Coronary artery calcium evaluation by electron beam computed tomography and its relation to new cardiovascular events

Triglyceride-glucose index is an independent predictor of coronary artery calcification progression in patients with chronic kidney disease

BACKGROUND

Coronary artery calcification (CAC) is highly prevalent in patients with chronic kidney disease (CKD) and is associated with major adverse cardiovascular events and metabolic disturbances. The triglyceride-glucose index (TyGI), a novel surrogate marker of metabolic syndrome and insulin resistance, is associated with CAC in the general population and in patients with diabetes. This study investigated the association between the TyGI and CAC progression in patients with CKD, which is unknown.

METHODS

A total of 1,154 patients with CKD (grades 1-5; age, 52.8 ± 11.9 years; male, 688 [59.6%]) were enrolled from the KNOWCKD (KoreaN Cohort Study for Outcomes in Patients With Chronic Kidney Disease). The TyGI was calculated as follows: ln (fasting triglycerides × fasting glucose/2). Patients were classified into tertiles (low, intermediate, high) based on the TyGI. The primary outcome was annualized percentage change in CAC score [(percent change in CAC score + 1)12/follow-up months - 1] of ≥15%, defined as CAC progression.

RESULTS

During the 4-year follow-up, the percentage of patients with CAC progression increased across TyGI groups (28.6%, 37.5%, and 46.2% in low, intermediate, and high groups, respectively; p < 0.001). A high TyGI was associated with an increased risk of CAC progression (odds ratio [OR], 2.11; 95% confidence interval [CI], 1.14-3.88; p = 0.02) compared to the low group. Moreover, a 1-point increase in the TyGI was related to increased risk of CAC progression (OR, 1.55; 95% CI, 1.06-1.76; p = 0.02) after adjustment.

CONCLUSION

A high TyGI may be a useful predictor of CAC progression in CKD.

The Clear Value of Coronary Artery Calcification Evaluation on Non-Gated Chest Computed Tomography for Cardiac Risk Stratification

To enhance risk stratification in patients suspected of coronary artery disease, the assessment of coronary artery calcium (CAC) could be incorporated, especially when CAC can be readily assessed on previously performed non-gated chest computed tomography (CT). Guidelines recommend reporting on patients' extent of CAC on these non-cardiac directed exams and various studies have shown the diagnostic and prognostic value. However, this method is still little applied, and no current consensus exists in clinical practice. This review aims to point out the clinical utility of different kinds of CAC assessment on non-gated CTs. It demonstrates that these scans indeed represent a merely untapped and underestimated resource for risk stratification in patients with stable chest pain or an increased risk of cardiovascular events. To our knowledge, this is the first review to describe the clinical utility of different kinds of visual CAC evaluation on non-gated unenhanced chest CT. Various methods of CAC assessment on non-gated CT are discussed and compared in terms of diagnostic and prognostic value. Furthermore, the application of these non-gated CT scans in the general practice of cardiology is discussed. The clinical utility of coronary calcium assessed on non-gated chest CT, according to the current literature, is evident. This resource of information for cardiac risk stratification needs no specific requirements for scan protocol, and is radiation-free and cost-free. However, some gaps in research remain. In conclusion, the integration of CAC on non-gated chest CT in general cardiology should be promoted and research on this method should be encouraged.

Evaluation of perivascular fat attenuation with coronary CT angiography in cardiac transplantation patients: an imaging biomarker candidate for prediction of cardiac mortality and re-transplantation

OBJECTIVES

In cardiac transplant recipients, non-invasive allograft surveillance for identifying patients at risk for graft failure remains challenging. The fat attenuation index (FAI) of the perivascular adipose tissue in coronary computed tomography angiography (CCTA) predicts outcomes in coronary artery disease in non-transplanted hearts; however, it has not been evaluated in cardiac transplant patients.

METHODS

We followed 39 cardiac transplant patients with two or more CCTAs obtained between 2010 and 2021. We performed FAI measurements around the proximal 4 cm segments of the left anterior descending (LAD), right coronary artery (RCA), and left circumflex artery (LCx) using a previously validated methodology. The FAI was analyzed at a threshold of - 30 to - 190 Hounsfield units.

RESULTS

FAI measurements were completed in 113 CCTAs, obtained on two same-vendor CT models. Within each CCTA, the FAI values between coronary vessels were strongly correlated (RCA and LAD R = 0.67 (p < 0.0001), RCA and LCx R = 0.58 (p < 0.0001), LAD and LCx R = 0.67 (p < 0.0001)). The FAIs of each coronary vessel between the patient's first and last CCTA completed at 120 kV were also correlated (RCA R = 0.73 (p < 0.0001), LAD R = 0.81 (p < 0.0001), LCx R = 0.55 (p = 0.0069). Finally, a high mean FAI value of all three coronary vessels at baseline (mean ≥  - 71 HU) was predictive of cardiac mortality or re-transplantation, however, not predictive of all cause-mortality.

CONCLUSION

High baseline FAI values may identify a higher-risk cardiac transplant population; thus, FAI may support the implementation of CCTA in post-transplant surveillance.

KEY POINT

• Perivascular fat attenuation measured with coronary CT is feasible in cardiac transplant patients and may predict cardiac mortality or need for re-transplantation.

Association of apolipoproteins C-I and C-II truncations with coronary heart disease and progression of coronary artery calcium: Multi-Ethnic Study of Atherosclerosis

BACKGROUND AND AIMS

Higher truncated-to-native proteoform ratios of apolipoproteins (apo) C-I (C-I'/C-I) and C-II (C-II'/C-II) are associated with less atherogenic lipid profiles. We examined prospective relationships of C-I'/C-II and C-II'/C-II with coronary heart disease (CHD) and coronary artery calcium (CAC).

METHODS

ApoC-I and apoC-II proteoforms were measured by mass spectrometry immunoassay in 5790 MESA baseline plasma samples. CHD events (myocardial infarction, resuscitated cardiac arrest, fatal CHD, n = 434) were evaluated for up to 17 years. CAC was measured 1-4 times over 10 years for incident CAC (if baseline CAC = 0), and changes (follow-up adjusted for baseline) in CAC score and density (if baseline CAC>0).

RESULTS

C-II'/C-II was inversely associated with CHD (n = 434 events) after adjusting for non-lipid cardiovascular risk factors (Hazard ratio: 0.89 [95% CI: 0.81-0.98] per SD), however, the association was attenuated after further adjustment for HDL levels (0.93 [0.83-1.03]). There was no association between C-I'/C-I and CHD (0.98 [0.88-1.08]). C-II'/C-II was positively associated with changes in CAC score (3.4% [95%CI: 0.6, 6.3]) and density (6.3% [0.3, 4.2]), while C-I'/C-I was inversely associated with incident CAC (Risk ratio: 0.89 [95% CI: 0.81, 0.98]) in fully adjusted models that included plasma lipids. Total apoC-I and apoC-II concentrations were not associated with CHD, incident CAC or change in CAC score.

CONCLUSIONS

Increased apoC-II truncation was associated with reduced CHD, possibly explained by differences in lipid metabolism. Increased apoC-I and apoC-II truncations were also associated with less CAC progression and/or development of denser coronary plaques.

Coronary calcium density in relation to coronary heart disease and cardiovascular disease in adults with diabetes or metabolic syndrome: the Multi-ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Coronary artery calcium (CAC) density is inversely associated with coronary heart disease (CHD) and cardiovascular disease (CVD) risk. We examined this relation in those with diabetes mellitus (DM) or metabolic syndrome (MetS).

METHODS

We studied 3,818 participants with non-zero CAC scores from the Multiethnic Study of Atherosclerosis and classified them as DM, MetS (without DM) or neither DM/MetS. Risk factor-adjusted CAC density was calculated and examined in relation to incident CHD and CVD events over a median follow-up of 15 years among these three disease groups.

