Diagnostic and prognostic value of absence of coronary artery calcification

Utility of Coronary Artery Calcium Scores in Predicting Risk of Subclinical Cardiovascular Atherosclerotic Disease: An Analysis of Limitations to its Adoption With Policy Recommendations

This survey-based analysis aims to highlight key limitations to a wider adoption of coronary artery calcium (CAC) scoring as a means of screening asymptomatic individuals for atherosclerotic cardiovascular disease. The need for a screening tool that adds objective anatomical information to historically established risk scores in the aforementioned population has been met by this imaging modality. Despite that, there has been a hesitance towards frequent usage of these scans. Within the pre-set sampling frame of the University of Toledo, a convenience sampling technique was used to reach out to 60 health care providers. The resultant responses were analyzed and discussed. In addition to identifying patients who need to be worked up further, CAC scans can also help re-stratify patients within-risk groups and inform decision-making regarding the use of lipid-lowering therapies. The public health impact of a greater but appropriate utilization of this diagnostic tool will be impactful. This analysis seeks to better understand real-life obstacles to a wider adoption of these scans and attempts to lay out policy recommendations to address these issues.

Cardiovascular Calcification as a Marker of Increased Cardiovascular Risk and a Surrogate for Subclinical Atherosclerosis: Role of Echocardiography

The risk prediction of future cardiovascular events is mainly based on conventional risk factor assessment by validated algorithms, such as the Framingham Risk Score, the Pooled Cohort Equations and the European SCORE Risk Charts. The identification of subclinical atherosclerosis has emerged as a promising tool to refine the individual cardiovascular risk identified by these models, to prognostic stratify asymptomatic individuals and to implement preventive strategies. Several imaging modalities have been proposed for the identification of subclinical organ damage, the main ones being coronary artery calcification scanning by cardiac computed tomography and the two-dimensional ultrasound evaluation of carotid arteries. In this context, echocardiography offers an assessment of cardiac calcifications at different sites, such as the mitral apparatus (including annulus, leaflets and papillary muscles), aortic valve and ascending aorta, findings that are associated with the clinical manifestation of atherosclerotic disease and are predictive of future cardiovascular events. The aim of this paper is to summarize the available evidence on clinical implications of cardiac calcification, review studies that propose semiquantitative ultrasound assessments of cardiac calcifications and evaluate the potential of ultrasound calcium scores for risk stratification and prevention of clinical events.

Association of Carotid Artery Plaque With Cardiovascular Events and Incident Coronary Artery Calcium in Individuals With Absent Coronary Calcification: The MESA

BACKGROUND

Absence of coronary artery calcium (CAC) identifies asymptomatic individuals at low cardiovascular disease risk. Carotid artery plaque is a marker of increased risk, but its association with cardiovascular risk and incident CAC in people without CAC is unclear.

METHODS

Multi-Ethnic Study of Atherosclerosis participants with CAC score of 0 at enrollment who also underwent carotid plaque measurement using B-mode ultrasonography were prospectively followed for incident coronary heart disease, stroke, and cardiovascular disease events, and CAC (score >0 on up to 3 serial computed tomography scans). The association of carotid plaque presence and plaque score (Ln[score+1]) at baseline with cardiovascular events and incident CAC was evaluated with Cox proportional hazards regression models adjusted for demographics, risk factors, and statin use.

RESULTS

Among these 2673 participants (58 years, 64% women, 34% White, 30% Black, 24% Hispanic, and 12% Chinese), carotid plaque at baseline was observed in 973 (36%) and the median plaque score (range, 1-12) among those with plaque was 1. A total of 79 coronary heart disease, 80 stroke, and 151 cardiovascular disease events were observed during 16.1 years of follow-up. Carotid plaque presence and plaque score were independently associated with coronary heart disease risk (HRs, 1.66 [95% CI, 1.04-2.66]; and 1.48 [95% CI, 1.01-2.17], respectively) but not with stroke and cardiovascular disease risk. A total of 973 (36.4%) participants developed CAC over the evaluation period (median 9.3 years). Carotid plaque presence and plaque score were independently associated with incident CAC (HRs, 1.34 [95% CI, 1.18-1.54]; and 1.37 [95% CI, 1.21-1.54]), respectively.

