(Circulation. 2000;101:244.)
© 2000 American Heart Association, Inc.
Clinical Investigation and Reports |
Severity of Coronary Artery Calcification by Electron Beam Computed Tomography Predicts Silent Myocardial Ischemia
Presented in part at the 46th Annual Scientific Session, American College of Cardiology, Anaheim, Calif, March 19, 1997.
From the Cardiovascular Institute and Fu Wai Hospital, Peking Union Medical College, Beijing, China (Z.-X.H.); Baylor College of Medicine, Houston, Tex (T.D.H., C.M.P., M.S.V., R.R., J.J.M.); and North Houston Heart Center, Houston, Tex (V.A.).
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Abstract |
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 Top Abstract IntroductionMethodsResultsDiscussionReferences |
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Background—Detection of subclinical coronary artery disease (CAD) before the development of life-threatening cardiac complications has great potential clinical relevance. Electron beam computed tomography (EBCT) is currently the only noninvasive test that can detect CAD in all stages of its development and thus has the potential to be an excellent screening technique for identifying asymptomatic subjects with underlying myocardial ischemia.
Methods and Results—Over 2.5 years, we prospectively studied 3895
generally asymptomatic subjects with EBCT, 411 of whom had
stress myocardial perfusion tomography (SPECT) within a close (median,
17 days) time period. SPECT and exercise treadmill results were
compared with the coronary artery calcium score (CACS) as
assessed by EBCT. The total CACS identified a population at high risk
for having myocardial ischemia by SPECT although only a
minority of subjects (22%) with an abnormal EBCT had an abnormal
SPECT. No subject with CACS <10 had an abnormal SPECT compared with
2.6% of those with scores from 11 to 100, 11.3% of those with scores
from 101 to 399, and 46% of those with scores 
400
(P<0.0001). CACS predicted an abnormal SPECT regardless
of subject age or sex.
Conclusions—CACS identifies a high-risk group of asymptomatic subjects who have clinically important silent myocardial ischemia. Our results support the role of EBCT as the initial screening tool for identifying individuals at various stages of CAD development for whom therapeutic decision making may differ considerably.
Key Words: tomography • calcium • ischemia
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Introduction |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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The detection of subclinical coronary artery disease (CAD) before the development of life-threatening cardiac complications has great potential clinical relevance. However, currently available noninvasive techniques, such as exercise treadmill testing (ETT) and myocardial single photon emission computed tomography (SPECT), can identify only patients with advanced CAD who manifest myocardial ischemia.1 2 Although the presence and extent of left ventricular ischemia can accurately identify individuals at high risk for cardiac events,3 4 5 6 7 8 the low prevalence of a positive test result among asymptomatic subjects with cardiac risk factors mitigates against this approach.7 8 9
Electron beam computed tomography (EBCT) is a new noninvasive technique that can detect coronary atherosclerosis even at its earliest stages on the basis of the presence and severity of coronary artery calcification.10 Although calcification severity predicts the presence of significant anatomic CAD,11 12 there is little information as to whether the coronary artery calcium score (CACS) can identify asymptomatic individuals at high risk for having myocardial ischemia among a larger, asymptomatic, heterogeneous population with cardiac risk factors.12 This is clinically important because the presence and extent of left ventricular ischemia predict outcome beyond that provided by coronary angiographic findings alone.4 5 13
Accordingly, the purpose of this study was to determine whether EBCT could identify subjects with scintigraphic ischemia on the basis of CACS severity and thereby define its role as a primary screening technique for identifying subjects with a broad spectrum of CAD.
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Methods |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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Study Population
From December 1995 to May 1998, 3895 subjects had EBCT at our imaging center; 411 also had stress SPECT within a close temporal period (median, 17 days) to detect myocardial ischemia (Table 1
). Individuals who had an
abnormal EBCT were encouraged to have SPECT; however, we did not seek
to identify subjects who had SPECT at institutions other than our own.
Most of the 411 subjects (87%) were entirely asymptomatic
although 54 (13%) had various nonanginal chest pain symptoms. All
subjects had risk factors known to promote the development of CAD
(Table 1). The baseline characteristics of subjects with and
without a history of atypical chest pain were generally similar (Table 2).