RESULTS

Adjusted CAC density was 2.54, 2.61 and 2.69 among those with DM, MetS or neither DM/MetS. Hazard ratios (HRs) for CHD per 1 SD increase of CAC density was 0.91 (95% CI: 0.72-1.16), 0.70 (95% CI: 0.56-0.87) and 0.79 (95% CI: 0.66-0.95) for those with DM, MetS or neither DM/MetS groups and were 0.77 (95% CI: 0.64-0.94), 0.83 (95% CI: 0.70-0.99) and 0.82 (95% CI: 0.71-0.95) for CVD, respectively. Adjustment for CAC density increased the HRs of CAC volume for CHD/CVD events. Compared to prediction models with or without single CAC measures, c-statistics of models with CAC volume and density were the highest ranging 0.67-0.72.

CONCLUSION

CAC density is lower among patients with DM or MetS than those with neither DM/MetS and is inversely associated with future CHD/CVD risk among them. Including CAC density in risk assessment among those with MetS may improve prediction of CHD and CVD.

Evolution of Coronary Calcium Screening for Assessment of Atherosclerotic Cardiovascular Disease Risk and Role in Preventive Cardiology

PURPOSE OF REVIEW

Coronary artery calcium (CAC) is an important measure of subclinical atherosclerosis and strongly predicts atherosclerotic cardiovascular disease (ASCVD) outcomes. The purpose of this review is to discuss the key studies that have helped to establish its role as an important screening tool and its place in preventive cardiology.

RECENT FINDINGS

Epidemiologic studies document a strong relation of age, race/ethnicity, and risk factors with the prevalence and extent of CAC. Large-scale registry and prospective investigations show CAC to be the strongest subclinical disease predictor of ASCVD outcomes, with higher CAC scores associated with successively higher risks and those with a CAC score of 0 having a long-term "warranty" against having events. Moreover, CAC is associated with greater initiation of preventive health behaviors and therapy. Current US guidelines utilize CAC to inform the treatment decision for statin therapy. Further study is underway to document whether CAC screening will ultimately improve clinical outcomes. CAC is well established as the most important subclinical cardiovascular disease measure for prediction of future ASCVD outcomes and can be used for informing the treatment decision for preventive therapies.

De-risking primary prevention: role of imaging

Atherosclerotic cardiovascular disease (ASCVD) is a common disease among the general population, and includes four major areas: (1) coronary heart disease (CHD), manifested by stable angina, unstable angina, myocardial infarction (MI), heart failure, and coronary death; (2) cerebrovascular disease, manifested by transient ischemia attack and stroke; (3) peripheral vascular disease, manifested by claudication and critical limb ischemia; and (4) aortic atherosclerosis and aortic aneurysm (thoracic and abdominal). CHD remains the leading cause of death for both men and women in the United States. So, it is imperative to identify people at risk of CHD and provide appropriate medical treatment or intervention to prevent serious complications and outcomes including sudden cardiac death. Coronary artery calcification (CAC) is a marker of subclinical coronary artery disease. Therefore, coronary artery calcium score is an important screening method for Coronary artery disease (CAD). In this article, we performed a comprehensive review of current literatures and studies assessing the prognostic value of CAC for future cardiovascular disease (CVD) events. We searched PubMed, MEDLINE, Google Scholar, and Cochrane library. We also reviewed the 2018 American College of Cardiology (ACC)/American Heart Association (AHA) guideline on the assessment of CVD risk. A CAC score of zero corresponds to very low CVD event rates (∼1% per year) and hence a potent negative risk marker. This has been referred to as the ‘power of zero’ and affords the lowest risk of any method of risk calculation. It is now indicated in the 2018 ACC/AHA Cholesterol guidelines to be used to avoid statins for 5–10 years after a score of zero, and then re-assess the patient.

The association between triglyceride-glucose index and major adverse cardiovascular events in patients with acute coronary syndrome - dose-response meta-analysis

BACKGROUND AND AIMS

Triglyceride-Glucose (TyG) index is an accurate biomarker of insulin resistance, which is potentially associated with adverse cardiovascular events. We aimed to assess the dose-response relationship between Triglyceride-Glucose (TyG) Index and Major Adverse Cardiovascular Events (MACE) in patients with Acute Coronary Syndrome (ACS).

METHODS AND RESULTS

A systematic literature search was performed using PubMed, Scopus, and Embase for records published from the inception up until 7 February 2021. Studies that fulfilled all of these criteria were included: 1) prospective or retrospective observational studies reporting patients with ACS and 2) assessing the impact of TyG index on MACE with at least three quantitative classifications. The outcome of interest is MACE across the TyG index intervals. MACE was a composite of all-cause mortality, myocardial infarction, unstable angina pectoris, target vessel revascularization, cerebrovascular accidents, and heart failure. The effect estimates were reported as relative risks (RRs). There are 13,684 subjects from 4 studies included in this meta-analysis. This meta-analysis showed that the highest category of TyG index was associated with twofold MACE (RR 2.09 [1.59, 2.76], p < 0.001; I²: 68.4%, p = 0.02) compared to the lowest category in patients with ACS. Dose-response meta-analysis showed that the relationship between TyG index and MACE was non-linear (p < 0.001), with statistical significance reached around TyG index 8.9 and increased non-linearly. The dose-response curve became significantly steeper after TyG index of 9.1-9.2.

CONCLUSION

TyG index was associated with MACE in patients with ACS in a non-linear fashion.

PROSPERO

CRD42021235765.

Machine learning to predict the long-term risk of myocardial infarction and cardiac death based on clinical risk, coronary calcium, and epicardial adipose tissue: a prospective study

AIMS

Our aim was to evaluate the performance of machine learning (ML), integrating clinical parameters with coronary artery calcium (CAC), and automated epicardial adipose tissue (EAT) quantification, for the prediction of long-term risk of myocardial infarction (MI) and cardiac death in asymptomatic subjects.

METHODS AND RESULTS

Our study included 1912 asymptomatic subjects [1117 (58.4%) male, age: 55.8 ± 9.1 years] from the prospective EISNER trial with long-term follow-up after CAC scoring. EAT volume and density were quantified using a fully automated deep learning method. ML extreme gradient boosting was trained using clinical co-variates, plasma lipid panel measurements, risk factors, CAC, aortic calcium, and automated EAT measures, and validated using repeated 10-fold cross validation. During mean follow-up of 14.5 ± 2 years, 76 events of MI and/or cardiac death occurred. ML obtained a significantly higher AUC than atherosclerotic cardiovascular disease (ASCVD) risk and CAC score for predicting events (ML: 0.82; ASCVD: 0.77; CAC: 0.77, P < 0.05 for all). Subjects with a higher ML score (by Youden's index) had high hazard of suffering events (HR: 10.38, P < 0.001); the relationships persisted in multivariable analysis including ASCVD-risk and CAC measures (HR: 2.94, P = 0.005). Age, ASCVD-risk, and CAC were prognostically important for both genders. Systolic blood pressure was more important than cholesterol in women, and the opposite in men.

CONCLUSIONS

In this prospective study, machine learning used to integrate clinical and quantitative imaging-based variables significantly improves prediction of MI and cardiac death compared with standard clinical risk assessment. Following further validation, such a personalized paradigm could potentially be used to improve cardiovascular risk assessment.

Aortic enlargement and coronary artery calcification in a general population cohort

AIMS

The role of atherosclerosis in the pathogenesis of aortic enlargement is uncertain. We aimed to evaluate the relationship between the diameters of the ascending, descending and abdominal aorta, and coronary artery calcification.

METHODS AND RESULTS

Individuals in the Copenhagen General Population Study underwent thoracic and abdominal computed tomography. Maximal aortic diameters were measured in each aortic segment and coronary artery calcium scores (CACS) were calculated. Participants were stratified into five predefined groups according to CACSs and compared to aortic dimensions. The relation between aortic diameter and CACS was adjusted for risk factors for aortic dilatation in a multivariable model. A total of 2678 eligible individuals were included. In all segments of the aorta, aortic diameter was associated to CACSs, with mean increases in aortic diameters ranging from 0.7 to 3.5 mm in individuals with calcified coronary arteries compared to non-calcified subjects (P-value < 0.001). After correction for risk factors, individuals with CACS above 400 had larger ascending, descending and abdominal aortic diameter than the non-calcified reference group (P-value < 0.01).

CONCLUSION

Enlarged thoracic and abdominal aortic vascular segments are associated with co-existing coronary artery calcification in the general population.

