Low Coronary Artery Calcium Score Research Articles

Abstract 18337: Comparison of the Distribution and Predictive Value of Framingham Risk Factors and Coronary Artery Calcium for Major Coronary Events Between Asian (South Korean) and Framingham Cohorts

Background: Coronary artery calcium (CAC) predicts major adverse cardiovascular events (MACE) beyond Framingham risk factors (RF) across multiple ethnic groups within the United States. However, its value in other, non-US populations is unknown. Methods: We prospectively obtained data on RF and MACE in asymptomatic adults from the registry-based ESCORT Study (4502 Koreans) and the population-based Framingham Heart Study (FHS, 3141 Whites), who underwent computed tomography to assess CAC. The primary composite endpoint of MACE included CV death, acute myocardial infarction and unstable angina with revascularization. We compared association of traditional RF and CAC with MACE in the two cohorts using multivariate Cox proportional hazard regression analysis, examining CAC both as a categorical variable using established cut-points and as a continuous variable using log 2 [CAC + 1]. We tested for interaction between ethnicity and CAC categories. Results: Over median 55 (ESCORT) or 60 (FHS) month follow-up, there were 95 MACE (ESCORT=45, FHS=50). ESCORT participants had greater prevalence of smoking, diabetes and hypertension (p<0.001 all) and greater 10-year Framingham risk score (11.4% vs 8.2%). In contrast, mean CAC prevalence and score were significantly lower in ESCORT (21.9%, 25.3 Agatston units, AU) vs FHS (41.5%, 99.9 AU). In ESCORT, more RF (age, male sex, systolic BP, HDL_C, diabetes) were predictive of MACE vs FHS (age only.) After adjustment for standard RF, doubling of CAC score (1-unit increase in log 2 [CAC + 1]) resulted in a 40% increase in risk of MACE in each cohort. Low CAC (1-100) was a significant predictor of MACE only in ESCORT but not in FHS (interaction p-value = 0.099.) Conclusion: There were significant differences in the burden and distribution of RF and CAC between Asian (South Korean) and white US (FHS) cohorts . CAC is a strong predictor of MACE in both cohorts, however lower CAC scores have greater predictive value in the Korean cohort.

FGF-23 associated with the progression of coronary artery calcification in hemodialysis patients

BackgroundDisordered mineral metabolism is implicated in the pathogenesis of vascular calcification in hemodialysis (HD) patients. Fibroblast growth factor 23 (FGF-23) is the main regulator of phosphate metabolism. In this prospective study, we aimed to investigate the association of serum FGF-23 with progression of coronary artery calcification in HD patients.MethodsSeventy-four HD patients (36 male/38 female, mean age: 52 ± 14 years) were included. Serum FGF-23 levels were measured by ELISA. Coronary artery calcification score (CACS) was measured twice with one year interval. Patients were grouped as progressive (PG) (36 patients-48%) and non-progressive (NPG).ResultsAge, serum phosphorus, baseline and first year CACS were found to be significantly higher in the PG compared to NPG group. Serum FGF-23 levels were significantly higher in PG [155 (80–468) vs 147 (82–234), p = 0.04]. Patients were divided into two groups according to baseline CACS (low group, CACS ≤ 30; high group, CACS > 30). Serum FGF-23 levels were significantly correlated with the progression of CACS (ΔCACS) in the low baseline CACS group (r = 0.51, p = 0.006), but this association was not found in high baseline CACS group (r = 0.11, p = 0.44). In logistic regression analysis for predicting the PG patients; serum FGF-23, phosphorus levels and baseline CACS were retained as significant factors in the model.ConclusionsSerum FGF-23 was found to be related to progression of CACS independent of serum phosphorus levels. FGF-23 may play a major role in the progression of vascular calcification especially at the early stages of calcification process in HD patients.