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EBCT Study
EBCT was performed on an Imatron C-150 ultrafast CT scanner with
a 100-ms exposure time and 30-cm field size. With ECG gating, 32
consecutive images were obtained in diastole at 3-mm
intervals. Coronary calcification was defined as a lesion of
>130 Hounsfield units with an area >1.02 mm; lesions were
manually planimetered by an experienced technologist and reviewed by a
radiologist (T.D.H.). CACS was determined for the 4 main
coronary arteries and then summed to generate a total score.
The Agatston score was defined as normal, mild, moderate, or severe on
the basis of total CACS and subject age and sex.14 We also
performed analysis using a more recently proposed scoring
system based on the total CACS: 0 (normal), 1 to 10 (minimal), 11 to
100 (mild), 101 to 399 (moderate), and 400
(severe).15
SPECT Study
Standard stress and rest SPECT were performed with
201Tl (67%), 99mTc
sestamibi (21%), or tetrofosmin (12%).2 16
Symptom-limited ETT by use of the Bruce protocol was performed in 352
subjects (86%), whereas 11% received adenosine17
and 3% received dobutamine18 with standard
infusion protocols. ECG ischemia was defined as a 1-mm
ST-segment depression occurring 80 ms after the J point. All exercise
ECGs were interpreted by researchers who had no knowledge of EBCT or
SPECT results. We excluded 10 subjects because of lack of stress ECG
data (n=3), left ventricular hypertrophy (n=6),
or left bundle-branch block (n=1). A standard Duke treadmill score was
calculated in the remaining 342 subjects and defined as low (5),
moderate (-10 to 4), or high (
-11) risk.19
Stress and rest SPECT images were acquired by use of a
large-field-of-view rotating gamma camera equipped with a
high-resolution, parallel-hole collimator.2 16 Images were
computer quantified and displayed as polar maps by an experienced
investigator (J.J.M.) who had no knowledge of the EBCT or ETT
results.2 5 Raw data polar maps for each subject were
statistically compared with those in a corresponding stressor and
radiopharmaceutical specific normal data bank to determine total left
ventricular perfusion defect size and the extent of scar
and ischemia. Perfusion defects were localized to specific
vascular territories, and a 3% focal defect was considered
abnormal.2 A 15% stress-induced perfusion defect
defined high risk for cardiac events.3 4
Statistical Analysis
Unpaired t tests were used to compare (1) clinical
and EBCT variables in subjects who did or did not have SPECT (Table 1
) and (2) EBCT, SPECT, and ETT variables in those who had
all tests. Discrete data variables were examined by use of
2 analysis. Stepwise logistic
regression (Minitab for Windows 95) identified variables
independently associated with abnormalities on SPECT. Demographic, EBCT
(Table 1), and ETT variables were considered potential
factors for an abnormal SPECT. Variables entered and remained in
the model if the value for an association was P<0.05. A
value of P<0.05 was considered significant. All data are
presented as mean±SD.
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Results |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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EBCT Results
The 411 subjects studied with EBCT and SPECT had a mean CACS of 440±640 (range, 0 to 4611). Calcium was present in the left main artery in 98 subjects (24%) and in the left anterior descending, right, and circumflex arteries in 358 (87%), 294 (72%), and 244 (59%), respectively. Fifteen percent of subjects had calcium in 1 artery, 18% in 2, 40% in 3, and 18% in all 4 major coronary arteries.
By the Agatston scoring system, 37 subjects (9%) were normal and 60
(14.6%) had mild, 155 (37.7%) had moderate, and 159 (38.7%) had
severe CACS. On the basis of absolute CACS, 37 subjects (9%) had no
calcium and 19 (4.6%) had minimal (1 to 10), 76 (18.5%) had mild (11
to 100), 142 (34.5%) had moderate (101 to 399), and 137 (33.4%) had
severe (400) calcium. CACS results for the 411 subjects who had SPECT
and the 3484 who did not are shown in Table 1; 25% and 35% of
all subjects with moderate (101 to 399) or severe (400) CACS had
SPECT compared with 4.5% of subjects with CACS 100.
ETT Results
The mean exercise duration for all subjects was 10±5 minutes, and
17.5% had ECG ischemia. The Duke score was low in 273 subjects
(80%), moderate in 65 (19%), and high in only 4 (1%).
