Showing papers by "Leslee J. Shaw published in 2006"

Assessment of coronary artery disease by cardiac computed tomography : A scientific statement from the american heart association committee on cardiovascular imaging and intervention, council on cardiovascular radiology and intervention, and committee on cardiac imaging, council on clinical cardiology

Abstract: This scientific statement reviews the scientific data for cardiac computed tomography (CT) related to imaging of coronary artery disease (CAD) and atherosclerosis. Cardiac CT is a CT imaging technique that accounts for cardiac motion, typically through the use of ECG gating. The utility and limitations of generations of cardiac CT systems are reviewed in this statement with emphasis on CT measurement of CAD and coronary artery calcified plaque (CACP) and noncalcified plaque. Successive generations of CT technology have been applied to cardiac imaging beginning in the early 1980s with conventional CT, electron beam CT (EBCT) in 1987, and multidetector CT (MDCT) in 1999. Compared with other imaging modalities, cardiac CT has undergone an accelerated …

From Vulnerable Plaque to Vulnerable Patient—Part III: Executive Summary of the Screening for Heart Attack Prevention and Education (SHAPE) Task Force Report

Abstract: Screening for early-stage asymptomatic cancers (eg, cancers of breast and colon) to prevent late-stage malignancies has been widely accepted. However, although atherosclerotic cardiovascular disease (eg, heart attack and stroke) accounts for more death and disability than all cancers combined, there are no national screening guidelines for asymptomatic (subclinical) atherosclerosis, and there is no governmentor healthcare-sponsored reimbursement for atherosclerosis screening. Part I and Part II of this consensus statement elaborated on new discoveries in the field of atherosclerosis that led to the concept of the “vulnerable patient.” These landmark discoveries, along with new diagnostic and therapeutic options, have set the stage for the next step: translation of this knowledge into a new practice of preventive cardiology. The identification and treatment of the vulnerable patient are the focuses of this consensus statement. In this report, the Screening for Heart Attack Prevention and Education (SHAPE) Task Force presents a new practice guideline for cardiovascular screening in the asymptomatic at-risk population. In summary, the SHAPE Guideline calls for noninvasive screening of all asymptomatic men 45‐75 years of age and asymptomatic women 55‐75 years of age (except those defined as very low risk) to detect and treat those with subclinical atherosclerosis. A variety of screening tests are available, and the cost-effectiveness of their use in a comprehensive strategy must be validated. Some of these screening tests, such as measurement of coronary artery calcification by computed tomography scanning and carotid artery intima‐media thickness and plaque by ultrasonography, have been available longer than others and are capable of providing direct evidence for the presence and extent of atherosclerosis. Both of these imaging methods provide prognostic information of proven value regarding the future risk of heart attack and stroke. Careful and responsible implementation of these tests as part of a comprehensive risk assessment and reduction approach is warranted and outlined by this report. Other tests for the detection of atherosclerosis and abnormal arterial structure and function, such as magnetic resonance imaging of the great arteries, studies of small and large artery stiffness, and assessment of systemic endothelial dysfunction, are emerging and must be further validated. The screening results (severity of subclinical arterial disease) combined with risk factor assessment are used for risk stratification to identify the vulnerable patient and initiate appropriate therapy. The higher the risk, the more vulnerable an individual is to a near-term adverse event. Because <10% of the population who test positive for atherosclerosis will experience a near-term event, additional risk stratification based on reliable markers of disease activity is needed and is expected to further focus the search for the vulnerable patient in the future. All individuals with asymptomatic atherosclerosis should be counseled and treated to prevent progression to overt

The Economic Burden of Angina in Women With Suspected Ischemic Heart Disease Results From the National Institutes of Health–National Heart, Lung, and Blood Institute–Sponsored Women’s Ischemia Syndrome Evaluation

Abstract: Background— Coronary angiography is one of the most frequently performed procedures in women; however, nonobstructive (ie, <50% stenosis) coronary artery disease (CAD) is frequently reported. Few data exist regarding the type and intensity of resource consumption in women with chest pain after coronary angiography. Methods and Results— A total of 883 women referred for coronary angiography were prospectively enrolled in the National Institutes of Health–National Heart, Lung, and Blood Institute–sponsored Women’s Ischemia Syndrome Evaluation (WISE). Cardiovascular prognosis and cost data were collected. Direct (hospitalizations, office visits, procedures, and drug utilization) and indirect (out-of-pocket, lost productivity, and travel) costs were estimated through 5 years of follow-up. Among 883 women, 62%, 17%, 11%, and 10% had nonobstructive and 1-vessel, 2-vessel, and 3-vessel CAD, respectively. Five-year cardiovascular death or myocardial infarction rates ranged from 4% to 38% for women with nonobstruc...

