Coronary Artery Disease: Bluemke DA

Bluemke DA, Achenbach S, Budoff M, Gerber TC, Gersh B, Hillis LD, Hundley WG, Manning WJ, Printz BF, Stuber M, Woodard PK. · No affiliation provided · Circulation. · Pubmed #18586979 links to  free full text

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Sibley CT, Bluemke DA. · No affiliation provided · J Am Coll Cardiol. · Pubmed #19555844 No free full text.

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Flice R, Lima JA, Bluemke DA. · Department of Radiology and Radiological Sciences, Division of Cardiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA. · Top Magn Reson Imaging. · Pubmed #18025988 No free full text.

Abstract: Coronary events are the leading cause of death in the United States, and sudden coronary death is often the first presenting symptom. Because there is such a large population at risk for coronary events and because many of these patients go undetected before presenting with a significant cardiovascular event or sudden death, there is great interest in better detection and characterization of subclinical disease before it causes morbidity and mortality. This chapter will focus on promising imaging-based methods for the evaluation of subclinical cardiovascular disease. Several imaging methods that are most likely to be useful for future screening and intervention studies for characterizing risk among asymptomatic persons will be presented.

Weinreb JC, Larson PA, Woodard PK, Stanford W, Rubin GD, Stillman AE, Bluemke DA, Duerinckx AJ, Dunnick NR, Smith GG. · Yale University School of Medicine, New Haven, Connecticut, USA. <> · J Am Coll Radiol. · Pubmed #17411862 No free full text.

Abstract: Coronary artery disease and other acquired and congenital cardiac diseases are major medical and socio-economic problems. Historically, imaging has had a critical role in the diagnosis and evaluation of acquired and congenital cardiac disease. Advances in computed tomography (CT), with multidetector CT and electron beam CT technology, and magnetic resonance (MR) imaging, now make it possible to noninvasively image the coronary arteries, cardiac chambers, valves, myocardium, and pericardium and assess cardiac function, and CT and MR imaging are becoming increasingly important in the evaluation of cardiac disease. Radiologists, because of their extensive experience in CT and MR imaging, have an important role in imaging cardiac patients using these modalities. This clinical statement of the ACR discusses various technical and patient safety issues related to cardiac CT and MR imaging, and it suggests appropriate qualifications for radiologists until such time as ACR practice guidelines for the performance of cardiac CT and cardiac MR imaging are written and approved through the usual ACR process. It stresses that the interpreting physician is responsible for examining not only the cardiac structures of interest but also all the visualized noncardiac structures and must report any clinically relevant abnormalities of these adjacent structures.

Vogel-Claussen J, Rochitte CE, Wu KC, Kamel IR, Foo TK, Lima JA, Bluemke DA. · Department of Radiology, Johns Hopkins Hospital, MRI, Room 143, 600 N Wolfe St, Baltimore, MD 21287, USA. · Radiographics. · Pubmed #16702455 links to  free full text

Abstract: Use of magnetic resonance (MR) imaging for diagnosis of cardiac diseases and treatment monitoring is expanding. Delayed myocardial enhancement MR imaging is performed after administration of paramagnetic contrast agents and is used for a growing number of clinical applications. This technique was developed primarily for characterization of myocardial scarring after myocardial infarction. On delayed enhancement MR images, scarring or fibrosis appears as an area of high signal intensity that is typically subendocardial or transmural in a coronary artery distribution. However, delayed myocardial enhancement is not specific for myocardial infarction and can occur in a variety of other disorders, such as inflammatory or infectious diseases of the myocardium, cardiomyopathy, cardiac neoplasms, and congenital or genetic cardiac conditions, as well as after cardiac interventions. In nonischemic myocardial disease, the delayed enhancement usually does not occur in a coronary artery distribution and is often midwall rather than subendocardial or transmural. Therefore, the patient's clinical history is critical in the evaluation of delayed myocardial enhancement MR images.

Hillenbrand HB, Lima JA, Bluemke DA, Beache GM, McVeigh ER. · Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. · J Cardiovasc Magn Reson. · Pubmed #11545108 No free full text.

Abstract: Tagged magnetic resonance imaging (MRI) can assess myocardial function by tracking the motion of the myocardium during the various phases of the cardiac cycle. In contrast to experimental methods, such as implantation of radiopaque markers or sonomicrometry, tagged MRI is noninvasive, carries no risk of radiation exposure, and can be used in the context of clinical routine. For the physician, using tagged MRI to its fullest potential requires an understanding of the technique and the derived parameters of myocardial systolic function. This work describes the tagged MRI technique and explains the quantification of systolic function with respect to the underlying theory of the mechanics of a continuous medium. The advantages of tagged MRI in coronary artery disease are emphasized, and currently available data on tagged MRI in coronary artery disease are reviewed.

