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ABSTRACT: Background: Atherosclerotic calcification is a risk factor for cardiovascular events, independent of other traditional risk factors. Studies of the relation of menopausal hormone therapy to cardiovascular events have had inconsistent results, and often have been confounded by lifestyle behaviors and the "healthy user" effect. The authors evaluated the cross-sectional association of hormone therapy use with the presence and severity of atherosclerosis in postmenopausal women, independent of lifestyle factors, including diet and physical activity levels. Methods: The authors consecutively enrolled postmenopausal asymptomatic women who were referred for coronary artery calcium scanning to measure cardiovascular risk. After consent was obtained, women were interviewed prior to their cardiac scan about cardiac risk factors, hormone therapy use, menopausal status, diet, and physical activity. Coronary artery calcium prevalence was defined as any calcification present (score >0). Results: Of the 544 enrolled women aged 50-80 years, 252 (46.3%) were hormone therapy users. Hormone therapy users had a significantly lower prevalence of any coronary artery calcium (defined as coronary artery calcium score >0; 37%), than non-users (50%, p = 0.04), as well as significantly lower mean calcium scores (p = 0.02). Multiple logistic regression models demonstrated a significantly reduced odds of coronary artery calcium in hormone therapy users compared to non-users with an adjusted odds ratio of 0.58 (p = 0.04), adjusting for traditional cardiac risk factors and body mass index. Women who reported consuming a vegetarian or a high-protein diet had almost two-fold odds of coronary artery calcium compared with women who reported regular, mixed, or low-fat, low-salt diets (OR = 1.78, p = 0.02). Severity of coronary artery calcium was less with increasing levels of physical activity, and a significant association was observed between physical activity and hormone therapy use (adjusted OR = 4.05, p = 0.03), independent of coronary artery calcium severity. Conclusion: This cross-sectional study demonstrated a protective association of hormone therapy with the presence and severity of coronary artery calcium. Although a strong relationship was observed between hormone therapy and physical activity, their complex interplay may affect mechanistic biochemical and physiological processes that have yet to be clearly delineated. Thus, physical activity and diet should be taken into account in prospective studies of the relation of hormone therapy use to coronary artery calcium.
Women & Health 07/2012; 52(5):423-36. · 1.00 Impact Factor
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ABSTRACT: To create standard thoracic bone mineral density (BMD) values for patients undergoing cardiac computed tomography (CT) by using thoracic quantitative CT and to compare these BMDs (in a subpopulation) with those obtained by using lumbar spine quantitative CT.
The institutional review board approved this HIPAA-compliant study. A total of 9585 asymptomatic subjects (mean age, 56 years; age range, 30-90 years) who underwent coronary artery calcium scanning, including 4131 women, were examined. Patients with vertebral deformities or fractures were excluded. Six hundred forty-four subjects (322 of whom were female) also underwent lumbar quantitative CT. The mean thoracic vertebral BMDs for both sexes were reported separately in a subgroup of subjects aged 30 years and in 29 age-based subgroups in 2-year intervals from ages 30 to 90 years. The formulas used to calculate the female T score (T(f)) and the male T score (T(m)) on the basis of thoracic quantitative CT measurements were as follows: T(f) = (BMD(im) - 222)/36, and T(m) = (BMD(im) - 215)/33, where BMD(im) is the individual mean BMD. Comparisons between thoracic quantitative CT and lumbar quantitative CT measurements, as well as analyses of intraobserver, interobserver, and interscan variability, were performed.
The young-subgroup mean BMD was 221.9 mg/mL ± 36.2 (standard deviation) for the female subjects and 215.2 mg/mL ± 33.2 for the male subjects. The mean thoracic BMDs for the female and male subjects were found to be 20.7% higher and 17.0% higher, respectively, than the values measured with lumbar quantitative CT (P < .001 for both comparisons). A significant positive association between the thoracic and lumbar quantitative CT measurements (r > 0.85, P < .001) was found. Intraobserver, interobserver, and interscan variabilities in thoracic quantitative CT measurements were 2.5%, 2.6%, and 2.8%, respectively.