Plasma levels of advanced glycation endproducts are associated with type 1 diabetes and coronary artery calcification

BackgroundAdvanced glycation endproducts (AGEs) may play a role in the development of coronary artery calcification (CAC) in type 1 diabetes (T1DM). We studied plasma AGEs in association with T1DM and CAC, and whether or not the latter association could be explained by low-grade inflammation (LGI) or endothelial dysfunction (ED).MethodsWe studied 165 individuals with and 169 without T1DM. CAC was quantified in a CAC score based on CT-scanning. Plasma levels of protein-bound pentosidine, Nϵ-(carboxymethyl)lysine (CML) and Nϵ-(carboxyethyl)lysine (CEL) were measured with HPLC/UPLC with fluorescence detection or tandem-mass spectrometry. Tetrahydropyrimidine (THP) was measured with ELISA, as were HsCRP, and sVCAM-1 and vWF, as markers for LGI and ED, respectively. Associations were analyzed with ANCOVA and adjusted for age, sex, BMI, waist-to-hip ratio, smoking, blood pressure, lipid profile, eGFR and T1DM.ResultsIndividuals with T1DM had higher plasma levels of pentosidine, CML and THP compared with controls; means (95% CI) were 0.69 (0.65-0.73) vs. 0.51 (0.48-0.54) nmol/mmol LYS, p < 0.001; 105 (102–107) vs. 93 (90–95) nmol/mmol LYS, p < 0.001; and 126 (118–134) vs. 113 (106–120) U/mL, p = 0.03, respectively. Levels of pentosidine were higher in individuals with T1DM with a moderate to high compared with a low CAC score, means (95% CI) were 0.81 (0.70-0.93) vs. 0.67 (0.63-0.71) nmol/mmol LYS, p = 0.03, respectively. This difference was not attenuated by adjustment for LGI or ED.ConclusionsWe found a positive association between pentosidine and CAC in T1DM. These results may indicate that AGEs are possibly involved in the development of CAC in individuals with T1DM.

The coronary calcium treadmill test: A new approach to the initial workup of patients with suspected coronary artery disease

Due to the growth of cardiac testing and increasing cost of cardiovascular healthcare, the development of more cost-effective strategies has now become a dominant issue regarding future utilization of cardiac imaging procedures. To that end, we review the potential of combining two relatively inexpensive tests, the coronary artery calcium (CAC) scan and exercise electrocardiography (ECG), as a first-line test for the workup of patients with suspected coronary artery disease (CAD). The CAC scan was initially introduced as a screening test for CAD, based on data indicating that it is a specific marker for atherosclerosis, predicts clinical risk in accordance with the magnitude of CAC, and provides incremental information for prognostic risk compared to more readily available clinical data. However, CAC scores also predict the likelihood of observing myocardial ischemia among patients undergoing exercise myocardial perfusion SPECT imaging. Exercise ECG predicts clinical events according to the ST-segment response and according to functional exercise capacity, with the latter parameter as a stronger predictor of clinical outcomes. Like CAC scores, exercise functional capacity can also be used to predict the likelihood of ischemia since ischemia diminishes proportionally with increasing exercise capacity. Recent work indicates that when patients are designated by Bayesian analyses into low, intermediate, and high likelihood categories for CAD based on clinical data and the response to exercise ECG, the frequency of inducible myocardial ischemia is very low among both low and intermediate CAD likelihood patients who have a CAC score <400. Future studies are needed to investigate what clinical factors might further modify the CAC-ischemia relationship. On the basis of current data, an initial testing strategy that employs the combined calcium treadmill test has the inherent ability to designate a substantial number of intermediate likelihood patients who would not require further testing due to relatively low CAC scores and reasonable functional capacity.

