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Publications (7)20.26 Total impact

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    ABSTRACT: BACKGROUND: Although numerous trials have demonstrated the diagnostic accuracy of coronary artery calcium (CAC) scanning for prediction of obstructive disease, virtually all studies have been performed using Electron Beam CT (EBCT). We evaluated the diagnostic accuracy of CAC by 64-row CT to detect obstructive coronary stenosis compared to quantitative coronary angiography (QCA) in the ACCURACY multicenter trial. METHODS: 16 sites prospectively enrolled 230 patients (pts) [59.5% males, 57yrs] with chest pain referred for invasive coronary angiography (ICA). Pts underwent CAC scan and CT angiography prior to ICA. Total CAC scores were correlated with angiographically documented stenoses using common cutpoints of CAC >0, >100 and >400. Significant obstructive disease was defined as >50% luminal stenosis by QCA. RESULTS: The per-patient accuracy of CAC by 64-row CT compared to QCA demonstrates a high sensitivity and low specificity for the presence of obstructive disease (>50% stenosis on QCA). With CAC >0, >100 and >400, the sensitivities to predict stenosis were 98%, 88%, and 60%, whereas the specificities were 42%, 71%, and 88%, respectively. CONCLUSIONS: Most previous CAC studies have focused on the fact that significant calcium places patients into a higher risk group in terms of future events, and should lead to more aggressive treatment with preventative therapies. This prospective multicenter results comparing 64-row CAC to QCA demonstrate that CAC using 64-row CT scanner, similar to previously published reports using EBCT, is highly sensitive and moderately specific test to predict significant coronary artery stenosis. The presence of abnormal levels of calcium may place patients into a higher risk group in terms of future events, and lead to more aggressive treatment with preventative therapies. However, the detection of calcium does not always help with a clinical diagnosis particularly in the presence of diffuse moderate coronary atheroma. Whether this information is complementary to CTA data remains to be validated.
    International journal of cardiology 12/2011; · 6.18 Impact Factor
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    ABSTRACT: The purpose of this study was to evaluate the diagnostic accuracy of electrocardiographically gated 64-multidetector row coronary computed tomographic angiography (CCTA) in individuals without known coronary artery disease (CAD). CCTA is a promising method for detection and exclusion of obstructive coronary artery stenosis. To date, no prospective multicenter trial has evaluated the diagnostic accuracy of 64-multidetector row CCTA in populations with intermediate prevalence of CAD. We prospectively evaluated subjects with chest pain at 16 sites who were clinically referred for invasive coronary angiography (ICA). CCTAs were scored by consensus of 3 independent blinded readers. The ICAs were evaluated for coronary stenosis based on quantitative coronary angiography (QCA). No subjects were excluded for baseline coronary artery calcium score or body mass index. A total of 230 subjects underwent both CCTA and ICA (59.1% male; mean age: 57 +/- 10 years). On a patient-based model, the sensitivity, specificity, and positive and negative predictive values to detect > or =50% or > or =70% stenosis were 95%, 83%, 64%, and 99%, respectively, and 94%, 83%, 48%, 99%, respectively. No differences in sensitivity and specificity were noted for nonobese compared with obese subjects or for heart rates < or =65 beats/min compared with >65 beats/min, whereas calcium scores >400 reduced specificity significantly. In this prospective multicenter trial of chest pain patients without known CAD, 64-multidetector row CCTA possesses high diagnostic accuracy for detection of obstructive coronary stenosis at both thresholds of 50% and 70% stenosis. Importantly, the 99% negative predictive value at the patient and vessel level establishes CCTA as an effective noninvasive alternative to ICA to rule out obstructive coronary artery stenosis. (A Study of Computed Tomography [CT] for Evaluation of Coronary Artery Blockages in Typical or Atypical Chest Pain; NCT00348569).