CONCLUSIONS

The presence and extent of carotid plaque are associated with long-term coronary heart disease risk and incident CAC among middle-aged asymptomatic individuals with an initial CAC score of 0.

2021 Canadian Cardiovascular Society Guidelines for the Management of Dyslipidemia for the Prevention of Cardiovascular Disease in Adults

The 2021 guidelines primary panel selected clinically relevant questions and produced updated recommendations, on the basis of important new findings that have emerged since the 2016 guidelines. In patients with clinical atherosclerosis, abdominal aortic aneurysm, most patients with diabetes or chronic kidney disease, and those with low-density lipoprotein cholesterol ≥ 5 mmol/L, statin therapy continues to be recommended. We have introduced the concept of lipid/lipoprotein treatment thresholds for intensifying lipid-lowering therapy with nonstatin agents, and have identified the secondary prevention patients who have been shown to derive the largest benefit from intensification of therapy with these agents. For all other patients, we emphasize risk assessment linked to lipid/lipoprotein evaluation to optimize clinical decision-making. Lipoprotein(a) measurement is now recommended once in a patient's lifetime, as part of initial lipid screening to assess cardiovascular risk. For any patient with triglycerides ˃ 1.5 mmol/L, either non-high-density lipoprotein cholesterol or apolipoprotein B are the preferred lipid parameter for screening, rather than low-density lipoprotein cholesterol. We provide updated recommendations regarding the role of coronary artery calcium scoring as a clinical decision tool to aid the decision to initiate statin therapy. There are new recommendations on the preventative care of women with hypertensive disorders of pregnancy. Health behaviour modification, including regular exercise and a heart-healthy diet, remain the cornerstone of cardiovascular disease prevention. These guidelines are intended to provide a platform for meaningful conversation and shared-decision making between patient and care provider, so that individual decisions can be made for risk screening, assessment, and treatment.

Prevention of Coronary Artery Disease-Related Heart Failure: The Role of Computed Tomography Scan

During the past decade, coronary computed tomography angiography has emerged as the primary modality to noninvasively detect and rule out coronary artery disease. Therefore, this technique could play an important role in identifying patients at high risk of heart failure, considering the high prevalence of coronary artery disease in these patients. The latest technologies have also increased diagnostic accuracy, helping to close the gap with the other functional imaging modalities.

Use of Coronary Artery Calcium Scoring to Improve Cardiovascular Risk Stratification and Guide Decisions to Start Statin Therapy in People Living With HIV

BACKGROUND

Cardiovascular disease (CVD) risk assessment remains a critical step in guiding decisions to initiate primary prevention interventions in people living with HIV (PLWH).

SETTING

We investigated whether coronary artery calcium (CAC) scoring allowed a more accurate selection of patients who may benefit from statin therapy, compared with current risk assessment tools alone.

METHODS

Cross-sectional analysis of PLWH over 50 years old who underwent CAC scoring between 2009 and 2019. Framingham Risk score (FRS), QRISK2 and D:A:D scores were calculated for each participant at the time of CAC scoring and statin eligibility determined based on current European guidelines on the prevention of CVD in PLWH.

RESULTS

A total of 739 patients were included (mean age 56 ± 5, 92.8% male, 84% white). Among 417 (56.4%) candidates for statin therapy based on FRS ≥10%, 174 (23.5%) had no detectable calcification (CAC = 0). Conversely, 145 (19.6%) patients with detectable calcification (CAC > 0) were identified as low-risk (FRS < 10%). When compared with FRS, CAC scoring reclassified CVD risk in 43.1% of patients, 145 (19.6%) to a higher risk group that could benefit from statin therapy and 174 (23.5%) statin candidates to a lower risk group. QRISK2 and D:A:D scores performed similarly to FRS, underestimating the presence of significant coronary calcification in 21.1% and 24.9% respectively and overestimating risk in 16.9% and 18.8% patients with CAC = 0.

