictor for clinical benefit achievement (odds ratio: 13; 95% confidence intervals: 1.6-107, p=0.01). Conclusion: renal stenting results in improvement or stabilisation of renal function in the majority of the patients with solitary kidneys and renal artery stenosis, presenting with renal insufficiency. Because best outcome was observed mainly in those patients with not progressed renal insufficiency, intervention should be focused oil that group.

Endovascular repair of abdominal aortic aneurysms (AAA) is an alternative to conventional surgical aortic reconstruction. However the presence of renal artery stenosis (RAS) and/or accessory renal arteries may alter the endovascular approach in these cases. We present two cases with infrarenal aneurysms and a coexisting unilateral renal artery stenosis (first case) and accessory renal artery (second case). In both patients endovascular treatment was undertaken. In the first patient a stent was placed for the RAS and an aortic endograft with suprarenal fixation for the aneurysm. In the second patient the placement of an aortic endograft with suprarenal fixation occluded the accessory renal artery. In the first patient renal function was normal pre- and post-intervention. In the second patient, renal function was normal pre-intervention but showed a slight deterioration postoperatively, returning to normal after 10 days. Both patients were normotensive pre- and post-intervention. In conclusion, RAS and AAA may be treated by the placement of a stent and a stent-graft simultaneously. During endovascular repair of AAA, a significant accessory renal artery (around 3 mm in diameter) may safely be excluded in patients with otherwise normal renal function. © 2003 Elsevier Science Ltd. All rights reserved.

An association between symptomatic carotid stenosis and recent infection with Chlamydia pneumoniae is reported. Thirty-five patients (20 symptomatic and 15 asymptomatic) with carotid stenosis of 70% to 90% underwent carotid endarterectomy. Endarterectomy was performed without patch and shunt; the average occlusion time of the internal carotid artery was 14 +/- 3 min. The atheromatic plaque and a portion of the thyroid artery were examined with polymerase chain reaction and peripheral vein blood was obtained for serologic detection of systematic infection, and IgG and IgM antibodies to C. pneumoniae by enzyme-linked immunosorbent assay. Twenty of 35 patients (57.1%) had increased titers of IgG antibodies to C pneumoniae. Eight patients revealed IgG plus IgM antibodies; two of the eight had IgG, IgM, and positive findings on polymerase chain reaction. No C pneumoniae was detected on the thyroid arteries. Sixty-five percent (13/20) of the patients with increased IgG antibodies to C pneumoniae, 87.5% (7/8) with IgG + IgM, and 100% with IgG + IgM + positive polymerase chain reaction were symptomatic. Plaque morphology in association with symptoms did not reveal a significant correlation between soft plaques and symptoms, whereas the majority of the symptomatic patients had plaques of type III-V. Patients having recent contamination and positive polymerase chain reaction had a significant relationship between C pneumoniae infection and symptomatic carotid disease. This supports the hypothesis that C pneumoniae infection can produce a kind of instability of the carotid plaque. The results of this study demonstrate that patients with advanced atherosclerotic carotid disease have an increased incidence of C pneumoniae infection. Recent infection could be responsible for instability of the carotid plaque, causing cerebral ischemic episodes.

The authors investigated 125 patients suffering from primary Raynaud’s phenomenon by the following laboratory hematologic parameters: (1) cryofibrinogen and cryoglobulins; (2) serum albumins and immunoglobulins IgG, IgA, and IgM, as well as complement factors C3 and C4; (3) clotting inhibitors, antithrombin III, protein C and protein S, as well as alpha(1) antitrypsin. Results were as follows: 77 (62%) patients had cryofibrinogen in their blood plasma, 50 (40%) patients had precipitation of cryoglobulins, and 65 (52%) patients had an increase of alpha(2) globulin in the serum electrophoresis. Of the immunoglobulins, IgM was found increased in 42 patients (34%). Of the clotting time inhibitors, antithrombin III CAT III) had a lower activity in 50 (40%) patients as compared with that of normal subjects. Protein C, protein S, and alpha(1) antitrypsin levels were lower in 21 (16.8%), 13 (10.4%), and 10 (8%) of patients, respectively. Statistical analysis of the results showed that all the protein fractions except for gamma-globulin presented a statistically significant difference as compared with those of the controls (P < 0.0001). Immunoglobulins IgG and IgA of the patients were significantly lower than those of the normal controls (P < 0.001). The C3 and C4 factors of the complement presented statistically significant lower values (P < 0.001 and P < 0.0001 respectively). Finally, AT III appeared in lower values than those of the normal controls, being statistically significant (P < 0.0001). These results suggest that patients with primary Raynaud’s phenomenon present changes in the levels of certain hematologic parameters, a fact that is probably connected with etiology. Thus further study and assessment might contribute to the diagnosis, discovery of the subjective systemic etiology, and better therapeutic management of Raynaud’s phenomenon.

41 dogs were subjected to percutaneous arterial embolization of branches or the main trunk of the renal artery with or without prior injury to the kidney. 8 materials were used: homologous blood clot, muscle, fat, fascia, barium sulfate, plain catgut, gelfoam and polyvinyl alcohol (Ivalon). From the angiographic investigation over a relatively long period, it was observed that complete recanalization of the embolized vessels occurred only with blood clot and gelfoam; partial recanalization, with muscle fat and plain catgut; and no recanalization at all with fat, barium sulfate and Ivalon.