Relation of Estimated Glomerular Filtration Rate to the Presence of Coronary Plaque and Obstructive Coronary Artery Disease in a Zero or Low Coronary Artery Calcium Score

Objectives: Although renal dysfunction is associated with the presence of atherosclerosis, little is known about the relationship between reduced estimated glomerular filtration rate (eGFR) and the presence of atherosclerosis detected by coronary computed tomographic angiography (CCTA). This study evaluated the relation of eGFR to the presence of coronary plaque and obstructive coronary artery disease (CAD) in patients with a zero or low coronary artery calcium score (CACS). Methods: Coronary artery calcium scoring and CCTA were performed with CT scanners. Serum creatinine was measured before CCTA, and GFR was estimated. A total of 720 patients with a CACS ≤10 were enrolled. Results: Coronary plaque was detected in 118 patients. Of the 118 patients, 36 had a diagnosis of obstructive CAD. The multiple-adjusted odds ratios of presenting with coronary plaque and obstructive CAD were 1.82 (95% CI 1.06-3.12, p = 0.030) and 1.79 (95% CI 0.71-4.49, p = 0.217) for the lowest tertile of eGFR compared with the highest tertile, respectively. Conclusions: Lower eGFR levels were associated with the presence of coronary plaque in patients with a zero or low CACS. However, the association between eGFR and the presence of obstructive CAD was not statistically significant.

GW24-e1020 Association of mild to moderate kidney dysfunction with coronary artery calcification in patients with suspected coronary artery disease

ObjectivesTo report the association between kidney dysfunction and coronary artery calcification (CAC) score (CACS) among patients with clinically suspected coronary artery disease (CAD).MethodsWe prospectively included 1,572 consecutive patients with clinically...

Sevelamer Versus Calcium Carbonate in Incident Hemodialysis Patients: Results of an Open-Label 24-Month Randomized Clinical Trial

Whether the use of sevelamer rather than a calcium-containing phosphate binder improves cardiovascular (CV) survival in patients receiving dialysis remains to be elucidated. Open-label randomized controlled trial with parallel groups. 466 incident hemodialysis patients recruited from 18 centers in Italy. Study participants were randomly assigned in a 1:1 fashion to receive either sevelamer or a calcium-containing phosphate binder (although not required by the protocol, all patients in this group received calcium carbonate) for 24 months. All individuals were followed up until completion of 36 months of follow-up or censoring. CV death due to cardiac arrhythmias was regarded as the primary end point. Blind event adjudication. At baseline, patients allocated to sevelamer had higher serum phosphorus (mean, 5.6 ± 1.7 [SD] vs 4.8 ± 1.4 mg/dL) and C-reactive protein levels (mean, 8.8 ± 13.4 vs 5.9 ± 6.8 mg/dL) and lower coronary artery calcification scores (median, 19 [IQR, 0-30] vs 30 [IQR, 7-180]). At study completion, serum phosphate levels were lower in the sevelamer arm (median dosages, 4,800 and 2,000 mg/d for sevelamer and calcium carbonate, respectively). After a mean follow-up of 28 ± 10 months, 128 deaths were recorded (29 and 88 due to cardiac arrhythmias and all-cause CV death). Sevelamer-treated patients experienced lower CV mortality due to cardiac arrhythmias compared with patients treated with calcium carbonate (HR, 0.06; 95% CI, 0.01-0.25; P < 0.001). Similar results were noted for all-cause CV mortality and all-cause mortality, but not for non-CV mortality. Adjustments for potential confounders did not affect results. Open-label design, higher baseline coronary artery calcification burden in calcium carbonate-treated patients, different mineral metabolism control in sevelamer-treated patients, overall lower than expected mortality. These results show that sevelamer compared to a calcium-containing phosphate binder improves survival in a cohort of incident hemodialysis patients. However, the better outcomes in the sevelamer group may be due to better phosphate control rather than reduction in calcium load.