CONCLUSIONS

Establishing a decision-model based on the combination of conventional risk tools and CAC scoring improves risk assessment and the selection of PLWH who would benefit from statin therapy.

Coronary artery calcium scoring: an evidence-based guide for primary care physicians

Primary care physicians often must decide whether statin therapy would be appropriate (in addition to lifestyle modification) for managing asymptomatic individuals with borderline or intermediate risk for developing atherosclerotic cardiovascular disease (ASCVD), as assessed on the basis of traditional risk factors. In appropriate subjects, a simple, noninvasive measurement of coronary artery calcium can help clarify risk. Coronary atherosclerosis is a chronic inflammatory disease, with atherosclerotic plaque formation involving intimal inflammation and repeated cycles of erosion and fibrosis, healing and calcification. Atherosclerotic plaque formation represents the prognostic link between risk factors and future clinical events. The presence of coronary artery calcification is almost exclusively an indication of coronary artery disease, except in certain metabolic conditions. Coronary artery calcification can be detected and quantified in a matter of seconds by noncontrast electrocardiogram-gated low-dose X-ray computed tomography (coronary artery calcium scoring [CACS]). Since the publication of the seminal work by Dr. Arthur Agatston in 1990, a wealth of CACS-based prognostic data has been reported. In addition, recent guidelines from various professional societies conclude that CACS may be considered as a tool for reclassifying risk for atherosclerotic cardiovascular disease in patients otherwise assessed to have intermediate risk, so as to more accurately inform decisions about possible statin therapy in addition to lifestyle modification as primary preventive therapy. In this review, we provide an overview of CACS, from acquisition to interpretation, and summarize the scientific evidence for and the appropriate use of CACS as put forth in current clinical guidelines.

The role of cardiac computed tomography in pre-participation screening of mature athletes

The overwhelming majority of sports-related sudden cardiac deaths in mature athletes is attributed to coronary artery disease (CAD). Coronary plaques of mature athletes appear to be more calcified compared to sedentary individuals and thus may be more stable and less likely to be associated with an acute coronary event. Cardiac computed tomography (CT), including unenhanced CT for coronary artery calcium scoring (CACS) and contrast-enhanced coronary CT angiography, is characterized by very high negative predictive value to rule out CAD. Cardiac CT has been shown to have additional diagnostic value for detection of CAD in athletes over and above exercise electrocardiogram. Moreover, measurement of CACS possibly enables a more precise cardiovascular risk stratification of mature athletes. The main advantage of cardiac CT is its noninvasive nature. Although cardiac CT appears to increase the overall cost of cardiac examinations, this additional cost is much lower than the cost of unnecessary invasive coronary angiographies that would be performed in case of false positive results of exercise electrocardiograms. Radiation exposure may not be a major concern for the application of this modality to pre-participation screening of athletes, since recent technical advancements have resulted in low radiation dose of cardiac CT.Highlights Coronary computed tomography angiography can be used in pre-participation screening of mature athletes to increase the negative predictive value for excluding coronary artery disease.The identification of coronary artery calcium score = 0 in an athlete can improve risk stratification, since this athlete can be reasonably managed as an individual with low cardiovascular risk.

New Model for Predicting the Presence of Coronary Artery Calcification

Coronary artery calcification (CAC) is a feature of coronary atherosclerosis and a well-known risk factor for cardiovascular disease (CVD). As the absence of CAC is associated with a lower incidence rate of CVD, measurement of a CAC score is helpful for risk stratification when the risk decision is uncertain. This was a retrospective study with an aim to build a model to predict the presence of CAC (i.e., CAC score = 0 or not) and evaluate the discrimination and calibration power of the model. Our data set was divided into two set (80% for training set and 20% for test set). Ten-fold cross-validation was applied with ten times of interaction in each fold. We built prediction models using logistic regression (LRM), classification and regression tree (CART), conditional inference tree (CIT), and random forest (RF). A total of 3,302 patients from two cohorts (Soonchunhyang University Cheonan Hospital and Kangbuk Samsung Health Study) were enrolled. These patients' ages were between 40 and 75 years. All models showed acceptable accuracies (LRM, 70.71%; CART, 71.32%; CIT, 71.32%; and RF, 71.02%). The decision tree model using CART and CIT showed a reasonable accuracy without complexity. It could be implemented in real-world practice.