Role of coronary artery calcium score in the primary prevention of cardiovascular disease

First developed in 1990, the Agatston coronary artery calcium (CAC) score is an international guideline-endorsed decision aid for further risk assessment and personalized management in the primary prevention of atherosclerotic cardiovascular disease. This review discusses key international studies that have informed this 30 year journey, from an initial coronary plaque screening paradigm to its current role informing personalized shared decision making. Special attention is paid to the prognostic value of a CAC score of zero (the so called "power of zero"), which, in a context of low estimated risk thresholds for the consideration of preventive therapy with statins in current guidelines, may be used to de-risk individuals and thereby inform the safe delay or avoidance of certain preventive therapies. We also evaluate current recommendations for CAC scoring in clinical practice guidelines around the world, and past and prevailing barriers for its use in routine patient care. Finally, we discuss emerging approaches in this field, with a focus on the potential role of CAC informing not only the personalized allocation of statins and aspirin in the general population, but also of other risk-reduction therapies in special populations, such as individuals with diabetes and people with severe hypercholesterolemia.

Prevalence of noncalcified plaques and coronary artery stenosis in patients with coronary calcium scores of zero

OBJECTIVES

A higher coronary artery calcium score (CACS) is associated with increased coronary artery plaque burden resulting in increased cardiovascular risk. Conversely, the absence of calcium indicates a low risk of cardiovascular events. However, coronary plaque calcification is a late manifestation of atherosclerosis; earlier stages of atherosclerosis present noncalcified plaques (NCPs) A recent study demonstrated that the absence of coronary artery calcification deposit does not preclude obstructive stenosis or the need for revascularization in patients with a high suspicion of coronary artery disease (CAD). Our study aimed to investigate the prevalence of NCP and the severity of coronary artery stenosis in symptomatic patients in our local population who were referred for coronary artery computed tomography angiogram (CCTA) with 0 CACS.

METHODS

A total of 299 patients who had undergone CACS and CCTA, and had scored zero for coronary artery calcium. Patients included had clinically appropriate indications, mainly chest pain with variable severity with no history of CAD. The presence of CAD risk factors, such as diabetes, hypertension, and smoking, was obtained from reviewing patient charts. The CCTA analysis was performed to evaluate for coronary artery stenosis and the presence of NCP. The severity of stenosis was quantified by visual estimation and divided into 0% stenosis, 1-25% stenosis, 26-50% stenosis, and more than 50% stenosis.

RESULTS

The prevalence of NCP was 6.4% (19 of the 299). Among the 19 patients with NCP, 52.6% had no identified coronary artery stenosis, 26.3% had less than 25%, and 21% had stenosis between 25 and 50%. None had stenosis greater than 50%. There was a strong association between male sex (P = 0.001), smoking (P = 0.0.004), hypertension, and NCP (P = 0.042), but no association was found between NCP and age or diabetes.

CONCLUSIONS

In patients with a high clinical suspicion of CAD, the absence of coronary artery calcification does not rule out CAD; up to 6.4% of these patients have early CAD as evidenced by NCP detected by CCTA, and none have more than 50% stenosis, However, future prognostic and long-term follow-up studies are needed to determine prognostic value of NCP in patients with 0 CACS.

Cardiovascular risk assessment: The foundation of preventive cardiology

The foundation of preventive cardiology begins with knowing the patient's baseline cardiovascular disease (CVD) risk from which the patient-clinician risk discussion informs on the best ways to lower risk through lifestyle management, as well as a decision about the initiation and intensity of pharmacologic therapy. Global CVD risk assessment involves estimation of cardiovascular risk using a basic panel of risk factors. The Framingham Heart Study championed the first such risk scores, followed by others around the world. Most recently, the Pooled Cohort Equations (PCE) have been recommended in the United States as a starting point in CVD risk assessment. Persons at low (<5%) 10-year risk are generally recommended for lifestyle management only and those at highest (>20%) 10-year risk are recommended for both lifestyle and pharmacologic therapy to reduce risk. Assessing the presence of one or more "risk enhancing" factors is intended to inform the treatment decision in those at borderline (5-<7.5%) or intermediate (7.5-20%) risk, with the use of coronary calcium scores to further refine the treatment decision. Moreover, not all those with ASCVD are treated equal, and recent guidelines provide criteria for identifying those at very high risk. While current techniques best predict long-term risk of CVD events, biomarkers strategies are being developed to predict near-term events, and other imaging techniques such as coronary CT angiography and vascular MRI hold promise to identify vulnerable plaque. Validation and incorporating into clinical practice such state of the art techniques will be vital to moving CVD risk assessment to the next level.

Measures of Adipose Tissue Redistribution and Atherosclerotic Coronary Plaque in HIV

OBJECTIVE

People with HIV (PWH) who are well treated on antiretroviral therapy remain at increased risk for body composition changes, including increased visceral adipose tissue (VAT) and reduced subcutaneous adipose tissue (SAT), as well as increased cardiovascular disease (CVD). The relationship between adipose compartments and coronary disease is not well understood among PWH.

METHODS

A total of 148 PWH and 68 uninfected individuals without CVD were well phenotyped for VAT and SAT via single-section abdominal computed tomography (CT) at L4. Coronary artery calcium (CAC) score was assessed by noncontrast cardiac CT and coronary plaque composition by coronary CT angiography.

RESULTS

Increased VAT was significantly related to increased presence of plaque (OR, 1.55 per 100 cm2 ; P = 0.008) and CAC > 0 (OR, 1.56 per 100 cm2 ; P = 0.006) in the HIV group. In contrast, increased SAT was related to reduced presence of plaque (OR, 0.79 per 100 cm2 ; P = 0.057) and reduced CAC > 0 (OR, 0.69 per 100 cm2 , P = 0.007) among PWH. The VAT to SAT ratio showed a strong relationship to overall presence of calcified plaque (OR, 3.30; P = 0.03) and CAC > 0 (OR, 3.57; P < 0.001) in the HIV group. VAT and waist to hip ratio, but not SAT, were strong predictors of plaque in the uninfected group. BMI did not relate in either group.

CONCLUSIONS

Fat redistribution phenotyping by simultaneous quantification of VAT and SAT as independent measures could help identify those PWH at higher risk for CVD.

Triglyceride glucose index is an independent predictor for the progression of coronary artery calcification in the absence of heavy coronary artery calcification at baseline

BACKGROUND

Data on the relationship between the triglyceride glucose (TyG) index and coronary artery calcification (CAC) progression is limited. This longitudinal study evaluated the association of TyG index with CAC progression in asymptomatic adults.

METHODS

We enrolled 12,326 asymptomatic Korean adults who had at least two CAC evaluations. The TyG index was determined using ln (fasting triglycerides [mg/dL] × fasting glucose [mg/dL]/2). CAC progression was defined as a difference ≥ 2.5 between the square roots (√) of the baseline and follow-up coronary artery calcium score (CACS) (Δ√transformed CACS). Annualized Δ√transformed CACS was defined as Δ√transformed CACS divided by the inter-scan period.

RESULTS

During a mean 3.3 years, the overall incidence of CAC progression was 30.6%. The incidence of CAC progression (group I [lowest]: 22.7% versus [vs.] group II: 31.7% vs. group III [highest]: 37.5%, P < 0.001) and annualized Δ√transformed CACS (group I: 0.46 ± 1.44 vs. group II: 0.71 ± 2.02 vs. group III: 0.87 ± 1.75, P < 0.001) were markedly elevated with increasing TyG index tertiles. Multivariate linear regression analysis showed that TyG index was associated with annualized Δ√transformed CACS (β = 0.066, P = 0.036). In multivariate logistic regression analysis, the TyG index was significantly associated with CAC progression in baseline CACS ≤ 100.

CONCLUSION

The TyG index is an independent predictor of CAC progression, especially in adults without heavy baseline CAC.