SIGNIFICANT CORONARY ARTERY STENOSIS IN PATIENTS WITH LOW CORONARY ARTERY CALCIUM SCORE

Background: Coronary artery disease is a major cause of morbidity and mortality. Non-invasive techniques for diagnosis are becoming increasingly popular and multidetector coronary computed tomography has emerged as a promising modality. Quantifying the amount of coronary artery calcium with unenhanced CT calcium score has been shown to be a reliable noninvasive technique for screening risk of future cardiac events. In previous trials low coronary artery calcium score has been shown to rule out coronary artery disease with high predictive value.&#x0D; Objective: To evaluate the level of agreement between severity of stenosis on CT angiography and calcium burden as measured by dedicated CT protocols for calcium scoring, comparing their results.&#x0D; Material and Method: The study was conducted at Radiology Department, Shaukat Khanum Memorial Cancer Hospital and Research Centre and Heart and Body Scan Centre, Lahore. Duration of study was 6 months. The study design was a cross sectional survey.&#x0D; Results: Mean age of patients was 38.65+5.72. Male to female ratio was 2.5:1 (72 males: 27 females).Agreement of low calcium score and insignificant coronary stenosis was found in 78 patients while 22 showed no agreement. Kappa test was applied, p value was recorded. 0.0005. 50% (11 out of 22) of the patients with calcium score of 0 had significant coronary stenosis.&#x0D; Conclusion: The results of study reveal that absence of calcium or low calcium does not exclude significant coronary stenosis. Depending on presentation, it is recommended to get calcium score and coronary CT angiography done in the same setting.

Jaki jest optymalny punkt odcięcia niskiego indeksu zwapnień tętnic wieńcowych? Multi-Detector Computed Tomography ANIN Registry

AimThis prospective study was conducted to evaluate the incidence and predictors of coronary artery disease (CAD) in relation to the low coronary artery calcium (CAC) score among patients with intermediate probability of CAD.Material and methodsA total of 1132 consecutive patients were included in the analysis (58.7 ±10.9 years, 46.7% males). Coronary computed tomography (CCT) angiography was performed in a multi-detector computed tomography scanner. Coronary artery calcium score was calculated by the Agatston method. Obstructive CAD was defined as the presence of coronary artery stenosis ≥ 50% on CCT angiography.ResultsCoronary artery disease was diagnosed in nearly one-fourth of patients (n = 272, 24%). In the receiver operating characteristics (ROC) curve analysis a CAC score of 10 was used as an optimal cut-off point for discriminating obstructive CAD (sensitivity: 0.79, specificity: 0.75, p < 0.0001) whereas for a CAC score of 100 the sensitivity and specificity were 0.48 and 0.92, respectively. On multivariate analysis after adjustment for age, gender, hypertension, hyperlipidemia, creatinine levels, only in patients with CAC score ≤ 10 age (OR = 1.05, 95% CI: 1.02-1.08, p = 0.0005, OR = 1.05, 95% CI: 1.03-1.08, p < 0.0001) and male gender (OR = 3.45, 95% CI: 1.92-6.22, p < 0.0001), likewise in group with CAC score ≤ 100 age (OR = 1.05, 95% CI: 1.03-1.08, p < 0.0001) and male gender (OR = 3.31, 95% CI: 1.88-5.81, p < 0.0001) were independent predictors of obstructive CAD.ConclusionsThe cut-off point of 10 for CAC score determined patients with CAD with the best sensitivity and specificity. Therefore, a total CAC score < 10 should be classified as “low”. In patients with a low CAC score obstructive high risk plaques prone to rupture are presented and are associated with increasing age and male gender.

Prevalence of coronary atherosclerotic plaque in patients with a low coronary artery calcium score

Patients with low coronary artery calcium (CAC) scores are deemed to be at low risk of future cardiac events. It is unclear what the prevalence of significant coronary disease is in these patients. It is also not established what cluster of traditional cardiovascular risk factors predict the presence of any coronary plaque in this group. We hypothesised patients with a calcium score of < 10 Agatston Units may have significant coronary plaque lesions that would be picked up on a more robust method for the evaluation of coronary plaques such as CT coronary angiography (CTCA).