Reeder SB, Du YP, Lima JA, Bluemke DA. · Department of Radiology, Rm H1306, Stanford University, 300 Pasteur Dr, Stanford, CA 94304, USA. · Radiographics. · Pubmed #11452080 links to  free full text

Abstract: Important advances in rapid magnetic resonance (MR) imaging technology and its application to cardiovascular imaging have been made during the past decade. High-field-strength clinical magnets, high-performance gradient hardware, and ultrafast pulse sequence technology are rapidly making the vision of a comprehensive "one-stop shop" cardiac MR imaging examination a reality. This examination is poised to have a significant effect on the management of coronary artery disease by means of assessment of wall motion with tagging and pharmacologic stress testing, evaluation of the coronary microvasculature with perfusion imaging, and direct visualization of the coronary arteries with MR coronary angiography. This article reviews current state-of-the-art pulse sequence technology and its application to the evaluation of ischemic heart disease by means of MR tagging with dobutamine stress testing, MR perfusion imaging, and MR coronary angiography. Cutting edge areas of research in coil design and exciting new areas of metabolic and oxygen level-dependent imaging are also explored.

Folsom AR, Kronmal RA, Detrano RC, O'Leary DH, Bild DE, Bluemke DA, Budoff MJ, Liu K, Shea S, Szklo M, Tracy RP, Watson KE, Burke GL. · Division of Epidemiology & Community Health, School of Public Health, University of Minnesota, 1300 S Second St, Ste 300, Minneapolis, MN 55454-1015, USA. · Arch Intern Med. · Pubmed #18574091 links to  free full text

Abstract: BACKGROUND: Coronary artery calcium (CAC) and carotid intima-media thickness (IMT) are noninvasive measures of atherosclerosis that consensus panels have recommended as possible additions to risk factor assessment for predicting the probability of cardiovascular disease (CVD) occurrence. Our objective was to assess whether maximum carotid IMT or CAC (Agatston score) is the better predictor of incident CVD. METHODS: A prospective cohort study of subjects aged 45 to 84 years in 4 ethnic groups, who were initially free of CVD (n = 6698) was performed, with standardized carotid IMT and CAC measures at baseline, in 6 field centers of the Multi-Ethnic Study of Atherosclerosis (MESA). The main outcome measure was the risk of incident CVD events (coronary heart disease, stroke, and fatal CVD) over a maximum of 5.3 years of follow-up. RESULTS: There were 222 CVD events during follow-up. Coronary artery calcium was associated more strongly than carotid IMT with the risk of incident CVD. After adjustment for each other (CAC score and IMT) and age, race, and sex [corrected], the hazard ratio of CVD increased 2.1-fold (95% confidence interval [CI], 1.8-2.5) for each 1-standard deviation (SD) increment of log-transformed CAC score, vs 1.3-fold (95% CI, 1.1-1.4) for each 1-SD increment of the maximum IMT. For coronary heart disease, the hazard ratios per 1-SD increment increased 2.5-fold (95% CI, 2.1-3.1) for CAC score and 1.2-fold (95% CI, 1.0-1.4) for IMT. A receiver operating characteristic curve analysis also suggested that CAC score was a better predictor of incident CVD than was IMT, with areas under the curve of 0.81 vs 0.78, respectively. CONCLUSION: Although whether and how to clinically use bioimaging tests of subclinical atherosclerosis remains a topic of debate, this study found that CAC score is a better predictor of subsequent CVD events than carotid IMT.

Schmidt A, Azevedo CF, Cheng A, Gupta SN, Bluemke DA, Foo TK, Gerstenblith G, Weiss RG, Marbán E, Tomaselli GF, Lima JA, Wu KC. · Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, MD, USA. · Circulation. · Pubmed #17389270 links to  free full text

Abstract: BACKGROUND: The extent of the peri-infarct zone by magnetic resonance imaging (MRI) has been related to all-cause mortality in patients with coronary artery disease. This relationship may result from arrhythmogenesis in the infarct border. However, the relationship between tissue heterogeneity in the infarct periphery and arrhythmic substrate has not been investigated. In the present study, we quantify myocardial infarct heterogeneity by contrast-enhanced MRI and relate it to an electrophysiological marker of arrhythmic substrate in patients with left ventricular (LV) systolic dysfunction undergoing prophylactic implantable cardioverter defibrillator placement. METHODS AND RESULTS: Before implantable cardioverter defibrillator implantation for primary prevention of sudden cardiac death, 47 patients underwent cine and contrast-enhanced MRI to measure LV function, volumes, mass, and infarct size. A method for quantifying the heterogeneous infarct periphery and the denser infarct core is described. MRI indices were related to inducibility of sustained monomorphic ventricular tachycardia during electrophysiological or device testing. For the noninducible versus inducible patients, LV ejection fraction (30+/-10% versus 29+/-7%, P=0.79), LV end-diastolic volume (220+/-70 versus 228+/-57 mL, P=0.68), and infarct size by standard contrast-enhanced MRI definitions (P=NS) were similar. Quantification of tissue heterogeneity at the infarct periphery was strongly associated with inducibility for monomorphic ventricular tachycardia (noninducible versus inducible: 13+/-9 versus 19+/-8 g, P=0.015) and was the single significant factor in a stepwise logistic regression. CONCLUSIONS: Tissue heterogeneity is present and quantifiable within human infarcts. More extensive tissue heterogeneity correlates with increased ventricular irritability by programmed electrical stimulation. These findings support the hypothesis that anatomic tissue heterogeneity increases susceptibility to ventricular arrhythmias in patients with prior myocardial infarction and LV dysfunction.