Prognostic significance of coronary artery calcium scoring and single-photon emission computed tomographic myocardial perfusion imaging on major adverse cardiac events in patients at low risk for suspected coronary artery disease

Background: To explore the prognostic value of combination of coronary artery calcium scoring (CACS) and single-photon emission computed tomography (SPECT) on the long-term risk of major adverse cardiac events (MACEs) in Chinese patients at low risk of suspected coronary artery disease (CAD).Methods: The medical records of 1876 adult patients who were referred for clinically indicated non-invasive CAD detection with SPECT/CT from January 2011 to December 2013 were retrospectively reviewed. The primary outcome was the occurrence of MACEs, including cardiac death, non-fatal myocardial infarction (MI), unstable angina (UA), and late revascularisation.Results: During a median follow-up of 28.4 ± 9.1 months, 210 patients were identified to have at least one MACEs. Multivariate Cox regression analysis showed that patients with abnormal SPECT had more MACEs compared to those with normal SPECT (HR = 3.41, 95% CI: 2.08-4.71, p < .01). Both moderate (HR = 3.35, 95% CI: 1.76-4.32, p < .01) and severe CACS (HR = 6.56, 95% CI: 4.71-8.23, p < .01) were associated with occurrence of HACEs compared with normal CACS. Moreover, interaction terms for CACS and SPECT findings were reported to be significantly associated with MACE outcomes (p < .01).Conclusions: CACS and SPECT provided both independent and compensatory prognostic information for risk of MACE in patients at low risk of suspected CAD. Our findings strongly support adding a CACS testing in addition to SPECT in asymptomatic patients to better define the risk of cardiac events during follow-up.

The association between left main coronary artery calcium and cardiovascular-specific and total mortality: The Coronary Artery Calcium Consortium

BACKGROUND AND AIMS

Left main (LM) coronary artery disease is associated with greater myocardial infarction-related mortality, however, coronary artery calcium (CAC) scoring does not account for disease location. We explored whether LM CAC predicts excess mortality in asymptomatic adults.

METHODS

Cause-specific cardiovascular and all-cause mortality was studied in 28,147 asymptomatic patients with non-zero CAC scores in the CAC Consortium. Multivariate regression was performed to evaluate if the presence and burden of LM CAC predict mortality after adjustment for clinical risk factors and the Agatston CAC score. We further analyzed the per-unit hazard associated with LM CAC in comparison to CAC in other arteries.

RESULTS

The study population had mean age of 58.3 ± 10 years and CAC score of 301 ± 631. LM CAC was present in 21.7% of the cases. During 312,398 patient-years of follow-up, 1,907 deaths were observed. LM CAC was associated with an increased burden of clinical risk factors and total CAC, and was independently predictive of increased hazard for all-cause (HR 1.2 [1.1, 1.3]) and cardiovascular disease death (HR 1.3 [1.1, 1.5]). The hazard for death increased proportionate to the percentage of CAC localized to the LM. On a per-100 Agatston unit basis, LM CAC was associated with a 6-9% incremental hazard for death beyond knowledge of CAC in other arteries.

CONCLUSIONS

The presence and high burden of left main CAC are independently associated with a 20-30% greater hazard for cardiovascular and total mortality in asymptomatic adults, arguing that LM CAC should be routinely noted in CAC score reports when present.

Multisite atherosclerosis in subjects with metabolic syndrome and diabetes and relation to cardiovascular events: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND AND AIMS

The extent and relation of multisite atherosclerosis to cardiovascular disease (CVD) in metabolic syndrome (MetS) and diabetes (DM) are not well documented. We examined the extent of multisite atherosclerosis and its prognostic value for CVD events in MetS and DM.

METHODS

In CVD-free subjects from the Multi-Ethnic Study of Atherosclerosis, multisite atherosclerosis was measured as: (1) the number of arterial beds involved (coronary calcium>0, abdominal aortic calcium>0, carotid intima-media thickness ≥1 mm and ankle brachial index<1 or ≥1.4); (2) a composite score summing the quartile rank for each atherosclerosis measure. Hazard ratios (HRs) and c-statistics were calculated for incident CVD and coronary heart disease (CHD) over 10.6 years.

RESULTS

Of 1675 individuals (mean age 64 years, 51% male), 33.4% had MetS and 15.9% had DM. The number of atherosclerotic sites was higher in those with DM (mean ± SD = 1.67 ± 1.15) and MetS (1.49 ± 1.12) versus neither MetS/DM (1.09 ± 1.09) (p < 0.0001). CVD rates per 1000 person-years ranged from 3.5, 8.2, and 10.0 in those with 0 sites positive to 35.1, 79.6 and 103.4 in those with 4 sites positive among neither DM/MetS, MetS and DM groups, respectively. HRs (95% CI) for CVD comparing those with 4 vs. 0 atherosclerotic sites were 4.0 (0.8-19.1), 4.9 (2.0-12.0), and 14.4 (3.6-57.6), respectively. C-statistics adding multisite atherosclerosis measures increased over models without the measures and with CIMT or ABI but not CAC.

CONCLUSIONS

Multisite atherosclerosis is greater with MetS or DM, and predicts CVD and CHD events. Risk prediction is improved over CIMT and ABI but not CAC.

Impact of optimal glycemic control on the progression of coronary artery calcification in asymptomatic patients with diabetes

BACKGROUND

Data on the impact of optimal glycemic control (OGC) on the progression of coronary artery calcification, an important marker for future adverse cardiovascular events in individuals with diabetes are limited.

METHODS

We investigated 1637 asymptomatic adults with diabetes (56 ± 8 years, 88.8% men) and no history of coronary artery disease or stroke, who underwent serial coronary artery calcium (CAC) screening. The median inter-scan period was 3.0 (2.0-4.4) years. The change in CAC was compared base on OGC status. OGC was defined as a follow-up hemoglobin A1C (HbA1C) of <7.0%, and CAC progression was defined by a square root (√) transformed difference between the baseline and follow-up CAC scores (Δ √transformed CAC) of ≥2.5.

RESULTS

Despite no significant difference in the baseline CAC scores, the incidence of CAC progression was lower in the OGC group than in the non-OGC group (45.4% vs. 51.7%; p < 0.013). The two groups differed in the Δ √transformed (OGC, 3.8 ± 6.4; non-OGC, 4.7 ± 6.9; p = 0.016) and annualized Δ √transformed CAC (OGC, 1.1 ± 2.4; non-OGC, 1.4 ± 2.6; p = 0.010) scores. Subgroup analysis showed that OGC significantly reduced the risk of CAC progression in patients aged <65 years and in: smokers, and patients with a body mass index of <25 kg/m², dyslipidemia, and baseline CAC scores between 1-100 and >400. In multivariate regression analysis, OGC was independently associated with a reduced risk of CAC progression (odds ratio, 0.745, 95% confidence interval, 0.601-0.924; p = 0.007).

CONCLUSION

OGC attenuated the progression of coronary artery calcification in asymptomatic patients with diabetes.

Cardiac CT: Technological Advances in Hardware, Software, and Machine Learning Applications

Purpose of Review

Multidetector row computed tomography (CT) allows noninvasive imaging of the heart and coronary arteries. The purpose of this review is to briefly summarize recent advances in CT hardware and software technology, and machine learning applications for cardiovascular imaging.

Recent Findings

In the last decades, there have been significant improvements in CT hardware focusing on faster gantry rotation resulting in improved temporal resolution. Concurrent hardware improvements include improved spatial resolution and higher coverage of the patient, enabling faster acquisition. Advances in cardiac CT software include methods for measurement of noninvasive FFR, coronary plaque characterization, and adipose tissue characteristics around the heart. Machine learning approaches using cardiac CT have been shown to improve both risk of prognosis and lesion-specific ischemia.

Summary

Recent advances in CT hardware and software have expanded the clinical utility of CT for cardiovascular imaging. In the next decades, continued advances can be anticipated in these areas, and in machine learning applications in cardiac CT, as they are incorporated into clinical routine for image acquisition, image analysis, and prediction of patient outcomes.

Health and Prevention Enhancement (H-PEACE): a retrospective, population-based cohort study conducted at the Seoul National University Hospital Gangnam Center, Korea

PURPOSE

The Health and Prevention Enhancement (H-PEACE) study was designed to investigate the association of diagnostic imaging results, biomarkers and the predisease stage of non-communicable diseases (NCDs), such as malignancies and metabolic diseases, in an average-risk population in Korea.