Roles of Nuclear Cardiology, Cardiac Computed Tomography, and Cardiac Magnetic Resonance: Noninvasive Risk Stratification and a Conceptual Framework for the Selection of Noninvasive Imaging Tests in Patients with Known or Suspected Coronary Artery Disease

Abstract: This review deals with noninvasive imaging for risk stratification and with a conceptual approach to the selection of noninvasive tests in patients with suspected or known chronic coronary artery disease (CAD). Already widely acknowledged with SPECT, there is an increasing body of literature data demonstrating that CT coronary calcium assessment is also of prognostic value. The amount of coronary atherosclerosis, as can be extrapolated from CT coronary calcium score, has been shown to be highly predictive of cardiac events. The principal difference between myocardial perfusion SPECT (MPS) and CT coronary calcium for prognostic application appears to be that the former is an excellent tool for assessing short-term risk, thus effectively guiding decisions regarding revascularization. In contrast, the atherosclerosis imaging methods are likely to provide greater long-term risk assessment and, thus, are more useful in determination of the need for aggressive medical prevention measures. Although the more recent development of CT coronary angiography is promising for diagnosis, there has been no information to date regarding the prognostic value of the CT angiographic data. Similarly, cardiac MRI has not yet been adequately studied for its prognostic content. The selection of the most appropriate test for a given patient depends on the specific question being asked. In patients with a very low likelihood of CAD, no imaging test may be required. In screening the remaining asymptomatic patients, atherosclerosis imaging may be beneficial. In symptomatic patients, MPS, CT coronary angiography, and cardiac MRI play important roles. We consider it likely that, with an increased emphasis on prevention and a concomitant aging of the population, many forms of noninvasive cardiac imaging will continue to grow, with nuclear cardiology continuing to grow.

Roles of Nuclear Cardiology, Cardiac Computed Tomography, and Cardiac Magnetic Resonance: Assessment of Patients with Suspected Coronary Artery Disease

Abstract: Noninvasive cardiac imaging is now central to the diagnosis and management of patients with known or suspected chronic coronary artery disease (CAD). Although rest echocardiography has become the most common of the techniques, nuclear cardiology and more recently cardiac computed tomography (CCT) and cardiac magnetic resonance (CMR) play important roles in this regard. This review examines the current applications and interactions of noninvasive cardiac imaging approaches for the assessment of patients with suspected CAD. In addition to considering the strengths and weaknesses of each technique, this review attempts to provide a guide to the selection of a test (or tests) that is based on the question being asked and the ability of each test to answer this question. In patients with suspected CAD, the pretest likelihood of disease, a clinical assessment, becomes the most important determinant of the initial test. If the likelihood is very low, no testing is needed. However, if the likelihood is low, recent data suggest that assessment of early atherosclerosis is likely to be the most useful and cost-effective test. In patients who have an intermediate likelihood of CAD, nuclear cardiology with myocardial perfusion SPECT (MPS) becomes highly valuable; however, coronary CT angiography (CTA), with fast 16-slice or greater scanners, may emerge as the initial test of choice. MPS would then be used if the CTA is inconclusive or if there is a need to assess the functional significance of a stenosis defined by CTA. Coronary CTA, however, is not yet widely available and is limited in patients with dense coronary calcification. In older patients with a high likelihood of CAD, MPS may be the initial test of choice, since a high proportion of these patients have too much coronary calcium to allow accurate assessment of the presence of coronary stenoses. PET/CT or SPECT/CT could emerge as important modalities combining the advantages of each modality. While CMR has great promise as a radiation-free and contrast-free "one-stop" shop, it currently lags behind CTA for noninvasive coronary angiography. Nonetheless, CMR clearly has the potential for this application and has already emerged as a highly effective method for assessing ventricular function, myocardial mass, and myocardial viability, and there is increasing use of this approach for clinical rest and stress perfusion measurements. CMR is particularly valuable in distinguishing ischemic from nonischemic cardiomyopathy. While CT and CMR are likely to grow considerably in diagnostic evaluation over the next several years, MPS and PET will continue to be very valuable techniques for this purpose.