There was a significant association between the mean thoracic and lumbar BMDs. Therefore, standard derived measurements (young-subgroup BMD ± standard deviation) based on these data can be used with thoracic CT images to estimate the bone mineral status.
Radiology 11/2010; 257(2):434-40. · 5.73 Impact Factor
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ABSTRACT: Few studies have been published describing the association of coronary plaques and coronary artery calcium (CAC) to left ventricular (LV) mass and LV function using multi-detector computed tomography (MDCT). Coronary plaques can potentially influence the LV function. We sought to evaluate LV mass and function on MDCT and its correlation with CAC and plaque burden in the coronary arteries.
We included 197 symptomatic patients from the multicenter ACCURACY Study. The LV mass was measured manually using Advantage 4.4 workstation. Interobserver variability of LV mass was assessed using 34 randomly selected studies. LV mass was indexed to the body surface area. The coronary plaque severity was assessed in each segment using MDCT, following the 15 segment American Heart Association model. Plaque and segment scores were calculated accordingly. Statistical analysis using multiple logistic regression analysis was performed.
We divided the cohort into those with CAC=0 [n=67 (34%)] and those with CAC greater than 0 [n=130 (66%)]. A significant correlation was found between indexed LV mass and CAC, plaque, and segment scores in both adjusted and unadjusted models. A significant association was observed between nonindexed LV mass with CAC, MDCT plaque score and segment score upon adjusting for various cardiovascular risk factors. A significant correlation was found between hyperlipidemia, hypertension, family history of CAD, and greater than 50% and greater than 70% stenosis on invasive cardiac catheterization with LV mass (all P<0.05).
To our knowledge, this is the first study evaluating coronary plaque on computed tomographic angiography with LV mass. We were able to show a significant correlation of LV mass with CAC score, and with total plaque and total segment scores. The poor prognosis associated with increased CAC scores may be partially explained by this association with increased LV mass.
Coronary artery disease 11/2010; 21(7):428-34. · 1.56 Impact Factor
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ABSTRACT: Cardiovascular computed tomographic angiography (CTA) can visualize the coronary veins. We sought to assess the ability of CTA to facilitate resynchronization therapy (CRT) procedures using a prospective randomized single-center pilot study.
Patients underwent CTA for characterization of cardiomyopathy prior to biventricular implantable cardiac-defibrillator implant. Randomization was performed with operator review of the CTA for coronary venous anatomy prior to CRT in one-half of the cases. Invasive coronary venous angiograms were used in all procedures. Analysis included procedure times and utilization of contrast, fluoroscopy, and guide catheters.
Characteristics of the 26 patients enrolled were mean age 55 ± 11 years, male 76.9%, ischemic etiology 35%, ejection fraction 25 ± 3%, class III congestive heart failure 100%, and QRS duration 179 ± 29 ms. Of patients enrolled, 22 had both CTA and procedure initiation. Three patients (two with CTA review and one without CTA review) had aborted procedures due to hemodynamic issues. Analysis of the 22 patients (nine with preprocedure CTA review and 13 without CTA review) demonstrated that preprocedure review of CTA coronary venous anatomy led to significantly decreased procedure times and utilization of contrast, fluoroscopy, and guide catheters.
Preprocedure review of CTA coronary venous anatomy may lead to decreased procedural times and utilization of contrast, fluoroscopy, and guide catheters. These preliminary results will need to be evaluated in larger heart failure populations undergoing CRT.
Pacing and Clinical Electrophysiology 10/2010; 33(10):1182-7. · 1.35 Impact Factor
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ABSTRACT: Coronary artery calcium is a sensitive risk predictor of cardiac events. However, measurement of calcium foci is affected by partial-volume effects, which ultimately have an effect on accuracy and reproducibility of calcium scores. In this study, we describe the accuracy of quantification of calcium foci of known size and density using cork-dog heart phantoms.