PARTICIPANTS

This study enrolled a large-scale retrospective cohort at the Healthcare System Gangnam Center, Seoul National University Hospital, from October 2003 to December 2014.

FINDINGS TO DATE

The baseline and follow-up information collected in the predisease stage of NCDs allows for evaluation of an individual's potential NCD risk, which is necessary for establishing personalised prevention strategies. A total of 91 336 health examinees were included in the cohort, and we repeatedly measured and collected information for 50.9% (n=46 484) of the cohort members. All participants completed structured questionnaires (lifestyle, medical history, mini-dietary assessment index, sex-specific variables and psychiatric assessment), doctors' physical examinations, laboratory blood and urine tests and digital chest X-ray imaging. For participants with available data, we also obtained information on specific diagnostic variables using advanced diagnostic tests, including coronary CT for coronary calcium scores, colonoscopy and brain MRI. Furthermore, 17 455 of the participants who provided informed consent and donated blood samples were enrolled into the Gene-environmental interaction and phenotype study, a subcohort of the H-PEACE, from October 2013, and we analysed genome-wide single-nucleotide polymorphism array data for 6579 of these blood samples.

FUTURE PLANS

The data obtained from this cohort will be used to facilitate advanced and accurate diagnostic techniques related to NCDs while considering various phenotypes. Potential collaborators can access the dataset after receiving approval from our institutional review board. Applications can be submitted on the study homepage (http://en-healthcare.snuh.org/HPEACEstudy).

MicroRNA 8059 as a marker for the presence and extent of coronary artery calcification

Objective

MicroRNAs (miRNAs) may serve as potential biomarkers in a variety of pathologies. The aim of this study was to determine whether miRNAs could serve as blood-based markers of isolated coronary artery calcification (CAC) defined as CAC in the absence of an underlying metabolic abnormality.

Methods

24 age-matched and sex-matched patients who had been referred for elective CT coronary calcium score and angiography as part of investigation for cardiac chest pain were recruited. Peripheral venesection was performed and an Agatston calcium score was derived from the CT coronary angiogram using default software. RNA was extracted using the LeukoLOCK Total RNA Isolation System for Toray's microarray analysis and quantitative reverse transcription PCR (qRT-PCR).

Results

The patients were well matched for age, sex and conventional risk factors for coronary artery disease. Microarray analysis identified lower expression of miRNA-138-2-3p, miRNA-1181, miRNA-6816-3p and miRNA-8059 in patients with coronary artery calcium score (CACS)=0 vs CACS>100. qRT-PCR confirmed significant downregulation of miRNA-8059 in patients with CACS>100 (CACS=0 vs CACS>100; P=0.03).

Conclusion

miRNA-8059 may serve as a peripheral blood-based biomarker for the presence of CAC, as well as provide a platform for studying the pathophysiological basis of isolated CAC.

Trial registration number

NCT01992848; Results.

Cardiac Calcium Evaluation in Hemodialysis Patients with Multisection Spiral Computed Tomography

Aim

The aim of this study is cardiac calcium content evaluation in hemodialysis patients by a new technique, based on ultrafast multisection CT (MTC).

Methods

The study was carried out on 30 HD patients, 14F and 16 M, average age 57.7±13.9 years, average HD age 57.3±47.4 months. The intact PTH levels were 625.4±571 pg/mL. Serum calcium, phosphate and CaxP product were 9.75±0.84 mg/mL, 6.21±1.01 mg/dL and 60.2±10.7 mg2/dL2, respectively.

Results

The values obtained with the MTC technique were reported in terms of Agatson scores. Score values frankly in the pathologic range (>100) were found in 24 patients (80%). Correlation analysis has shown positive and significant correlation coefficients of the score with patients’ age (p=0.003), serum calcium (p=0.012), CaxP (p=0.015), iPTH (=0.049), and borderline, to HD age (p=0.06).

Conclusion

Risk factors for cardiac calcification are mainly age, degree of hyperparathyroidism, increased CaxP and serum calcium levels. A control of calcium phosphate parameters in hemodialysis patients seems to be mandatory to avoid increased severity of coronary artery disease.

Evaluation of the impact of glycemic status on the progression of coronary artery calcification in asymptomatic individuals

BACKGROUND

Data on the influence of glycemic status on the progression of coronary calcification, an important marker for future adverse cardiovascular events, are limited.

METHODS

Data from the Korea Initiatives on Coronary Artery Calcification (KOICA) registry on 12,441 asymptomatic Korean adults (52 ± 9 years, 84.2% males) without previous history of coronary artery disease and stroke, who underwent serial coronary artery calcification (CAC) screening examinations, were included in this study. The median inter-scan period was 3.0 (2.0-4.8) years. All participants were categorized into three groups based on their glycemic status: normal (n = 6578), pre-diabetes (n = 4146), and diabetes (n = 1717). CAC progression was defined as a difference ≥ 2.5 between the square roots (√) of the baseline and follow-up CAC scores.

RESULTS

The incidence of CAC progression was significantly different between the three groups (normal, 26.3%; pre-diabetes, 30.9%; and diabetes, 46.9%; p < 0.001). In the univariate logistic analysis, the risk of CAC progression was higher in the pre-diabetes (odds ratio [OR] 1.253; 95% confidential interval [CI] 1.150-1.366) and diabetes (OR 2.471; 95% CI 2.215-2.758) groups than in the normal group (p < 0.001, both). In the multivariate logistic analysis, the risk of CAC progression was not significantly different between the normal and pre-diabetes groups but was significantly higher in the diabetes group than in the normal group.

CONCLUSIONS

In asymptomatic subjects, diabetes had an incremental impact on CAC progression; however, pre-diabetes did not increase the risk of CAC progression after adjusting for confounding factors.

Prospective comparison of non-invasive risk markers of major cardiovascular events in COPD patients

BACKGROUND

Chronic Obstructive Pulmonary Disease (COPD) is an independent risk factor for cardiovascular (CV) disease, one of the most frequent causes of death in COPD patients. The goal of the present study was to evaluate the prognostic value of non-invasive CV risk markers in COPD patients.

METHODS

CV risk was prospectively evaluated in 287 COPD patients using non-invasive markers including the Framingham score, the Systematic Coronary Risk Evaluation (SCORE) charts, coronary arterial calcium (CAC), epicardial adipose tissue (EAT), as well as clinical, biochemical and physiological variables. The predictive power of each parameter was explored using CV events as the main outcome.

RESULTS

During a median follow up of 65 months (ICR: 36-100), 44 CV events were recorded, 12 acute myocardial infarctions (27.3%), 10 ischemic heart disease/angina (22.7%), 12 peripheral artery disease events requiring surgery (27.3%) and 10 strokes (22.7%). A total of 35 CV deaths occurred during that period. Univariable analysis determined that age, hypertension, CRP, total Cholesterol, LDL-Cholesterol, Framingham score and CAC were independently associated with CV events. Multivariable analysis identified CAC as the best predictor of CV events (HR; 95%CI: 1.32; 1.19-1.46, p < 001).

CONCLUSIONS

In COPD patients attending pulmonary clinics, CAC was the best independent non-invasive predictor of CV events. This tool may help evaluate the risk for a CV event in patients with COPD. Larger studies should reproduce and validate these findings.

The Neutrophil-Lymphocyte Ratio Is Associated with Coronary Artery Calcification in Asymptomatic Korean Males: A Cross-Sectional Study

Introduction. The neutrophil-lymphocyte ratio (NLR) is a significant systemic predictor of cardiovascular disease (CVD). The coronary artery calcium score (CACS) reflects coronary artery calcification and is an independent risk factor for coronary artery stenosis. In the present study, we explored the relationship between the NLR and CACS in terms of subclinical inflammation and coronary artery calcification. Materials and Methods. We evaluated males and females who did not have CVD, diabetes, high blood pressure, or high fasting blood sugar levels. We measured white blood cell, neutrophil, lymphocyte counts, fasting blood sugar, total cholesterol, high-density lipoprotein cholesterol, triglycerides (TG), and high-sensitivity C-reactive protein levels in blood samples. We also obtained CACSs using coronary multidetector computed tomography. Results. Multivariate logistic regression showed that older age was significantly associated with a higher CACS (P < 0.001); males had higher CACSs than females (P < 0.001); and the higher the TG level, the higher the CACS (P = 0.019). The NLR of males, but not females, was significantly associated with the CACS. Conclusion. An independent association between the NLR and CACS was thus evident in healthy adult males after adjusting for other CVD risk factors. Therefore, the NLR is a significant predictor of potential CVD in male subjects with subclinical atherosclerosis.

