Abdominal aortic atherosclerosis at MR imaging is associated with cardiovascular events: the Dallas heart study

Association Between Aortic Wall Parameters on Multidetector Computed Tomography and Ruptured Plaques By Nonobstructive General Angioscopy

BACKGROUND

Nonobstructive general angioscopy (NOGA) can identify vulnerable plaques in the aortic lumen that serve as potential risk factors for cardiovascular events such as embolism. However, the association between computed tomography (CT) images and vulnerable plaques detected on NOGA remains unknown.

METHODS AND RESULTS

We investigated 101 patients (67±11 years; women, 13.8%) who underwent NOGA and contrast-enhanced CT before or after 90 days in our hospital. On CT images, the aortic wall thickness, aortic wall area (AWA), and AWA in the vascular area were measured at the thickest point from the 6th to the 12th thoracic vertebral levels. Furthermore, the association between these measurements and the presence or absence of NOGA-derived aortic plaque ruptures (PRs) at the same vertebral level was assessed. NOGA detected aortic PRs in the aortic lumens at 145 (22.1%) of the 656 vertebral levels. The presence of PRs was significantly associated with greater aortic wall thickness (3.3±1.7 mm versus 2.1±1.2 mm), AWA (1.33±0.68 cm2 versus 0.89±0.49 cm2), and AWA in the vascular area (23.2%±9.3% versus 17.2%±7.6%) (P<0.001 for all) on the CT scans compared with the absence of PRs. The frequency of PRs significantly increased as the aortic wall thickness increased. Notably, a few NOGA-derived PRs were detected on CT in near-normal intima.

CONCLUSIONS

The presence of NOGA-derived PRs was strongly associated with increased aortic wall thickness, AWA, and AWA in the vascular area, measured using CT. NOGA can detect PRs in the intima that appear almost normal on CT scans.

Nicotine dependence and visceral adiposity as risk factors for the development and severity of carotid artery stenosis

Nicotine dependence (ND) and visceral adiposity are emerging as independent risk factors for cardiovascular diseases, including carotid artery stenosis (CAS). This study aimed to determine the relationship between ND and the contribution of abdominal fat to the onset of CAS, which is indicated by a luminal narrowing of at least 60% as determined by duplex and/or Doppler ultrasound. We prospectively collected data from 60 patients with CAS and 60 age- and gender-matched healthy subjects. The Fagerström Test for Nicotine Dependence (FTND), a common research tool, was used in the study. The original questionnaire was designed to gather social and demographic data. Anthropometric measurements, visceral adiposity index (VAI), and lipid accumulation products (LAP) were used to assess obesity. Most patients showed a high or mild-moderate degree of ND: 46.67% and 35%, respectively. The median visceral adiposity index (VAI) and lipid accumulation product (LAP) in patients was 3.92 and 32.83, respectively. Prolonged smoking duration, increased intensity, and high ND are hallmarks of CAS patients.

Prevalence and distribution of aortic plaque by sex and age group among community-dwelling adults

RATIONALE AND OBJECTIVES

Atherosclerosis of the aorta is associated with increased risk of cardiovascular mortality and vascular events. We aim to describe the prevalence and distribution of non-calcified atherosclerotic plaque in the descending aorta as quantified by noncontrast cardiovascular magnetic resonance (CMR) in a community-dwelling cohort of adults.

MATERIALS AND METHODS

We used CMR to quantify noncalcified aortic plaque in 1726 participants (aged 65 ± 9 years, 46.7% men) from the Cohort Study Offspring cohort. ECG-gated, fat-suppressed, T2-weighted, black blood turbo spin echo sequence was used to acquire 36 transverse slices covering the descending aorta from just below the arch to the aortoiliac bifurcation. Plaque was defined as discrete luminal protrusions ≥1 mm; these were manually traced, then summed to determine total descending aortic plaque (DAP) and segmental thoracic and abdominal aortic plaque (TAP, AAP). Participants were stratified by sex and age group (<55, 55-64, 65-74, ≥75y). A healthy referent group (without clinical cardiovascular disease, smoking, diabetes, impaired renal function; (N = 768, 43.8% men) was used to determine upper 90th percentile cutpoints for DAP and AAP which were then applied to the overall study cohort.

RESULTS

Prevalence of DAP was similar between men (47.3%) and women (48.9%), p = 0.50, as was AAP prevalence (men: 44.5%, women: 46.7%, p = 0.16); TAP was less prevalent in both sexes (men: 8.9%, women: 7.1%, p = 0.15). Both prevalence and burden of DAP, AAP and TAP increased with advancing age.

CONCLUSION

Noncalcified plaque prevalence, visualized on CMR, in community-dwelling adults is similar between the sexes, and both prevalence and burden of aortic plaque increase with greater age.

Relation of MRI Aortic Wall Area and Plaque to Incident Cardiovascular Events: The Framingham Heart Study

Background Arterial arteriosclerosis and atherosclerosis reflect vascular disease, the subclinical detection of which allows opportunity for cardiovascular disease (CVD) prevention. Larger cohort studies simultaneously quantifying anatomic thoracic and abdominal aortic pathologic abnormalities are lacking in the literature. Purpose To investigate the association of aortic wall area (AWA) and atherosclerotic plaque presence and burden as measured on MRI scans with incident CVD in a community sample. Materials and Methods In this prospective cohort study, participants in the Framingham Heart Study Offspring Cohort without prevalent CVD underwent 1.5-T MRI (between 2002-2005) of the descending thoracic and abdominal aorta with electrocardiogram-gated axial T2-weighted black-blood acquisitions. The wall thickness of the thoracic aorta was measured at the pulmonary bifurcation level and used to calculate the AWA as the difference between cross-sectional vessel area and lumen area. For primary or secondary analyses, multivariable Cox proportional hazards regression models were used to examine the association of aortic MRI measures with risk of first-incident CVD events or stroke and coronary heart disease, respectively. Results In 1513 study participants (mean age, 64 years ± 9 [SD]; 842 women [56%]), 223 CVD events occurred during follow-up (median, 13.1 years), of which 97 were major events (myocardial infarction, ischemic stroke, or CVD death). In multivariable analysis, thoracic AWA and prevalent thoracic plaque were associated with incident CVD (hazard ratio [HR], 1.20 per SD unit [95% CI: 1.05, 1.37] [P = .006] and HR, 1.63 [95% CI: 1.12, 2.35] [P = .01], respectively). AWA and prevalent thoracic plaque were associated with increased hazards: 1.32 (95% CI: 1.07, 1.62; P = .01) and 2.20 (95% CI: 1.28, 3.79; P = .005), for stroke and coronary heart disease, respectively. Conclusion In middle-aged community-dwelling adults, thoracic aortic wall area (AWA), plaque prevalence, and plaque volumes measured with MRI were independently associated with incident cardiovascular disease, with AWA associated in particular with stroke, and plaque associated with coronary heart disease. Clinical trial registration no. NCT00041418 © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Peshock in this issue.