Wolff SD, Schwitter J, Coulden R, Friedrich MG, Bluemke DA, Biederman RW, Martin ET, Lansky AJ, Kashanian F, Foo TK, Licato PE, Comeau CR. · Cardiovascular Research Foundation and Lenox Hill Hospital, New York, NY, USA. · Circulation. · Pubmed #15289374 links to  free full text

Abstract: BACKGROUND: MRI can identify patients with obstructive coronary artery disease by imaging the left ventricular myocardium during a first-pass contrast bolus in the presence and absence of pharmacologically induced myocardial hyperemia. The purpose of this multicenter dose-ranging study was to determine the minimally efficacious dose of gadopentetate dimeglumine injection (Magnevist Injection; Berlex Laboratories) for detecting obstructive coronary artery disease. METHOD AND RESULTS: A total of 99 patients scheduled for coronary artery catheterization as part of their clinical evaluation were enrolled in this study. Patients were randomized to 1 of 3 doses of gadopentate dimeglumine: 0.05, 0.10, or 0.15 mmol/kg. First-pass perfusion imaging was performed during hyperemia (induced by a 4-minute infusion of adenosine at a rate of 140 microg x kg(-1) x min(-1)) and then again in the absence of adenosine with otherwise identical imaging parameters and the same contrast dose. Perfusion defects were evaluated subjectively by 4 blinded reviewers. Receiver-operating curve analysis showed that the areas under the receiver-operating curve were 0.90, 0.72, and 0.83 for the low-, medium-, and high-contrast doses, respectively, compared with quantitative coronary angiography (diameter stenosis > or =70%). For the low-dose group, mean sensitivity was 93+/-0%, mean specificity was 75+/-7%, and mean accuracy was 85+/-3%. CONCLUSIONS: First-pass perfusion MRI is a safe and accurate test for identifying patients with obstructive coronary artery disease. A low dose of 0.05 mmol/kg gadopentetate dimeglumine is at least as efficacious as higher doses.

Edvardsen T, Gerber BL, Garot J, Bluemke DA, Lima JA, Smiseth OA. · Department of Cardiology, Rikshospitalet University, Oslo, Norway. · Circulation. · Pubmed #12093769 links to  free full text

Abstract: BACKGROUND: Tissue Doppler echocardiography-derived strain rate and strain measurements (SDE) are new quantitative indices of intrinsic cardiac deformation. The aim of this study was to validate and compare these new indices of regional cardiac function to measurements of 3-dimensional myocardial strain by tagged MRI. METHODS AND RESULTS: The study population included 33 healthy volunteers, 17 patients with acute myocardial infarction, and 8 patients with suspected coronary artery disease who were studied during dobutamine stress echocardiography. Peak systolic myocardial velocities were measured by tissue Doppler echocardiography, peak systolic strain rates and strains by SDE, and strains by tagged MRI. In healthy individuals, longitudinal myocardial Doppler velocities decreased progressively from base to apex, whereas myocardial strain rates and strains were uniform in all segments. In patients with acute infarction, abnormal strains clearly identified dysfunctional areas. In infarcted regions, SDE showed 1.5+/-4.3% longitudinal stretching compared with -15.0+/-3.9% shortening in remote myocardium (P<0.001), and radial measurements showed -6.9+/-4.1% thinning and 14.3+/-5.0% thickening (P<0.001), respectively. During dobutamine infusion, longitudinal strains by SDE increased significantly from -13.5% to -23.8% (P<0.01) and radial strains increased from 13.1+/-3.1% to 29.3+/-11.5% (P<0.01). Comparisons between myocardial strains by SDE and tagged MRI in healthy individuals (n=11), in infarct patients (n=17), and during stress echo (n=4) showed excellent correlations (r=0.89 and r=0.96 for longitudinal and radial strains, respectively, P< 0.001). CONCLUSIONS: The present study demonstrates the ability of Doppler echocardiography to measure myocardial strains in a clinical setting. Myocardial strains by Doppler may represent a new powerful method for quantifying left ventricular function noninvasively in humans.

Miao C, Chen S, Macedo R, Lai S, Liu K, Li D, Wasserman BA, Vogel-Claussen J, Vogel-Clausen J, Lima JA, Bluemke DA. · Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. · J Am Coll Cardiol. · Pubmed #19406347 No free full text.

