Carotid Ultrasound Images Research Articles

A “Twisting and Bending” Model-Based Nonrigid Image Registration Technique for 3-D Ultrasound Carotid Images

Atherosclerosis at the carotid bifurcation resulting in cerebral emboli is a major cause of ischemic stroke. Most strokes associated with carotid atherosclerosis can be prevented by lifestyle/dietary changes and pharmacological treatments if identified early by monitoring carotid plaque changes. Registration of 3-D ultrasound (US) images of carotid plaque obtained at different time points is essential for sensitive monitoring of plaque changes in volume and surface morphology. This registration technique should be nonrigid, since different head positions during image acquisition sessions cause relative bending and torsion in the neck, producing nonlinear deformations between the images. We modeled the movement of the neck using a "twisting and bending" model with only six parameters for nonrigid registration. We evaluated the algorithm using 3-D US carotid images acquired at two different head positions to simulate images acquired at different times. We calculated the mean registration error (MRE) between the segmented vessel surfaces in the target image and the registered image using a distance-based error metric after applying our "twisting and bending" model-based nonrigid registration algorithm. We achieved an average registration error of 0.80 +/-0.26 mm using our nonrigid registration technique, which was a significant improvement in registration accuracy over rigid registration, even with reduced degrees-of-freedom compared to the other nonrigid registration algorithms.

Contrast-Enhanced Ultrasound Imaging of Intraplaque Neovascularization in Carotid Arteries: Correlation With Histology and Plaque Echogenicity

This study was designed to evaluate contrast-enhanced ultrasound imaging of carotid atherosclerosis as a clinical tool to study intraplaque neovascularization. Plaque neovascularization is associated with plaque vulnerability and symptomatic disease; therefore, imaging of neovascularization in carotid atherosclerosis may represent a useful tool for clinical risk stratification and monitoring the efficacy of antiatherosclerotic therapies. Thirty-two patients with 52 carotid plaques were studied by standard and contrast-enhanced ultrasound imaging. In 17 of these patients who underwent endarterectomy, the surgical specimen was available for histological determination of microvessel density by CD31/CD34 double staining. Plaque echogenicity and degree of stenosis at standard ultrasound imaging were evaluated for each lesion. Contrast-agent enhancement within the plaque was categorized as absent/peripheral (grade 1) and extensive/internal (grade 2). In the surgical subgroup, plaques with higher contrast-agent enhancement showed a greater neovascularization at histology (grade 2 vs. grade 1 contrast-agent enhancement: median vasa vasorum density: 3.24/mm(2) vs. 1.82/mm(2), respectively, p = 0.005). In the whole series of 52 lesions, echolucent plaques showed a higher degree of contrast-agent enhancement (p < 0.001). Stenosis degree was not associated with neovascularization at histology or with the grade of contrast-agent enhancement. Carotid plaque contrast-agent enhancement with sonographic agents correlates with histological density of neovessels and is associated with plaque echolucency, a well-accepted marker of high risk lesions, but it is unrelated to the degree of stenosis. Contrast-enhanced carotid ultrasound imaging may provide valuable information for plaque risk stratification and for assessing the response to antiatherosclerotic therapies, beyond that provided by standard ultrasound imaging.

TH‐C‐342‐03: Quantitative Medical Image Analysis for Early Detection, Diagnosis, Outcome Prediction, and Treatment

Medical imaging and image analysis has revolutionized the patient care as well as many research activities in biology and healthcare. Stet‐of‐the‐art methods and approaches for medical image segmentation, quantitative analysis, and their use for computer‐aided diagnosis and disease progression prediction will be the main target of this presentation. Special focus will be given to several high‐complexity projects in the areas of coronary image analysis via fusion of intravascular ultrasound and angiography, coronary plaque analysis, plaque progression prediction, cardiovascular risk factor assessment via analysis of carotid and brachial ultrasound images, pulmonary CT image analysis, computer‐aided diagnosis of congenital aortic disease, cartilage MR image analysis, and liver surgery planning. The talk will be accompanied by live demonstrations of the software tools developed for the above‐referenced purposes.