    Journal of the American College of Cardiology 12/2008; 52(21):1724-32. · 14.09 Impact Factor
  • David C. Levin, David Albert Dowe
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    ABSTRACT: LEARNING OBJECTIVES 1) Learn coronary artery anatomy. 2) Identify anatomic variations and pitfalls. 3) Develop knowledge of coronary artery disease patterns. 4) Understand how to image process and interpret CT coronary angiograms. 5) Become aware of the techniques and current capabilities of CT coronary angiography. ABSTRACT Coronary artery disease is the # 1 killer in this country, and the development of new noninvasive CT techniques to image those vessels is perhaps the most important single advance in imaging so far this century. Until now, the only noninvasive imaging methods of detecting coronary disease have been indirect ones like stress nuclear perfusion scans, stress echocardiography, and coronary calcium scoring. Direct visualization of the coronary arteries in past years has required cardiac catheterization - an invasive and expensive technique with some risk (albeit small). The advent of coronary CTA gives radiologists the opportunity to reassert their role in diagnosing this ubiquitous disease. This course will teach registrants about the basics of coronary artery anatomy, anatomic variations, pitfalls, and disease patterns. The first half will use catheter-based coronary angiograms to demonstrate these points. During the second half, coronary CTAs will be shown to illustrate the same things. The ultimate purpose of the program is to instruct registrants in how to interpret coronary CTAs and to relate the CT findings to what they have learned about coronary anatomy and coronary disease. Some emphasis will also be placed on new observations about disease patterns, such as positive remodeling and vessel wall morphology, which were not well understood prior to the development of coronary CTA. It is vitally important that radiologists become as knowledgeable as possible and actively involved in this field.
    Radiological Society of North America 2007 Scientific Assembly and Annual Meeting; 11/2007
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    ABSTRACT: PURPOSE Although single-center studies have shown promise for non-invasive angiography by 64-row computed tomographic coronary angiography (CCTA), no prospective multicenter trial has yet been performed. This study evaluated the diagnostic accuracy of 64-row CCTA to detect obstructive coronary stenosis compared to quantitative coronary angiography (QCA). METHOD AND MATERIALS 16 U.S. sites prospectively enrolled 232 patients (pts) [59.5% male, 57 yrs; body mass index 31.4; coronary artery calcium score 301] with typical or atypical chest pain referred for invasive coronary angiography (ICA). Pts underwent CCTA (Lightspeed VCT/Visipaque, GE Healthcare, London, UK) prior to ICA. CCTAs were graded on a 15-segment AHA model by 3 blinded readers for presence of obstructive stenosis (�50% or �70%) by consensus (�2 of 3); ICAs were independently graded for % stenosis by QCA, which served as the reference standard. Efficacy of CCTA was assessed including all vessel segments of all sizes (�2mm and <2mm) irrespective of baseline coronary artery calcium score for per-patient and per-vessel analyses. RESULTS A total of 82 �50% stenoses in 49 (21.3%prevalence) pts, and 31 �70% stenoses in 28 (12.1% prevalence) pts, were identified by QCA. Diagnostic accuracy was high for per-patient and per-vessel analyses of CCTA compared to QCA to detect a >70% coronary artery stenosis, with sensitivity, specificity, PPV and NPV of 91%, 84%, 51%, 98% and 85%, 92%, 68%, 99%, respectively. Diagnostic accuracy of CCTA was also high for per-patient and per-vessel analyses to detect a >50% coronary artery stenosis, with sensitivity, specificity, PPV and NPV of 93%, 82%, 62%, 97% and 84%, 91%, 49%, 98%, respectively. CONCLUSION These data represent the first prospective multicenter results comparing 64-row CCTA to QCA without exclusion based upon baseline coronary artery calcium score or body mass index, and demonstrate high accuracy of CCTA to reliably detect �50% and �70% stenosis in chest pain pts being referred for ICA. The high negative predictive values observed (97-99%) indicate that CCTA is also an effective non-invasive method to exclude obstructive coronary stenosis.
    Radiological Society of North America 2007 Scientific Assembly and Annual Meeting; 11/2007
  • David Carl Levin, David Albert Dowe
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    ABSTRACT: LEARNING OBJECTIVES 1) Learn coronary artery anatomy. 2) Identify anatomic variations and pitfalls. 3) Develop knowledge of coronary artery disease patterns. 4) Understand how to image process and interpret CT coronary angiograms. 5) Become aware of the techniques and current capabilities of CT coronary angiography. ABSTRACT Coronary artery disease is the # 1 killer in this country, and the development of new noninvasive CT techniques to image those vessels is perhaps the most important single advance in imaging so far this century. Until now, the only noninvasive imaging methods of detecting coronary disease have been indirect ones like stress nuclear perfusion scans, stress echocardiography, and coronary calcium scoring. Direct visualization of the coronary arteries in past years has required cardiac catheterization - an invasive and expensive technique with some risk (albeit small). The advent of coronary CTA gives radiologists the opportunity to reassert their role in diagnosing this ubiquitous disease. This course will teach registrants about the basics of coronary artery anatomy, anatomic variations, pitfalls, and disease patterns. The first half will use catheter-based coronary angiograms to demonstrate these points. During the second half, coronary CTAs will be shown to illustrate the same things. The ultimate purpose of the program is to instruct registrants in how to interpret coronary CTAs and to relate the CT findings to what they have learned about coronary anatomy and coronary disease. Some emphasis will also be placed on new observations about disease patterns, such as positive remodeling and vessel wall morphology, which were not well understood prior to the development of coronary CTA. It is vitally important that radiologists become as knowledgeable as possible and actively involved in this field.
