Comparison of coronary artery calcium scores between electron beam computed tomography and 64-multidetector computed tomographic scanner.

Objective: Because almost all data currently available with coronary calcium scanning are from electron beam tomography (EBT), we assessed whether scores obtained with 64-multidetector computed tomography (CT; MDCT) are similar. We evaluated the interscan variation in coronary artery calcium (CAC), Agatston score (AS), and volume score (VS) between EBT and 64-MDCT (VCT; GE, Milwaukee, Wis).

Materials And Methods: One hundred two patients (mean age, 61.

Applications of computed tomography in clinical cardiac electrophysiology.

The fields of noninvasive cardiac imaging and clinical cardiac electrophysiology have both benefited from improved technology and techniques in recent years. Evidence is growing that improved noninvasive imaging techniques may shorten procedure times and improve procedural success rates. Because this application of noninvasive imaging represents an emerging area of interest, robust clinical trial data about the effect of cardiac computed tomography (CT) on clinical endpoints is lacking.

Expert review on coronary calcium.

While there is no doubt that high risk patients (those with >20% ten year risk of future cardiovascular event) need more aggressive preventive therapy, a majority of cardiovascular events occur in individuals at intermediate risk (10%-20% ten year risk). Accurate risk assessment may be helpful in decreasing cardiovascular events through more appropriate targeting of preventive measures. It has been suggested that traditional risk assessment may be refined with the selective use of coronary artery calcium (CAC) or other methods of subclinical atherosclerosis measurement.

Cardiopulmonary exercise testing and six-minute walk correlations in pulmonary arterial hypertension.

In a clinical trial of 178 patients with pulmonary arterial hypertension, treatment improved the 6-minute walk (6MW) distance but not the peak VO2. To clarify this discrepancy, we examined the exercise data from all study sites. Patients received either the endothelin receptor antagonist sitaxsentan or placebo and underwent serial 6MW and cardiopulmonary exercise testing (CPET).

Methodology for improved detection of coronary stenoses with computed tomographic angiography.

Background: Noninvasive angiography is a promising technique for visualization of the coronary lumen; however, current methodologies lead to limited accuracy. We assessed the accuracy of electron beam computed tomographic angiography (EBA) for detection of coronary stenoses, using improved triggering techniques and thinner slice collimation.

Methods: Eighty-six patients with suspected coronary disease were studied with EBA and conventional invasive coronary angiography.

Clinical utility of computed tomography and magnetic resonance techniques for noninvasive coronary angiography.

Objective: The purpose of this study was to provide a comprehensive review of the literature relating to electron beam angiography (EBA), magnetic resonance angiography, and spiral computed tomography, currently the three most promising noninvasive methods to visualize obstructions in the coronary tree.

Background: Given the high costs and invasiveness of coronary angiography, there is increased interest in noninvasive coronary angiography, which has made great strides to become a clinically useful tool to augment conventional coronary angiography (CCA).

Methods: MEDLINE searches were performed to include all articles related to noninvasive angiography utilizing either magnetic resonance imaging (MRI), multi-row detector spiral computed tomography (MDCT), and electron beam tomography (EBT).

Atherosclerosis imaging and calcified plaque: coronary artery disease risk assessment.

Over the last decade, there has been increased recognition that atherosclerosis imaging adds greatly to the ability to identify patients at high risk for cardiac events. Technologies such as electron beam computed tomography and carotid intimal media thickness have contributed significantly to our understanding of the prevalence of preclinical atherosclerosis and its consequences. Guidelines and policy toward these modalities have shifted, with increased recognition of the importance among experts in cardiology, lipidology, and preventive medicine.

Measurement of the RT interval on ECG records during electron-beam CT.

Rationale And Objectives: The R wave of the electrocardiogram is used widely as a trigger for cardiac imaging. This study was designed to determine the optimal interval between the R wave and end systole for triggering of electron-beam computed tomography (CT) in a group of patients with various heart rates who are undergoing assessment for coronary artery calcification.

Materials And Methods: A total of 862 consecutive asymptomatic patients referred for screening with electron-beam CT for coronary artery calcification were enrolled in the study.

Causes of interscan variability of coronary artery calcium measurements at electron-beam CT.

Rationale And Objectives: The authors performed this study to investigate the causes of interscan variability of coronary artery calcium measurements at electron-beam computed tomography (CT).

Materials And Methods: Two sets of electron-beam CT scans were obtained in 298 consecutive patients who underwent electron-beam CT to screen for coronary artery calcium. Interscan variations of coronary artery calcium characteristics and the effects of heart rate, electrocardiographic (ECG) triggering method, image noise, and coronary motion on interscan variability were analyzed.

Electron beam tomography and angiography: sex differences.

Background: We sought to study a large cohort of symptomatic women to determine the clinical use of electron beam tomography (EBT), with evaluation of the sensitivity and specificity of obstructive coronary disease and the differences between premenopausal and postmenopausal cohorts.

Methods: Patients who underwent angiography for evaluation of coronary artery disease (CAD) and EBT within 3 months were enrolled. Receiver operating characteristic curves were used to establish relationships between EBT calcium scores and angiographic disease.