Five study phantoms were constructed from cork chests and dog hearts containing 135 calcium hydroxyapatite (CaHA) foci of known volume, mass, and concentration located in the coronary arteries or the myocardium. Hearts were separated into two groups: (1) three hearts containing large, high-density foci and (2) two hearts containing small, low-density foci. The phantoms were scanned using a standard coronary artery calcium (CAC) protocol and the volume and mean intensity of foci were measured.
In group 1, the total volume of 87 CaHA foci measured was 4284 and 3779 mm(3) with electron beam computed tomography (EBCT); multidetector computed tomography (MDCT), respectively (P < .001). Both were significantly larger than the true volume (2713.9 mm(3), P < .001). In Group 2, the total volume of 57 CaHA foci measured was 592.6 and 702.9 mm(3) with EBT and MDCT, respectively (P < .001). Both were significantly smaller than the true volume (1733.2 mm(3), P < .001). We found that EBCT values for volume were approximately generally higher than MDCT values, but strongly correlated (r = 0.95, P < .0001). Agatston scores were found to be nearly equivalent between EBCT and MDCT and were similarly strongly correlated (r = 0.97, P < .0001).
Computed tomography images overestimate the volume of large, dense CaHA foci while underestimating the volume of smaller (<6.6 mm(3)), less dense foci. This may have significant implications on CAC scoring and volume measurement. EBCT overestimated calcium more than MDCT, most likely from increased image noise.
Academic radiology 10/2010; 17(10):1249-53. · 2.09 Impact Factor
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02/2009: pages 1-14;
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ABSTRACT: Inflammation is related to many stages of atherosclerosis, and inflammatory markers have been associated with both atherosclerosis and future cardiovascular events. Descending thoracic aortic calcification (DTAC) is a manifestation of atherosclerosis, however, no previous study has examined the relationship of inflammatory markers and DTAC as detected by computed tomography (CT) in a large study. We examined whether C-reactive protein (CRP) and interleukin-6 (IL-6) are independently associated with DTAC.
The Multi-Ethnic Study of Atherosclerosis (MESA) is a prospective cohort study that includes 6814 women and men ages 45-84 years old, all free of baseline cardiovascular disease. The inflammation markers CRP and IL-6, and DTAC by CT, quantified by Agatston score, were measured at baseline in all participants.
We studied 6613 participants with complete data (3112 men, 3501 women, mean age 62+/-10 years). The prevalence of DTAC was 27%. Participants with DTAC had significantly higher levels of both CRP and IL-6. After adjustment for baseline risk factors, CRP was not correlated with presence or severity of DTAC (Adjusted RR per S.D., 1.01; 95% confidence intervals 0.97; 1.05) while IL-6 associations remained significant (adjusted RR per S.D., 1.07; 95% confidence intervals 1.02; 1.14).
IL-6, a systemic inflammatory marker, is related to the presence and extent of DTAC. Further studies are needed to evaluate the interaction between DTAC and inflammation markers as predictors of future cardiovascular events.
Atherosclerosis 08/2008; 199(1):201-6. · 3.79 Impact Factor
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ABSTRACT: Although cardiovascular risk factor levels are substantially different in Caucasians, African-American, Hispanics, and Asians, the relative rates of coronary heart disease in these groups are not consistent with these differences. The objective of the study is to assess the differences in the prevalence and severity of coronary artery calcification, as a measure of atherosclerosis, in these different ethnic groups.
Electron-beam tomography was performed in 16,560 asymptomatic men and women (Asians=1336, African-Americans=610, Hispanics=1256) aged >or=35 years referred by their physician for cardiovascular risk evaluation. The study population encompassed 70% males, aged 52+/-8 years.