Development of 3D ultrasound techniques for carotid artery disease assessment and monitoring

Quantitative measurements of carotid plaque burden are used to monitor patients and evaluate established interventions as well as new treatment options. Three-dimensional ultrasound (3D US) techniques were developed to noninvasively monitor the progression of carotid artery disease in both symptomatic and asymptomatic patients. Three-dimensional carotid US images were acquired and reconstructed, and methods for quantitative assessment were developed. The measurement of intima-media thickness (IMT) based on two-dimensional ultrasound (2D US) images was extended to a 3D vessel-wall-plus- plaque thickness (VWT), obtained by computing the distance between the carotid wall and lumen surfaces on a point-by-point basis. VWT measurements were superimposed on the arterial wall to produce 3D VWT maps. VWT changes were determined by comparing the 3D VWT maps obtained at two different time points. To facilitate the visualization and interpretation of the VWT and VWT-Change maps, a technique to flatten these maps was developed. Carotid remodeling involving changes in both arterial wall and plaque thickness was assessed with VWT maps obtained from in vivo 3D ultrasound images. 3D carotid ultrasound image evaluation with VWT mapping provides a feasible means for the analysis of plaque burden volumes and changes.

Contrast-enhanced ultrasound imaging of atherosclerotic carotid plaque neovascularization: a new surrogate marker of atherosclerosis?

An atherosclerotic plaque requires a nutrient blood supply, which is predominantly derived from arterial vasa vasorum. A variety of factors (environmental and genetic) contribute to the initiation and growth of atherosclerosis within vessel walls. Chemotactic factors, such as tissue ischemic and hypoxic factors, stimulate the release of vascular endothelial growth factor (VEGF) proteins, resulting in vessel wall angiogenesis. These developments often precede the formation of the luminal plaque. In this report, we describe the use of contrast-enhanced carotid ultrasound (CECU) imaging for the detection and quantification of intra-plaque neovascularization. The efficacy of CECU was measured against the neovascular density observed within the tissue specimens obtained at the time of carotid endarterectomy surgery. The objective of this study was to provide a histologic correlation between CECU and carotid artery atherosclerotic plaque neovascularization. Fifteen patients with significant atherosclerotic carotid artery disease received a CECU examination prior to undergoing a carotid endarterectomy (CEA). Two patients received bilateral endarterectomies, resulting in a total of 17 cases. At the time of surgery, carotid plaque samples were surgically removed and stained with specific vascular markers (CD31, CD34, von Willebrand factor, and hemosiderin) designed to identify the presence and degree of neovascularization. The intra-plaque neovascularization recorded on preoperative CECU was correlated with the degree of neovascularization noted in the tissue specimens. The CECU neovascularization was correlated to CD31-stained tissue specimens. This correlation value was 0.68 using Spearman's rank method. When CECU results were correlated with the other histologic markers (CD34, von Willebrand factor, and hemosiderin), a correlation of 0.50 was obtained. In conclusion, contrast-enhanced carotid ultrasound correlated to the presence and degree of intra-plaque neovascularization as determined from histology specimens.

Distribution and Predictors of Carotid Intima‐Media Thickness in Young Adults

The authors' aim was to determine reference values and predictors for carotid intima-media thickness (CIMT) in the Bogalusa Heart Study. Carotid ultrasound images from 1203 young adults (mean age 36 years; 30% black, 43% male) were reviewed. Age-, sex-, and race-specific CIMT percentiles were estimated using multivariable regression. Nomograms of CIMT quartiles for persons aged 25 to 40 years are provided in 5-year increments. CIMT was thickest in the carotid bulb and increased linearly with age, most rapidly in the bulb. With age, composite CIMT increased most slowly in white women and more rapidly in white men and black women. Systolic blood pressure (P<.001) was the strongest predictor of composite CIMT. Male sex, total to high-density lipoprotein cholesterol ratio, and age independently predicted CIMT in all segments. This report may be used to help plan epidemiologic investigations and clinical trials investigating atherosclerosis and its changes with interventions.

Detection of Carotid Adventitial Vasa Vasorum and Plaque Vascularization With Ultrasound Cadence Contrast Pulse Sequencing Technique and Echo-Contrast Agent

Adventitial vasa vasorum and plaque vascularization have been established as predictors of unstable atheromasic lesions in cerebro- and cardiovascular patients. Ultrasound contrast agents provide reliable information on tissue perfusion and microcirculation. We used contrast ultrasound duplex scanning to identify carotid plaque vascularization. Contrast carotid duplex scanning was performed in 23 patients with plaques of different degree of stenosis and echogenicity. Plaque vascularization was detected in the fibrous and fibro-fatty tissue and not observed in the calcific nor in the necrotic and hemorrhagic tissue. Constantly, a small vessel was observed under ulcerations. Carotid contrast ultrasound imaging appears to be an emerging technique for identifying plaque angiogenesis. Further studies are needed to clarify the role of plaque angiogenesis for assessing cerebrovascular risk and to monitor effects of therapies aimed to plaque remodelling.