SPECT Results
Of 411 subjects, 81 had an abnormal SPECT with perfusion defects
in the left anterior descending (n=24), right (n=28), and circumflex
(n=45) coronary artery vascular territories. The overall mean
defect size was 3.8±8.0% (range, 0% to 48%) and 13.5±10.6% in
those who had an abnormal SPECT. Large (15%) defects were observed
in 23 of 411 subjects (5.6%).
Comparison of EBCT and SPECT
The mean CACS was significantly higher in subjects who had an
abnormal (1065±983) compared with a normal (286±394,
P<0.00001) SPECT. CACS was also significantly higher in
coronary arteries that supplied abnormally (339±491) compared
with normally (124±237, P<0.0001) perfused
myocardium. On the basis of Agatston score, only 1 of 97
subjects (1%) with a normal or mildly abnormal EBCT had an abnormal
SPECT compared with 16 (10%) and 64 (40%) of those with a moderate or
severe score, respectively (P<0.001).
Absolute CACS results are shown in Figure 1. No one with CACS 10 had an abnormal
SPECT compared with 81 of 355 (23%) with higher scores. Only 2 of 76
subjects (2.6%) with mild CACS and 16 of 142 (11.3%) with a moderate
score had an abnormal SPECT. All had ischemia localized to 1
vascular bed, and only 2 had a large (15%) stress-induced perfusion
defect. Conversely, 63 of 137 subjects (46%) with severe CACS had an
abnormal SPECT, which involved multiple vascular beds in 15 subjects
(24%). Large (15%) perfusion defects were observed in a
significantly greater number of subjects with severe (21 of 137,
15.3%) compared with moderate (1 of 142, 0.7%) CACS
(P<0.0001).
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In the subgroup of 357 entirely asymptomatic subjects,
abnormal SPECT results were similar to those found in the total cohort:
1 of 111 (0.9%) with a score 100, 12 of 122 (9.8%) with a score of
101 to 399, and 59 of 124 (47.6%) with a score 400. Likewise, only 1
of 122 (0.8%) asymptomatic subjects with moderate CACS had
a large (15%) perfusion defect compared with 19 of 124 (15.3%) of
those with a severe score (P<0.001).
CACS predicted an abnormal SPECT regardless of subject age or sex
although women with severe CACS were less likely to have an abnormal
SPECT compared with men (16% versus 51%, P=0.004; Table 3). An abnormal SPECT was again observed
predominantly in subjects with CACS 400. In the total population of
3895 subjects, only a minority (10%) had a score 400 (Table 1).
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Exercise SPECT Versus EBCT
Most subjects who performed ETT had a normal SPECT and stress ECG
(71%) and a low-risk Duke treadmill score (68%). However, 15% of 338
subjects with a low- or moderate-risk Duke score had an abnormal SPECT,
and 16 (4.7%) had large (15%) perfusion defects. Few of the 342
subjects had an abnormal SPECT and concomitant ECG ischemia
(4.4%) or a high-risk Duke score (1%).
Although a similar percentage of subjects had an abnormal SPECT
(16.1%) or stress ECG (17.5%, P=NS), only the former was
related to total CACS (Figure 2). No one
with a score 100 had an abnormal SPECT compared with 40% of those
with scores 400; an abnormal exercise ECG was observed across a wide
spectrum of CACS severity (Figure 2). The mean CACS was
significantly lower in subjects with a normal compared with an abnormal
SPECT regardless of the exercise ECG findings (Figure 3). The Duke treadmill score
significantly decreased as CACS increased from 100 (9.05±4.5) to 101
to 399 (7.89±4.5) to 400 (6.48±6.25, P<0.007; Figure 4). Yet the vast majority of subjects had
either a low- or moderate-risk Duke score that was evenly distributed
across all CACS severities (Figure 4). A
representative subject with severe CACS who had
discordant SPECT and exercise ECG results is shown in Figure 5.
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indicates normal; 
, abnormal.