Prognostic value of coronary artery calcium screening in asymptomatic smokers and non-smokers.

Abstract: Aims To determine the extent and prognostic significance of coronary artery calcium in asymptomatic smokers and non-smokers. Population data are available on the prognostic impact of smoking on atherosclerotic imaging measurements of the carotid and peripheral arteries. Limited data are available on the impact of cigarette smoking on the prognostic value of coronary calcium. Methods and results A referred patient registry of 10 377 asymptomatic individuals (40% were current smokers) was followed for death from all-causes at 5 years. Univariable and multivariable Cox proportional hazard models were calculated to estimate time to all-cause mortality. Cumulative 5-year survival was 96.9 and 98.4% for smokers when compared with non-smokers ( P 1000 ( P 1000 ( P 1000 was associated with a relative risk ratio that was elevated 8.9-fold ( P =0.029). Thus, resulting in an expected reduction in life expectancy of 4.8 years for smokers 400 ( P <0.0001). Conclusion The prognostic value of coronary artery calcium scoring was accurate in identifying a high-risk cohort of asymptomatic smokers and non-smokers. Young smokers with high-risk calcium scores have a four- to nine-fold increased risk of dying when compared with similarly aged non-smokers. When prospectively applied, evidence of a high-risk calcium score may be useful in educating patients as to their expected risk of dying over the next 5 years.

A meta-analysis of safety and effectiveness of perioperative beta-blocker use for the prevention of cardiac events in different types of noncardiac surgery.

Abstract: OBJECTIVE Perioperative beta-blocker therapy has been proposed to improve outcome. Most of the trials conducted, however, lacked statistical power to evaluate the incidence of hard cardiac events and the relationship to the type of surgery. Therefore, we conducted a meta-analysis of all randomized controlled trials in which beta-blocker therapy was evaluated. METHODS An electronic search of published reports on Medline was undertaken to identify studies published between January 1980 and November 2004 in English language journals. All studies reported on at least one of three endpoints: perioperative myocardial ischemia, perioperative nonfatal myocardial infarction, and cardiac mortality. Type of surgery, defined as low, intermediate, and high risk according to the American College of Cardiology/American Heart Association guidelines, was noted. RESULTS In total, 15 studies were identified, which enrolled 1,077 patient. No significant differences were observed in baseline clinical characteristics between patients randomized to beta-blocker therapy and control/placebo. Beta-blocker therapy was associated with a 65% reduction in perioperative myocardial ischemia (11.0% vs. 25.6%; odds ratio 0.35, 95% confidence interval 0.23-0.54; P<0.001). Furthermore, a 56% reduction in myocardial infarction (0.5% vs. 3.9%, odds ratio 0.44, 95% confidence interval 0.20-0.97; P=0.04) and a 67% reduction (1.1% vs. 6.1%, odds ratio 0.33, 95% confidence interval 0.17-0.67; P=0.002) in the composite endpoint of cardiac death and nonfatal myocardial infarction were observed. No statistical evidence was observed for heterogeneity in the treatment effect in subgroups according to type of surgery (P for heterogeneity 0.2). CONCLUSION This meta-analysis shows that beta-blocker use in noncardiac surgical procedures is associated with a significant reduction of perioperative cardiac adverse events.

Accuracy of non-invasive techniques for diagnosis of coronary artery disease and prediction of cardiac events in patients with left bundle branch block: a meta-analysis.