Association Between Low Serum Free Thyroxine Concentrations and Coronary Artery Calcification in Healthy Euthyroid Subjects

Considerable evidence suggests that hypothyroidism could promote atherosclerotic vascular changes. We planned this study to investigate whether serum free thyroxine (FT4) or thyroid-stimulating hormone (TSH) levels are associated with coronary artery calcification measured in healthy euthyroid subjects. A cross-sectional analysis was performed among subjects who visited our hospital for a health checkup. Among 1849 subjects, 669 (mean age 55.3±8.8 years; 392 men) with FT4 and TSH in the normal ranges were included after excluding those with diabetes, a history of current smoking and cardiovascular disease (CVD), or the use of drugs for hypertension, antithyroid drugs, or thyroid hormone preparations. Coronary artery calcium scores (CACS) were measured by multi-detector computed tomography. Subjects with a CACS >100 had lower FT4 levels than those with a lower CACS (p=0.017), whereas no difference was observed in the TSH levels among CACS categories. FT4 levels had an odds ratio of 0.06 for high CACS (95% confidence interval=0.01-0.74; p=0.028) after the adjustment for CVD risk factors. In multivariate regression analysis, CACS was negatively correlated with FT4 levels (β=-0.823, p=0.032), and the inverse association between FT4 and CACS remained significant only in men (p=0.011). FT4 levels were inversely associated with coronary artery calcification in euthyroid healthy subjects, especially in men independent of conventional CVD risk factors. Further studies are needed to validate whether subjects with decreased FT4 levels within the normal reference range are at a high CVD risk and have poor cardiovascular outcomes.

Coronary Calcium Score as an Adjunct to Nuclear Myocardial Perfusion Imaging for Risk Stratification Before Noncardiac Surgery

The purpose of this study was to evaluate the added value of coronary artery calcium score (CACS) as an adjunct to myocardial perfusion imaging (MPI) with SPECT for cardiac risk stratification before noncardiac surgery. SPECT MPI is a well-established and widely used tool for preoperative risk stratification before noncardiac surgery. The potential added value of combining SPECT MPI with CACS is unknown. We included 326 consecutive patients who were referred for SPECT MPI for preoperative cardiac risk assessment before elective noncardiac surgery. All patients underwent an additional low-dose CT scan for CACS and SPECT MPI. Patients were followed up for 40 d after their index surgical procedure, and the occurrence of major adverse cardiovascular events (MACE), including death, myocardial infarction, revascularization, stroke, and sudden cardiac death, was registered. Postoperative MACE occurred in 30 patients (9%). Cumulative MACE rate was highest in patients with abnormal SPECT and high CACS (22%), defined by a cutoff value CACS of 1,314 or more, and lowest in patients with normal SPECT MPI findings and low CACS (5%) (CACS < 1,314). A CACS score of 1,314 or more was independently associated with a higher MACE rate in patients with normal (12% vs. 5%) or abnormal perfusion (22% vs. 12%, P < 0.05 for all intergroup comparisons). SPECT MPI findings and CACS are strong preoperative risk predictors. CACS allows further risk stratification, indicating very low risk when CACS less than 1,314 is associated with normal SPECT MPI findings. Conversely, in patients with abnormal SPECT MPI findings, a CACS of 1,314 or more confers an added value for predicting adverse outcomes.