Prevalence and Functional Implication of Silent Coronary Artery Disease in Marathon Runners Over 40 Years of Age: The MATCH-40 Study

Background

Marathon participation is becoming increasingly popular among individuals ≥40 years of age. Little is known about the prevalence of subclinical coronary artery disease (CAD) and corresponding ischemia in this patient population. The study objectives are: (1) to characterize the prevalence of silent CAD in marathoners ≥ 40 years old using cardiac computed tomography angiography (CCT); and (2) if subclinical CAD was detected, to determine the functional significance of occult lesions by stress echocardiography (SE).

Methods

Marathoners aged ≥ 40 years who completed a full marathon between 2018 and 2019 were recruited to undergo a prospective CCT. Coronary artery stenosis was graded as zero, mild (1%-49%), moderate (50%-69%), or severe (> 70%). All study participants diagnosed with mild-to-severe atherosclerotic CAD on CCT further underwent functional imaging with exercise treadmill SE.

Results

A total of 65 individuals (53 ± 7 years, 65% males, 24 ± 3 kg/m²) underwent a prospective CCT within 12 months of marathon completion. Of the total study population, 13 participants (20%) were diagnosed with CAD, of whom 10 (77%) had mild disease, 1 (8%) had moderate disease, and 2 (15%) had severe disease by CCT. Despite the identification of subclinical CAD on CCT, none of the 13 patients had any evidence of inducible ischemia on SE.

Conclusions

This is the first study to incorporate both CCT and SE in the evaluation of subclinical CAD in marathoners ≥40 years old. Although the overall prevalence of anatomic CAD was 20%, there was no evidence of functional ischemia in this highly competitive cohort.

Vascular imaging of atherosclerosis: Strengths and weaknesses

Atherosclerosis is an inflammatory disease that can lead to several complications such as ischemic heart disease, stroke, and peripheral vascular disease. Therefore, researchers and clinicians rely heavily on the use of imaging modalities to identify, and more recently, quantify the burden of atherosclerosis in the aorta, carotid arteries, coronary arteries, and peripheral vasculature. These imaging techniques vary in invasiveness, cost, resolution, radiation exposure, and presence of artifacts. Consequently, a detailed understanding of the risks and benefits of each technique is crucial prior to their introduction into routine cardiovascular screening. Additionally, recent research in the field of microvascular imaging has proven to be important in the field of atherosclerosis. Using techniques such as contrast-enhanced ultrasound and superb microvascular imaging, researchers have been able to detect blood vessels within a plaque lesion that may contribute to vulnerability and rupture. This paper will review the strengths and weaknesses of the various imaging techniques used to measure atherosclerotic burden. Furthermore, it will discuss the future of advanced imaging modalities as potential biomarkers for atherosclerosis.

The National Lipid Association scientific statement on coronary artery calcium scoring to guide preventive strategies for ASCVD risk reduction

An Expert Panel of the National Lipid Association reviewed the evidence related to the use of coronary artery calcium (CAC) scoring in clinical practice for adults seen for primary prevention of atherosclerotic cardiovascular disease. Recommendations for optimal use of this test in adults of various races/ethnicities, ages and multiple domains of primary prevention, including those with a 10-year ASCVD risk <20%, those with diabetes or the metabolic syndrome, and those with severe hypercholesterolemia were provided. Recommendations were also made on optimal timing for repeat calcium scoring after an initial test, use of CAC scoring in those taking statins, and its role in informing the clinician patient discussion on the benefit of aspirin and anti-hypertensive drug therapy. Finally, a vision is provided for the future of coronary calcium scoring.

