Influence of Differential Calcification in the Descending Thoracic Aorta on Aortic Pulse Pressure

Validity of Atherosclerotic Calcified Lesions Observed on Low-Dose Computed Tomography and Cardio-Ankle Vascular Index as Surrogate Markers of Atherosclerosis Progression

The significance of atherosclerotic calcified lesions observed on low-dose computed tomography (LDCT) performed during general checkups was investigated. The coronary arteries (CA), ascending aorta and aortic arch (AAAA), descending thoracic aorta (DTA), and abdominal aorta (AA) were examined. Semiquantitative calcified index analysis of the DTA and AA in terms of atherosclerosis risk factors and cardio-ankle vascular index (CAVI) measurements was also performed. We included 1594 participants (mean age: 59.2 years; range: 31-91 years). The prevalence of calcified lesions was 71.0%, 66.6%, 57.2%, and 37.9% in the AA, CA, AAAA, and DTA, respectively. Age-related advances in calcification among participants with no major risk factors, revealed that calcification appeared earliest in the AA, followed by the CA, AAAA, and DTA. Participants with calcified lesions in all arteries had a significantly greater CAVI than those without calcification. The CAVI was negatively correlated with low-density lipoprotein cholesterol levels, particularly in participants without calcified lesions in the DTA. Calcified lesions on LDCT could indicate the end stage of atherosclerotic lesions. The CAVI can be used to assess atherosclerotic changes at all stages of disease progression. A combination of LDCT and CAVI could be used as a routine non-invasive assessment of atherosclerosis.

Favorable Cardiovascular Health Is Associated With Lower Prevalence, Incidence, Extent, and Progression of Extracoronary Calcification: MESA

BACKGROUND

Ideal cardiovascular health (CVH) is associated with a lower incidence of cardiovascular disease. Extracoronary calcification (ECC)-measured at the aortic valve, mitral annulus, ascending thoracic aorta, and descending thoracic aorta-is an indicator of systemic atherosclerosis. This study examined whether favorable CVH was associated with a lower risk of ECC.

METHODS

We analyzed data from MESA (Multi-Ethnic Study of Atherosclerosis) participants aged 45 to 84 years without cardiovascular disease at baseline. ECC was measured by noncontrast cardiac computed tomography scan at baseline and after an average of 2.4 years. Prevalent ECC was defined as an Agatston score >0 at the baseline scan. Incident ECC was defined as Agatston score >0 at the follow-up scan among participants with Agatston score of 0 at the baseline scan. Each CVH metric (smoking, physical activity, body mass index, diet, blood pressure, total cholesterol, and blood glucose) was scored 0 to 2 points, with 2 indicating ideal; 1, intermediate; and 0, poor. The aggregated CVH score was 0 to 14 points (0-8, inadequate; 9-10, average; 11-14, optimal). We used Poisson and linear mixed-effects regression models to examine the association between CVH and ECC adjusted for sociodemographic factors.

RESULTS

Of 6504 participants, 53% were women with a mean age (SD) of 62 (10) years. Optimal and average CVH scores were associated with lower ECC prevalence, incidence, and extent. For example, optimal CVH scores were associated with 57%, 56%, 70%, and 54% lower risk of incident aortic valve calcification, mitral annulus calcification, ascending thoracic aorta calcification, and descending thoracic aorta calcification, respectively. In addition, optimal and average CVH scores were associated with lower ECC progression at 2 years, although these associations were only significant for mitral annulus calcification and descending thoracic aorta calcification.

CONCLUSIONS

In this multiethnic cohort, favorable CVH was associated with a lower risk of extracoronary atherosclerosis. These findings emphasize the importance of primordial prevention as an intervention to reduce the burden of cardiovascular disease.

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.

Multiaxial pulsatile dynamics of the thoracic aorta and impact of thoracic endovascular repair

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Altered motion of the thoracic aorta after thoracic endovascular aortic repair.

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Geometric analysis with cardiac-gated computed tomography and computer modeling.

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Decreased motion of the stented aorta and increased motion above the stented aorta.

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Longitudinal curvature and diametric deformation affected by presence of endograft.

Purpose

The thoracic aorta is a highly mobile organ whose dynamics are altered by thoracic endovascular aorta repair (TEVAR). The aim of this study was to quantify cardiac pulsatility-induced multi-axial deformation of the thoracic aorta before and after descending aortic TEVAR.

Methods

Eleven TEVAR patients (8 males and 3 females, age 57–89) underwent retrospective cardiac-gated CT angiography before and after TEVAR. 3D geometric models of the thoracic aorta were constructed, and lumen centerlines, inner and outer surface curves, and cross-sections were extracted to measure aortic arclength, centerline, inner surface, and outer surface longitudinal curvatures, as well as cross-sectional effective diameter and eccentricity for the ascending and stented aortic portions.

Results

From pre- to post-TEVAR, arclength deformation was increased at the ascending aorta from 5.9 ± 3.1 % to 8.8 ± 4.4 % (P < 0.05), and decreased at the stented aorta from 7.5 ± 5.1 % to 2.7 ± 2.5 % (P < 0.05). Longitudinal curvature and diametric deformations were reduced at the stented aorta. Centerline curvature, inner surface curvature, and cross-sectional eccentricity deformations were increased at the distal ascending aorta.

Conclusions

Deformations were reduced in the stented thoracic aorta after TEVAR, but increased in the ascending aorta near the aortic arch, possibly as a compensatory mechanism to maintain overall thoracic compliance in the presence of reduced deformation in the stiffened stented aorta.