GlycA, hsCRP differentially associated with MI, ischemic stroke: In the Dallas Heart Study and Multi-Ethnic Study of Atherosclerosis: GlycA, hsCRP Differentially Associated MI, Stroke

Objective

Inflammatory markers are associated with cardiovascular disease (CVD); however, the ability to specifically predict myocardial infarction (MI) as well as ischemic stroke remains unknown. There has not been a direct comparison of the associations between GlycA and hsCRP and MI and ischemic stroke in a multi-ethnic pooled cohort.

Methods

Multi-center, multi-ethnic, population-based community prospective pooled cohort of the Dallas Heart Study (DHS) and Multi-Ethnic Study of Atherosclerosis (MESA). 9,785 participants without baseline CVD enrolled with median follow-up of 13.4 years. Fatal/nonfatal MI and fatal/nonfatal ischemic stroke were assessed separately and then combined.

Results

GlycA was moderately associated with hsCRP (R=0.58 in DHS and R=0.55 in MESA). In adjusted Cox proportional hazards models with competing risk adjusted for both inflammatory markers, GlycA was directly associated with MI (HR Q4 vs. Q1 1.90, 95% CI 1.39 to 2.58), whereas hsCRP was not (HR Q4 vs. Q1 0.92, 95% CI 0.70 to 1.21). Conversely, hsCRP was directly associated with ischemic stroke (HR Q4 vs. Q1 1.73, 95% CI 1.15 to 2.59), but GlycA was not (HR Q4 vs. Q1 1.21, 95% CI 0.77 to 1.90). GlycA improved net reclassification for MI and hsCRP did so for ischemic stroke.

Conclusions

Although both GlycA and hsCRP were associated with incident CVD, GlycA more strongly predicted incident MI, and hsCRP more strongly predicted ischemic stroke.

Maternal dietary fatty acid composition and newborn epigenetic aging-a geometric framework approach

BACKGROUND

Maternal nutrition is associated with epigenetic and cardiometabolic risk factors in offspring. Research in humans has primarily focused on assessing the impact of individual nutrients.

OBJECTIVES

We sought to assess the collective impact of maternal dietary MUFAs, PUFAs, and SFAs on epigenetic aging and cardiometabolic risk markers in healthy newborn infants using a geometric framework approach.

METHODS

Body fatness (n = 162), aortic intima-media thickness (aIMT; n = 131), heart rate variability (n = 118), and epigenetic age acceleration (n = 124) were assessed in newborn infants. Maternal dietary intake was cross-sectionally assessed in the immediate postpartum period via a validated 80-item self-administered FFQ. Generalized additive models were used to explore interactive associations of nutrient intake, with results visualized as response surfaces.

RESULTS

After adjustment for total energy intake, maternal age, gestational age, and sex there was a 3-way interactive association of MUFAs, PUFAs, and SFAs (P = 0.001) with newborn epigenetic aging. This suggests that the nature of each fat class association depends upon one another. Response surfaces revealed MUFAs were positively associated with newborn epigenetic age acceleration only at proportionately lower intakes of SFAs or PUFAs. We also demonstrate a potential beneficial association of omega-3 (n-3) PUFAs with newborn epigenetic age acceleration (P = 0.008). There was no significant association of fat class with newborn aIMT, heart rate variability, or body fatness.

CONCLUSIONS

In this study, we demonstrated an association between maternal dietary fat class composition and epigenetic aging in newborns. Future research should consider other characteristics such as the source of maternal dietary fatty acids.

Aortic plaque burden predicts vascular events in patients with cardiovascular disease: The EAST-NOGA study

BACKGROUND

Non-obstructive general angioscopy (NOGA) can be used to diagnose aortic atherosclerotic plaques. We examine the association between the number of aortic plaques detected by NOGA and the risk of subsequent cardiovascular events.

METHODS

The Evaluation of AtheroScleroTic and rupture events by Non-Obstructive General Angioscopy (EAST-NOGA) was a prospective cohort study of patients with suspected coronary artery disease who underwent NOGA.

RESULTS

Of the 577 patients who underwent NOGA, 532 (92%) completed the follow-up (median follow-up: 13 months, interquartile range: 12-16). The median number of plaques per person was 6 (interquartile range: 3-12), and 567 (98%) had at least one aortic plaque. During the 13-month follow-up, 38 (7.1%) patients had a primary composite endpoint [including cardiovascular death, myocardial infarction, stroke, peripheral artery disease (PAD), or worsening renal function], which was significantly associated with chronic kidney disease, a history of PAD, a lower hemoglobin level, and large numbers of aortic plaques [11 (5-17) vs. 6 (2-11), p = 0.003]. A receiver operating characteristic curve analysis for the number of aortic plaques predicting composite endpoints revealed that the cut-off value of aortic plaques was 12. After multivariate adjustment, the presence of ≥12 aortic plaques remained a significant predictor for composite endpoint events (hazard ratio 2.53, 95% confidence interval 1.26-5.04, p = 0.010).

CONCLUSIONS

The number of aortic plaques detected by NOGA may predict subsequent clinical events.

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.

From Psoriasis to Psoriatic Arthritis: Insights from Imaging on the Transition to Psoriatic Arthritis and Implications for Arthritis Prevention

PURPOSE OF REVIEW

To describe the recent advances in the field towards the prevention and early recognition of Psoriatic Arthritis (PsA).

RECENT FINDINGS

Defining the preclinical phase of PsA remains challenging since up to 50% of subjects with psoriasis have subclinical imaging enthesopathy, but many of these do not progress to PsA. Nevertheless, there is evidence that subjects with subclinical imaging enthesopathy are at increased risk of developing PsA. In recent years, it has been shown that both PsA and anti-citrullinated protein antibodies (ACPA) positive rheumatoid arthritis (RA) are characterized by a subclinical phase of non-specific or brief duration arthralgia with shared imaging features accounting for joint symptomatology. Sonographically determined tenosynovitis and enthesitis are the key imaging features present in non-specific PsO arthralgia that are at risk of future PsA development. Furthermore, the early phases of PsA are complicated by factors including body mass index (BMI), which is a risk factor for PsA, but BMI is also associated with imaging abnormalities on enthesopathy. Fully disentangling these clinical and imaging factors will be important for enrichment for imminent PsA so that disease prevention strategies can be investigated. Psoriasis patients with arthralgia have a higher prevalence of tenosynovitis and imaging enthesopathy is at higher risk of transitioning to overt PsA.