Caucasians were more likely to present with dyslipidemia (p<0.0001), while African-Americans and Hispanics had a higher prevalence of smoking, diabetes, and hypertension (all p<0.001). After adjustment for age, gender, risk factors, and treatment for hypercholesterolemia, compared with Caucasians, the relative risks for men having coronary calcification were 0.64 (95% CI: 0.48-0.86) in African-Americans, 0.88 (95% CI: 0.67-1.15) in Hispanics, and 0.66 (95% CI: 0.55-0.80) in Asians. After similar adjustments, the relative risks for women having coronary calcification, were 1.58 (95% CI: 1.13-2.19) for African-Americans, 0.84 (95% CI: 0.66-1.06) in Hispanics, and 0.71 (95% CI: 0.56-0.89) in Asian women. After adjusting for age and risk factors using multivariable analysis, African-American men were least likely to have any coronary calcium while African-American women had significantly higher OR of any calcification. Asian men and women had significantly lower OR of any calcification. There was no significant difference in prevalence or severity of atherosclerosis between Hispanics and Caucasians, in men or women.
Our study results demonstrate significant difference in the presence as well as severity of calcification according to ethnicity, independent of atherosclerotic risk factors. Results from this study (physician referred) closely parallel the results from MESA (population based, measured risk factors). Ethnic specific data on the predictive value of differing coronary calcium scores are needed.
Atherosclerosis 09/2006; 187(2):343-50. · 3.79 Impact Factor
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ABSTRACT: The detection of coronary artery calcification (CAC) using the electron beam tomography (EBT) scanner provides a noninvasive indicator for coronary artery disease (CAD). Physicians interested in preventative medicine also are using this modality to track atherosclerosis over time. Two new iterations of the EBT scanner have been introduced. We sought to evaluate the image quality of each machine to examine whether patients scanned on a previous model would have similar image quality and results to those scanned on the newest scanner.
This study used the C-150 XP, C300, and the e-Speed EBT scanners in high-resolution volume mode. A cork chest phantom was constructed for use as a human chest. A mixture of calcium phosphate, cornstarch and glue was placed inside the wells to simulate coronary calcium. The foci masses were 3, 5, 7, 10, 15, 20, 40, 60, 80, 100, and 200 mg (calcium mass), which provided the 55 foci of different masses and densities to simulate coronary calcium in the chest phantom. Each phantom was scanned multiple times, using both 1.5- and 3-mm slice thickness and table collimation settings with each scanner.
There were no statistical differences found between the 1.5-mm and 3.0-mm slice thickness calcium foci scores (Agatston & volumetric) for all 3 EBT scanners. The C-150 XP scanner had a variability of 6.01% between 1.5-mm and 3.0-mm slice thickness. Analysis by t test revealed that the mean noise value of C-150 XP was significantly higher than the C300, e-Speed (50 milliseconds), and e-Speed (100 milliseconds) with P values of 0.001, 0.025, and 0.001, respectively. Comparison of 1.5-mm versus 3.0-mm slice thickness noise value showed a significant difference only for the C-150 XP scanner (P < 0.05).
The use of the 3 EBT scanners in longitudinal studies of patients coronary calcium score is feasible to obtain similar calcium score values. The C-150 XP has the greatest noise effect in comparison to the C300 and e-Speed scanners. Improved image noise should improve reproducibility of the calcium measurement with these newer devices.
Investigative Radiology 07/2006; 41(6):522-6. · 4.59 Impact Factor
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ABSTRACT: To evaluate the effect of scanner collimation on the ability to detect small cardiac vessels using electron beam CT coronary angiography (EBA).
EBA scans from 40 patients who underwent study on two separate occasions with 3 mm (initial scan) and 1.5 mm (follow-up scan) collimation protocols were analyzed. Vessels of <2 mm in diameter were identified.
The 1.5 mm collimation allowed 3-D visualization of 129 vessels<2 mm in diameter, while 3 mm collimation only allowed visualization of 89 vessels (p<0.001). The right coronary artery branches and distal LAD segments though were not displayed satisfactorily in almost half of the 3-D studies with either protocol.