Association of Mild to Moderate Kidney Dysfunction with Coronary Artery Calcification in Patients with Suspected Coronary Artery Disease

Objectives: To report the association between kidney dysfunction and coronary artery calcification (CAC) score (CACS) among patients with clinically suspected coronary artery disease (CAD). Methods: We prospectively included 1,572 consecutive patients with clinically suspected CAD who underwent ECG-gated cardiac CT scans using 64-multidetector row computed tomography. CACS was quantified using a previously described method. Renal function was assessed by the estimated glomerular filtration rate (eGFR). Ordinal logistic regression and Pearson correlation were used to analyze the association between eGFR and CACS. Results: Patients with higher CACS were older, more had a history of hypertension, diabetes and tobacco use, and they were more likely to have an atherogenic lipid profile, higher systolic blood pressure, diastolic blood pressure, hemoglobin A1c, body mass index and C-reactive protein (CRP) and lower eGFR when compared with those patients without CAC or with lower CACS. The unadjusted correlation coefficient of eGFR and CACS was –0.259 (p < 0.001). This remained significant after adjustment for age, gender, hypertension, diabetes, hyperlipidemia, tobacco use and CRP (R = –0.156, p < 0.001). Ordinal logistic regression analysis showed that age, hypertension, diabetes, CRP and eGFR exerted independent influences on CACS. Conclusions: Kidney dysfunction was an independent predictor of CACS in patients with clinically suspected CAD. Further prospective multicenter studies are needed to confirm this finding.

Significance of noncalcified coronary plaque in asymptomatic subjects with low coronary artery calcium score: assessment with coronary computed tomography angiography

We aimed to investigate the prevalence and severity of noncalcified coronary plaques (NCP) using coronary CT angiography (CCTA) and analyze predictors of significant coronary stenosis by NCP in asymptomatic subjects with low coronary artery calcium score (CACS). The institutional review board approved this retrospective study and all patients gave written, informed consent. The presence of plaque, severity of stenosis, plaque characteristics, and CACS were assessed in 7,515 asymptomatic subjects. We evaluated the prevalence and severity of NCP in subjects having low CACS (707 subjects; men with CACS from 1 to 50 and women from 1 to 10) in comparison to those having 0 CACS (6,040 subjects) as the reference standard. Conventional risk factors were assessed for predictors of NCP and significant stenosis by NCP. We also investigated the cardiac events of the patients through medical records. Compared to subjects with 0 CACS, those with low CACS showed higher prevalence of NCP (6.9% vs. 31.5%, P < 0.001) and significant stenosis caused by NCP (0.8% vs. 7.5%, P < 0.001). In the low CACS group, independent predictors for significant NCP included diabetes mellitus (DM), hypertension, and elevated low-density lipoprotein (LDL)-cholesterol (all P < 0.05). However, 47.2% of subjects with significant NCP were classified into the low to intermediate risk according to Framingham Risk Score. At the median follow up of 42 months (range: 3-60 months), cardiac events were significantly higher in the low CACS group compared to the 0 CACS group (2.6% vs. 0.27%, P < 0.001). In asymptomatic subjects having low CACS, the prevalence and severity of NCP were higher as compared to subjects having zero CACS and predictors of significant stenosis by NCP were DM, hypertension and LDL-Cholesterol. Therefore, CCTA may be useful for risk stratification of coronary artery disease as added value over CACS in selected populations with low CACS who have predictors of significant NCP.

Influence of coronary calcification on the diagnostic accuracy of 64-slice computed tomography coronary angiography: a systematic review and meta-analysis