Abstract: Purpose Non-invasive evaluation of coronary artery disease (CAD) in patients with left bundle branch block (LBBB) has limitations inherent to different tests, and the relative merits of these tests are unclear. This meta-analysis assessed the accuracy of the frequently used non-invasive techniques, including exercise electrocardiography (ECG), myocardial perfusion imaging (MPI) and stress echocardiography (SE), for detection of CAD and prediction of cardiac events in patients with LBBB.

Diagnostic and prognostic value of non-invasive imaging in known or suspected coronary artery disease

Abstract: The role of non-invasive imaging techniques in the evaluation of patients with suspected or known coronary artery disease (CAD) has increased exponentially over the past decade. The traditionally available imaging modalities, including nuclear imaging, stress echocardiography and magnetic resonance imaging (MRI), have relied on detection of CAD by visualisation of its functional consequences (i.e. ischaemia). However, extensive research is being invested in the development of non-invasive anatomical imaging using computed tomography or MRI to allow detection of (significant) atherosclerosis, eventually at a preclinical stage. In addition to establishing the presence of or excluding CAD, identification of patients at high risk for cardiac events is of paramount importance to determine post-test management, and the majority of non-invasive imaging tests can also be used for this purpose. The aim of this review is to provide an overview of the available non-invasive imaging modalities and their merits for the diagnostic and prognostic work-up in patients with suspected or known CAD.

Anger, Hostility, and Cardiac Symptoms in Women with Suspected Coronary Artery Disease: The Women's Ischemia Syndrome Evaluation (WISE) Study

Abstract: Objective: To determine the relationship of anger and hostility to angiographic coronary artery disease (CAD), symptoms, and functional status among women with suspected CAD. Methods: Data were collected from 636 women with suspected CAD referred for diagnostic angiography in the Women's Ischemia Syndrome Evaluation (WISE) Study. CAD was assessed as angiographic presence/absence of disease (≥50% stenosis in any epicardial coronary artery). Hostility/anger, angina, symptoms, and functional status were assessed by the Cook- Medley Hostility Inventory, Spielberger Anger Expression Scale, cardiovascular symptom history, and the Duke Activity Status Index. Results: Logistic regression revealed that anger-out (i.e., aggressive behavior in response to angry feelings) was independently associated with the presence/absence of angiographic CAD (OR = 1.09, CI 1.01-1.17). Anger and hostility were higher among women reporting increased cardiovascular symptoms. In women without angiographic CAD, those with nonanginal c...

Cardiovascular Disease Risk Stratification With Stress Single-Photon Emission Computed Tomography Technetium-99m Tetrofosmin Imaging in Patients With the Metabolic Syndrome and Diabetes Mellitus

Abstract: The metabolic syndrome represents a constellation of risk factors caused by insulin resistance, dyslipidemia, hypertension, and obesity, resulting in elevated coronary disease risk. From a multicenter prospective registry of 7,849 patients, the relation among the metabolic syndrome, diabetes, and risk stratification with stress technetium-99m tetrofosmin single photon-emission computed tomography (SPECT) was evaluated. The percentage of stress myocardial defects was calculated as ≤5%, 5.1% to 10%, 10.1% to 15%, and >15%. A Cox proportional-hazards model was used to estimate cardiovascular death or myocardial infarction (n = 752). Of 7,849 patients, 42% had the metabolic syndrome. Patients with the metabolic syndrome had an 84% 2-year event-free survival rate, lower than patients with normal metabolic status (p 5% to >15% stress myocardial perfusion defects. In conclusion, cardiovascular prognosis is affected by the degree of metabolic dysfunction, and stress-induced reductions in myocardial perfusion provide an accurate means for near-term risk stratification.

Obesity distribution and reproductive hormone levels in women: a report from the NHLBI-sponsored WISE Study.

Abstract: Purpose: Relationships between body weight and disease are not straightforward. Central obesity appears to be a relatively greater cardiovascular risk factor than generalized obesity. The purpose of this study was to evaluate body mass index (BMI) and waist circumference and the association of obesity distribution with blood estrogen levels (estradiol, bioavailable estradiol, and estrone). Methods: The study cohort consisted of 207 postmenopausal women enrolled in the Women’s Ischemia Syndrome Evaluation (WISE) undergoing angiography for evaluation of suspected ischemia. Results: Both BMI and waist circumference were positively associated with all three blood estrogen levels (p < 0.01), with the highest estrogen levels found in the obese women with large waists (p < 0.01). Results from regression analyses confirmed significant associations of BMI and waist circumference with the estrogen levels. Conclusions: These results demonstrate differing relationships between blood estrogen levels and obesity distri...