Torcetrapib and carotid intima-media thickness in mixed dyslipidaemia (RADIANCE 2 study): a randomised, double-blind trial

Patients with mixed dyslipidaemia have raised triglycerides, low high-density lipoprotein (HDL) cholesterol, and high low-density lipoprotein (LDL) cholesterol. Augmentation of HDL cholesterol by inhibition of the cholesteryl ester transfer protein (CETP) could benefit these patients. We aimed to investigate the effect of the CETP inhibitor, torcetrapib, on carotid atherosclerosis progression in patients with mixed dyslipidaemia. We did a randomised double-blind trial at 64 centres in North America and Europe. 752 eligible participants completed an atorvastatin-only run-in period for dose titration, after which they all continued to receive atorvastatin at the titrated dose. 377 of these patients were randomly assigned to receive 60 mg of torcetrapib per day and 375 to placebo. We made carotid ultrasound images at baseline and at 6-month intervals for 24 months. The primary endpoint was the yearly rate of change in the maximum intima-media thickness of 12 carotid segments. Analysis was restricted to 683 patients who had at least one dose of treatment and had at least one follow-up carotid intima-media measurement; they were analysed as randomised. Mean follow-up for these patients was 22 (SD 4.8) months. This trial is registered with ClinicalTrials.gov, number NCT00134238. The change in maximum carotid intima-media thickness was 0.025 (SD 0.005) mm per year in patients given torcetrapib with atorvastatin and 0.030 (0.005) mm per year in those given atorvastatin alone (difference -0.005 mm per year, 95% CI -0.018 to 0.008, p=0.46). Patients in the combined-treatment group had a 63.4% relative increase in HDL cholesterol (p<0.0001) and an 17.7% relative decrease in LDL cholesterol (p<0.0001), compared with controls. Systolic blood pressure increased by 6.6 mm Hg in the combined-treatment group and 1.5 mm Hg in the atorvastatin-only group (difference 5.4 mm Hg, 95% CI 4.3-6.4, p<0.0001). Although torcetrapib substantially raised HDL cholesterol and lowered LDL cholesterol, it also increased systolic blood pressure, and did not affect the yearly rate of change in the maximum intima-media thickness of 12 carotid segments. Torcetrapib showed no clinical benefit in this or other studies, and will not be developed further.

Carotid Ultrasound Imaging: An Effective Technique for Detecting Early Atherosclerosis–Vascular Screening for Cardiovascular Disease has Come of Age

“As the physicians say it happens in hectic fever, that in the beginning of the malady it is easy to cure but difficult to detect, but in the course of time, not having been either detected or treated in the beginning, it becomes easy to detect but difficult to cure.” Niccolo Machiavelli (1469-1527). The unfolding epidemic of cardiovascular (CV) disease (CVD) attracts an increasing sense of urgency as it fulfills the World Health Organization’s projection of becoming the leading cause of morbidity and mortality worldwide. This urgency is compounded by the observation that stable angina is the presenting symptom for coronary heart disease (CHD) in only 25% of men and 47% of women; in the United States the majority of patients present with either a myocardial infarction or sudden cardiac

Carotid Artery Disease

Carotid arteries are the blood vessels that deliver blood through the neck to the brain. There is one carotid artery on each side of the neck, where its pulsation can be felt with a finger below the jaw bone. Blockages in the carotid artery decrease blood flow to the brain, causing a medical condition known as carotid artery disease. Interruptions in blood flow to the brain (commonly known as stroke) can cause permanent injury. This Cardiology Patient Page describes how blockages resulting from carotid artery disease cause stroke and what you and your doctor can do to prevent it. Stroke, or cerebrovascular accident, is most frequently caused by a sudden stoppage of blood flow to a portion of the brain. Every year in the United States, an estimated 750 000 people become victims of stroke. There are 2 common causes of stroke. First, an irregular heart rhythm, called atrial fibrillation, can cause stroke when small blood clots form as the heart is quivering instead of beating normally. Once a small blood clot is formed, it can be launched by the heart through the carotid arteries, block a blood vessel in the brain, and deprive that part of the brain of blood, resulting in a stroke. The other common cause of stroke is a blockage in the carotid arteries. The carotid arteries carry blood to the brain; like the blood vessels that supply blood to the heart, these arteries can become narrowed or blocked. The blockages are deposits of cholesterol, or atherosclerosis, that narrow the blood flow channel in the carotid arteries (Figure 1). If these cholesterol deposits or blockages break or rupture, small blood clots and cholesterol fragments break off from the plaque, enter the blood flow to the brain, and can get caught in a smaller blood vessel in …

