17 research outputs found
Asymptomatic internal carotid artery stenosis and cerebrovascular risk stratification
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 <70% stenosis, the predicted cumulative 5-year stroke rate was <5% in 495, 5% to 9.9% in 202, 10% to 19.9% in 142, and <20% in 84 patients. Conclusion Cerebrovascular risk stratification is possible using a combination of clinical and ultrasonic plaque features. These findings need to be validated in additional prospective studies of patients receiving optimal medical intervention alone. Copyright © 2010 by the Society for Vascular Surgery
The size of juxtaluminal hypoechoic area in ultrasound images of asymptomatic carotid plaques predicts the occurrence of stroke
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 <25 adjacent to the lumen without a visible echogenic cap after image normalization. The size of a JBA was measured in the carotid plaque images of 1121 patients with asymptomatic carotid stenosis 50% to 99% in relation to the bulb (Asymptomatic Carotid Stenosis and Risk of Stroke study); the patients were followed for up to 8 years. Results: The JBA had a linear association with future stroke rate. The area under the receiver-operating characteristic curve was 0.816. Using Kaplan-Meier curves, the mean annual stroke rate was 0.4% in 706 patients with a JBA <4 mm 2, 1.4% in 171 patients with a JBA 4 to 8 mm2, 3.2% in 46 patients with a JBA 8 to 10 mm2, and 5% in 198 patients with a JBA >10 mm2 (P <.001). In a Cox model with ipsilateral ischemic events (amaurosis fugax, transient ischemic attack [TIA], or stroke) as the dependent variable, the JBA (<4 mm2, 4-8 mm2, >8 mm2) 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 <1% in 734 patients, 1% to 1.9% in 94 patients, 2% to 3.9% in 134 patients, 4% to 5.9% in 125 patients, and 6% to 10% in 34 patients. Conclusions: The size of a JBA is linearly related to the risk of stroke and can be used in risk stratification models. These findings need to be confirmed in future prospective studies or in the medical arm of randomized controlled studies in the presence of optimal medical therapy. In the meantime, the JBA may be used to select asymptomatic patients at high stroke risk for carotid endarterectomy and spare patients at low risk from an unnecessary operation
Templates Implementation for Structured DICOM Diagnosis Reporting in
We previously reported the development of a DICOM structured diagnosis application allowing efficient storage and retrieval of echocardiographic information. Reports are generated for every patient and every type of information is stored into a complex database. For such a structure to be efficiently use in the echocardiography laboratory, we extended EchoSection template with a description section including a EchoDescription template allowing generation of echocardiographic reports for every cardiac structure. This was possible by using parameters and by developing a simple programming language for specifying complex relationships between different rows of the template. We are currently generating reports for a large variety of cardiac diseases and storing them into a DICOM image database. 1
CERTAIN TYPICAL ASPECTS OF CENTROGENIC ARRHYTHMIAS INDUCED BY CHEMICAL-STIMULATION OF CEREBRAL STRUCTURES IN RATS
Prevention of serious vascular events by aspirin amongst patients with peripheral arterial disease: randomized, double-blind trial
Objective. To assess the prophylactic efficacy of aspirin and a high-dose antioxidant vitamin combination in patients with peripheral arterial disease (PAD) in terms of reduction of the risk of a first vascular event (myocardial infarction, stroke, vascular death) and critical limb ischaemia
Perspectives: Rationale and design of the ISACS-TC (International Survey of Acute Coronary Syndromes in Transitional Countries) project
During the past 10 years, the health of people in Eastern Europe and the former Soviet Union has undergone changes very different from the health patterns seen in their Western counterparts. Mortality from cardiovascular disease has been decreasing continuously in the USA and many Western European countries, but it has increased or remained unchanged in many of the states of Eastern Europe. Analysis of this phenomenon has been hindered by insufficient information. The International Registry of Acute Coronary Syndromes registry study in Transitional Countries (ISACS-TC) is both a retrospective - over a 1-year period - and prospective study which was designed in order to obtain data of patients with acute coronary syndromes (ACSs) in countries with economy in transition in Central and Eastern Europe, and herewith control and optimize internationally guideline recommended therapies in these countries. Adhesion to the project was given by 112 Collaborating Centres in 17 countries with economy in transition (Albania, Bosnia and Herzegovina, Belarius, Bulgaria, Croatia, Hungary, Kosovo, Latvia, Lithuania, Macedonia, Moldova, Montenegro, Romania, Russian Federation, Serbia, Slovakia, Slovenia, and Ukraine). A total of 47 cluster sites in 11 countries in Central and Eastern Europe are currently collaborating in ISACS-TC. The registry encourages optimal individualization of evidence-based therapies and the international patient body ensures good representation of multiple practice patterns. It may help to make an additional improvement in clinical outcomes of countries with economy in transition