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Predictors of an Abnormal SPECT
Total CACS was an important univariate predictor of an
abnormal SPECT (Table 4). By logistic
regression, CACS was the best single predictor of an abnormal SPECT
(P<0.0001), followed by male sex (P<0.01) and
diabetes mellitus (P<0.01). In those who performed ETT,
total CACS was again the best predictor (P<0.0001),
followed by male sex (P<0.05) and maximal exercise heart
rate (P<0.05). Univariate and
multivariate test results were similar in the 357
asymptomatic patients and in the entire 411 subject
cohort.
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Discussion |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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This study is the first to describe the relationship between severity of coronary artery calcification detected by EBCT and the presence of stress-induced myocardial ischemia in a large cohort of predominantly asymptomatic subjects with risk factors for CAD development. The presence and extent of stress-induced myocardial ischemia detected by SPECT are known to predict subsequent outcome.3 4 5 6 7 8 Our results indicate that most subjects with coronary calcium do not have inducible ischemia but that the likelihood of ischemia increases with total CACS, particularly with scores
400. In fact, total CACS
400 identified a group in whom a large percentage of subjects (46%)
had demonstrable ischemia. Conversely, only 6.6% of those with
scores <400 had an ischemic defect size by SPECT, and
virtually all (99.3%) were small. These observations suggest that CACS
400 could be used to improve the selection and use of more definitive
and expensive tests such as SPECT for identifying individuals at high
risk for cardiac events within the next year. In our study, the best predictor of an abnormal SPECT was CACS. This result is consistent with previous studies demonstrating that the angiographic extent and severity of CAD are directly related to CACS severity11 12 and that angiographic stenosis severity best predicts an abnormal SPECT.2 16 Our findings emphasize that EBCT is more sensitive than either ETT or SPECT for detecting subclinical CAD in which aggressive risk factor modification is warranted and can further identify a subset of individuals at high risk for silent myocardial ischemia in whom additional diagnostic testing and treatment are advisable.
Identifying High-Risk Individuals With Ischemia
The presence and extent of scintigraphic ischemia
predict short-term risk for cardiac events.3 4 5 6 Patients
who have a normal or minimally abnormal SPECT have a <1%/y risk of
death or myocardial infarction compared with a 5- to 10-fold-higher
event rate with larger defects (15%).3 4 5 6 In our study,
total CACS 400 defined a population at high risk for having
scintigraphic ischemia. In fact, 15% of subjects with CACS
400 had large (15%) perfusion defects compared with <1% of those
with lower scores. Thus, most cardiac events should occur in the small
subset of subjects with high CACS. Indeed, a recent large clinical
trial reported that asymptomatic subjects with CACS <400
had an exceedingly low (<0.5%) 1- to 2-year cardiac event rate, with
virtually all events occurring in individuals with higher
scores.20
EBCT for Detection of Subclinical CAD
We specifically chose to compare SPECT and EBCT because of
the well-recognized accuracy of SPECT in detecting
CAD.2 16 17 18 However, most of our subjects (78%) with
coronary calcium had a normal SPECT and would have been
incorrectly labeled as not having coronary
atherosclerosis. Likewise, only 4 (1.3%) with an
abnormal EBCT had a high-risk Duke score. Our results support previous
studies demonstrating that asymptomatic subjects with
cardiac risk factors generally have normal ETT and perfusion
scans.7 8 9 In the Lipid Research Clinics
trial,9 only 8.3% of 3775 asymptomatic men
with hyperlipidemia had exercise-induced ECG
ischemia. In a study of middle-aged siblings of patients with
premature CAD, the stress ECG was abnormal in only 10% and thallium
imaging in 22%.7 In the Baltimore Longitudinal Study on
Aging, few asymptomatic subjects had an abnormal stress ECG
(16%) or thallium perfusion scan (14%).8 Although
subjects who had abnormal results for both tests had a reduced
event-free survival (52%), this was observed in only 5% of
individuals screened; likewise, only 4.4% of our subjects had both
abnormal ETT and perfusion imaging.