There was significant improvement in detection of small cardiac vessels with a 1.5 mm collimation EBA protocol compared to a 3 mm protocol. Both protocols though were insufficient for reliable visualization of the right coronary artery branches and distal LAD segments.
The International Journal of Cardiovascular Imaging 04/2006; 22(2):275-82. · 2.29 Impact Factor
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ABSTRACT: Electron beam angiography is a minimally invasive imaging technique. Adequate vascular opacification throughout the study remains a critical issue for image quality. We hypothesized that vascular image opacification and uniformity of vascular enhancement between slices can be improved using multiphase contrast medium injection protocols.
We enrolled 244 consecutive patients who were randomized to three different injection protocols: single-phase contrast medium injection (Group 1), dual-phase contrast medium injection with each phase at a different injection rate (Group 2), and a three-phase injection with two phases of contrast medium injection followed by a saline injection phase (Group 3). Parameters measured were aortic opacification based on Hounsfield units and uniformity of aortic enhancement at predetermined slices (locations from top [level 1] to base [level 60]).
In Group 1, contrast opacification differed across seven predetermined locations (scan levels: 1st versus 60th, P < .05), demonstrating significant nonuniformity. In Group 2, there was more uniform vascular enhancement, with no significant differences between the first 50 slices (P > .05). In Group 3, there was greater uniformity of vascular enhancement and higher mean Hounsfield units value across all 60 images, from the aortic root to the base of the heart (P < .05).
The three-phase injection protocol improved vascular opacification at the base of the heart, as well as uniformity of arterial enhancement throughout the study.
Academic Radiology 03/2006; 13(2):159-65. · 1.69 Impact Factor
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ABSTRACT: Extracoronary calcifications may have clinical significance. The error in extracoronary calcification measurements is still unknown. Accurate quantification of calcifications of the aortic valve (AVC), mitral annulus (MAC), and aortic wall (AWC) may be possible by using cardiac computed tomography (CT). We sought to establish the interscan, interobserver, and intraobserver reproducibility of these measures in all cardiac CT scans in the Multi-Ethnic Study of Atherosclerosis.
We measured extracoronary calcifications in 100 randomly selected participants to assess interobserver, interscan, and intraobserver variability. Two scans were available for analysis in 99 of these participants, and we quantified thoracic aorta and valvular calcifications.
Mean interscan variability of AVC was 9.7% +/- 11.4% and 8% +/- 10.3% for Agatston and volume scores, with variability of the median at 6.4% and 5.5%, respectively (P > .05). MAC inter-reader variability was 8.2% and 8.9%, with interscan variability of 28% and 33% and intrareader variability of 4% and 4.1%, respectively. For AWC, inter-reader variability was 3%-7.1%, interscan variability was 17%-18%, and intrareader variability was 0.4%-1.4%.
AVC, MAC, and AWC measurements are sufficiently reproducible to allow serial investigations over a time suitable for clinical studies.
Academic Radiology 03/2006; 13(2):166-72. · 1.69 Impact Factor
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ABSTRACT: The coronary venous system can provide vascular access for diagnostic and therapeutic procedures. Visualization of the coronary veins and their relationship to other cardiac structures may play an important role in facilitating these procedures. We sought to assess the ability of electron beam computed tomographic angiography (EBCTA) to characterize 3-dimensional (3-D) coronary venous anatomy.
Two hundred thirty-one consecutive EBCTA coronary studies were analyzed. The coronary venous system was mapped and analyzed using 2- and 3-D images with definition of diameter and angulations of branch vessels and distance from CS os.
The coronary sinus (CS), great cardiac, middle cardiac, left ventricular (LV) anterior interventricular, LV marginal, LV posterior, left atrial, and right atrial veins were visualized in 100%, 100%, 100%, 100%, 78%, 81%, 6%, and 8% of the studies, respectively, with definition of diameter and angulations of branch vessels and distance from CS os. There was a significant linear correlation between CS diameter and right atrial end systolic volume (R = 0.244, n = 81, P < .05). No significant correlation existed between CS os diameter and other cardiac size or function parameters. The 3-D spatial arrangements between the coronary veins and the coronary arteries in relation to the epicardium were able to be defined, on the basis of the vessel closer to the epicardium in overlapping segments.