Impaired HDL Metabolism Links GlycA, A Novel Inflammatory Marker, with Incident Cardiovascular Events

High-density lipoproteins (HDL) exert anti-atherosclerotic effects via reverse cholesterol transport, yet this salutary property is impaired in the setting of inflammation. GlycA, a novel integrated glycosylation marker of five acute phase reactants, is linked to cardiovascular (CV) events. We assessed the hypothesis that GlycA is associated with measures of impaired HDL function and that dysfunctional HDL may contribute to the association between GlycA and incident CV events. Baseline measurements of HDL cholesterol (HDL-C), HDL particle concentration (HDL-P), apoliprotein A1 (Apo A1), cholesterol efflux capacity, GlycA and high-sensitivity C-reactive protein (hs-CRP) were obtained from the Dallas Heart Study, a multi-ethnic cohort of 2643 adults (median 43 years old; 56% women, 50% black) without cardiovascular disease (CVD). GlycA was derived from nuclear magnetic resonance imaging. Participants were followed for first nonfatal MI, nonfatal stroke, coronary revascularization, or CV death over a median of 12.4 years (n = 197). The correlation between GlycA and hs-CRP was 0.58 (p < 0.0001). In multivariate models with HDL-C, GlycA was directly associated with HDL-P and Apo A1 and inversely associated with cholesterol efflux (standardized beta estimates: 0.08, 0.29, -0.06, respectively; all p ≤ 0.0004) GlycA was directly associated with incident CV events (adjusted hazard ratio (HR) for Q4 vs. Q1: 3.33, 95% confidence interval (CI) 1.99, 5.57). Adjustment for cholesterol efflux mildly attenuated this association (HR for Q4 vs. Q1: 3.00, 95% CI 1.75 to 5.13). In a multi-ethnic cohort, worsening inflammation, as reflected by higher GlycA levels, is associated with higher HDL-P and lower cholesterol efflux. Impaired cholesterol efflux likely explains some of the association between GlycA and incident CV events. Further studies are warranted to investigate the impact of inflammation on HDL function and CV disease.

Natural History of Atherosclerosis and Abdominal Aortic Intima-Media Thickness: Rationale, Evidence, and Best Practice for Detection of Atherosclerosis in the Young

Atherosclerosis underlies most myocardial infarctions and ischemic strokes. The timing of onset and the rate of progression of atherosclerosis differ between individuals and among arterial sites. Physical manifestations of atherosclerosis may begin in early life, particularly in the abdominal aorta. Measurement of the abdominal aortic intima-media thickness by external ultrasound is a non-invasive methodology for quantifying the extent and severity of early atherosclerosis in children, adolescents, and young adults. This review provides an evidence-based rationale for the assessment of abdominal aortic intima-media thickness-particularly as an age-appropriate methodology for studying the natural history of atherosclerosis in the young in comparison to other methodologies-establishes best practice methods for assessing abdominal aortic intima-media thickness, and identifies key gaps in the literature, including those that will identify the clinical relevance of this measure.

Association of aortic vascular uptake of 18FDG by PET/CT and aortic wall thickness by MRI in psoriasis: a prospective observational study

BACKGROUND

The contribution of inflammation to the incidence of cardiovascular disease (CVD) has been increasingly recognized in recent years. We investigated the relationship of aortic vascular uptake of 18F-FDG by PET/CT and aortic wall thickness (AWT) by MRI in psoriasis, a chronic inflammatory disease with increased incidence of CVD. One hundred sixty-five patients with plaque psoriasis participated in an ongoing longitudinal cohort study. Subclinical atherosclerosis was assessed as aortic uptake of 18F-FDG by PET/CT reported as target-to-background ratio (TBR) and AWT by MRI reported as maximal thickness.

RESULTS

Patients with psoriasis were middle aged, predominantly male, and had mild CV risk by traditional risk factors. Psoriasis severity as measured by PASI score was a notable determinant of AWT (ρ = 0.20, p = 0.01). Moreover, aortic vascular uptake of 18F-FDG associated with AWT by MRI at baseline in unadjusted analysis (β = 0.27 p = 0.001) and following adjustment for traditional cardiovascular risk factors, waist-to-hip ratio, and statin use (β = 0.21 p = 0.01). Finally, following 1 year of psoriasis treatment, a decrease in aortic vascular uptake of 18F-FDG was associated with a reduction in AWT in fully adjusted models (β = 0.33, p = 0.02).

CONCLUSION

In conclusion, we demonstrate that psoriasis severity and aortic vascular uptake of 18F-FDG in the aorta were associated with AWT. Following treatment of psoriasis, a decrease in aortic vascular uptake of 18F-FDG was associated with a reduction in AWT at 1 year. These findings suggest that aortic vascular uptake of 18F-FDG is associated with early evidence of vascular disease assessed by aortic wall thickness. Prospective studies in larger populations including other inflammatory diseases are warranted.

Diagnostic Thresholds for Blood Pressure Measured at Home in the Context of the 2017 Hypertension Guideline

Most guidelines have recommended lower home blood pressure (BP) threshold when clinic BP threshold of 140/90 mm Hg is used for diagnosis of hypertension. However, home BP thresholds to define hypertension have never been determined in the general population in the United States. We identified home BP thresholds for stage 1 (BP ≥130/80 mm Hg) hypertension using a regression-based approach in the DHS (Dallas Heart Study; n=5768) and the NCMH study (North Carolina Masked Hypertension; n=420). Home BP thresholds were also assessed using outcome-derived approach based on the composite of all-cause mortality or cardiovascular events in the DHS cohort. For this approach, BP thresholds were identified only for systolic BP because diastolic BP was not associated with the outcome. Among untreated participants, the regression-derived thresholds for home BP corresponding to clinic BP for stage 1 hypertension were 129/80 mm Hg in blacks, 130/80 mm Hg in whites, and 126/78 mm Hg in Hispanics, respectively. The results are similar in the North Carolina cohort. The 11-year composite cardiovascular and mortality events corresponding to clinic systolic BP >130 mm Hg were higher in blacks than in whites and Hispanics (13.3% versus 5.98% versus 5.52%, respectively). Using a race/ethnicity-specific composite outcome in the untreated DHS participants, the outcome-derived home systolic BP thresholds corresponding to stage 1 hypertension were 130 mm Hg in blacks, 129 mm Hg in whites, and 131 mm Hg in Hispanics, respectively. Our data based on both regression-derived and outcome approach support home BP threshold of 130/80 mm Hg for diagnosis of hypertension in blacks, whites, and Hispanics.