Comparative evaluation of despeckle filtering in ultrasound imaging of the carotid artery

It is well-known that speckle is a multiplicative noise that degrades the visual evaluation in ultrasound imaging. The recent advancements in ultrasound instrumentation and portable ultrasound devices necessitate the need of more robust despeckling techniques for enhanced ultrasound medical imaging for both routine clinical practice and teleconsultation. The objective of this work was to carry out a comparative evaluation of despeckle filtering based on texture analysis, image quality evaluation metrics, and visual evaluation by medical experts in the assessment of 440 (220 asymptomatic and 220 symptomatic) ultrasound images of the carotid artery bifurcation. In this paper a total of 10 despeckle filters were evaluated based on local statistics, median filtering, pixel homogeneity, geometric filtering, homomorphic filtering, anisotropic diffusion, nonlinear coherence diffusion, and wavelet filtering. The results of this study suggest that the first order statistics filter lsmv, gave the best performance, followed by the geometric filter gf4d, and the homogeneous mask area filter lsminsc. These filters improved the class separation between the asymptomatic and the symptomatic classes based on the statistics of the extracted texture features, gave only a marginal improvement in the classification success rate, and improved the visual assessment carried out by the two experts. More specifically, filters lsmv or gf4d can be used for despeckling asymptomatic images in which the expert is interested mainly in the plaque composition and texture analysis; and filters lsmv, gf4d, or lsminsc can be used for the despeckling of symptomatic images in which the expert is interested in identifying the degree of stenosis and the plaque borders. The proper selection of a despeckle filter is very important in the enhancement of ultrasonic imaging of the carotid artery. Further work is needed to evaluate at a larger scale and in clinical practice the performance of the proposed despeckle filters in the automated segmentation, texture analysis, and classification of carotid ultrasound imaging.

Presentation of a Non-invasive Method of Estimating Arterial Stiffness by Modeling Blood Flow and Arterial Wall Based on the Determination of Elastic Module of Arterial Wall

Introduction: Arterial stiffness is an important predictor of cardiovascular risk. Several indices have been introduced to estimate the arterial stiffness based on the changes in the brachial blood pressure. Since the substitution of the blood pressure changes in the central arteries such as carotid with the blood pressure changes in the brachial results in error in the blood flow, it is of importance to present an elastic parameter based on the mechanical models without any reliance on the brachial blood pressure. Materials and Methods: Initially, a suitable dynamic model is introduced for pulsatile blood flow in the arteries based on Navier-Stokes the equations in fluid mechanics. Then, according to the theory of elasticity, the equations governing arterial wall are described and coupled with the equations of fluid flow. The attained system of equations is completed by the clinical information obtained from the carotid artery Doppler ultrasound images of healthy male subject. Therefore, the Doppler ultrasound images are recorded and saved in computer after which the center-line blood velocity, the arterial wall thickness, the period of a cardiac cycle and the arterial radius are measured by off-line processing. Results: The results from the analytic solution of the completed equations show that the elastic modulus for this healthy subject is 51 kpa which is in close agreement with the result obtained from other researches. Discussion and Conclusion: By applying this method, a non-invasive method of clinically evaluating the arterial stiffness will be possible by the Doppler ultrasound measurement of common carotid artery without any measurement of the local blood pressure.