The low incidence of abnormal ETT or SPECT precludes their use as primary screening tests for early detection and treatment of CAD. The low incidence of ECG ischemia, particularly of a high-risk Duke score, in our study across a broad spectrum of CACS further emphasizes the poor diagnostic accuracy of ETT in identifying significant CAD in asymptomatic subjects.7 8 9 In fact, ETT and SPECT have both received a class III indication (ie, no justification for their use) for screening asymptomatic individuals.21 22 These tests, however, remain the cornerstone for evaluating risk in symptomatic patients with known or suspected CAD.1 2 3 4 5 6 19
Detection of subclinical CAD seems desirable, particularly in view of recent primary prevention trials demonstrating that aggressive risk factor modification, including treatment of hyperlipidemia, reduces the incidence of subsequent cardiac events.9 23 24 Moreover, many asymptomatic individuals with subclinical CAD die suddenly25 and would not have been identified with ETT or SPECT. In this regard, EBCT is appealing as a relatively low-cost, primary screening technique through which coronary atherosclerosis can be detected and potentially treated before the development of critical coronary artery stenosis and/or stress-induced myocardial ischemia.
Study Limitations
Subjects with CACS >100 were well represented in our
study (29%), but <5% of those with lower scores had SPECT. It is
unlikely, however, that studying a larger population with CACS 100
would have altered our results because these individuals generally have
insignificant CAD by angiography.11 12 14 Another issue is
whether our results vary with subject age. We observed similar
correlations between SPECT and EBCT when individuals were dichotomized
at 50 years of age; analysis by decade of life would require a
larger sample size. Because of the small number of women who had SPECT,
further study in this group is warranted.
Clinical Implications
In asymptomatic populations who have clinical
characteristics similar to those of our cohort, 61 of every 100
individuals screened will have an abnormal EBCT, but only 10 will have
CACS 400, warranting further evaluation with SPECT. Coronary
angiography can then be appropriately reserved for the very few
patients (1% to 2%) who have significant myocardial ischemia.
Our study emphasizes the effectiveness of selectively combining SPECT
with EBCT to identify individuals with silent myocardial
ischemia who may require more intensive therapy with either
anti-ischemic medications and/or coronary
revascularization.
Conclusions
CACS severity measured by EBCT can identify a high-risk group with
silent myocardial ischemia among an otherwise low-risk
heterogeneous population with cardiac risk factors. Our
results support the role of EBCT as a primary screening tool for
identifying individuals with various degrees of subclinical CAD,
particularly those at high risk for short-term events in whom
aggressive diagnosis and therapy are advisable.
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Acknowledgments |
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We gratefully acknowledge the assistance of Maria E. Frias.
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Footnotes |
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Reprint requests to John J. Mahmarian, MD, 6550 Fannin St, SM-1246, Houston, TX 77030-2717.
Guest editor for this article was Bruce Brundage, MD, Bend Memorial Clinic, Bend, Ore.
Received May 25, 1999; revision received August 9, 1999; accepted August 26, 1999.
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M. Terashima, P. K. Nguyen, G. D. Rubin, C. Iribarren, B. K. Courtney, A. S. Go, S. P. Fortmann, and M. V. McConnell Impaired coronary vasodilation by magnetic resonance angiography is associated with advanced coronary artery calcification. J. Am. Coll. Cardiol. Img., March 1, 2008; 1(2): 167 - 173. [Abstract] [Full Text] [PDF]
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 J. W. Askew, T. D. Miller, P. A. Araoz, J. F. Breen, D. O. Hodge, and R. J. Gibbons Abnormal Electron Beam Computed Tomography Results: The Value of Repeating Myocardial Perfusion Single-Photon Emission Computed Tomography in the Ongoing Assessment of Coronary Artery Disease Mayo Clin. Proc., January 1, 2008; 83(1): 17 - 22. [Abstract] [Full Text] [PDF]