Brain arterial dilatation modifies the association between extracranial pulsatile hemodynamics and brain perivascular spaces: the Northern Manhattan Study

Pulsatile hemodynamics are associated with brain small perivascular spaces (SPVS). It is unknown whether the stiffness of intermediary arteries connecting the aorta and brain modifies this association. Participants from the Northern Manhattan Study were assessed for SPVS (defined as ≤3 mm T1 voids) and white matter hyperintensity volume (WMH) using MRI. Middle (MCA) and anterior cerebral arterial (ACA) diameters (measured on time-of-flight MRA) and CCA strain (assessed by ultrasound) were used as surrogates of stiffness. Brachial and aortic pulse pressure (PP) and aortic augmentation index (Aix, assessed by applanation tonometry) were used as markers of pulsatility. We tested whether stiffness in intermediary arteries modifies the association between extracranial pulsatility with SPVS and WMH. We found that among 941 participants (mean age 71 ± 9 years, 60% women, 66% Hispanic), the right MCA/ACA diameter was associated with right anterior SPVS (B = 0.177, P = 0.002). Brachial PP was associated with right anterior SPVS (B = 0.003, P = 0.02), and the effect size was bigger with right MCA/ACA diameter in the upper tertile (P = 0.001 for the interaction). The association between right CCA strain and ipsilateral SPVS was modified by MCA/ACA diameter, with the largest effect size in those with ipsilateral MCA/ACA diameter in the upper tertile (P = 0.001 for the interaction). Similar dose-effects and statistical interactions were replicated using aortic AIx or aortic PP. We found no evidence of effect modification between pulsatile measures and WMH by stiffness measures. In summary, pulsatile hemodynamics relate to brain SPVS, and the association is the strongest among individuals with dilated brain arteries.

Nicotine dependence as an independent risk factor for atherosclerosis in the National Lung Screening Trial

Background

Atherosclerosis and COPD are systemic inflammatory diseases that share common risk factors including cigarette smoking. A high level of nicotine dependence is emerging as a recently identified risk factor for pulmonary impairment, chronic obstructive pulmonary disease and tobacco-related cancers. We hypothesized that nicotine dependence is associated with the risk of atherosclerosis in long-term cigarette smokers.

Methods

A nested case-control study was conducted within the National Lung Cancer Screening Trial- American College of Radiology Imaging Network. Cases were defined as having a new diagnosis of any type of atherosclerosis. Controls were matched on a 2:1 basis by age, sex, race, study center, smoking status, years of smoking, and frequency of smoking. Dependence was measured by the time to first cigarette after awakening (TTFC).

Results

The study included 166 cases and 286 controls. Compared to participants who smoked within 5 min after waking, the risk of atherosclerosis for participants who smoked an hour or more after waking was borderline non-significant (odds ratio = 0.49, 95% confidence intervals [CI] 0.23, 1.00). Findings were similar for men and women. For aortic atherosclerosis, the corresponding odds ratio was 0.24 (95% CI 0.08, 0.69). Hypertension was associated with an increased risk and body mass index was associated with a decreased risk of aortic atherosclerosis. The TTFC was unrelated to coronary atherosclerosis.

Conclusions

Compared to smoking immediately after waking, delaying an hour or more reduces the risk of aortic atherosclerosis even among long-term heavy smokers. Possible mechanisms that explain this association are intensity of smoking, inflammation and oxidative stress, and elevated lipid levels.

Does Nonenhanced CT-based Quantification of Abdominal Aortic Calcification Outperform the Framingham Risk Score in Predicting Cardiovascular Events in Asymptomatic Adults?

Purpose To determine if abdominal aortic calcification (AAC) at CT predicts cardiovascular events independent of Framingham risk score (FRS). Materials and Methods For this retrospective study, electronic health records for 829 asymptomatic patients (mean age, 57.9 years; 451 women, 378 men) who underwent nonenhanced CT colonography screening between April 2004 and March 2005 were reviewed for subsequent cardiovascular events; mean follow-up interval was 11.2 years ± 2.8 (standard deviation). Institutional review board approval was obtained. CT-based AAC was retrospectively quantified as a modified Agatston score by using a semiautomated tool. Kaplan-Meier curves and Cox proportional hazards models were used for time-to-event analysis; receiver operating characteristic curves and net reclassification improvement compared predictive abilities of AAC and FRS. Results An index cardiovascular event occurred after CT in 156 (19%) of 829 patients (6.7 years ± 3.5, including heart attack in 39 [5%] and death in 79 [10%]). AAC was higher in the cardiovascular event cohort (mean AAC, 3478 vs 664; P < .001). AAC was a strong predictor of cardiovascular events at both univariable and multivariable Cox modeling, independent of FRS (P < .001). Kaplan-Meier plots showed better separation with AAC over FRS. The area under the receiver operating characteristic curve (AUC) was higher for AAC than FRS at all evaluated time points (eg, AUC of 0.82 vs 0.64 at 2 years; P = .014). By using a cutoff point of 200, AAC improved FRS risk categorization with net reclassification improvement of 35.4%. Conclusion CT-based abdominal aortic calcification was a strong predictor of future cardiovascular events, outperforming the Framingham risk score. This finding suggests a potential opportunistic role in abdominal nonenhanced CT scans performed for other clinical indications. © RSNA, 2018.

Applying the ordinal model of atherosclerosis to imaging science: a brief review

Atherogenesis has been well demonstrated to proceed in an ordinal fashion. Imaging technologies have advanced substantially in recent decades, enabling early detection of atherosclerosis. Some modalities, such as coronary CT, have seen broad clinical adaptation. In contrast, others, such as flow-mediated dilatation, remain predominantly research-based. Optimal and appropriate usage of these technologies remains an area of active investigation. We hypothesise that investigators ought to consider which stage of atherosclerosis is under investigation when choosing imaging modalities. Additionally, when assessing the efficacy of a particular treatment, some imaging modalities may be more appropriate than others. We review the most important available imaging modalities and suggest stages at which each may or may not be well used. Conceptual application of the classic stages of atherosclerosis model to the variety of modern imaging modalities available will result in more effective investigation and treatment of cardiovascular disease.

Ex vivo vessel wall thickness measurements of the human circle of Willis using 7T MRI

BACKGROUND AND AIMS

MRI can detect intracranial vessel wall thickening before any luminal stenosis is present. Apart from representing a vessel wall lesion, wall thickening could also reflect normal (age-related) variations in vessel wall thickness present throughout the intracranial arterial vasculature. The aim of this study was to perform vessel wall thickness measurements of the major intracranial arteries in ex vivo circle of Willis (CoW) specimens using 7T MRI, to obtain more detailed information about wall thickness variations of the intracranial arteries.