Coronary Calcium Screening and the American Heart Association News Embargo

Coronary calcium imaging with computed tomography (CT) for the detection of coronary artery disease has emerged as one of several novel measures of cardiovascular risk. These measures, which also include C-reactive protein, homocysteine, lipoprotein-a, the ankle-brachial index, and carotid intimal-medial thickness, have been the subject of considerable interest on the part of the medical profession and the media for a number of years. Their role in the primary prevention of cardiovascular disease has not been firmly established, however, and hence the American Heart Association (AHA) has not recommended their implementation on a population-wide basis. The AHA’s current position on CT scanning for coronary calcification has been articulated in 3 statements dating from 2000.1–3 When a physician is faced with a patient at intermediate risk, selected use of coronary calcium scores may be appropriate if the results have the potential to alter the treatment of the patient. The published literature does not yet, however, clearly define whether long-term patient outcomes can be improved by modifying treatment on the basis of coronary calcium scores. Thus, which asymptomatic individuals require or will benefit from CT scanning has not yet been determined with certainty. These statements pertain equally to the other emerging measures of risk noted above. Coronary scanning with CT has received increased media attention over the past few months, perhaps in the wake of reports of cardiovascular procedures performed on noteworthy public figures. Recent reports in the lay press suggested that the AHA’s position on this subject was about to change and that the Association would endorse this technology for atherosclerosis screening in asymptomatic individuals. These reports have led to an unfortunate level of speculation by the public and the medical community, principally because the statement of imminent support is simply incorrect: The AHA does not endorse devices, equipment, or medications, …

Distribution and Cross-Sectional Age-Related Increases of Carotid Artery Intima-Media Thickness in Young Adults

Reference values and age-related changes of carotid intima-media thickness (CIMT) have not been described in a community-based sample of young asymptomatic adults. CIMT measurements from the Bogalusa Heart Study, a study of the natural history of atherosclerosis in young adults and children, were used to characterize age-, race-, and sex-specific CIMT distributions and yearly rates of change. Age-, sex-, and race-specific CIMT percentile values and cross-sectional changes with age were estimated using B-mode carotid ultrasound images from 519 young adults (mean age 32 years, 61% female, 29% black). Nomograms of CIMT percentiles between the ages of 25 and 40 years are provided in 5-year increments. CIMT was thickest in the carotid bulb and increased linearly with age, most rapidly in the bulb. With age, composite CIMT increased most slowly in white females and most rapidly in white males. Sample size estimates projected that 268 to 462 subjects are needed to detect CIMT changes > or =0.010 mm/year. These estimated CIMT distributions and percentiles can serve as reference values for assessment of subclinical atherosclerosis in young adults. The observed age-related differences in CIMT can be used to plan epidemiological and clinical trials investigating atherosclerosis and anti-atherosclerotic interventions.

Methodology of the Cardiovascular Health and Age-Related Maculopathy (CHARM) Study

Age-related macular degeneration (AMD) is responsible for the majority of visual impairment in the Western world. Epidemiological studies examining risk factors for AMD are needed to develop strategies for the prevention of blindness from this condition. A number of potentially modifiable risk factors for AMD have been identified; however, only smoking has been a consistent risk factor across the numerous studies. A growing body of evidence suggests that AMD and cardiovascular disease may have common risk factors. The Cardiovascular Health and Age Related Maculopathy (CHARM) Study was established to examine the risk factors for AMD and its progression, in particular risk factors associated with cardiovascular disease.Examining risk factors for prevalent AMD, cases with AMD were compared with age and gender matched controls with no AMD features. For the assessment of AMD progression, the study examined in 2001 and 2002 those participants with early AMD, or age-related maculopathy (ARM), who had undergone baseline examination between 1992 and 1995 and compared the characteristics of those who had progression of AMD with those who did not. The CHARM study involved both ophthalmic and cardiovascular examinations. Standardised clinical eye examination and grading of the macular stereo photographs were used to determine the AMD status and progression. To examine cardiovascular status, carotid artery ultrasound imaging, analysis of systemic arterial compliance, augmentation index and pulse wave velocity were performed. The traditional and novel risk factors for CVD such as levels of glucose, cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, fibrinogen, C-reactive protein, immunoglobulins A and M, homocysteine, oxidized LDL and the exposure to the Chlamydia Pneumoniainfection were determined. DNA was collected for apolipoprotein E genotyping.The present paper outlines the primary aims of the CHARM study, the methodology involved and the recruitment results.