Coronary artery disease: diagnostic and prognostic models for reducing patient risk.

Abstract: Early and accurate diagnostic testing is a critical factor in the detection and optimal management of coronary artery disease (CAD); thus, noninvasive cardiac imaging has become a central tool for CAD evaluation. Currently, tests used for evaluating CAD include conventional resting and stress electrocardiogram, echocardiography, and myocardial perfusion imaging--the most widely used imaging test for evaluation of suspected myocardial ischemia. Emerging techniques for noninvasive assessment of myocardial perfusion and coronary angiography include cardiac computed tomography, cardiac magnetic resonance imaging, and positron emission tomography. The distinctive pathophysiology of atherosclerosis can be used together with imaging techniques to diagnose and assess risk for CAD. Imaging modalities for cardiac risk stratification include a diverse array of tools, such as noninvasive tests that visualize presymptomatic atherosclerosis to sophisticated radionuclide protocols that identify myocardial viability. Of the noninvasive imaging tests, gated SPECT is the most accurate method for risk stratification of CAD. Myocardial perfusion imaging with SPECT has improved accuracy and image quality such that a shift from diagnostic to prognostic use has occurred. Radionuclide myocardial perfusion imaging has played an important role in CAD evaluation since the introduction of thallium-201 (Tl-201) in the 1970s. Although Tl-201 has high sensitivity, specificity, and reproducibility, it also has physical properties that limit its use and affect image quality. Currently, Tc-99m tetrofosmin and sestamibi are the most commonly used agents for a variety of resting and stress protocols, both have similar diagnostic accuracy profiles. The field of nuclear cardiology has grown steadily over the past few decades, as more practitioners recognize its clinical applications and value in managing cardiovascular disease. There is abroad spectrum of noninvasive and invasive testing available for the diagnosis and management of patients with cardiovascular disease. Advances in computer technology have made sophisticated devices, such as the gated SPECT, a routine part of cardiology.

Comparison of atherosclerotic calcification burden in persons with the cardiometabolic syndrome and diabetes.

Abstract: The cardiometabolic syndrome (CMS) and diabetes are associated with higher cardiovascular risk. The authors compared the association of CMS risk factors and diabetes with coronary and aortic calcium. A total of 4468 adults (42% female) underwent computed tomography for determination of coronary artery calcium (CAC) and thoracic aortic calcium (TAC) and were classified according to the presence of diabetes mellitus (DM) and number of CMS risk factors. The prevalence of CAC ranged from 51% in men and 35% in women with neither DM nor CMS to 75% in men and 58% in women with both DM and CMS, whereas TAC ranged from 29% to 44% in men and 36% to 55% in women. Women with four or five CMS risk factors more often had CAC (53%) and TAC (51%) than those with DM without CMS (40% and 35%, respectively) (p<0.001 across all disease groups). Adjusted odds (and 95% confidence intervals) of CAC for those with three CMS risk factors, four CMS risk factors, DM without CMS, and DM with CMS vs. those without CMS were 1.14 (0.93-1.39), 1.46 (1.12-1.90), 1.59 (1.06-2.38), and 2.10 (1.52-2.90) for CAC and 1.14 (0.91-1.42), 1.03 (0.77-1.37), 1.03 (0.68-1.54), and 1.41 (1.03-1.92) for TAC. Multiple CMS risk factors are associated with increased CAC, but not TAC; DM with CMS has the highest prevalence of CAC and TAC.

Abstract 4178: Cardiovascular Event-Free Survival in Post-Menopausal Women with Polycystic Ovary Syndrome: Results from the Women’s Ischemia Syndrome Evaluation

Abstract: Background: Women with polycystic ovary syndrome (PCOS) have a greater frequency and clustering of cardiac risk factors. Despite this, the link between PCOS and cardiovascular disease has not been ...