Review: Cardiovascular risk assessment in the metabolic syndrome, screening for subclinical disease, and implications for treatment

he metabolic syndrome is a clustering of risk factors known to promote or increase the risk for development of cardiovascular disease. Approximately 25—35% of the adult population of developed countries are characterised with metabolic syndrome by different definitions. Metabolic syndrome, even in the absence of diabetes, is associated with an increased risk of cardiovascular disease and total mortality, and is related to an increased risk for the development of diabetes. Initial evaluation of coronary heart disease risk involves global risk estimation using Framingham or other algorithms for risk prediction. Given the absence of key metabolic syndrome risk factors (namely obesity, elevated triglycerides, and impaired fasting glucose) in these algorithms, elevations in these factors need to be considered in individual patient risk evaluation. Further, consideration of screening for novel risk factors such as C-reactive protein, as well as subclinical atherosclerosis (from carotid ultrasound, computed tomography, or ankle-brachial index), can further refine the estimation of future cardiovascular disease risk. The presence of subclinical atherosclerosis or elevated levels of C-reactive protein can potentially modify recommended treatment goals for lipid and other cardiovascular risk factors. The American Heart Association and US National Heart Lung and Blood Institute have recently released revised guidelines for the diagnosis and clinical management of metabolic syndrome. This article examines global assessment of cardiovascular risk in persons with metabolic syndrome, the role of screening for subclinical disease in risk assessment, as well as treatment strategies and their implications for reducing cardiovascular risk in those with metabolic syndrome.

Relationships between measures of adiposity with subclinical atherosclerosis in patients with type 2 diabetes

OBJECTIVE

Assess cross-sectional relationships between body mass index (BMI), waist circumference (WC), pericardial (PAT), visceral (VAT), and subcutaneous adipose tissue (SAT) volumes with calcified plaque (CP) in African Americans (AAs) and European Americans (EAs) with type 2 diabetes.

METHODS

Computed tomography measured PAT, VAT, SAT, and CP in coronary arteries (CAC), carotid arteries, and aorta. Generalized estimating equations models were fitted to test for associations between adiposity and CP, stratified by ethnicity while accounting for familial correlations.

RESULTS

AAs (N = 753) vs. EAs (N = 562) had significantly lower PAT and VAT, despite equal or higher BMI. In multivariable models adjusting for age, gender, education, HbA1c, statins, smoking, cardiovascular disease, hypertension, nephropathy, and C-reactive protein, PAT positively associated with presence of CAC in AAs (P < 0.001), not EAs (P = 0.68; ethnicity interaction P < 0.01). Inverse associations were detected between SAT and severity of aorta CP (P < 0.01) in AAs and between BMI, WC, and SAT with severity of aorta CP in all participants.

CONCLUSIONS

Ethnic- and gender-specific differences in BMI, WC, PAT, SAT, and VAT were present in AAs and EAs with diabetes. Only PAT was positively associated with CAC in AAs; paradoxical inverse associations were seen between several other adiposity measures and subclinical cardiovascular disease.

Prevalence and distribution of coronary calcium in asymptomatic Japanese subjects in lung cancer screening computed tomography

BACKGROUND

Coronary artery calcium (CAC) is associated with a risk of coronary heart disease. The prevalence and distribution of the CAC score have been examined in Western countries, but few studies have been performed in Asia, and especially in Japan. The goal of this study was to investigate CAC scores in an asymptomatic Japanese population.

METHODS

CAC score and risk factors were analyzed in 1834 asymptomatic subjects who underwent lung cancer screening computed tomography.

RESULTS

CAC was present in 26.9% of all the subjects, 29.8% of the males, and 17.1% of the females. In all age groups, the CAC score was higher in males. In multivariate analysis, male gender [odds ratio (OR) 2.461, 95% confidence interval (CI) 1.361-4.452, p=0.002], aging (OR 1.102, 95% CI 1.081-1.123, p<0.001), dyslipidemia (OR 1.740, 95% CI 1.216-2.490, p=0.002), and fasting glucose (OR 1.008, 95% CI 1.002-1.015, p=0.012) were significantly associated with a CAC score >100.

CONCLUSION

The results of this study provide a pattern of CAC distribution based on age and gender in asymptomatic Japanese subjects. This pattern was similar to that in Western countries, although the absolute CAC scores were lower. High CAC scores were associated with male gender, aging, dyslipidemia, and fasting glucose.

Presence and extent of coronary calcified plaque evaluated by coronary computed tomographic angiography are independent predictors of ischemic stroke in patients with suspected coronary artery disease

Although ischemic stroke and coronary artery disease (CAD) share common risk factors and pathophysiology, the risk of stroke in patients with CAD remains unclear. We sought to evaluate the risk of ischemic stroke in patients with suspected CAD according to coronary computed tomographic angiography (CCTA) and single-photon emission computed tomography (SPECT) findings. Presence, severity, and extent of CAD were evaluated in 1137 patients with suspected CAD who underwent CCTA and SPECT. Primary outcome was the occurrence of ischemic stroke. During follow-up (median 26 months), ischemic stroke was observed in 25 patients (2.2%). The presence of coronary plaque on CCTA was associated with the occurrence of ischemic stroke (2.8 vs. 0.6%; p = 0.029), while the presence of PD on SPECT was not (2.0 vs. 2.3%; p = 0.768). Stroke occurrence was not increased by the presence of significant stenosis of ≥50% DS (2.8%; p = 0.943), but was further increased by the plaque presence in ≥2 vessels (6.1 %; p = 0.001) or ≥3 segments (4.1%; p = 0.019). Presence of calcified plaque, and calcified plaque in ≥2 segments were also associated with ischemic stroke occurrence (4.3%; p < 0.001, and 5.6%; p < 0.001, respectively) and were the independent risk factors when adjusted to age of ≥65, hypertension, presence of any coronary plaque and plaque in ≥3 segments (adjusted HR 6.09; 95% CI 1.38-26.87; p = 0.017, and adjusted HR 5.47; 95% CI 1.85-16.19; p = 0.002, respectively). The risk of ischemic stroke was associated with the presence and extent of coronary atherosclerotic plaque evaluated by CCTA, but not with the presence and extent of myocardial ischemia evaluated by SPECT. Especially, calcified coronary plaque presence and extent were the independent predictors of ischemic stroke and allowed further risk stratification.

Mitral Annular and Coronary Artery Calcification Are Associated with Mortality in HIV-Infected Individuals

BACKGROUND

HIV infection increases cardiovascular risk. Coronary artery calcification (CAC) and mitral annular calcification (MAC) identify patients at risk for cardiovascular disease (CVD). The purpose of this study was to examine the association between MAC, CAC and mortality in HIV-infected individuals.

METHODS AND RESULTS

We studied 152 asymptomatic HIV-infected individuals with transthoracic echocardiography (TTE) and computed tomography (CT). MAC was identified on TTE using standardized criteria. Presence of CAC, CAC score and CAC percentiles were determined using the modified Agatston criteria. Mortality data was obtained from the Social Security and National Death Indices (SSDI/NDI). The median age was 49 years; 87% were male. The median duration of HIV was 16 years; 84% took antiretroviral therapy; 64% had an undetectable viral load. CVD risk factors included hypertension (35%), smoking (62%) and dyslipidemia (35%). Twenty-five percent of individuals had MAC, and 42% had CAC. Over a median follow-up of 8 years, 11 subjects died. Subjects with CAC had significantly higher mortality compared to those with MAC only or no MAC. The Harrell's C-statistic of CAC was 0.66 and increased to 0.75 when MAC was added (p = 0.05). MAC, prior CVD, age and HIV viral load were independently associated with higher age- and gender-adjusted CAC percentiles in an adjusted model (p < 0.05 for all).