Causes of impaired consciousness while driving a motorized vehicle

T frequency of motor vehicle accidents in patients previously diagnosed with ventricular arrhythmias or vasovagal syncope has been reported.1–5 However, the converse, namely, the incidence of arrhythmias and vasovagal syncope in patients presenting with impaired consciousness while driving, has not been previously determined. This information is critical to help guide evaluation and management decisions and avoid future potentially lethal incidents. Our study examines the incidence of different etiologies of impaired consciousness while driving in motorists referred to the electrophysiologic service for evaluation. • • • We retrospectively reviewed the records of all patients who presented with impaired consciousness while driving personal or commercial vehicles between November 1985 and March 2000 at the Hospital of Saint Raphael, New Haven, Connecticut. Impaired consciousness was defined as syncope or presyncope. Patients were excluded if impaired consciousness was believed to be related to alcohol intoxication, illicit drug use, or as a secondary event as a result of the trauma of the accident. In all, 71 patients were identified with unexplained impaired consciousness while driving, and were referred to the electrophysiologic service for further evaluation. These 71 patients represent the study group. Medical history, physical examination, electrocardiogram, pertinent laboratory data, and chest x-ray were recorded in all patients. The results of Holter and electrocardiographic monitoring, echocardiography, carotid ultrasound, electroencephalography, and brain imaging were also collected and analyzed. All 71 patients underwent electrophysiologic evaluation in addition to routine workup for impaired consciousness. Electrophysiologic evaluation included tilt-table testing, electrophysiologic studies, and interrogation of implantable cardiac defibrillators, if present. Patients with structural heart disease underwent electrophysiologic study as the initial test, followed by tilttable testing if no etiology was convincingly demonstrated by the electrophysiologic study. Patients without evidence for structural heart disease underwent a tilttable test followed by electrophysiologic study; if they gave a cogent history of rapid palpitations accompanying the event, the electrophysiologic study was the initial diagnostic study. Patients who had a cardiac defibrillator had the device interrogated as the initial strategy, with further evaluation only if no tachyarrhythmic events in the device’s memory log were temporally correlated with the driving-related incident. The tilt-table test was performed by tilting the patients to 70° for 30 minutes. If the patient remained asymptomatic and had no known coronary disease, an isoproterenol infusion was begun and its rate titrated to increase the baseline heat rate by 25% for an additional 15 minutes. A tilt-table test was considered positive if syncope or presyncope was elicited with consistent hemodynamic changes and prodromal symptoms similar to the clinical event. During electrophysiologic study, a supraventricular tachycardia was considered the cause of impaired consciousness if a sustained supraventricular tachycardia could be induced, with or without isoproterenol, with accompanying adverse changes in hemodynamics. Ventricular tachycardia was only considered to be the cause of impaired consciousness if sustained monomorphic ventricular tachycardia could be elicited or if long bursts of symptomatic nonsustained ventricular tachycardia were seen. Advanced atrioventricular block was diagnosed if the block could be produced at paced cycle lengths 500 ms, or if spontaneous or procainamideinduced infra-Hisian block was noted. Baseline characteristics, cardiovascular history, and diagnostic testing of the study group are listed in Table 1.Three patients had 2 events while driving and 3 patients had 3 driving-related events. A presumptive diagnosis for impaired consciousness was made in 57 of 71 patients (80%) based on clinical findings and test results (Figure 1). Vasovagal syncope was diagnosed in 21 patients (30%) in whom a suggestive history was supported by a positive tilttable test result. Eighteen patients (25%) had supraventricular tachycardia induced during electrophysiologic study. Ventricular tachycardia was confirmed in 12 patients (17%). In 6 patients, ventricular tachycardia was found upon interrogation of their cardiac defibrillators after the accident. In another 6 patients, ventricular tachycardia was induced at electrophysiologic study. Advanced atrioventricular block was documented in 7 patients (10%), vestibular disease in 1 patient, and a seizure in 1 patient who had a negative electrophysiologic study result and a positive 24-hour ambulatory electroencephalograph. Three patients had a positive tilt-table test as well as inducible supraventricular tachycardia at electrophysiologic study and were included in both of the previously mentioned categories. Treatment based on these established diagnoses prevented recurrent episodes of impaired consciousFrom the Hospital of Saint Raphael and Yale University School of Medicine, New Haven, Connecticut. Dr. Schoenfeld’s address is: Cardiac Electrophysiology and Pacer Laboratory, Hospital of Saint Raphael, 330 Orchard Street, Suite 210, New Haven, Connecticut 06511. E-mail: Mschoenfeld@srhs.org. Manuscript received November 15, 2002; revised manuscript received and accepted February 12, 2003.

