Extensive thoracic aortic calcification is an independent predictor of development of coronary artery calcium among individuals with coronary artery calcium score of zero

Segmental Evaluation of Thoracic Aortic Calcium and Their Relations with Cardiovascular Risk Factors in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

Thoracic aortic calcium (TAC) appears to be a subclinical marker of cardiovascular disease (CVD) and to predict cardiovascular (CV) mortality. However, studies on TAC use tomographic scans obtained for coronary artery calcium (CAC) score, which does not include the aortic arch. This study evaluates TAC prevalence in aortic arch (AAC), ascending (ATAC) and descending thoracic aorta (DTAC) and verify whether they are associated with the same CV risk factors. Cross-sectional analysis, including 2427 participants (mean age 55.6 ± 8.7; 54.1% women) of the ELSA-Brasil cohort. Nonenhanced ECG-gated tomographies were performed in 2015–2016. Multivariable logistic regression estimated the CV risk factors associated with calcium in each segment. Overall prevalence of ATAC, AAC and DTAC was, 23.1%, 62.1%, and 31.2%, respectively. About 90.4% of the individuals with TAC had AAC and only 19.5% had calcium in all segments. In the multivariable analysis, increasing age, lower levels of schooling, current smoking, higher body mass index, and hypertension remained associated with calcium in all segments. No sex or race/ethnicity differences were found in any aortic segment. Diabetes and dyslipidemia were associated with ATAC and DTAC, but not with AAC, suggesting that AAC may reflect an overlap of mechanisms that impact vascular health, including atherosclerosis.

Association of progressive thoracic aortic calcification with future cardiovascular events and all-cause mortality: ability to improve risk prediction? Results of the Heinz Nixdorf Recall (HNR) study

AIMS

Thoracic aortic calcification (TAC) is measured by computed tomography (CT). We investigated the association of TAC-progression with incident cardiovascular (CV) events and all-cause mortality in a population-based cohort and to determine its predictive value for these endpoints.

METHODS AND RESULTS

In 3080 participants (45-74 years, 53.6% women), risk factors and TAC via CT were measured at baseline and at a second examination after 5.1 ± 0.3 years. Hard coronary, hard CV events as well as CV events including revascularization and all-cause mortality were recorded during a follow-up time of 7.8 ± 2.2 years after the second CT scan. Cox regression analysis determined the association of TAC-progression with observed endpoints. The predictive value of TAC-progression was assessed using Harrell's C index. We observed 81 hard coronary, 154 hard CV, 231 CV events including revascularization, and 266 deaths. In the crude analysis, event rates increased continuously with the level of TAC-change over 5 years for all endpoints. After adjustment, the significant association of TAC-progression with hard CV events [hazard ratio (HR) 1.28, 95% confidence interval (CI) 1.05-1.57] and all-cause mortality (HR 1.34, 95% CI 1.14-1.58) persisted, per one standard deviation increase in TAC-progression (log(TAC + 1)). Regarding aortic segments separately, HRs were consistently higher for descending thoracic aorta. When adding TAC (baseline and progression) to the model containing classical risk factors and coronary artery calcification (CAC), Harrell's C indices did not increase for any of the observed endpoints.

CONCLUSION

TAC-progression is associated with incident hard CV events and all-cause mortality but fails to improve event prediction over CAC.

Should Radiologists Comment on Incidental Findings of Vascular Calcifications Found on Abdominal/Pelvic CT in Patients Less Than 50 Years of Age?

RATIONALE AND OBJECTIVES

To evaluate if incidental abdominopelvic calcified atherosclerosis (ACA) in patients under 50 years of age correlates with cardiovascular disease (CVD) risk factors. Most studies evaluating calcific atherosclerosis and associated increased risk of CVD have concentrated on middle age and older populations.

MATERIALS AND METHODS

A retrospective review of 519 emergency department patients, aged 25-50 years, receiving computed tomography (CT) was performed and ACA correlated with lipid panels obtained via chart review. Those with calcified atherosclerosis were subdivided by vessel location and calcification burden (mild, moderate, or severe). Patients were followed for six years. Normality, Wilcoxon-Mann-Whitney, Kruskal-Wallis, and chi-square tests were performed.

RESULTS

Two hundred and sixty-nine patients with incidental ACA on CT and 250 without ACA were studied. Atherosclerotic calcifications had a statistically significant correlation with elevated triglyceride (128 mg/dL vs 105 mg/dL; p = 0.0003) and decreased high-density lipoprotein (38 mg/dL vs 41 mg/dL; p = 0.0032) as compared to the control. Patients with ACA were at higher risk of stroke, heart attack, and death (p < 0.0001) during a six-year follow-up period.