Epidemiological Research Advances in Vascular Calcification in Diabetes

Vascular calcification is the transformation of arterial wall mesenchymal cells, particularly smooth muscle cells (SMCs), into osteoblast phenotypes by various pathological factors. Additionally, vascular transformation mediates the abnormal deposition of calcium salts in the vascular wall, such as intimal and media calcification. Various pathological types have been described, such as calcification and valve calcification. The incidence of vascular calcification in patients with diabetes is much higher than that in nondiabetic patients, representing a critical cause of cardiovascular events in patients with diabetes. Because basic research on the clinical transformation of vascular calcification has yet to be conducted, this study systematically expounds on the risk factors for vascular calcification, vascular bed differences, sex differences, ethnic differences, diagnosis, severity assessments, and treatments to facilitate the identification of a new entry point for basic research and subsequent clinical transformation regarding vascular calcification and corresponding clinical evaluation strategies.

Statin Treatment in Specific Patient Groups: Role for Improved Cardiovascular Risk Markers

Ample evidence supports the use of statin therapy for secondary prevention in patients with a history of atherosclerotic cardiovascular disease (ASCVD), but evidence is wanting in the case of primary prevention, low-risk individuals, and elderly adults 65+. Statins are effective in lowering low-density lipoprotein (LDL), which has long been a target for treatment decisions. We discuss the weakening dependence between cholesterol levels and mortality as a function of age and highlight recent findings on lipoprotein subfractions and other superior markers of ASCVD risk. The efficacy of statins is compared for distinct subsets of patients based on age, diabetes, ASCVD, and coronary artery calcium (CAC) status. Most cardiovascular risk calculators heavily weight age and overestimate one's absolute risk of ASCVD, particularly in very old adults. Improvements in risk assessment enable the identification of specific patient populations that benefit most from statin treatment. Derisking is particularly important for adults over 75, in whom treatment benefits are reduced and adverse musculoskeletal effects are amplified. The CAC score stratifies the benefit effect size obtainable with statins, and forms of coenzyme Q are discussed for improving patient outcomes. Robust risk estimator tools and personalized, evidence-based approaches are needed to optimally reduce cardiovascular events and mortality rates through administration of cholesterol-lowering medications.

Coronary Artery Calcium to Improve the Efficiency of Randomized Controlled Trials in Primary Cardiovascular Prevention

OBJECTIVES

This study sought to assess the value, in terms of sample size and cost, of using the coronary artery calcium (CAC) score to enrich the study population of primary prevention randomized controlled trials (RCTs) with participants at high absolute risk of atherosclerotic cardiovascular disease (ASCVD) events.

BACKGROUND

The feasibility of RCTs assessing the efficacy of novel add-on therapies for primary prevention among high-risk individuals treated with statins may be limited by sample size and cost.

METHODS

We evaluated 3,075 statin-naive participants from the MESA (Multi-Ethnic Study of Atherosclerosis) with estimated 10-year ASCVD risk of ≥7.5%. CAC of >100, CAC of >400, high sensitivity C-reactive protein levels of >2 and >3 mg/l, ankle-brachial index of <0.9, and triglyceride levels of >175 mg/dl were each evaluated as enrichment criteria on top of estimated ASCVD risk of ≥7.5%, ≥10%, ≥15% and ≥20%. For each criterion, using the observed 5-year incidence of CVD, we projected the incidence of CVD assuming a 28% relative risk reduction with high-intensity statin therapy and after addition of novel therapy with additive relative risk reductions of 15% and 25%. Sample size and cost of a hypothetical primary prevention 5-year RCT of a novel therapy on top of statins versus statins alone were then computed by using the projected incidences. Yearly costs per included participant of $6,000 to $9,000 and of $500/$600 per screened nonparticipant were assumed.