Regular exercise, hormone replacement therapy and the age-related decline in carotid arterial compliance in healthy women

Carotid arterial compliance is reduced with age in sedentary estrogen-deficient women, contributing to the development of cardiovascular disorders. We determined the effects of regular aerobic exercise, hormone replacement therapy (HRT), and their interaction on carotid arterial compliance using a combination of cross-sectional and intervention study designs. Cross-sectionally, we studied three groups of healthy postmenopausal women (50-80 years): 20 sedentary not taking HRT; 24 sedentary taking HRT; and 14 endurance-trained not taking HRT; and 11 sedentary premenopausal controls (20-37 years). In the intervention study, 12 sedentary postmenopausal women (58+/-3 years) who were taking HRT were studied before and after participation in a 3-month aerobic exercise (walking) program. Carotid arterial compliance was measured via simultaneous common carotid artery ultrasound imaging and applanation tonometry. Cross-sectional study. Carotid arterial compliance was lower (P<0.001) in all three postmenopausal groups compared with premenopausal women. Among the postmenopausal groups, arterial compliance was 33-43% higher in the sedentary HRT and endurance-trained women than in their sedentary estrogen-deficient peers. Intervention study. Arterial compliance increased (P<0.05) by approximately 40% to levels that were no longer different than premenopausal women. HRT use and regular aerobic exercise are associated with augmented carotid arterial compliance in healthy postmenopausal women. Moderate, short-term aerobic exercise can restore carotid arterial compliance in previously sedentary postmenopausal women taking HRT.

Atherosclerosis imaging to detect and monitor cardiovascular risk

Atherosclerosis imaging techniques, such as coronary computed tomography, carotid ultrasound, and vascular magnetic resonance imaging, accurately measure the extent of subclinical atherosclerosis as a biomarker of the effects of an individual patient’s coronary risk factors. Among the many potential applications of these tests, their greatest public health impact will be their use in the detection and management of cardiovascular risk. A growing body of data supports the application of these tests for the detection of cardiovascular risk, although further work is needed to document their additive diagnostic and management impact over measured risk factors and the global risk assessment. Each of these tests has a high degree of accuracy and reproducibility, creating the potential for serial imaging as a way to monitor cardiovascular risk by the detection of atherosclerosis progression, which is a known marker for an adverse cardiovascular prognosis.

Retinal arteriolar emboli: epidemiology and risk of stroke.

Retinal arteriolar emboli can be found in approximately 1% of adults more than 40 years of age. The frequency of retinal emboli increases with age and are more common in men than in women. Bilateral retinal emboli are rare, although multiple emboli in a single eye may be seen in up to one third of cases. Retinal emboli are associated with the presence of carotid artery plaque and stenosis, hypertension, cigarette smoking, and, possibly, diabetes. There are few prospective studies regarding the risk of stroke associated with retinal emboli. Available data suggest that retinal emboli in otherwise asymptomatic people are associated with a higher risk of stroke and stroke mortality, independent of conventional risk factors. Therefore, these patients are likely to benefit from a careful cardiovascular evaluation for risk stratification. Whether carotid ultrasound and other vascular imaging studies should be performed routinely for all patients with asymptomatic retinal emboli remains uncertain.

Prevalence of hypertension and carotid damage in stroke

To assess the relation between changes in the carotid arterial wall, blood pressure (BP) values and stroke we studied 140 consecutive patients with stroke (confirmed on CT scan). On admission blood pressure, ECG and carotids ultrasound imaging in standard points were assessed in order to evaluate the presence of intima-media thickness (IMT) (until 1.5 mm) and atheromatous plaques (AP) (above 1.5 mm). Also were evaluated, after 12 hrs fasting period of initial symptoms, plasma uric acid, cholesterol, triglycerides, HDL-C and Lp(a). The patients sample was divided in three groups according to ultrasound carotid image, normal carotid (group A), carotid with IMT (group B) and carotid with AP (group C). The table shows the results (mean±SEM) obtained and analyzed by ANOVA and, for those expressed as percentage values, by the X2 method. P<0.05 = $ A vs B, A vs C B vs C P<0.05 = $ A vs B, A vs C B vs C In the group A the stroke is prevalent hemorrhagic, it is significantly related with more elevated BP values respect to groups B and C and also it occurs in more young pts. In the group C there is an high incidence of ischemic stroke related to significant elevated cholesterol levels. In the group B the Lp(a) values are significantly more elevated than the other groups. Our data suggest than, in stroke pts, when cholesterol level is increased, atherosclerotic lesions responsible for ischemic cerebral disease, may represent the main risk factor; while, when cholesterol levels are normal, hypertension may be considered the mayor factor responsible for stroke, particularly the hemorrhagic one. Also, when Lp(a) concentration is increased can represent an early marker of carotid damage.