CONCLUSION

In HIV patients, the presence of MAC, traditional risk factors and HIV viral load were independently associated with CAC. Presence of CAC and MAC may be useful in identifying HIV-infected individuals at higher risk for death.

Coronary calcification in SLE: comparison with the Multi-Ethnic Study of Atherosclerosis

OBJECTIVE

Accelerated atherosclerosis is a major cause of morbidity and death in SLE. The purpose of this study was to determine whether the prevalence and extent of coronary artery calcium (CAC) is higher in female SLE patients compared with a non-SLE sample from the Multi-Ethnic Study of Atherosclerosis (MESA).

METHODS

CAC was measured in 80 female SLE patients and 241 female MESA controls from the Baltimore Field Centre, ages 45-64 years, without evidence of clinical cardiovascular disease. Binary regression was used to estimate the ratio of CAC prevalence in SLE vs MESA controls, controlling for demographic and cardiovascular risk factors. To compare the groups with respect to the quantity of CAC among those with non-zero Agatston scores, we used linear models in which the outcome was a log-transformed Agatston score.

RESULTS

The prevalence of CAC was substantially higher in SLE. The differences were most pronounced and statistically significant in those aged 45-54 years (58% vs 20%, P < 0.0001), but were still observed among those aged 55-65 years (57% vs 36%, P = 0.069). After controlling for age, ethnicity, education, income, diabetes mellitus, hypertension, hyperlipidaemia, high-density lipoprotein levels, smoking, education and BMI, SLE patients still had a significantly higher prevalence of CAC than controls. Among those with CAC, the mean log Agatston score did not differ significantly between SLE and MESA participants.

CONCLUSION

Women with SLE have a higher prevalence of CAC than comparable women without SLE, even after adjusting for traditional cardiovascular risk factors, especially among those aged 45-54 years.

Non-invasive volumetric assessment of aortic atheroma: a core laboratory validation using computed tomography angiography

Aortic atherosclerosis has been linked with worse peri- and post-procedural outcomes following a range of aortic procedures. Yet, there are currently no standardized methods for non-invasive volumetric pan-aortic plaque assessment. We propose a novel means of more accurately assessing plaque volume across whole aortic segments using computed tomography angiography (CTA) imaging. Sixty patients who underwent CTA prior to trans-catheter aortic valve implantation were included in this analysis. Specialized software analysis (3mensio Vascular™, Pie Medical, Maastricht, Netherlands) was used to reconstruct images using a centerline approach, thus creating true cross-sectional aortic images, akin to those images produced with intravascular ultrasonography. Following aortic segmentation (from the aortic valve to the renal artery origin), atheroma areas were measured across multiple contiguous evenly spaced (10 mm) cross-sections. Percent atheroma volume (PAV), total atheroma volume (TAV) and calcium score were calculated. In our populations (age 79.9 ± 8.5 years, male 52 %, diabetes 27 %, CAD 84 %, PVD 20 %), mean ± SD number of cross sections measured for each patient was 35.1 ± 3.5 sections. Mean aortic PAV and TAV were 33.2 ± 2.51 % and 83,509 ± 17,078 mm(3), respectively. Median (IQR) calcium score was 1.5 (0.7-2.5). Mean (SD) inter-observer coefficient of variation and agreement for plaque area among 4 different analysts was 14.1 (5.4), and the mean (95 % CI) Lin's concordance correlation coefficient was 0.79 (0.62-0.89), effectively simulating a Core Laboratory scenario. We provide an initial validation of cross-sectional volumetric aortic atheroma assessment using CTA. This proposed methodology highlights the potential for utilizing non-invasive aortic plaque imaging for risk prediction across a range of clinical scenarios.

Association between metabolic syndrome, smoking status and coronary artery calcification

Coronary artery calcification (CAC), an indicator of coronary artery stenosis, is an independent risk factor of ischemic heart disease. Smoking increases the risk of metabolic syndrome (MS) and cardiovascular disease. Almost no previous studies have evaluated the combined effect of MS and smoking status on CAC. Therefore, in this study we examined the relationships between CAC, MS, and smoking. This study included 775 adult males without histories of cardiovascular disease who visited the Health Promotion Center at the University Hospital in Gyeonggi-do, Republic of Korea from January 2, 2010 to December 31, 2012. All subjects were screened for CAC by multi-detector computed tomography (MDCT). CAC increased significantly with age and body mass index (BMI). Among MS components, abdominal obesity and elevated fasting blood glucose were correlated with CAC. After adjusting for age and BMI, MS was associated with a 1.46-fold increase in CAC (95% CI:1.02-2.09), abdominal obesity was associated with a 1.45-fold increase (95% CI:1.04-2.04), elevated fasting blood glucose was associated with a 2-fold increase (95% CI:1.36-2.94), and MS and smoking combined were associated with 2.44-fold increase in CAC. Thus, the combination of smoking and MS had a greater impact on CAC than any single factor alone. MS is correlated with an increased risk of CAC, and a combination of MS and smoking is associated with even greater risk. These findings can be used to prevent cardiovascular disease in adults.

Does coronary calcium scoring with a SCORE better predict significant coronary artery stenosis than without? Correlation with computed tomography coronary angiography

OBJECTIVE

To determine effectiveness of coronary artery calcium score (CACS) alone and combined with Systematic Coronary Risk Evaluation (SCORE) in adult patients for significant coronary artery stenosis by using computed tomography coronary angiography (CTCA) as reference standard.

METHODS

Two thousand twenty-one patients with suspected coronary artery disease (CAD) underwent CACS test and CTCA. Patients were examined with dual-source CT and were grouped according to their age, gender, CACS, and estimated SCORE risk. Coronary plaque existence and degree of stenosis were assessed with CTCA. Sensitivity, specificity, and ROC curves were analyzed.

RESULTS

CACS was the single independent variable in estimating relative risk of critical stenosis and had superior outcome when compared with SCORE risk in logistic regression and ROC curve. Area under the ROC curve was greatest in the interval between 50-59 years. When SCORE was combined with CACS in patients with zero CACS, percentage of significant stenosis increased from 1.4% to 7.0% in patients with high or very high SCORE risk, and decreased to 0.9 % in patients with low or moderate SCORE risk.

CONCLUSIONS

CACS combination with SCORE risk predicts coronary artery stenosis. When CACS is zero, CTCA can be performed in patients with high or very high SCORE risk.

Coronary artery calcium scanning: the key to the primary prevention of coronary artery disease

Coronary artery calcium scanning (CAC) is the most powerful prognosticator of cardiac risk in the asymptomatic primary prevention population, far exceeding the role of risk factor-based paradigms. The primary utility of risk factors is to identify treatable targets for risk reduction after risk has been determined by CAC. Serial calcium scanning to evaluate progression of calcified plaque is useful for determining the response to treatment. The 2013 cholesterol treatment guidelines understate the value of CAC scanning for atherosclerotic disease risk assessment.

Individual-level concentrations of fine particulate matter chemical components and subclinical atherosclerosis: a cross-sectional analysis based on 2 advanced exposure prediction models in the multi-ethnic study of atherosclerosis

Long-term exposure to outdoor particulate matter with an aerodynamic diameter less than or equal to 2.5 µm (PM2.5) has been associated with cardiovascular morbidity and mortality. The chemical composition of PM2.5 that may be most responsible for producing these associations has not been identified. We assessed cross-sectional associations between long-term concentrations of PM2.5 and 4 of its chemical components (sulfur, silicon, elemental carbon, and organic carbon (OC)) and subclinical atherosclerosis, measured as carotid intima-media thickness (CIMT) and coronary artery calcium, between 2000 and 2002 among 5,488 Multi-Ethnic Study of Atherosclerosis participants residing in 6 US metropolitan areas. Long-term concentrations of PM2.5 components at participants' homes were predicted using both city-specific spatiotemporal models and a national spatial model. The estimated differences in CIMT associated with interquartile-range increases in sulfur, silicon, and OC predictions from the spatiotemporal model were 0.022 mm (95% confidence interval (CI): 0.014, 0.031), 0.006 mm (95% CI: 0.000, 0.012), and 0.026 mm (95% CI: 0.019, 0.034), respectively. Findings were generally similar using the national spatial model predictions but were often sensitive to adjustment for city. We did not find strong evidence of associations with coronary artery calcium. Long-term concentrations of sulfur and OC, and possibly silicon, were associated with CIMT using 2 distinct exposure prediction modeling approaches.