CONCLUSION

Incidental atherosclerotic calcification on abdominopelvic CT in patients under 50 years of age correlated with elevated triglycerides and decreased high-density lipoprotein as well as higher risk of cardiovascular events. Since radiologists may be the first to identify this finding and CVD is the leading cause of US deaths, proper recognition and reporting of calcification is valuable.

Thoracic aortic calcification across the clinical dysglycemic continuum in a large Asian population free of cardiovascular symptoms

Thoracic aortic calcification (TAC) is tightly linked to pathological atherosclerosis and associated with certain cardiovascular diseases. While diabetes mellitus (DM) is known as a coronary heart disease equivalent, we examined the presence of TAC across the dysglycemic spectrum of diabetes mellitus (DM). We consecutively studied 3003 asymptomatic ethnic Asians underwent annual cardiovacular health survey, and further categorized them into: 1) 1760 normo-glycemic, 2) 968 pre-diabetic, and 3) 274 overt DM based on dysglycemic indices and medical histories. Several TAC parameters were assessed using non-contrast multi-detector computed tomography (MDCT), and related to dysglycemic indices or diabetes mellitus status. A remarkably graded increases of adjusted total TAC calcium burden, volume and density were seen across Non-diabetes, Pre-diabetes, and diabetes mellitus categories and positively correlated with all dysglycemic profiles (all p<0.001). Multi-variate logistic and linear regression models demonstrated independent associations between greater TAC density and all dysglycemic indices (Coef: 2.5, 1.4, 6.8 for fasting, postprandial sugar and HbA1c) and diabetes mellitus status (all p<0.05). Furthermore, Receiver-operating characteristic curves (ROC) showed fasting sugar and postprandial sugar set at 103mg/dL and 111mg/dL, separately, with HbA1c set at 5.8% all predict the presence of aortic calcification. Dysglycemic status, even without overt diabetes mellitus, were tighly linked to subclinical, pathological thoracic aortic calcification.

GOLD stage predicts thoracic aortic calcifications in patients with COPD

Although some of the associations between chronic obstructive pulmonary disease (COPD) and atherosclerosis are based on shared risk factors such as smoking, recent epidemiological evidence suggests that COPD is a risk factor for vascular disease due to systemic inflammation. The present study assessed the hypothesis that disease severity (as expressed by the GOLD stage) independently predicts the extent of vascular calcifications. A total of 160 smokers diagnosed with COPD (GOLD I-IV, 40 subjects of each GOLD stage) and 40 smokers at risk (GOLD 0; median age of 60 years old; Q1:56;Q3:65; 135 males and 65 females) underwent non-contrast, non-electrocardiography synchronized chest computerised tomography. The volume of thoracic aortic calcifications was quantified semi-automatically within a region from T1 through T12. Multiparametric associations with GOLD stage, smoking history, sex, age, body mass index and emphysema index were evaluated using generalized linear regression analysis. Thoracic aortic calcifications were highly prevalent in this cohort (187/200 subjects, 709 (Q1:109;Q3:2163) mm³). Analysis of variance on ranks demonstrated a significant difference in calcium between different GOLD-stages as well as patients at risk of COPD (F=36.8, P<0.001). In the multivariable analysis, GOLD-stages were indicated to be predictive of thoracic aortic calcifications (P≤0.0033) besides age (P<0.0001), while age appeared to be the strongest predictor. Other variables were not statistically linked to thoracic aortic calcifications in the multivariable model. COPD severity, as expressed by the GOLD-stage, is a significant predictor of thoracic aortic calcifications, independent of covariates such as age or tobacco consumption.

Aortic Calcification Onset and Progression: Association With the Development of Coronary Atherosclerosis

Background

Thoracic aortic calcification (TAC) and coronary artery calcification (CAC) are markers of subclinical atherosclerosis and are associated with incident major cardiovascular events. We investigated major determinants for incidence and progression of TAC and the association between TAC and CAC incidence and progression.