Primary angioplasty and selection bias inpatients presenting late (>12 h) after onset of chest pain and ST elevation myocardial infarction.

Objectives: This study was designed to compare the in-hospital outcome of patients presenting with >12 h from onset of chest pain and acute ST elevation myocardial infarction (AMI) who received either immediate invasive or conservative therapy.

Background: The benefits of fibrinolytic therapy diminish in patients presenting with AMI and onset of chest pain >12 h. Primary angioplasty has been suggested as a possible treatment for such patients, but they have been excluded from most trials of primary angioplasty.

Coronary artery disease progression assessed by electron-beam computed tomography.

The ability to observe changes in atherosclerotic plaque burden over time should provide an accurate measure of efficacy for different cardiovascular therapies. Electron-beam computed tomography (EBCT), by quantification of coronary artery calcification, is a noninvasive measure of atherosclerosis burden. This article summarizes data from abstracts and publications related to coronary artery calcium measurement and its use in progression studies.

Coronary artery motion during the cardiac cycle and optimal ECG triggering for coronary artery imaging.

Rationale And Objectives: Our purpose was to investigate the motion characteristics of the coronary arteries and determine optimal electrocardiographic (ECG) trigger time during the cardiac cycle to minimize motion artifacts.

Methods: Contrast-enhanced multislice movie studies of electron beam tomography (EBT) images were performed on 70 subjects. The EBT datasets, which covered an entire cardiac cycle at 58-ms intervals, were acquired for a short-axis view of the heart with ECG triggering.

Accurate measures of left ventricular ejection fraction using electron beam tomography: a comparison with radionuclide angiography, and cine angiography.

Background: Quantitative determination of ejection fraction is predicated on precise measurement of end-diastolic and end-systolic volumes of the left ventricle. Contrast enhanced electron beam tomography (EBT), with excellent temporal and spatial resolution, has the potential for highly accurate measures of ejection fraction.

Methods: EBT protocol used a short axis scan of the left ventricle (8-12 levels, apex to base) during infusion of iodinated contrast.

A simple single slice method for measurement of left and right ventricular enlargement by electron beam tomography.

Rationale And Objective: We devised to test the feasibility of measuring the left and right ventricular sizes by non-contrast electron beam tomographic images.

Methods: Ventricular sizes consist of the sum of the intracavitary cavity and myocardial mass for each ventricle. A total of 50-image studies from subjects undergoing contrast-enhanced studies were used to develop the measurement methodology.

Comparison of spiral and electron beam tomography in the evaluation of coronary calcification in asymptomatic persons.

Recently, investigators have begun evaluating the ability of spiral computed tomography (sequence scan mode-SEQ) to measure coronary calcium. Electron Beam Tomography (EBT) and SEQ studies were performed in 10 women and 23 men, with a mean age of 54+/-9 years. The EBT study was performed within 4 weeks (mean 11+/-4 days) of the SEQ with no clinical interval event (MI, revascularization).

Preview method for electron-beam CT scanning of the coronary arteries.

Rationale And Objectives: The purpose of this study was to evaluate a method that uses electron-beam computed tomography to obtain the most appropriate starting level for complete imaging of the coronary tree and to compare it with the existing method. A second aim was to evaluate the spatial location of the coronary arteries relative to different anatomic cardiac and chest landmarks.

Materials And Methods: Two hundred forty consecutive patients were randomly assigned to imaging with either a six-level preview (new) method or the traditional preview method.

Exercise testing and electron beam computed tomography in the evaluation of coronary artery disease.

Objectives: This study compared coronary artery calcium (CC) as detected by electron beam computed tomography (EBCT) with conventional stress testing in the evaluation of patients with symptoms suggestive of coronary artery disease (CAD).

Background: Exercise electrocardiogram treadmill stress testing (treadmill-ECG) is limited by its requirement of a normal resting ECG and the ability of the patient to exercise adequately. The addition of myocardial imaging agents such as technetium improves the sensitivity and specificity but substantially increases the cost and prolongs the testing time.

Rates of progression of coronary calcium by electron beam tomography.

In this study, we sought to determine the rate of progression of atherosclerosis using coronary calcium scores derived from electron beam tomography (EBT). We studied a variety of disease states (hypertension, high cholesterol, tobacco use, diabetes mellitus) followed for 1 to 6.5 years.

Evaluation of fluid collection in the pericardial sinuses and recesses: noncontrast-enhanced electron beam tomography.

Rationale And Objectives: To evaluate the attenuation, size, and volume of the pericardial sinuses and recesses by using electrocardiographically triggered, noncontrast-enhanced electron beam tomography (EBT) and to consider its relation with sex, age, and heart volume.

Methods: Findings in 213 consecutive patients without known pericardial disease were studied. The patients underwent EBT scanning of the heart to evaluate coronary artery calcification.

Electron beam computed tomography: calcification and lipid lowering interventions.

Over 50% of myocardial infarctions lead to sudden death without any prior warning signs or previously known coronary disease (1). Thus, persons with preclinical atherosclerosis must be identified prior to the onset of angina, MI, stroke or death. It has been estimated that primary prevention can avert more than 100,000 premature deaths each year in the United States alone and 10 times that worldwide (2).