EBCTA can provide 3-D visualization of most components of the coronary venous system and definition of the spatial relationships with coronary arteries. EBCTA may potentially serve as a useful noninvasive tool for coronary venous imaging for procedures involving coronary veins, such as resynchronization therapy.
American heart journal 08/2005; 150(2):315-22. · 4.65 Impact Factor
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ABSTRACT: The recent Women's Health Initiative (WHI) results have demonstrated that combined estrogen plus progestin imparts a small but significant increase in cardiovascular risk and breast cancer among asymptomatic women. However, the effect and potential benefit of unopposed estrogen is not as clear. We sought to evaluate the progression of subclinical atherosclerosis in postmenopausal women using no hormone replacement therapy (HRT), combined therapy, and estrogen alone in an observational study.
Postmenopausal women without symptoms or known coronary heart disease (CHD) were evaluated at our center for follow-up of coronary calcification. Patients were physician referred and underwent two consecutive electron beam tomography scans at least 1 year apart. All women fitting the study criteria were asked to participate, and those who consented were included. Demographic data, risk factors for CHD, HRT, and other medication use were collected by interview.
The study included 177 asymptomatic women. Calcium progression was 14.6%+/-21% in women taking any hormone therapy (n=97). Annual calcium progression rates in nonusers (n=80) was 22.3%+/-32%. Relative to the nonuser group, HRT treatment inhibited the progression of atherosclerosis by 35% (p=0.01). This effect was independent of age, risk, cardiovascular factors, statin use, or baseline CAC score. Thirty-five of the 97 women (36%) were taking estrogen plus progestin, with an annual increase in calcium scores of 24%+/-23%, similar to the non-HRT women (22%). Those women taking estrogen replacement only (n=62) was 63% lower (9%+/-22%).
This is an observational study, and the results are in accordance with the recently published WHI study, demonstrating no benefit of estrogen plus progestin compared with no therapy. However, women taking unopposed estrogen demonstrated a significant slowing of subclinical atherosclerosis compared with non-HRT and estrogen plus progestin.
Journal of Women s Health 07/2005; 14(5):410-7. · 1.57 Impact Factor
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Clinical Cardiology 03/2005; 28(2):100. · 2.15 Impact Factor
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ABSTRACT: The newest generation of electron beam tomographic scanner (e-Speed) has increased spatial and temporal resolution compared with the C-150 XP scanner. The aim of this study was to evaluate coronary artery calcium screening image quality between the e-Speed and C-150 scanners (GE Imatron, San Francisco, CA).
Studies from 41 patients (14 women and 27 men) who underwent serial coronary artery calcium screening with the C-150 (first study) and the e-Speed (second study) were analyzed. Individual computed tomography (CT) slices were assessed for coronary artery motion artifacts, and CT Hounsfield units (HU) and noise values (CT HU standard deviation) at 16 discrete cardiac sites were measured and averaged.
With the e-Speed scanner, there were significant decreases in right coronary artery motion artifacts compared with the C-150 scanner (0.3% versus 1.8%, P < .001) as well as decreased noise values (24.3 versus 32.0 HU, P < .001).
Image quality is significantly improved with use of the e-Speed scanner, due to its improved temporal and spatial resolution, compared with the C-150 scanner.
Academic Radiology 03/2005; 12(3):309-12. · 1.69 Impact Factor
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ABSTRACT: It has been demonstrated that aortic valve calcification (AVC) shares many similarities with coronary atherosclerosis, including risk factors and pathologic characteristics. We sought to examine the relationship of AVC to coronary artery calcification (CC), to assess whether similar risk factors affect the process in a similar way.