METHODS

Fifteen human CoW specimens were scanned at 7T MRI with an ultrahigh-resolution T₁-weighted sequence. Five specimens were used for validation of MRI measurements with histology and evaluation of inter-rater reliability and agreement. The other 10 specimens from patients with (n = 5) and without (n = 5) cerebrovascular disease were used for vessel wall thickness measurements over the entire length of the major arterial segments of the CoW using MRI only.

RESULTS

MRI measurements showed excellent agreement with histology. Mean wall thickness varied from 0.45 to 0.66 mm, minimum wall thickness from 0.31 to 0.42 mm, maximum wall thickness from 0.52 to 0.86 mm, and normalized wall index from 0.64 to 0.75. On average, vessel walls were thicker for symptomatic patients compared to asymptomatic patients.

CONCLUSIONS

High-resolution MRI enables accurate measurement of vessel wall thickness in ex vivo CoW specimens. Vessel wall thickness measurements over the entire length of segments showed considerable variation both within and between arterial segments of patients.

Soluble endothelial cell-selective adhesion molecule and incident cardiovascular events in a multiethnic population

BACKGROUND

Cell adhesion molecules are key regulators of atherosclerotic plaque development, but circulating levels of soluble fragments, such as intercellular adhesion molecule (sICAM-1) and vascular cell adhesion molecule (sVCAM-1), have yielded conflicting associations with atherosclerotic cardiovascular disease (ASCVD). Endothelial cell-selective adhesion molecule (ESAM) is expressed exclusively in platelets and endothelial cells, and soluble ESAM (sESAM) levels have been associated with prevalent subclinical atherosclerosis. We therefore hypothesized that sESAM would be associated with incident ASCVD.

METHODS

sESAM, sICAM-1, and sVCAM-1 were measured in 2,442 participants without CVD in the Dallas Heart Study, a probability-based population sample aged 30-65 years enrolled between 2000 and 2002. ASCVD was defined as first myocardial infarction, stroke, coronary revascularization, or CV death. A total of 162 ASCVD events were analyzed over 10.4 years.

RESULTS

Increasing sESAM was associated with ASCVD, independent of risk factors (HR Q4 vs Q1: 2.7, 95% CI 1.6-4.6). Serial adjustment for renal function, sICAM-1, VCAM-1, and prevalent coronary calcium did not attenuate these associations. Continuous ESAM demonstrated similar findings (HR 1.31, 95% CI 1.2-1.4). Addition of sESAM to traditional risk factors improved discrimination and reclassification (delta c-index: P = .009; integrated-discrimination-improvement index P = .001; net reclassification index = 0.42, 95% CI 0.15-0.68). Neither sICAM-1 nor sVCAM-1 was independently associated with ASCVD.

CONCLUSIONS

sESAM but not sICAM-1 or sVCAM-1 levels are associated with incident ASCVD. Further studies are warranted to investigate the role of sESAM in ASCVD.

Beyond Coronary Calcification, Family History, and C-Reactive Protein: Cholesterol Efflux Capacity and Cardiovascular Risk Prediction

BACKGROUND

Cholesterol efflux capacity (CEC), which is a key step in the reverse cholesterol transport pathway, is independently associated with atherosclerotic cardiovascular disease (ASCVD). However, whether it predicts ASCVD beyond validated novel risk markers is unknown.

OBJECTIVES

This study assessed if CEC improved ACSVD risk prediction beyond using coronary artery calcium (CAC), family history (FH), and high-sensitivity C-reactive protein (hs-CRP).

METHODS

CEC, CAC, self-reported FH, and hs-CRP were assessed among participants without baseline ASCVD who were enrolled in the Dallas Heart Study (DHS). ASCVD was defined as a first nonfatal myocardial infarction (MI) or stroke, coronary revascularization, or cardiovascular death, assessed over a median 9.4 years. Risk prediction was assessed using various modeling techniques and improvements in the c-statistic, the integrated discrimination index (IDI), and the net reclassification index (NRI).

RESULTS

The mean age of the population (N = 1,972) was 45 years, 52% had CAC (>0), 31% had FH, and 58% had elevated hs-CRP (≥2 mg/l). CEC greater than the median was associated with a 50% reduced incidence of ASCVD in those with CAC (5.4% vs. 10.5%; p = 0.003), FH (5.8% vs. 10%; p = 0.05), and elevated hs-CRP (3.8% vs. 7.9%; p = 0.004). CEC improved all metrics of discrimination and reclassification when added to CAC (c-statistic, p = 0.004; IDI, p = 0.02; NRI: 0.38; 95% confidence interval [CI]: 0.13 to 0.53), FH (c-statistic, p = 0.006; IDI, p = 0.008; NRI: 0.38; 95% CI: 0.13 to 0.55), or elevated hs-CRP (c-statistic p = 0.008; IDI p = 0.02; NRI: 0.36; 95% CI 0.12 to 0.52).

CONCLUSIONS

CEC improves ASCVD risk prediction beyond using CAC, FH, and hs-CRP and warrants consideration as a novel ASCVD risk marker.

Association of the serum myeloperoxidase/high-density lipoprotein particle ratio and incident cardiovascular events in a multi-ethnic population: Observations from the Dallas Heart Study

BACKGROUND AND AIMS

Myeloperoxidase (MPO), a product of systemic inflammation, promotes oxidation of lipoproteins; whereas, high-density lipoprotein (HDL) exerts anti-oxidative effects in part via paraoxonase-1 (PON1). MPO induces dysfunctional HDL particles; however, the interaction of circulating levels of these measures in cardiovascular disease (CVD) has not been studied in humans. We tested whether serum levels of MPO indexed to HDL particle concentration (MPO/HDLp) are associated with increased CVD risk in a large multiethnic population sample, free of CVD at baseline.

METHODS

Levels of MPO, HDL-C, and HDL particle concentration (HDLp) by NMR were measured at baseline in 2924 adults free of CVD. The associations of MPO/HDLp with incident ASCVD (first non-fatal myocardial infarction, non-fatal stroke, coronary revascularization, or CVD death) and total CVD were assessed in Cox proportional-hazards models adjusted for traditional risk factors. The median follow-up period was 9.4 years.

RESULTS

Adjusted for sex and race/ethnicity, MPO/HDLp was associated directly with body mass index, smoking status, high-sensitivity C-reactive protein, and interleukin 18, and inversely with age, HDL-C levels, HDL size, and PON1 arylesterase activity, but not with cholesterol efflux. In fully adjusted models, the highest versus lowest quartile of MPO/HDLp was associated with a 74% increase in incident ASCVD (aHR, 1.74, 95% CI 1.12-2.70) and a 91% increase in total incident CVD (aHR, 1.91, 95% CI 1.27-2.85).