RESULTS

CAC of >400, present in 15% to 23% participants, consistently identified the subgroups with highest 5-year incident events and outperformed the other features yielding the smallest projected sample size, ranging 33% to 58% lower than using risk estimations alone for participant selection. CAC of >400 also yielded the lowest projected RCT costs, at least $40 million lower than using risk estimations alone. CAC of >100 showed the second-best performance in most scenarios.

CONCLUSIONS

High CAC scores used as study entry criteria can improve the efficiency and feasibility of primary prevention RCTs evaluating the incremental efficacy of novel add-on therapies.

Can post-mortem coronary artery calcium scores aid diagnosis in young sudden death?

This study sought to explore the feasibility and utility of post-mortem coronary artery calcium (CAC) scoring in identifying patients with ischemic heart disease as cause of sudden death. 100 deceased patients aged 18-50 years underwent post-mortem examination in the setting of sudden death. At post-mortem, fifty cases were determined to have ischemic heart disease, and fifty had death attributed to trauma or unascertained causes. The CAC score was calculated in a blinded manner from post-mortem CTs performed on all cases. CAC scores were assessable in 97 non-decomposed cases (feasibility 97%). The median CAC score was 88 Agatston units [IQR 0-286] in patients deceased from ischemic heart disease vs 0 [IQR 0-0] in patients deceased from other causes (p < 0.0001). Presence of any coronary calcification differed significantly between ischemic heart disease and non-ischemic groups (adjusted odds ratio 10.7, 95% CI 3.2-35.5). All cases with a CAC score > 100 (n = 22) had ischemic heart disease as the cause of death. Fifteen cases had a CAC score of zero but severe coronary disease at post-mortem examination. Post-mortem CAC scoring is highly feasible. An elevated CAC score in cases 18-50 years old with sudden death predicts ischemic heart disease at post-mortem examination. However, a CAC score of zero does not exclude significant coronary artery disease. Post-mortem CAC score may be considered as a further assessment tool to help predict likely cause of death when there is an objection to or unavailability of post-mortem examination.

Warranty Period of a Calcium Score of Zero: Comprehensive Analysis From MESA

OBJECTIVES

This study sought to quantify and model conversion of a normal coronary artery calcium (CAC) scan to an abnormal CAC scan.

BACKGROUND

Although the absence of CAC is associated with excellent prognosis, progression to CAC >0 confers increased risk. The time interval for repeated scanning remains poorly defined.

METHODS

This study included 3,116 participants from the MESA (Multi-Ethnic Study of Atherosclerosis) with baseline CAC = 0 and follow-up scans over 10 years after baseline. Prevalence of incident CAC, defined by thresholds of CAC >0, CAC >10, or CAC >100, was calculated and time to progression was derived from a Weibull parametric survival model. Warranty periods were modeled as a function of sex, race/ethnicity, cardiovascular risk, and desired yield of repeated CAC testing. Further analysis was performed of the proportion of coronary events occurring in participants with baseline CAC = 0 that preceded and followed repeated CAC testing at different time intervals.

RESULTS

Mean participants' age was 58 ± 9 years, with 63% women, and mean 10-year cardiovascular risk of 14%. Prevalence of CAC >0, CAC >10, and CAC >100 was 53%, 36%, and 8%, respectively, at 10 years. Using a 25% testing yield (number needed to scan [NNS] = 4), the estimated warranty period of CAC >0 varied from 3 to 7 years depending on sex and race/ethnicity. Approximately 15% of participants progressed to CAC >10 in 5 to 8 years, whereas 10-year progression to CAC >100 was rare. Presence of diabetes was associated with significantly shorter warranty period, whereas family history and smoking had small effects. A total of 19% of all 10-year coronary events occurred in CAC = 0 prior to performance of a subsequent scan at 3 to 5 years, whereas detection of new CAC >0 preceded 55% of future events and identified individuals at 3-fold higher risk of coronary events.