Methods and Results

In a population‐based cohort study, 3270 participants (aged 45–74 years, 53.1% women) received cardiac computed tomography at baseline and after a mean follow‐up of 5.1±0.3 years for quantification of calcification of the ascending (ATAC) and descending thoracic aorta (DTAC) and CAC. Multivariable relative risk regression analysis was used to investigate associations of cardiovascular risk factors with incident TAC, of baseline TAC with incident CAC, and of baseline CAC with incident TAC. Of 1243 participants with baseline TAC of 0, 517 (41.6%) revealed incident TAC after 5 years. Incidence of descending TAC was higher (34.5%) than ascending TAC (23.3%). Incident TAC after 5 years was associated with age (relative risk 1.26 [95% CI 1.21–1.33], per 5 years), blood pressure (relative risk 1.06 [95% CI 1.03–1.10], per 10 mm Hg), low‐density lipoprotein cholesterol (relative risk 1.08 [95% CI 1.04–1.12], per 20 mg/dL), and smoking (relative risk 1.28 [95% CI 1.07–1.53]). Among the 1185 participants without CAC at baseline, the risk of developing CAC was 28.3% when baseline TAC was present compared with 22.2% among those without baseline TAC (excess risk 6.1% [95% CI 1.2–11.0%]). The point estimate of excess risk for incident CAC was higher for ascending TAC (10.8% [95% CI 4.8–16.7%]) and low for descending TAC (1.8% [95% CI −3.2% to 6.7%]). Excess risk for developing ascending and descending TAC with present baseline CAC was 16.4% (95% CI 12.7–20.0%) and 15.6% (95% CI 10.8–20.4%), respectively.

Conclusion

TAC and CAC share similar major determinants for incident calcification. Participants with TAC, especially ascending TAC, are at elevated risk for development of CAC.

Aortic Valve and Thoracic Aortic Calcification Measurements: How Low Can We Go in Radiation Dose?

OBJECTIVE

This study aimed to determine the lowest radiation dose and iterative reconstruction level(s) at which computed tomography (CT)-based quantification of aortic valve calcification (AVC) and thoracic aortic calcification (TAC) is still feasible.

METHODS

Twenty-eight patients underwent a cardiac CT and 20 patients a chest CT at 4 different dose levels (routine dose and approximately 40%, 60%, and 80% reduced dose). Data were reconstructed with filtered back projection, 3 iDose levels, and 3 iterative model-based reconstruction levels. Two observers scored subjective image quality. The AVC and TAC were quantified using mass and compared to the reference scan (routine dose reconstructed with filtered back projection).

RESULTS

In cardiac CT at 0.35 mSv (60% reduced), all scans reconstructed with iDose (all levels) were diagnostic, calcification detection errors occurred in only 1 patient, and there were no significant differences in mass scores compared to the reference scan. Similar results were found for chest CT at 0.48 mSv (75% reduced) with iDose levels 4 and 6 and iterative model reconstruction levels 1 and 2.

CONCLUSIONS

Iterative reconstruction enables AVC and TAC quantification on CT at submillisievert dose.

Correlation between thoracic aorta 18F-natrium fluoride uptake and cardiovascular risk

AIM: To investigating the relationship between thoracic and cardiac ¹⁸F-Natrium-Fluoride (18F-NaF) uptake, as a marker of ongoing calcification and cardiovascular risk factors.

METHODS: Seventy-eight patients (44 females, mean age 63, range 44-83) underwent whole body 18F-NaF positron emission tomography/computed tomography. Cardiovascular risk (CVR) was used to divide these patients in three categories: Low (LR), medium (MR) and high risk (HR). 18F-NaF uptake was measured by manually drawing volumes of interest on the ascending aorta, on the aortic arch, on the descending aorta and on the myocardium; average standardized uptake value was normalized for blood-pool, to obtain target-to-background ratio (TBR). Values from the three aortic segments were then averaged to obtain an index of the whole thoracic aorta.

RESULTS: A significant difference in whole thoracic aorta TBR was detected between HR and LR (1.84 ± 0.76 vs 1.07 ± 0.3, P < 0.001), but also between MR and HR-LR (1.4 ± 0.4, P < 0.02 and P < 0.01, respectively). Significance of this TBR stratification strongly varied among thoracic aorta subsegments and the lowest P values were reached in the descending aorta (P < 0.01). Myocardial uptake provided an effective CVR classes stratification (P < 0.001).Correlation between TBR and CVR was appreciable when the whole thoracic aorta was considered (R = 0.67), but it peaked when correlating the descending thoracic segment (R = 0.75), in comparison with the aortic arch and the ascending segment (R = 0.55 and 0.53, respectively).

CONCLUSION: Fluoride uptake within the thoracic aorta wall effectively depicts patients’ risk class and correlates with cardiovascular risk. Descending aorta is the most effective in CVR determination.