Investigation of relation between visceral and subcutaneous abdominal fat volumes and calcified aortic plaques via multislice computed tomography

OBJECTIVE

The present study investigated effect of subcutaneous fat volume and abdominal visceral fat volume on aortic atherosclerosis via multislice computed tomography.

MATERIALS AND METHODS

The present study comprised 424 subjects who underwent non-contrast-enhanced abdominal CT in our clinic between June 2012 and June 2013. Using dedicated software visceral fat volume was calculated for each individual and then subcutaneous fat volume was calculated by subtracting visceral fat volume from total fat volume. By dividing visceral fat volume/subcutaneous fat volume participants were assigned to three groups according to their mean visceral fat volume/subcutaneous fat volume: Group 1 consisted of subjects with visceral fat volume/subcutaneous fat volume lower than 0.48 (Group 1 < 0.48); Group 2 consisted of subjects with visceral fat volume/subcutaneous fat volume equal to or higher than 0.48 and lower than 0.69 (0.48 ≤ Group 2 < 0.69); and Group 3 consisted of subjects with visceral fat volume/subcutaneous fat volume equal to or higher than 0.69 (Group 3 ≥ 0.69).

RESULTS

The mean abdominal aortic calcium scores according to Agatston scoring (au) were 136.8 ± 418.7 au in Group 1, 179.9 ± 463 au in Group 2 and 212.2 ± 486.9 in Group 3, respectively.

CONCLUSIONS

We have demonstrated a significant correlation between visceral fat volume and abdominal aorta atherosclerosis, while there was absence of significant correlation between subcutaneous fat volume and abdominal atherosclerosis.

Use of ivabradine and atorvastatin in emergent orthopedic lower limb surgery and computed tomography coronary plaque imaging and novel biomarkers of cardiovascular stress and lipid metabolism for the study and prevention of perioperative myocardial infarction: study protocol for a randomized controlled trial

Background

The incidence of perioperative myocardial infarction (PMI) globally is known to be around 2 to 3% and can prolong hospitalization, increased morbidity and mortality. Little is known about the pathophysiology and risk factors for PMI. We investigate the presence of elevated novel cardiac markers and preoperative coronary artery plaque through contemporary laboratory techniques to determine the correlation with PMI, as well as studying ivabradine and atorvastatin as protective pharmacotherapies against PMI in the context of orthopedic surgery.

Methods/Design

We aim to enroll 200 patients aged above 60 years who suffer from neck of femur fracture requiring surgery. Patients will be randomized to four arms (no study drugs, atorvastatin only, ivabradine only and ivabradine and atorvastatin). Our primary outcome is incidence of PMI. All patients will receive an electrocardiogram, cardiac echocardiography, measurement of novel cardiac biomarkers and computed tomography (CT) coronary angiography. A telephone interview post discharge will be conducted at 30 days, 60 days and 1 year.

Discussion

We postulate that ivabradine and atorvastatin will reduce the rate and magnitude of PMI following surgery by reducing heart rate and attenuating catecholamine-induced tachycardia postoperatively. Secondly, we postulate that postoperative reduction in heart rate and catecholamine-induced tachycardia with ivabradine will correlate with a reduction in cardiovascular novel biomarkers which will reduce atrial stretch and postoperative incidence of arrhythmia. We aim to demonstrate that treatment with ivabradine and atorvastatin will cause a reduction in the incidence and magnitude of PMI, the benefit of which is derived primarily in patients with greater atherosclerotic burden as measured by higher CT coronary calcium scores.

Trial registration

This study protocol has been listed in the Australia New Zealand Clinical Trial Registry (registration number: ACTRN12612000340831) on 23 March 2012.

Imaging subclinical atherosclerosis: is it ready for prime time? A review

Imaging subclinical atherosclerosis holds the promise of individualized cardiovascular (CV) risk assessment. The large arsenal of noninvasive imaging techniques available today is playing an increasingly important role in the diagnosis and monitoring of subclinical atherosclerosis. However, there is a debate about the advisability of clinical screens for subclinical atherosclerosis and which modality is the most appropriate for monitoring risk and atherosclerosis progression. This article offers an overview of the traditional and emerging noninvasive imaging modalities used to detect early atherosclerosis, surveys population studies addressing the value of subclinical atherosclerosis detection, and also examines guideline recommendations for their clinical implementation. The clinical relevance of this manuscript lies in the potential of current imaging technology to improve CV risk prediction based on traditional risk factors and the present recommendations for subclinical atherosclerosis assessment. Noninvasive imaging will also help to identify individuals at high CV who would benefit from intensive prevention or therapeutic interventions.

Aortic unfolding determined using non-contrast cardiac computed tomography: correlations with age and coronary artery calcium score

OBJECTIVE

Aortic unfolding occurs with aging and reflects proximal aortic dilation, aortic arch widening, and decreased curvature. This study 1) evaluated the relationship between aortic unfolding measured using non-contrast cardiac-gated computed tomography (CT) and age, 2) assessed factors influencing aortic unfolding, and 3) determined the association of this measurement with coronary artery calcium (CAC) score.

METHODS

We reviewed the charts of 219 subjects (142 men, 77 women; mean age 54.2±9.3 years) who underwent coronary artery calcium scanning during routine health screening from December 2010 to May 2011. Multivariate regression analysis according to cardiovascular risk factors was performed. We also analyzed the relationship between aortic unfolding measurements and CAC score using stepwise multiple linear regression.

RESULTS

Mean aortic unfolding was 103.7±13.9 mm (men, 106.5±13.5 mm; women, 98.4±12.9 mm). Age, body surface area, and hypertension were exclusively associated with aortic unfolding. The association between aortic unfolding and CAC score was significant after adjustment for age and gender (β = 1.89, p = 0.017) and for Framingham risk score (β = 2.83, p<0.001).

CONCLUSIONS

Aortic unfolding defined by measuring aortic width was a reproducible and practical method with non-contrast cardiac CT and associated with age, body surface area, and hypertension. CAC score, a well-established surrogate marker of cardiovascular disease, is positively associated with aortic unfolding. Further study to evaluate aortic unfolding as a potential predictor of cardiovascular risk is warranted.

Association of serum phosphorus variability with coronary artery calcification among hemodialysis patients

Coronary artery calcification (CAC) is associated with increased mortality in patients on maintenance hemodialysis (MHD), but the pathogenesis of this condition is not well understood. We evaluated the relationship of CAC score (CACs) and variability in serum phosphorus in MHD patients. Seventy-seven adults on MHD at Huashan Hospital (Shanghai) were enrolled in July, 2010. CAC of all the patients were measured by computed tomography and CACs was calculated by the Agatston method at the entry of enrollment. Patients were divided into three categories according to their CACs (0∼10, 11∼400, and >400). Blood chemistry was recorded every 3 months from January 2008 to July 2010. Phosphorus variation was defined by the standard deviation (SD) or coefficient of variation (CV) and it was calculated from the past records. The ordinal multivariate logistic regression analysis was used to analyze the predictors of CAC. The mean patient age (± SD) was 61.7 years (±11.3) and 51% of patients were men. The mean CACs was 609.6 (±1062.9), the median CACs was 168.5, and 78% of patients had CACs more than 0. Multivariate analysis indicated that female gender (OR = 0.20, 95% CI = 0.07–0.55), age (OR = 2.31, 95% CI = 1.32–4.04), serum fibroblast growth factor 23 (OR = 2.25, 95% CI = 1.31–3.85), SD-phosphorus calculated from the most recent 6 measurements (OR = 2.12; 95% CI = 1.23–3.63), and CV-phosphorus calculated from the most recent 6 measurements (OR = 1.90, 95% CI = 1.16–3.11) were significantly and independently associated with CACs. These associations persisted for phosphorus variation calculated from past 7, 8, 9, 10, and 11 follow-up values. Variability of serum phosphorus may contribute significantly to CAC and keeping serum phosphorus stable may decrease coronary calcification and associated morbidity and mortality in MHD patients.