The study included 620 asymptomatic persons (513 men and 107 women, mean age 59 years range [30-82]) who underwent two consecutive electron beam tomography (EBT) scans at least 1 year apart (mean 3.3 years). Calcification scores were obtained by summation of Agatston and volumetric scores. Stabilization of calcium was defined as no increase in score per year or positive percent change in score </=1%/year. Progression was defined as a positive percent change in score >1%/year. Of 106 with AVC, 105 (99%) had CC. Sixty-five patients had an AVC >10 on initial scan, and 50 (77%) demonstrated progression on the follow-up scan. Of 394 participants with CC >10 on initial scan, follow-up scans showed CC stabilization in 64 (16.2%) and CC progression in 330 (83.8%). Patients with AVC were significantly older than those with only CC (64.5 versus 56.5 years, P < .0001). The average age of the patient with AVC was 7 years older than the average age with CC. AVC (by volumetric score) progressed more rapidly in patients with diabetes (P = .036) and smoking (P = .042) than those without.
We found no difference in the degree of change in the CC scores (by Agatston or volumetric methods) over time between men and women, or in any baseline cardiac risk factor (P > .05 for all measures). In 65 patients with both AVC and CC >10, there was a significant association between progression of AVC and CC (P = .047); the absolute rate of change of AVC was 24.5 +/- 43.2 %/year, and CC was 28.0 +/- 49.1 %/year.
Virtually all patients with AVC had CC, potentially explaining the coronary risk associated with AVC. There is substantially parallel development between rates of progression of EBT-assessed AVC and CC.
Academic Radiology 03/2005; 12(3):298-304. · 1.69 Impact Factor
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ABSTRACT: 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.
Eighty-six patients with suspected coronary disease were studied with EBA and conventional invasive coronary angiography. Electrocardiographic triggering was performed at a fixed time in end systole to reduce cardiac motion. Thin (1.5 mm) slices were obtained with 1.5 mm table incrementation. In axial (2-dimensional) EBA images and 3-dimensional reconstructions, all coronary arteries and side branches with a diameter of >or=1.5 mm were assessed for the presence of stenoses with >50% diameter reduction. Both EBA and invasive angiographic images were assessed in a blinded manner.
In comparison to invasive coronary angiography, EBA correctly classified 49 of 53 patients (92%) as having at least 1 coronary stenosis. Overall, 103 stenoses with >50% diameter reduction were present, and 93 of these lesions were correctly detected by EBA (sensitivity 90%, specificity 93%, positive predictive value 84%, and negative predictive value 96%). Only 5% of vessels could not be assessed, predominantly due to significant calcification.
Thinner slice collimation and end-systolic electrocardiographic triggering improves accuracy and assessment of coronary EBA for the detection of obstructive coronary artery disease, making this study clinically useful in the evaluation of obstructive coronary artery disease.
American heart journal 12/2004; 148(6):1085-90. · 4.65 Impact Factor
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ABSTRACT: We report visualization of a prominent coronary sinus os valve (Thebesian valve), by electron beam computed tomographic angiography, which impeded an endocardial approach to left ventricular pacing. Resynchronization therapy was therefore performed with an epicardial approach to left ventricular lead placement. Electron beam computed tomographic angiography can provide detailed information for coronary sinus instrumentation, including anomalies potentially affecting the approach to resynchronization therapy.
Pacing and Clinical Electrophysiology 12/2004; 27(11):1566-7. · 1.35 Impact Factor
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ABSTRACT: We report visualization of a prominent coronary sinus os valve (Thebesian valve), by electron beam computed tomographic angiography, which impeded an endocardial approach to left ventricular pacing. Resynchronization therapy was therefore performed with an epicardial approach to left ventricular lead placement. Electron beam computed tomographic angiography can provide detailed information for coronary sinus instrumentation, including anomalies potentially affecting the approach to resynchronization therapy.
Pacing and Clinical Electrophysiology 08/2004; 27(9):1331 - 1332. · 1.35 Impact Factor