CONCLUSIONS

Increased MPO indexed to HDL particle concentration (MPO/HDLp) at baseline is associated with increased risk of incident CVD events in a population initially free of CVD over the 9.4 year period.

PCSK9 inhibitor access barriers-issues and recommendations: Improving the access process for patients, clinicians and payers

The proprotein convertase subtilisin/kexin type 9 inhibitors or monoclonal antibodies likely represent the greatest advance in lipid management in 30 years. In 2015 the US Food and Drug Administration approved both alirocumab and evolocumab for high-risk patients with familial hypercholesterolemia (FH) and clinical atherosclerotic cardiovascular disease requiring additional lowering of low-density lipoprotein cholesterol. Though many lipid specialists, cardiovascular disease prevention experts, endocrinologists, and others prescribed the drugs on label, they found their directives denied 80% to 90% of the time. The high frequency of denials prompted the American Society for Preventive Cardiology (ASPC), to gather multiple stakeholder organizations including the American College of Cardiology, National Lipid Association, American Association of Clinical Endocrinologists (AACE), and FH Foundation for 2 town hall meetings to identify access issues and implement viable solutions. This article reviews findings recognized and solutions suggested by experts during these discussions. The article is a product of the ASPC, along with each author writing as an individual and endorsed by the AACE.

The association between gallstone disease and plaque in the abdominopelvic arteries

Background:

The aim of this study was to assess the atheromatous plaque, in the abdominopelvic arteries as a marker of cardiac risk in patients with or without gallstone disease (GD).

Materials and Methods:

A total of 136 patients were enrolled in this cross-sectional study. Forty-eight patients had GD and the remaining 88 patients did not. The presence or absence of gallstones was noted during abdominal ultrasonography while vascular risk factors such as plaque formation, intima-media thickness, plaque calcification, mural thrombus, stenosis, aneurysm, and inflammation were recorded during an abdominopelvic computed tomography scan. In addition, percentage of the abdominopelvic aorta surface covered by atheromatous plaque was calculated.

Results:

The mean age of patients with GD and without GD was 50.81 ± 16.20 and 50.40 ± 12.43, respectively. Patients with GD were more likely to have diabetes mellitus, a higher body mass index (BMI) (P < 0.001), and higher cholesterol (P < 0.01), and low-density lipoprotein-cholesterol (P < 0.02) levels. No significant differences were found between the groups regarding other atherosclerotic risk factors. Patients with GD had significantly higher rates of the vascular risk factors as intima-media thickness, plaque formation, calcification, aneurysm, mural thrombosis, stenosis, and inflammation in all abdominal arterial segments other than aneurysm in the femoral arteries. In addition, patients with GD had severe atheromatous plaques in the abdominal aorta, common iliac, external iliac, and common femoral artery (CFA). In patients with GD, parameters of age, BMI, and systolic and diastolic blood pressure were all correlated with the severity of the atheromatous plaque in abdominal aorta, common iliac, external iliac, and CFA.

Conclusion:

We demonstrated a direct relationship between GD and abdominopelvic atheromatous plaque, which is a marker for increased cardiovascular risk, for the first time in the literature. Patients with GD exhibit greater abdominopelvic atherosclerosis and therefore, have a higher risk of cardiovascular disease.

Influence of race/ethnicity on cardiovascular risk factors in polycystic ovary syndrome, the Dallas Heart Study

OBJECTIVE

Polycystic ovarian syndrome (PCOS) is estimated to affect up to 20% of women. PCOS is associated with insulin resistance and cardiovascular (CV) risk factors. We aimed to evaluate the impact of race/ethnicity on the prevalence of CV risk factors and subclinical predictors of CV events.

DESIGN

Cross-sectional analysis of data collected by the Dallas Heart Study, an urban, population-based cohort oversampled for blacks.

PATIENTS

A previously described cohort of women with PCOS and control subjects of the same racial/ethnic group, matched for age and body mass index.

MEASUREMENTS

Hormonal and clinical measures associated with PCOS and CV risk factors.

RESULTS

The study included 117 women with PCOS and 204 controls. Women with PCOS had significant differences across racial/ethnic groups in the prevalence of hypertension, hypercholesterolaemia, hypertriglyceridaemia and impaired fasting glucose (P < 0·05). Controls showed significant racial/ethnic differences in the prevalence of hypertension and impaired fasting glucose (P < 0·05). The odds of hypertension were significantly greater among women with PCOS than controls after adjusting for race/ethnicity (odds ratio, 1·50 [95% CI, 1·03-2·30]; P = 0·04). However, we did not see an interaction of race/ethnicity that significantly changed CV risk factor prevalence between PCOS and controls. In addition, subclinical measures of CV disease were not different between women with PCOS vs controls, even among hypertensive women.

CONCLUSIONS

Race/ethnicity affects the prevalence of CV risk factors for women with and without PCOS. However, race/ethnicity does not interact with PCOS to additionally increase CV risk factor prevalence or subclinical CV disease.

Target Organ Complications and Cardiovascular Events Associated With Masked Hypertension and White-Coat Hypertension: Analysis From the Dallas Heart Study

BACKGROUND

Multiple epidemiological studies from Europe and Asia have demonstrated increased cardiovascular risks associated with isolated elevation of home blood pressure (BP) or masked hypertension (MH). Previous studies have not addressed cardiovascular outcomes associated with MH and white-coat hypertension (WCH) in the general population in the United States.

OBJECTIVES

The goal of this study was to determine hypertensive target organ damage and adverse cardiovascular outcomes associated with WCH (high clinic BP, ≥140/90 mm Hg; normal home BP, <135/85 mm Hg), MH (high home BP, ≥135/85 mm Hg; normal clinic BP, <140/90 mm Hg), and sustained hypertension (high home and clinic BP) in the DHS (Dallas Heart Study), a large, multiethnic, probability-based population cohort.

METHODS

Associations among WCH, MH, sustained hypertension, and aortic pulsed wave velocity by magnetic resonance imaging; urinary albumin-to-creatinine ratio; and cystatin C were evaluated at study baseline. Then, associations between WCH and MH with incident cardiovascular outcomes (coronary heart disease, stroke, atrial fibrillation, heart failure, and cardiovascular death) over a median follow-up period of 9 years were assessed.