Abstract: OBJECTIVES: The purpose of this study was to assess coronary arterial remodeling as a marker of subclinical atherosclerosis using coronary wall magnetic resonance imaging (MRI) in an asymptomatic population-based cohort. BACKGROUND: In early atherosclerosis, compensatory enlargement of both the outer wall of the vessel as well as the lumen, termed compensatory enlargement or positive remodeling, occurs before luminal narrowing. METHODS: One hundred seventy-nine participants in the MESA (Multi-Ethnic Study of Atherosclerosis) trial were evaluated using black-blood coronary wall MRI. Coronary cross-sectional area (vessel size), lumen area, and mean wall thickness of the proximal coronary arteries were measured. RESULTS: Men had a greater vessel size, lumen area, and mean wall thickness than women (38.3 +/- 11.3 mm2 vs. 32.6 +/- 9.4 mm2, 6.7 +/- 3.2 mm2 vs. 5.3 +/- 2.4 mm2, and 2.0 +/- 0.3 mm vs. 1.9 +/- 0.3 mm, respectively, p < 0.05). No significant coronary artery narrowing was present by magnetic resonance angiography. Overall, coronary vessel size increased 25.9 mm2 per millimeter increase in coronary wall thickness, whereas lumen area increased only slightly at 3.1 mm2 for every millimeter increase in wall thickness (difference in slopes, p < 0.0001). Adjusting for age and sex, participants with an Agatston score >0 were more likely to have wall thickness >2.0 mm (odds ratio: 2.0, 95% confidence interval: 1.01 to 3.84). CONCLUSIONS: Coronary wall MRI detected positive arterial remodeling in asymptomatic men and women with subclinical atherosclerosis.

Malayeri AA, Macedo R, Li D, Chen S, Bahrami H, Lai S, Lima JA, Bluemke DA. · Department of Radiology and Radiological Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. · J Comput Assist Tomogr. · Pubmed #19188777 No free full text.

Abstract: OBJECTIVE: Coronary artery wall magnetic resonance imaging (MRI) has been developed to assess coronary lumen diameter and wall thickness. The purpose of this study was to evaluate the physiological parameters that affect the measures of coronary wall thickness using black-blood MRI pulse sequences. METHODS: Eighty-seven participants (38 men and 49 women) of the Multi-Ethnic Study of Atherosclerosis were enrolled in the coronary artery wall MRI study. Cine 4-chamber imaging was used to determine the coronary artery rest period. Free-breathing whole-heart magnetic resonance angiography with motion adaptor navigator was performed to localize the coronary arteries in 64 participants. Cross-sectional free-breathing black-blood images were acquired using electrocardiogram-gated, turbo spin echo sequence. Imaging parameters were as follows: repetition time = 2 R-R intervals, time to echo = 33 milliseconds, echo train length = 13, bandwidth = 305 Hz/pixel, matrix = 416 x 416, field of view = 420 x 420 mm, and slice thickness = 4 to 5 mm. RESULTS: Imaging was completed in 215 (92%) of 234 coronary segments; 9 participants had incomplete scans. Mean age was 62.6 +/- 8.4 years (range, 45-81 years). Mean body mass index was 29.2 +/- 5.9 kg/m2. A higher proportion of images with quality of "good" was seen in the right coronary artery (40.5%) compared to the left main and left anterior descending coronary arteries (31.9% and 26.4%, respectively). There was a very good agreement between observers in the image quality scores (kappa = 0.79, P < 0.001). Lower heart rate, male sex, and longer coronary rest period were associated with higher image quality score (P < 0.05). Signal-to-noise ratio was higher in participants with Agatston calcium score of more than 10 in the right coronary and left main arteries (48.5 vs 69.7, P = 0.001; and 53.4 vs 61.6, P = 0.032, respectively). CONCLUSION: Improved depiction of the coronary artery wall with MRI is related to coronary rest period and atherosclerotic plaque burden as measured by calcium score and inversely related to heart rate. Because longer coronary artery rest periods are associated with improved image quality both for angiography with MRI and coronary artery wall imaging, heart rate-lowering methods in association with these techniques appear to be a logical application.

Rerkpattanapipat P, D'Agostino RB, Link KM, Shahar E, Lima JA, Bluemke DA, Sinha S, Herrington DM, Hundley WG. · Department of Public Health Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA. · Diabetes. · Pubmed #19136657 links to  free full text

Abstract: OBJECTIVE: To determine whether middle-aged and older individuals with impaired fasting glucose (IFG), but no clinical evidence of cardiovascular disease, exhibit abnormal changes in proximal thoracic aortic stiffness or left ventricular (LV) mass when compared with healthy counterparts. RESEARCH DESIGN AND METHODS: From the Multi-Ethnic Study of Atherosclerosis, 2,240 subjects with normal fasting glucose (NFG), 845 with IFG, and 414 with diabetes, all aged 45 to 85 years and without preexisting coronary artery disease, underwent MRI determinations of total arterial and proximal thoracic aortic stiffness and LV mass. The presence or absence of other factors known to influence arterial stiffness was assessed. RESULTS: After adjustment for clinical factors known to modify arterial stiffness, proximal thoracic aortic stiffness was not increased in those with IFG compared with those with NFG (1.90 +/- 0.05 versus 1.91 +/- 0.04 10(-3) mmHg(-1), respectively, P = 0.83). After accounting for clinical factors known to influence LV mass, LV mass was increased in those with diabetes relative to those with NFG (150.6 +/- 1.4 versus 145.8 +/- 0.81 g, P < 0.0009) but not in those with IFG in comparison with NFG (145.2 +/- 1.03 versus 145.8 +/- 0.81 g, P = 0.56). CONCLUSIONS: Middle-aged and older individuals with the pre-diabetes state of IFG do not exhibit abnormal proximal thoracic distensibility or LV hypertrophy relative to individuals with NFG. For this reason, an opportunity may exist in those with IFG to prevent LV hypertrophy and abnormal aortic stiffness that is observed in middle-aged and older individuals with diabetes.