To determine via meta-analysis the diagnostic accuracy of 64-slice computed tomography coronary angiography (CTA) for assessment of significant obstructive coronary artery stenosis at different coronary artery calcium score (CACS) levels. Data of 12,053 versus 5,890 segments, 906 versus 758 arteries and 1,120 versus 514 patients in low versus high CACS subgroups from 19 eligible studies were compared. The per-patient prevalence of coronary artery disease was 48% versus 68%, respectively. Subgroups were stratified by different CACS thresholds ranging from 100 to 400. Meta-analyses of per-patient data comparing overall low versus high CACS subgroups resulted in a sensitivity of 97.5 (95.5-99)% versus 97 (94.5-98.5)%, specificity of 85 (82-88)% versus 66.5 (58-74.5)%, diagnostic odds ratio of 153 (81-290) versus 40 (20-83), positive predictive value of 85 (82-87)% versus 86 (84-88)%, negative predictive value of 97.5 (95-99)% versus 91 (88-94)% and overall accuracy of 91% versus 89% with 95% confidence interval, respectively. The drop in specificity was significant (P=0.035), while the sensitivity and overall accuracy were insignificantly changed (P>0.05). Meta-analyses of independent subgroups at CACS levels ≤10 and ≤100 demonstrated high specificities of 90 (94-100)% and 88.5 (81-91.5)%, whereas at CACS levels ≥400 the specificity declined significantly to 42 (28-56)% but with consistently retained high sensitivity of 97.5 (94-99)%. The specificity of CTA decreases with increasing CACS, while the sensitivity remains high independent of that. The suggested CACS thresholds are arbitrary and do not necessarily warrant cancelling angiography. Diagnostic studies are needed to explore whether a specific CACS threshold may serve as a pre-angiographic gatekeeper to prevent likely equivocal angiographies.

Total Parathyroidectomy with Forearm Autotransplantation as the Treatment of Choice for Secondary Hyperparathyroidism

Chronic kidney disease-mineral and bone disease (CKD-MBD) is associated with uraemic bone disease, vascular calcification, reduced quality of life and reduced survival. This study evaluated the efficacy of parathyroidectomy (PTX) with autotransplantation in improving short-term and long-term outcomes. Dialysis patients who underwent PTX showed significantly more favourable biochemical parameters after PTX. These changes were accompanied by a lower coronary artery calcification score, reduced thickness of the intimae media and comparable bone mineral density measures compared with control dialysis patients who did not undergo PTX. Despite the risk of a substantially lower intact parathyroid hormone level postoperatively that might lead to adynamic bone disease, none of the patients reported clinical signs of this disease, such as bone pain or fractures. In conclusion, PTX with autotransplantation led to improvement of CKD-MBD so may be considered in patients with secondary hyperparathyroidism that is resistant to treatment with vitamin D analogues and calcimimetics.

Relation of cardiovascular risk factors and angina status to obstructive coronary artery disease according to categorical coronary artery calcium score

Coronary artery calcium (CAC) is associated with the presence of coronary artery disease (CAD) and cardiovascular risk factors. However, the relation between cardiovascular risk factors and CAD has not yet been fully elucidated in patients with a zero or low coronary artery calcium score (CACS). The purpose of this study was to evaluate the relation of cardiovascular risk factors and angina status to obstructive CAD according to categorical CACS. A total of 753 patients were enrolled in this study. CAC scoring and coronary computed tomographic angiography (CCTA) were performed with dual-source 64-slice CT scanners. The number of patients with a CACS≤10 and ≤100 were 358 and 528, respectively. Patients with a higher CACS were older and more frequently male, and had a greater frequency of hypertension, diabetes, and hypercholesterolemia. The prevalence of obstructive CAD increased with the CACS. Among patients with a CACS≤100, age, male gender, diabetes, hypercholesterolemia, and typical angina pectoris were related to obstructive CAD. The presence of hypercholesterolemia was relatively strongly associated with obstructive CAD (OR 6.67, 95% CI 2.91-15.3, p<0.001) on multivariate analysis. Among patients with a CACS≤10, men, hypercholesterolemia, and typical angina pectoris were significantly more frequent in patients with than in those without obstructive CAD (p<0.01). Our data suggest that neither the absence nor low of coronary calcium burden may reliably exclude obstructive CAD in typical symptomatic male patients with hypercholesterolemia. This result may be useful to interpret the relation of CACS to obstructive CAD.