RESULTS

The study cohort comprised 3,027 subjects (50% African Americans). The sample-weighted prevalence rates of WCH and MH were 3.3% and 17.8%, respectively. Both WCH and MH were independently associated with increased aortic pulsed wave velocity, cystatin C, and urinary albumin-to-creatinine ratio. Both WCH (adjusted hazard ratio: 2.09; 95% confidence interval: 1.05 to 4.15) and MH (adjusted hazard ratio: 2.03; 95% confidence interval: 1.36 to 3.03) were independently associated with higher cardiovascular events compared with the normotensive group, even after adjustment for traditional cardiovascular risk factors.

CONCLUSIONS

In a multiethnic U.S. population, both WCH and MH were independently associated with increased aortic stiffness, renal injury, and incident cardiovascular events. Because MH is common and associated with an adverse cardiovascular profile, home BP monitoring should be routinely performed among U.S. adults.

Subclinical atherosclerosis and subsequent cognitive function

OBJECTIVE

To examine the relationship between measures of subclinical atherosclerosis and subsequent cognitive function.

METHOD

Participants from the Dallas Heart Study (DHS), a population-based multiethnic study of cardiovascular disease pathogenesis, were re-examined 8 years later (DHS-2) with the Montreal Cognitive Assessment (MoCA); N = 1904, mean age = 42.9, range 8-65. Associations of baseline measures of subclinical atherosclerosis (coronary artery calcium, abdominal aortic plaque, and abdominal aortic wall thickness) with MoCA scores measured at follow-up were examined in the group as a whole and in relation to age and ApoE4 status.

RESULTS

A significant linear trend of successively lower MoCA scores with increasing numbers of atherosclerotic indicators was observed (F(3, 1150) = 5.918, p = .001). CAC was weakly correlated with MoCA scores (p = .047) and MoCA scores were significantly different between participants with and without CAC (M = 22.35 vs 23.69, p = 0.038). With the exception of a small association between abdominal AWT and MoCA in subjects over age 50, abdominal AWT and abdominal aortic plaque did not correlate with MoCA total score (p ≥ .052). Cognitive scores and atherosclerosis measures were not impacted by ApoE4 status (p ≥ .455).

CONCLUSION

In this ethnically diverse population-based sample, subclinical atherosclerosis was minimally associated with later cognitive function in middle-aged adults.

Relation of black race between high density lipoprotein cholesterol content, high density lipoprotein particles and coronary events (from the Dallas Heart Study)

Therapies targeting high density lipoprotein cholesterol content (HDL-C) have not improved coronary heart disease (CHD) outcomes. HDL particle concentration (HDL-P) may better predict CHD. However, the impact of race/ethnicity on the relations between HDL-P and subclinical atherosclerosis/ incident CHD events has not been described. Participants from the Dallas Heart Study, a multiethnic, probability-based, population cohort of Dallas County adults had the following baseline measurements: HDL-C, HDL-P by nuclear magnetic resonance imaging (NMR), and coronary artery calcium (CAC) by electron beam computed tomography. Participants were followed for a median of 9.3 years for incident CHD events (composite of first myocardial infarction, stroke, coronary revascularization, or cardiovascular death). The study comprised 1977 participants free from CHD (51% women, 46% Black). In adjusted models, HDL-C was not associated with prevalent CAC (p=0.13) or incident CHD overall (HR per 1SD: 0.89, 95% CI 0.76–1.05). However, HDL-C was inversely associated with incident CHD among non-Black (adjusted HR per 1SD 0.67, 95% CI 0.46–0.97) but not Black participants (HR 0.94, 95% CI 0.78–1.13, p_interaction = 0.05). Conversely, HDL-P, adjusted for risk factors and HDL-C, was inversely associated with prevalent CAC (p=0.009) and with incident CHD overall (adjusted HR per 1SD: 0.73, 95% CI 0.62–0.86) with no interaction by Black race/ethnicity (p_interaction = 0.57). In conclusion, in contrast to HDL-C, the inverse relationship between HDL-P and incident CHD events is consistent across ethnicities. These findings suggest that HDL-P is superior to HDL-C in predicting both prevalent atherosclerosis as well as incident CHD events across a diverse population and should be considered as a therapeutic target.

Association between number of live births and markers of subclinical atherosclerosis: The Dallas Heart Study

AIMS

Higher parity has been associated with increased maternal risk of cardiovascular disease, but the mechanism is not well delineated. Whether the number of live births is associated with coronary and aortic subclinical atherosclerosis has not been fully evaluated.

METHODS AND RESULTS

Women from the Dallas Heart Study, a multiethnic population-based cohort of subjects aged 30-65 years, were included if they had data on self-reported live births and coronary artery calcium (CAC) measured by computed tomography or aortic wall thickness (AWT) by MRI. Coronary artery calcium was positive if >10 Agatston units, and aortic wall thickness if greater than the 75(th) percentile reference point for age and gender. Among the 1644 women included in the study, the mean age was 45 years and 55% were Black. Sequential multivariable models were done adjusting for age, race, traditional cardiovascular risk factors, body mass index, income, education, hormone replacement therapy, oral contraceptives, and physical activity. Using women with 2-3 live births as the reference, those with four or more live births had an increased prevalence of elevated coronary artery calcium (odds ratio (OR) 2.2, 95% confidence interval (CI) 1.28-3.65) and aortic wall thickness (OR 1.6, 95% CI 1.04-2.41). Women with 0-1 live births also had increased coronary artery calcium (OR 1.9, 95% CI 1.16-3.03) and aortic wall thickness (OR 1.5, 95% CI 1.05-2.09) after multivariable adjustment.

CONCLUSION

The number of live births is associated with subclinical coronary and aortic atherosclerosis, with an apparent U-shaped relationship. Further studies are needed to confirm this association and explore the biological underpinnings of these findings.

Site-specific association between distal aortic pulse wave velocity and peripheral arterial stenosis severity: a prospective cardiovascular magnetic resonance study

BACKGROUND

Vascular disease expression in one location may not be representative for disease severity in other vascular territories, however, strong correlation between disease expression and severity within the same vascular segment may be expected. Therefore, we hypothesized that aortic stiffening is more strongly associated with disease expression in a vascular territory directly linked to that aortic segment rather than in a more remote segment. We prospectively compared the association between aortic wall stiffness, expressed by pulse wave velocity (PWV), sampled in the distal aorta, with the severity of peripheral arterial occlusive disease (PAOD) as compared to atherosclerotic markers sampled in remote vascular territories such as PWV in the proximal aorta and the normalized wall index (NWI), representing the vessel wall thickness, of the left common carotid artery.

METHODS

Forty-two patients (23 men; mean age 64±10 years) underwent velocity-encoded cardiovascular magnetic resonance (CMR) in the proximal and distal aorta, whole-body contrast-enhanced MR angiography (CE-MRA) and carotid vessel wall imaging with black-blood CMR in the work-up for PAOD. Strength of associations between aortic stiffness, carotid NWI and peripheral vascular stenosis grade were assessed and evaluated with multiple linear regression.