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 J. J. Bax, L. H. Young, R. L. Frye, R. O. Bonow, H. O. Steinberg, and E. J. Barrett Screening for Coronary Artery Disease in Patients With Diabetes Diabetes Care, October 1, 2007; 30(10): 2729 - 2736. [Abstract] [Full Text] [PDF]
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 T. Schepis, O. Gaemperli, P. Koepfli, M. Namdar, I. Valenta, H. Scheffel, S. Leschka, L. Husmann, F. R. Eberli, T. F. Luscher, et al. Added Value of Coronary Artery Calcium Score as an Adjunct to Gated SPECT for the Evaluation of Coronary Artery Disease in an Intermediate-Risk Population J. Nucl. Med., September 1, 2007; 48(9): 1424 - 1430. [Abstract] [Full Text] [PDF]
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 C.-D. Lee, D. R Jacobs Jr, P. J Schreiner, C. Iribarren, and A. Hankinson Abdominal obesity and coronary artery calcification in young adults: the Coronary Artery Risk Development in Young Adults (CARDIA) Study Am. J. Clinical Nutrition, July 1, 2007; 86(1): 48 - 54. [Abstract] [Full Text] [PDF]
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G. A. Beller Noninvasive Screening for Coronary Atherosclerosis and Silent Ischemia in Asymptomatic Type 2 Diabetic Patients: Is it Appropriate and Cost-Effective? J. Am. Coll. Cardiol., May 15, 2007; 49(19): 1918 - 1923. [Abstract] [Full Text] [PDF]
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A. Rozanski, H. Gransar, N. D. Wong, L. J. Shaw, R. Miranda-Peats, D. Polk, S. W. Hayes, J. D. Friedman, and D. S. Berman Clinical Outcomes After Both Coronary Calcium Scanning and Exercise Myocardial Perfusion Scintigraphy J. Am. Coll. Cardiol., March 27, 2007; 49(12): 1352 - 1361. [Abstract] [Full Text] [PDF]
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G. Ramakrishna, J. F. Breen, S. L. Mulvagh, R. B. McCully, and P. A. Pellikka Relationship Between Coronary Artery Calcification Detected by Electron-Beam Computed Tomography and Abnormal Stress Echocardiography: Association and Prognostic Implications J. Am. Coll. Cardiol., November 21, 2006; 48(10): 2125 - 2131. [Abstract] [Full Text] [PDF]
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 R. C. Johnson, J. A. Leopold, and J. Loscalzo Vascular Calcification: Pathobiological Mechanisms and Clinical Implications Circ. Res., November 10, 2006; 99(10): 1044 - 1059. [Abstract] [Full Text] [PDF]
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R. A. Vogel Coronary Artery Calcification and Myocardial Perfusion: Kissing Cousins or Distant Relatives? J. Am. Coll. Cardiol., September 5, 2006; 48(5): 1027 - 1028. [Full Text] [PDF]
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L. Wang, M. Jerosch-Herold, D. R. Jacobs Jr, E. Shahar, R. Detrano, A. R. Folsom, and for the MESA Study Investigators Coronary Artery Calcification and Myocardial Perfusion in Asymptomatic Adults: The MESA (Multi-Ethnic Study of Atherosclerosis) J. Am. Coll. Cardiol., September 5, 2006; 48(5): 1018 - 1026. [Abstract] [Full Text] [PDF]
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Developed in Collaboration With the European Heart, D. P. Zipes, A. J. Camm, M. Borggrefe, A. E. Buxton, B. Chaitman, M. Fromer, G. Gregoratos, G. Klein, A. J. Moss, et al. ACC/AHA/ESC 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death: A Report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death) J. Am. Coll. Cardiol., September 5, 2006; 48(5): e247 - e346. [Full Text] [PDF]
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 Writing Committee Members, D. P. Zipes, A. J. Camm, M. Borggrefe, A. E. Buxton, B. Chaitman, M. Fromer, G. Gregoratos, G. Klein, A. J. Moss, et al. ACC/AHA/ESC 2006 guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: A report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death) Developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society Europace, September 1, 2006; 8(9): 746 - 837. [Full Text] [PDF]