Nasir K, Katz R, Mao S, Takasu J, Bomma C, Lima JA, Bluemke DA, Kronmal R, Carr JJ, Budoff MJ. · Cardiac MRI PET CT Program, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA. · J Cardiovasc Comput Tomogr. · Pubmed #19083938 No free full text.

Abstract: BACKGROUND: A non-contrast-enhanced cardiac computed tomography (NCE-CCT) scan for assessing coronary artery calcification (CAC) is being increasingly used for assessing underlying burden of atherosclerosis. Although many studies document the potential value of measuring CAC, little is known about the other measures such as left ventricular (LV) geometry that can be obtained from the same scan data. OBJECTIVES: We sought to evaluate the accuracy of noncontrast CT-derived LV size (LVS; sum of LV volume and mass) compared with magnetic resonance imaging (MRI)-derived measures as the clinical reference standard. METHODS: Participants (n = 5004) in the Multi-Ethnic Study of Atherosclerosis (MESA) who underwent cardiac MRI studies from August 2000 to September 2002 were included. CT-derived LVS was defined as the sum of LV mass and LV intracavitary volume. The calculated LVS was taken from a measurement of a single slice from noncontrast images. Multivariate analysis adjusting for demographics was used to identify predictors of the relation between CT LVS and MRI LVS, and Bland-Altman analysis was performed comparing MRI-derived measures with CT-derived measure of LVS. RESULTS: The mean CT LVS was 187.8 +/- 56.8 mL (range, 33.6-486.4 mL). The correlation was 0.73 (P = 0.01) for MRI-derived LV volume and 0.74 (P = 0.01) for MRI-derived LV mass. The correlation between CT LVS and MRI-derived LV end-diastolic total volume (mass + volume) was 0.79. CONCLUSION: A single NCE-CT scan used to detect and quantify coronary calcification can also estimate LVS with reasonable accuracy compared with MRI. This provides a new method to study ventricular size in epidemiologic studies and potentially provide additional information for clinical screening of cardiac risk.

Bahrami H, Kronmal R, Bluemke DA, Olson J, Shea S, Liu K, Burke GL, Lima JA. · Division of Cardiology, Department of Medicine, The Johns Hopkins University, Baltimore, MD 21287, USA. · Arch Intern Med. · Pubmed #18955644 No free full text.

Abstract: BACKGROUND: The relationship between incident congestive heart failure (CHF) and ethnicity as well as racial/ethnic differences in the mechanisms leading to CHF have not been demonstrated in a multiracial, population-based study. Our objective was to evaluate the relationship between race/ethnicity and incident CHF. METHODS: The Multi-Ethnic Study of Atherosclerosis (MESA) is a cohort study of 6814 participants of 4 ethnicities: white (38.5%), African American (27.8%), Hispanic (21.9%), and Chinese American (11.8%). Participants with a history of cardiovascular disease at baseline were excluded. Cox proportional hazards models were used for data analysis. RESULTS: During a median follow-up of 4.0 years, 79 participants developed CHF (incidence rate: 3.1 per 1000 person-years). African Americans had the highest incidence rate of CHF, followed by Hispanic, white, and Chinese American participants (incidence rates: 4.6, 3.5, 2.4, and 1.0 per 1000 person-years, respectively). Although risk of developing CHF was higher among African American compared with white participants (hazard ratio, 1.8; 95% confidence interval, 1.1-3.1), adding hypertension and/or diabetes mellitus to models including ethnicity eliminated statistical ethnic differences in incident CHF. Moreover, African Americans had the highest proportion of incident CHF not preceded by clinical myocardial infarction (75%) compared with other ethnic groups (P = .06). CONCLUSIONS: The higher risk of incident CHF among African Americans was related to differences in the prevalence of hypertension and diabetes mellitus as well as socioeconomic status. The mechanisms of CHF also differed by ethnicity; interim myocardial infarction had the least influence among African Americans, and left ventricular mass increase had the greatest effect among Hispanic and white participants.

Macedo R, Chen S, Lai S, Shea S, Malayeri AA, Szklo M, Lima JA, Bluemke DA. · Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA. · J Magn Reson Imaging. · Pubmed #18837001 No free full text.