Quantification of Coronary Atherosclerosis and Inflammation to Predict Coronary Events and All-Cause Mortality

This study sought to determine whether the evaluation of the combined presence of coronary artery calcium (CAC) and high-sensitivity C-reactive protein (hsCRP) improves discrimination and stratification of hard coronary events and all-cause mortality in the general population. Coronary atherosclerosis is a chronic inflammatory disease. Both hsCRP as a measure of inflammation and CAC as a measure of coronary plaque burden have been shown to improve risk appraisal. Framingham risk variables, hsCRP, and CAC were measured in 3,966 subjects without known coronary artery disease or acute inflammation. After 5 years, incident coronary deaths, nonfatal myocardial infarction, and all-cause mortality were determined. CAC and hsCRP independently predicted 91 coronary events (adjusted hazard ratios [HRs]: log(2)(CAC+1) = 1.25 [95% confidence interval (CI): 1.16 to 1.34], p < 0.0001; hsCRP = 1.11 [95% CI: 1.02 to 1.21], p = 0.019) and 130 deaths (adjusted HRs: log(2)(CAC+1) = 1.12 [95% CI: 1.06 to 1.19], p < 0.0001; hsCRP = 1.11 [95% CI: 1.04 to 1.19], p = 0.004). For coronary events, net reclassification improvement (NRI) was 23.8% (p = 0.0007) for CAC and 10.5% (p = 0.026) for hsCRP. Adding CAC to Framingham risk variables and hsCRP further improved discrimination of coronary risk but not vice versa. Among persons without CAC, those with hsCRP >3 mg/l versus <3 mg/l had a significantly higher coronary risk (p = 0.006). For all-cause mortality, integrated discrimination improvement (IDI) was positive when CAC or hsCRP were added to age and sex (+0.51%, p < 0.001 and +0.43%, p = 0.012, respectively). Adjusted HRs in the highest versus lowest category of a risk index derived from established CAC and hsCRP thresholds (i.e., CAC = 100 and hsCRP = 3 mg/l) were 5.92 (95% CI: 3.14 to 11.16) for coronary events and 3.02 (95% CI: 1.82 to 5.01) for all-cause mortality (p < 0.0001 each). The adjusted HR for coronary events in intermediate risk subjects was 6.98 (95% CI: 2.47 to 19.73), p < 0.001. The risk of coronary events and all-cause mortality that is mediated by the presence of coronary atherosclerosis and systemic inflammation can be estimated by CAC and hsCRP. An improvement in coronary risk prediction and discrimination was predominantly driven by CAC, whereas hsCRP appears to have a role especially in persons with very low CAC scores.

Association between cardiovascular risk factors and the presence of coronary plaque in a zero or low coronary artery calcium score

Association between cardiovascular risk factors and the presence of coronary plaque in a zero or low coronary artery calcium score

Type 2 diabetes does not attenuate racial differences in coronary calcification

Aims Coronary artery calcification (CAC) is a strong predictor of atherosclerotic cardiovascular disease (CVD). Whites appear to have a higher prevalence of CAC than African-Americans (AAs), but it is unknown if type 2 diabetes, a major cardiovascular risk factor, attenuates this difference. We investigated the relationship of race and CAC in a sample of patients with type 2 diabetes without clinical CVD. Methods Multivariable analyses of self-reported ethnicity and CAC scores, stratified by gender, in 861 subjects [32% AA, 66.9% male] with type 2 diabetes. Results AA race was associated with lower CAC scores in age-adjusted models in males [Tobit ratio for AAs vs. Whites 0.14 (95% CI 0.08–0.24, p < 0.001)] and females [Tobit ratio 0.26 (95% CI 0.09–0.77, p = 0.015)]. This persisted in men after adjustment for traditional, metabolic and inflammatory risk factors, but adjustment for plasma triglycerides [0.48 (95% CI 0.15–1.49, p = 0.201)] and HOMA-IR [0.28 (95% CI 0.08–1.03, p = 0.055)] partially attenuated the association in women. Conclusions Relative to African-Americans, White race is a strong predictor of CAC, even in the presence of type 2 diabetes. The relationship in women appears less robust possibly due to gender differences in metabolic risk factors.