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T. Yoshimura, E. Suzuki, K. Egawa, Y. Nishio, H. Maegawa, S. Morikawa, T. Inubushi, A. Hisatomi, K. Fujimoto, and A. Kashiwagi Low Blood Flow Estimates in Lower-Leg Arteries Predict Cardiovascular Events in Japanese Patients With Type 2 Diabetes With Normal Ankle-Brachial Indexes Diabetes Care, August 1, 2006; 29(8): 1884 - 1890. [Abstract] [Full Text] [PDF]
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D. S. Berman, R. Hachamovitch, L. J. Shaw, J. D. Friedman, S. W. Hayes, L. E.J. Thomson, D. S. Fieno, G. Germano, N. D. Wong, X. Kang, et al. Roles of Nuclear Cardiology, Cardiac Computed Tomography, and Cardiac Magnetic Resonance: Noninvasive Risk Stratification and a Conceptual Framework for the Selection of Noninvasive Imaging Tests in Patients with Known or Suspected Coronary Artery Disease J. Nucl. Med., July 1, 2006; 47(7): 1107 - 1118. [Abstract] [Full Text] [PDF]
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 D. V. Anand, E. Lim, D. Hopkins, R. Corder, L. J. Shaw, P. Sharp, D. Lipkin, and A. Lahiri Risk stratification in uncomplicated type 2 diabetes: prospective evaluation of the combined use of coronary artery calcium imaging and selective myocardial perfusion scintigraphy Eur. Heart J., March 2, 2006; 27(6): 713 - 721. [Abstract] [Full Text] [PDF]
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 T. Edvardsen, R. Detrano, B. D. Rosen, J. J. Carr, K. Liu, S. Lai, S. Shea, L. Pan, D. A. Bluemke, and J. A.C. Lima Coronary Artery Atherosclerosis Is Related to Reduced Regional Left Ventricular Function in Individuals Without History of Clinical Cardiovascular Disease: The Multiethnic Study of Atherosclerosis Arterioscler Thromb Vasc Biol, January 1, 2006; 26(1): 206 - 211. [Abstract] [Full Text] [PDF]
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P. Raggi, A. Bellasi, and C. Ratti Ischemia Imaging and Plaque Imaging in Diabetes: Complementary tools to improve cardiovascular risk management Diabetes Care, November 1, 2005; 28(11): 2787 - 2794. [Abstract] [Full Text] [PDF]
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 E. Rzewuska-Lech, M. Jayachandran, L. A. Fitzpatrick, and V. M. Miller Differential effects of 17{beta}-estradiol and raloxifene on VSMC phenotype and expression of osteoblast-associated proteins Am J Physiol Endocrinol Metab, July 1, 2005; 289(1): E105 - E112. [Abstract] [Full Text] [PDF]
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N. D. Wong, A. Rozanski, H. Gransar, R. Miranda-Peats, X. Kang, S. Hayes, L. Shaw, J. Friedman, D. Polk, and D. S. Berman Metabolic Syndrome and Diabetes Are Associated With an Increased Likelihood of Inducible Myocardial Ischemia Among Patients With Subclinical Atherosclerosis Diabetes Care, June 1, 2005; 28(6): 1445 - 1450. [Abstract] [Full Text] [PDF]
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 S. Lai, J. A. C. Lima, H. Lai, D. Vlahov, D. Celentano, W. Tong, J. G. Bartlett, J. Margolick, and E. K. Fishman Human Immunodeficiency Virus 1 Infection, Cocaine, and Coronary Calcification Arch Intern Med, March 28, 2005; 165(6): 690 - 695. [Abstract] [Full Text] [PDF]
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M. F. Di Carli and R. Hachamovitch Should we screen for occult coronary artery disease among asymptomatic patients with diabetes? J. Am. Coll. Cardiol., January 4, 2005; 45(1): 50 - 53. [Abstract] [Full Text] [PDF]
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R. Vliegenthart, H.-H. S. Oei, A. P. M. van den Elzen, F. J. A. van Rooij, A. Hofman, M. Oudkerk, and J. C. M. Witteman Alcohol Consumption and Coronary Calcification in a General Population Arch Intern Med, November 22, 2004; 164(21): 2355 - 2360. [Abstract] [Full Text] [PDF]
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M. Tsuchiya, E. Suzuki, K. Egawa, Y. Nishio, H. Maegawa, S. Inoue, K. Mitsunami, S. Morikawa, T. Inubushi, and A. Kashiwagi Stiffness and Impaired Blood Flow in Lower-Leg Arteries Are Associated With Severity of Coronary Artery Calcification Among Asymptomatic Type 2 Diabetic Patients Diabetes Care, October 1, 2004; 27(10): 2409 - 2415. [Abstract] [Full Text] [PDF]