RESULTS

Stenosis severity correlated well with PWV in the distal aorta (Pearson rP=0.64, p<0.001, Spearman rS=0.65, p<0.001) but to a lesser extent with PWV in the proximal aorta (rP=0.48, p=0.002, rS=0.22, p=0.18). Carotid NWI was not associated with peripheral stenosis severity (rP=0.17, p=0.28, rS=0.14, p=0.37) nor with PWV in the proximal aorta (rP=0.22, p=0.17) nor in the distal aorta (rP=0.21, p=0.18). Correlation between stenosis severity and distal aortic PWV remained statistically significant after correction for age and gender.

CONCLUSIONS

Distal aortic wall stiffness is more directly related to peripheral arterial stenosis severity than markers from more remote vascular territories such as proximal aortic wall stiffness or carotid arterial wall thickness. Site-specific evaluation of vascular disease may be required for full vascular risk estimation.

HDL cholesterol efflux capacity and incident cardiovascular events

BACKGROUND

It is unclear whether high-density lipoprotein (HDL) cholesterol concentration plays a causal role in atherosclerosis. A more important factor may be HDL cholesterol efflux capacity, the ability of HDL to accept cholesterol from macrophages, which is a key step in reverse cholesterol transport. We investigated the epidemiology of cholesterol efflux capacity and its association with incident atherosclerotic cardiovascular disease outcomes in a large, multiethnic population cohort.

METHODS

We measured HDL cholesterol level, HDL particle concentration, and cholesterol efflux capacity at baseline in 2924 adults free from cardiovascular disease who were participants in the Dallas Heart Study, a probability-based population sample. The primary end point was atherosclerotic cardiovascular disease, defined as a first nonfatal myocardial infarction, nonfatal stroke, or coronary revascularization or death from cardiovascular causes. The median follow-up period was 9.4 years.

RESULTS

In contrast to HDL cholesterol level, which was associated with multiple traditional risk factors and metabolic variables, cholesterol efflux capacity had minimal association with these factors. Baseline HDL cholesterol level was not associated with cardiovascular events in an adjusted analysis (hazard ratio, 1.08; 95% confidence interval [CI], 0.59 to 1.99). In a fully adjusted model that included traditional risk factors, HDL cholesterol level, and HDL particle concentration, there was a 67% reduction in cardiovascular risk in the highest quartile of cholesterol efflux capacity versus the lowest quartile (hazard ratio, 0.33; 95% CI, 0.19 to 0.55). Adding cholesterol efflux capacity to traditional risk factors was associated with improvement in discrimination and reclassification indexes.

CONCLUSIONS

Cholesterol efflux capacity, a new biomarker that characterizes a key step in reverse cholesterol transport, was inversely associated with the incidence of cardiovascular events in a population-based cohort. (Funded by the Donald W. Reynolds Foundation and others.).

Cardiovascular outcome associations among cardiovascular magnetic resonance measures of arterial stiffness: the Dallas heart study

BACKGROUND

Cardiovascular magnetic resonance (CMR) has been validated for the noninvasive assessment of total arterial compliance and aortic stiffness, but their associations with cardiovascular outcomes is unknown. The purpose of this study was to evaluate associations of CMR measures of total arterial compliance and two CMR measures of aortic stiffness with respect to future cardiovascular events.

METHODS

The study consisted of 2122 Dallas Heart Study participants without cardiovascular disease who underwent CMR at 1.5 Tesla. Aortic stiffness was measured by CMR-derived ascending aortic distensibility and aortic arch pulse wave velocity. Total arterial compliance was calculated by dividing left ventricular stroke volume by pulse pressure. Participants were monitored for cardiovascular death, non-fatal cardiac events, and non-fatal extra-cardiac vascular events over 7.8 ± 1.5 years. Cox proportional hazards regression was used to assess for associations between CMR measures and cardiovascular events.

RESULTS

Age, systolic blood pressure, and resting heart rate were independently associated with changes in ascending aortic distensibility, arch pulse wave velocity, and total arterial compliance (all p < .0001). A total of 153 participants (6.9%) experienced a cardiovascular event. After adjusting for traditional risk factors, total arterial compliance was modestly associated with increased risk for composite events (HR 1.07 per 1SD, p = 0.03) while the association between ascending aortic distensibility and composite events trended towards significance (HR 1.18 per 1SD, p = 0.08). Total arterial compliance and aortic distensibility were independently associated with nonfatal cardiac events (HR 1.11 per 1SD, p = 0.001 and HR 1.45 per 1SD, p = 0.0005, respectively), but not with cardiovascular death or nonfatal extra-cardiac vascular events. Arch pulse wave velocity was independently associated with nonfatal extra-cardiac vascular events (HR 1.18 per 1SD, p = 0.04) but not with cardiovascular death or nonfatal cardiac events.

CONCLUSIONS

In a multiethnic population free of cardiovascular disease, CMR measures of arterial stiffness are associated with future cardiovascular events. Total arterial compliance and aortic distensibility may be stronger predictors of nonfatal cardiac events, while pulse wave velocity may be a stronger predictor of nonfatal extra-cardiac vascular events.

MRI-based determination of reference values of thoracic aortic wall thickness in a general population

OBJECTIVES

To provide age- and sex-specific reference values for MRI-derived wall thickness of the ascending and descending aorta in the general population.

MATERIALS AND METHODS

Data of 753 subjects (311 females) aged 21-81 years were analysed. MRI was used to determine the aortic wall thickness (AWT). Equations for reference value calculation according to age were established for females and males.

RESULTS

Median wall thickness of the ascending aorta was 1.46 mm (5th-95th range: 1.15-1.88 mm) for females and 1.56 mm (1.22-1.99 mm) for males. Median wall thickness of the descending aorta was 1.26 mm (0.97-1.58 mm) in females and 1.36 mm (1.04-1.75 mm) in males. While median and 5th and 95th percentiles for the ascending and descending aorta increased with age in both sexes, the association between age and median AWT was stronger in males than in females for both the ascending and descending aorta.

CONCLUSIONS

Reference values for the ascending and descending AWT are provided. In a healthy sample from the general population, the wall of the ascending aorta is thicker than the wall of the descending aorta, and both walls are thicker in males than females. The increase in wall thickness with age is greater in males.

KEY POINTS

Ascending aortic wall thickness is greater than descending aortic wall thickness. Ascending and descending aortic wall thickness is greater in males. Thoracic aortic wall thickness increases with age in both sexes. The age-related increase in aortic wall thickness is stronger in males.