Abstract: PURPOSE: To evaluate the use of coronary wall MRI as a measure of atherosclerotic disease burden in an asymptomatic population free of clinical cardiovascular disease. Coronary wall magnetic resonance imaging (MRI) is a noninvasive method for evaluation of arterial wall remodeling associated with atherosclerosis. MATERIALS AND METHODS: Asymptomatic participants of the Multi-Ethnic Study of Atherosclerosis (MESA) study were studied using black blood MRI. MRI-assessed coronary wall thickness was compared with computed tomography calcium score, carotid intimal-medial thickness, and risk factors for coronary artery disease. RESULTS: Eighty-eight arterial segments were evaluated in 38 MESA participants (mean age, 61.3+/-8.7 years). The maximum coronary wall thickness was greater for participants with two or more cardiovascular risk factors than for those with one or no risk factors (2.59+/-0.33 mm vs. 2.36+/-0.30 mm, respectively, P=0.05.) For participants with zero calcium score, the mean and maximum coronary wall thickness for subjects with two or more risk factors for coronary artery disease were greater than the wall thickness for subjects with one or no risk factors (mean thickness: 1.95+/-0.17 mm vs. 1.7+/-0.19 mm; maximum thickness: 2.67+/-0.24 mm vs. 2.32+/-0.27 mm, respectively, P<0.05). Subjects with increased carotid intimal-medial thickness also had increased coronary artery wall thickness (P<0.05). CONCLUSION: Coronary artery wall MRI detects increased coronary wall thickness in asymptomatic individuals with subclinical markers of atherosclerotic disease and in individuals with zero calcium score.

Brown ER, Kronmal RA, Bluemke DA, Guerci AD, Carr JJ, Goldin J, Detrano R. · Department of Biostatistics, University of Washington, F-600 Health Sciences Bldg, 1705 NE Pacific St, Seattle, WA 98195-7232, USA. · Radiology. · Pubmed #18413889 links to  free full text

Abstract: PURPOSE: To develop a new calcium score for use with unenhanced cardiac computed tomography (CT) that can be used to define the percentage of coronary arteries affected by calcium and to correlate this score with risk factors and cardiovascular events. MATERIALS AND METHODS: Institutional review boards at all participating centers approved this HIPAA-compliant study, and all participants gave written informed consent. Calcium coverage score (CCS), which represents the percentage of coronary arteries affected by calcific plaque, was calculated for 3252 participants in the Multi-Ethnic Study of Atherosclerosis in whom calcific plaque was detected with CT. Quasi-Poisson models were used to estimate associations (assessed by using t tests with robust standard errors) between CCS and risk factors. Associations between the CCS, Agatston, and calcium mass scores (hereafter, mass scores) and outcomes were estimated and assessed by using Cox proportional hazards models with Wald tests. The predictive ability of these models was assessed by using area under the receiver operating characteristic curves and bootstrap t tests. RESULTS: After adjustments were made for age, race, ethnicity, and sex in the quasi-Poisson model, CCS was associated with hypertension, dyslipidemia, and diabetes (P < .001 for all diseases). After adjustments for age and sex, a twofold increase in CCS was associated with a 52% (95% confidence interval: 34%, 72%) increase in risk for any coronary heart disease (CHD) event. When Agatston or mass scores were included with CCS in a Cox model for prediction of CHD events, neither Agatston score nor mass score was a significant predictor, whereas CCS remained significantly associated with CHD events. Although receiver operating characteristic curves suggested that there was a difference between CCS score and Agatston and mass scores in prediction of a cardiac event, no differences in prediction of hard cardiac events (myocardial infarction, death) were found. CONCLUSION: Both spatial distribution and amount of calcified plaque contribute to risk for CHD.

Detrano R, Guerci AD, Carr JJ, Bild DE, Burke G, Folsom AR, Liu K, Shea S, Szklo M, Bluemke DA, O'Leary DH, Tracy R, Watson K, Wong ND, Kronmal RA. · Department of Radiological Sciences, University of California at Irvine, Irvine, CA 92697, USA. · N Engl J Med. · Pubmed #18367736 links to  free full text

Abstract: BACKGROUND: In white populations, computed tomographic measurements of coronary-artery calcium predict coronary heart disease independently of traditional coronary risk factors. However, it is not known whether coronary-artery calcium predicts coronary heart disease in other racial or ethnic groups. METHODS: We collected data on risk factors and performed scanning for coronary calcium in a population-based sample of 6722 men and women, of whom 38.6% were white, 27.6% were black, 21.9% were Hispanic, and 11.9% were Chinese. The study subjects had no clinical cardiovascular disease at entry and were followed for a median of 3.8 years. RESULTS: There were 162 coronary events, of which 89 were major events (myocardial infarction or death from coronary heart disease). In comparison with participants with no coronary calcium, the adjusted risk of a coronary event was increased by a factor of 7.73 among participants with coronary calcium scores between 101 and 300 and by a factor of 9.67 among participants with scores above 300 (P<0.001 for both comparisons). Among the four racial and ethnic groups, a doubling of the calcium score increased the risk of a major coronary event by 15 to 35% and the risk of any coronary event by 18 to 39%. The areas under the receiver-operating-characteristic curves for the prediction of both major coronary events and any coronary event were higher when the calcium score was added to the standard risk factors. CONCLUSIONS: The coronary calcium score is a strong predictor of incident coronary heart disease and provides predictive information beyond that provided by standard risk factors in four major racial and ethnic groups in the United States. No major differences among racial and ethnic groups in the predictive value of calcium scores were detected.