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D. S. Berman, N. D. Wong, H. Gransar, R. Miranda-Peats, J. Dahlbeck, S. W. Hayes, J. D. Friedman, X. Kang, D. Polk, R. Hachamovitch, et al. Relationship between stress-induced myocardial ischemia and atherosclerosis measured by coronary calcium tomography J. Am. Coll. Cardiol., August 18, 2004; 44(4): 923 - 930. [Abstract] [Full Text] [PDF]
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P. F. Cohn, K. M. Fox, and C. Daly Silent Myocardial Ischemia Circulation, September 9, 2003; 108(10): 1263 - 1277. [Full Text] [PDF]
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 G. M. London Cardiovascular Calcifications in Uremic Patients: Clinical Impact on Cardiovascular Function J. Am. Soc. Nephrol., September 1, 2003; 14(90004): S305 - 309. [Abstract] [Full Text]
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 K. Watanabe, T. Hiroki, and N. Koga Relation of Thoracic Aorta Calcification on Computed Tomography and Coronary Risk Factors to Obstructive Coronary Artery Disease on Angiography Angiology, July 1, 2003; 54(4): 433 - 441. [Abstract] [PDF]
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 K Pohle, D Ropers, R Maffert, P Geitner, W Moshage, M Regenfus, M Kusus, W G Daniel, and S Achenbach Coronary calcifications in young patients with first, unheralded myocardial infarction: a risk factor matched analysis by electron beam tomography Heart, June 1, 2003; 89(6): 625 - 628. [Abstract] [Full Text] [PDF]
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J. Shemesh, S. Apter, Y. Itzchak, and M. Motro Coronary Calcification Compared in Patients with Acute versus in Those with Chronic Coronary Events by Using Dual-Sector Spiral CT Radiology, February 1, 2003; 226(2): 483 - 488. [Abstract] [Full Text] [PDF]
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C. Daly, P. Saravanan, and K. Fox Is calcium the clue? Eur. Heart J., October 2, 2002; 23(20): 1562 - 1566. [Full Text] [PDF]
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A. B. Newman, B. L. Naydeck, K. Sutton-Tyrrell, D. Edmundowicz, D. O'Leary, R. Kronmal, G. L. Burke, and L. H. Kuller Relationship Between Coronary Artery Calcification and Other Measures of Subclinical Cardiovascular Disease in Older Adults Arterioscler Thromb Vasc Biol, October 1, 2002; 22(10): 1674 - 1679. [Abstract] [Full Text] [PDF]
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 R. C. Christian, S. Harrington, W. D. Edwards, A. L. Oberg, and L. A. Fitzpatrick Estrogen Status Correlates with the Calcium Content of Coronary Atherosclerotic Plaques in Women J. Clin. Endocrinol. Metab., March 1, 2002; 87(3): 1062 - 1067. [Abstract] [Full Text] [PDF]
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R. Wayhs, A. Zelinger, and P. Raggi High coronary artery calcium scores pose an extremely elevated risk for hard events J. Am. Coll. Cardiol., January 16, 2002; 39(2): 225 - 230. [Abstract] [Full Text] [PDF]
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J. A. Beckman, J. Ganz, M. A. Creager, P. Ganz, and S. Kinlay Relationship of Clinical Presentation and Calcification of Culprit Coronary Artery Stenoses Arterioscler Thromb Vasc Biol, October 1, 2001; 21(10): 1618 - 1622. [Abstract] [Full Text] [PDF]
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H. S. Hecht and H. R. Superko Electron beam tomography and national cholesterol education program guidelines in asymptomatic women J. Am. Coll. Cardiol., May 1, 2001; 37(6): 1506 - 1511. [Abstract] [Full Text] [PDF]
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S. Schurgin, S. Rich, and T. Mazzone Increased Prevalence of Significant Coronary Artery Calcification in Patients With Diabetes Diabetes Care, February 1, 2001; 24(2): 335 - 338. [Abstract] [Full Text]
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S. G. ROSTAND Coronary Heart Disease in Chronic Renal Insufficiency: Some Management Considerations J. Am. Soc. Nephrol., October 1, 2000; 11(10): 1948 - 1956. [Full Text]
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 EBCT Predicts Silent Ischemia Journal Watch Cardiology, March 3, 2000; 2000(303): 5 - 5. [Full Text]
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