    Radiological Society of North America 2006 Scientific Assembly and Annual Meeting; 12/2006
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    ABSTRACT: PURPOSE To evaluate the prevalence, diagnostic and therapeutic significance of noncardiac findings in coronary computed tomography angiography scans performed to assess coronary artery stenosis and plaque burden. METHOD AND MATERIALS We conducted a retrospective study of 1735 patients between the ages of 14 and 90 years with known or suspected coronary artery disease. These subjects underwent a coronary computed tomography angiography using 16 and 64 slice CT scanners. The observed noncardiac findings were gathered from the entire field of view of the scans. RESULTS A total of 701 noncardiac findings were observed in 542 (31%) patients. The most frequent were lung parenchyma and pleural lesions found in 405 (23%) of the patients. The pulmonary findings comprised 191 cases of lung nodules (27% of total lesion number), 70 emphysema cases (10%), 55 granuloma cases (8%), 53 atelectasis cases (7.5%), 39 pulmonary infiltrate cases (5.5%) and 19 adenopathy cases (3%). Pulmonary nodules greater than 5mm constituted 10% of all noncardiac findings (72 cases) whereas nodules smaller or equal to 5mm 17% (118 cases). Other most commonly encountered findings were liver lesions (88 cases; 12.5% of total lesion number) and hiatal hernia (66; 9%). Neoplastic disease was newly diagnosed in 2 cases. CONCLUSION Noncardiac pathology is prevalent in coronary computed tomography angiography, and frequently necessitates diagnostic or therapeutic action and in some cases provides explanation for patient's symptomatology. CLINICAL RELEVANCE/APPLICATION Careful evaluation of the entire field of view of the coronary CT angiography scans performed to assess coronary artery disease is recommended, as it frequently reveals noncardiac pathology.
    Radiological Society of North America 2006 Scientific Assembly and Annual Meeting; 11/2006
  • David Carl Levin, David Albert Dowe
    [Show abstract] [Hide abstract]
    ABSTRACT: LEARNING OBJECTIVES 1) Learn coronary artery anatomy. 2) Identify anatomic variations and pitfalls. 3) Develop knowledge of coronary artery disease patterns. 4) Understand how to image process and interpret CT coronary angiograms. 5) Become aware of the techniques and current capabilities of CT coronary angiography. ABSTRACT Coronary artery disease is the # 1 killer in this country, and the development of new noninvasive CT techniques to image those vessels is perhaps the most important single advance in imaging so far this century. Until now, the only noninvasive imaging methods of detecting coronary disease have been indirect ones like stress nuclear perfusion scans, stress echocardiography, and coronary calcium scoring. Direct visualization of the coronary arteries in past years has required cardiac catheterization - an invasive and expensive technique with some risk (albeit small). The advent of coronary CTA gives radiologists the opportunity to reassert their role in diagnosing this ubiquitous disease. This course will teach registrants about the basics of coronary artery anatomy, anatomic variations, pitfalls, and disease patterns. The first half will use catheter-based coronary angiograms to demonstrate these points. During the second half, coronary CTAs will be shown to illustrate the same things. The ultimate purpose of the program is to instruct registrants in how to interpret coronary CTAs and to relate the CT findings to what they have learned about coronary anatomy and coronary disease. Some emphasis will also be placed on new observations about disease patterns, such as positive remodeling and vessel wall morphology, which were not well understood prior to the development of coronary CTA. It is vitally important that radiologists become as knowledgeable as possible and actively involved in this field.
    Radiological Society of North America 2005 Scientific Assembly and Annual Meeting; 11/2005