Wasserman BA, Sharrett AR, Lai S, Gomes AS, Cushman M, Folsom AR, Bild DE, Kronmal RA, Sinha S, Bluemke DA. · The Russell H. Morgan Department of Radiology and Radiological Sciences, The Johns Hopkins Hospital, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. · Stroke. · Pubmed #18174475 links to  free full text

Abstract: BACKGROUND AND PURPOSE: Atheroma vulnerability to rupture is increased in the presence of a large lipid core. Factors associated with a lipid core in the general population have not been studied. METHODS: The Multi-Ethnic Study of Atherosclerosis (MESA) is a multicenter cohort study of individuals free of clinical cardiovascular disease designed to include a high proportion of ethnic minorities. We selected MESA participants from the top 15th percentile of maximum carotid intima media thickness by ultrasound and acquired high-resolution black blood MRI images through their carotid plaque before and after the intravenous administration of gadodiamide (0.1 mmol/kg). Lumen and outer wall contours were defined using semiautomated analysis software. We analyzed only plaques with a maximum thickness >or=1.5 mm by MRI (n=214) and assessed cross-sectional risk factor associations with lipid core presence by multivariable logistic regression. RESULTS: A lipid core was present in 151 (71%) of the plaques. After controlling for age, ethnicity, sex, maximum arterial wall thickness, hypertension, cigarette smoking, diabetes, and C-reactive protein, compared with participants in the lowest tertile of total plasma cholesterol, the ORs of having a lipid core for participants in the middle and highest tertiles were 2.76 (95% CI: 1.01 to 7.51) and 4.63 (95% CI: 1.56 to 13.75), respectively. None of the other risk factors was associated with lipid core. CONCLUSIONS: In persons with thickened carotid walls, plasma total cholesterol, but not other established coronary heart disease risk factors, is strongly associated with lipid core presence by MRI. High total cholesterol may be associated with rupture proneness of atherosclerotic lesions in the general population.

George RT, Jerosch-Herold M, Silva C, Kitagawa K, Bluemke DA, Lima JA, Lardo AC. · Department of Medicine, Division of Cardiology, Image Guided Cardiotherapy Laboratory, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA. · Invest Radiol. · Pubmed #18007153 No free full text.

Abstract: OBJECTIVES: The purpose of this study was to determine the ability of dynamic 64 slice multidetector computed tomography (d-MDCT) to provide an accurate measurement of myocardial blood flow (MBF) during first-pass d-MDCT using semiquantitative and quantitative analysis methods. MATERIALS AND METHODS: Six dogs with a moderate to severe left-anterior descending artery stenosis underwent adenosine (0.14 mL . kg-1 . min-1) stress d-MDCT imaging according to the following imaging protocol: iopamidol 10 mL/s for 3 seconds, 8 mm x 4 collimation, 400 milliseconds gantry rotation time, 120 kV, and 60 mAs. Images were reconstructed at 1-second intervals. Regions of interest were drawn in the LAD and remote territories, and time-attenuation curves were constructed. Myocardial perfusion was analyzed using a model-based deconvolution method and 2 upslope methods and compared with the microsphere MBF measurements. RESULTS: The myocardial upslope-to-LV-upslope and myocardial upslope-to-LV-max ratio strongly correlated with MBF (R2 = 0.92, P < 0.0001 and R2 = 0.87, P < 0.0001, respectively). Absolute MBF derived by model-based deconvolution analysis modestly overestimated MBF compared with microsphere MBF (3.0 +/- 2.5 mL . g-1 . min-1 vs. 2.6 +/- 2.7 mL . g-1 . min-1, respectively). Overall, MDCT-derived MBF strongly correlated with microspheres (R = 0.91, P < 0.0001, mean difference: 0.45 mL . g-1 . min-1, P = NS). CONCLUSIONS: d-MDCT MBF measurements using upslope and model-based deconvolution methods correlate well with microsphere MBF. These methods may become clinically applicable in conjunction with coronary angiography and next generation MDCT scanners with larger detector arrays and full cardiac coverage.

Vogel-Claussen J, Fishman EK, Bluemke DA. · Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD, USA. · Expert Rev Cardiovasc Ther. · Pubmed #17605656 No free full text.

Abstract: New developments in cardiac MRI and multidetector CT (MDCT) have generated tremendous excitement for both physicians and the general public. Their roles in the diagnostic algorithm of patients with suspected coronary artery disease are rapidly evolving. In addition to cardiac catheterization, nuclear imaging techniques and cardiac echocardiography, MDCT and MRI will play increasing roles in the diagnosis of ischemic heart disease. In this review we outline imaging techniques and illustrate the various applications of cardiac MRI and MDCT in the assessment of myocardial ischemia.

Cheung N, Bluemke DA, Klein R, Sharrett AR, Islam FM, Cotch MF, Klein BE, Criqui MH, Wong TY. · Centre for Eye Research Australia, University of Melbourne, Victoria, Australia. · J Am Coll Cardiol. · Pubmed #17601545 No free full text.

Abstract: OBJECTIVES: This study sought to examine the relationships of retinal vascular signs with left ventricular (LV) mass, volume, and concentric remodeling. BACKGROUND: Microvascular disease, reflected as retinopathy lesions, has been shown to predict clinical congestive heart failure. Whether these retinal vascular changes are related to early structural alterations and remodeling of the heart in asymptomatic individuals is unknown. METHODS: A cross-sectional, population-based study of 4,593 participants ages 45 to 85 years, free of clinical cardiovascular disease. Retinal vascular calibers and retinopathy were graded from retinal photographs according to standardized protocols. The LV mass and volume were measured from cardiac magnetic resonance imaging. Extent of LV concentric remodeling was determined by the ratio of LV mass to end-diastolic volume (M/V ratio). RESULTS: After controlling for age, gender, race, center, past and current systolic blood pressure, body mass index, smoking, antihypertensive medications, diabetes, diabetes duration, glycosylated hemoglobin, lipid profile, and C-reactive protein, narrower retinal arteriolar caliber was associated with concentric (highest quintile of M/V ratio) remodeling (odds ratio [OR] 2.06, 95% confidence interval 1.57 to 2.70). This association was seen in men and women, and was present even in those without diabetes, without hypertension, and without significant coronary calcification. In multivariate analysis, the presence of retinopathy (OR 1.31, 95% confidence interval 1.08 to 1.61) was also associated with concentric remodeling. CONCLUSIONS: Narrower retinal arteriolar caliber is associated with LV concentric remodeling independent of traditional risk factors and coronary atherosclerotic burden, supporting the hypothesis that microvascular disease may contribute to cardiac remodeling.

Nasir K, Rosen BD, Kramer HJ, Edvardsen T, Bluemke DA, Liu K, Lima JA. · Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA. · Am Heart J. · Pubmed #17383292 No free full text.

Abstract: INTRODUCTION: Asymptomatic individuals with moderate reduction in renal function are at increased risk for congestive heart failure. In this study we investigate the relationship between mild-moderate renal insufficiency and regional left ventricle function in a population free of cardiovascular disease. METHOD: This is a cross-sectional study in 500 individuals > or = 45 years of age without known cardiovascular disease who participated in the Multi-Ethnic Study of Atherosclerosis. Regional systolic and diastolic strain rate as well as peak systolic midwall circumferential strain were calculated from tagged magnetic resonance imaging studies in these participants. Regions were defined by coronary territories (left anterior descending, left circumflex, right coronary artery). Creatinine clearance (CrCl) was estimated by using the Cockcroft-Gault equation and categorized as > or = 90 mL/min (normal CrCl), 60 to 89 mL/min (mildly reduced CrCl), and < 60 mL/min (moderately reduced CrCl). RESULTS: The mean participant age was 66 +/- 10 years (58% men). The mean CrCl was 80 +/- 25 mL/min. Multiple linear regression analyses indicated that circumferential systolic strain as well as systolic strain rate were significantly lower in participants with moderately reduced CrCl compared with those with normal CrCl in all coronary territories. Lower diastolic strain rates was observed in mild-moderate renal territories compared with those with normal CrCl. CONCLUSIONS: Impaired regional systolic and diastolic function was observed with mild-moderate reduction of renal function without evidence of clinical heart disease. The results strengthen the usefulness of routine determination of renal function in potentially identify individuals with early myocardial dysfunction.

Silber HA, Lima JA, Bluemke DA, Astor BC, Gupta SN, Foo TK, Ouyang P. · Department of Medicine, Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. · J Am Coll Cardiol. · Pubmed #17336716 No free full text.

Abstract: OBJECTIVES: Our goal was to investigate whether the association between established cardiovascular risk factors and arterial reactivity differs between the lower and upper extremities. BACKGROUND: Resistance artery reactivity in the arm is associated with cardiovascular risk factors, coronary disease, and events. However, the relationship of lower versus upper extremity vasoreactivity to increasing cardiovascular risk factors has not been determined. METHODS: We studied 82 subjects in 3 groups: 33 young healthy (YH) (21 to 41 years), 30 older healthy (OH) (>50 years), and 19 older type 2 diabetic subjects (OD). We directly measured systolic shear rate, flow, and radius in brachial and femoral arteries at rest and during post-occlusion hyperemia using magnetic resonance imaging. RESULTS: Brachial and femoral systolic shear rate, flow, and radius were similar among the groups at rest. Brachial hyperemic shear rate and hyperemic flow normalized as a function of baseline radius were not statistically different when YH were compared with OH and OH with OD. In contrast, femoral hyperemic shear rate and hyperemic flow normalized to baseline radius were lower in OH than YH (680 +/- 236 s(-1) vs. 843 +/- 157 s(-1), p = 0.001, and 0.84 +/- 0.25 mm(1.27)/s vs. 1.01 +/- 0.16 mm(1.27)/s, p = 0.001) and lower in OD than OH (549 +/- 183 s(-1), p = 0.02, and 0.74 +/- 0.19 mm(1.27)/s, p = 0.046). CONCLUSIONS: Persons with increasing cardiovascular risk factor burden had progressively reduced arterial reactivity in lower but not upper extremities. This may help to explain why atherosclerosis usually develops more severely in legs than in arms, and suggests that legs may be more sensitive than arms for assessing early global atherosclerotic risk.