CONCLUSIONS

In a large population of individuals with baseline CAC = 0, study data provide a robust estimation of the CAC = 0 warranty period, considering progression to CAC >0, CAC >10, and CAC >100 and its impact on missed versus detectable 10-year coronary heart disease events. Beyond age, sex, race/ethnicity, diabetes also has a significant impact on the warranty period. The study suggests that evidence-based guidance would be to consider rescanning in 3 to 7 years depending on individual demographics and risk profile.

Coronary artery anomalies in patients with zero calcium score: A new evidence supports the 2016-NICE guidance

Background

Currently, guidelines from around the world endorse measurement of coronary artery calcium (CAC) to improve clinical risk prediction in appropriately selected asymptomatic and stable symptomatic individuals. A CAC score of zero may discourage from further testing as coronary computed tomography angiography (CCTA). We investigate the presence of malignant coronary artery anomalies (CAA)s among stable symptomatic patients with zero CAC.

Methods

A total of 281 individuals' information was obtained. These individuals had low to intermediate pre-test probability of coronary artery disease, complained of stable typical or atypical chest pain, were not known to have CAD, and had CAC scan score of zero. After investigating the CCTA, Angelini's classification system for CAA was utilized in adapted form to determine the presence, the class and type of the CAA.

Results

The CAAs were detected in 16 (5.7 %) patients on CCTA, 15 (8.1 %) of them were below 45 years. The mean age for patients with CAAs was 31.8. According to Angelini classification system, most of the detected CAAs were malignant such as the origination of the coronary artery from the opposite sinus with arterial course between the aortic and pulmonary trunks and the intramural muscular bridge course.

Conclusion

It is preferable to perform CCTA in young patients with cardiac symptoms, especially in Asian and Middle Eastern countries even of the CAC score is zero.

Prognostic value of cardiac CT

In the past decades, coronary computed tomography angiography (CCTA) has become a powerful tool in the management of coronary artery disease. The diagnostic and prognostic value of CCTA has been extensively demonstrated in both large observational studies and clinical trials among stable chest pain patients. The quantification of coronary artery calcium score (CACS) is a well-established predictor of cardiovascular morbidity and mortality in asymptomatic subjects. Besides CACS, the main strength of CCTA is the accurate assessment of the individual total atherosclerotic plaque burden, which holds important prognostic information. In addition, CCTA, by providing detailed information on coronary plaque morphology and composition with identification of specific high-risk plaque features, may further improve the risk stratification beyond the assessment of coronary stenosis. The development of new CCTA applications, such as stress myocardial CT perfusion and computational fluids dynamic applied to standard CCTA to derive CT-based fractional flow reserve (FFR) values have shown promising results to guide revascularization, potentially improving clinical outcomes in stable chest pain patients. In this review, starting from the role of CACS and moving beyond coronary stenosis, we evaluate the existing evidence of the prognostic effectiveness of the CCTA strategy in real-world clinical practice.

Coronary artery calcium testing in low-intermediate risk symptomatic patients with suspected coronary artery disease: An effective gatekeeper to further testing?

Computed tomography for quantification of coronary artery calcium (CAC) is a simple non-invasive tool to assess atherosclerotic plaque burden. CAC is highly correlated with coronary atherosclerosis and is a robust predictor of cardiovascular outcomes. Recently, the 2018 ACC/AHA Cholesterol Guidelines endorsed the use of CAC scores in asymptomatic, intermediate risk individuals where the decision to initiate stain therapy is uncertain. However, whether quantification of CAC may play a role in the assessment of symptomatic individuals remains a matter of debate. In this review, we examine the evidence for the use of CAC in low-intermediate risk patients with chest pain. This appraisal places a particular focus on the growing body of literature supporting the negative predictive value of a CAC score of zero to rule out significant coronary artery disease in those without high-risk features. We also evaluate current guidelines, limitations, and future research directions for CAC scoring in this important subgroup of patients.

Machine Learning-based Algorithm Enables the Exclusion of Obstructive Coronary Artery Disease in the Patients Who Underwent Coronary Artery Calcium Scoring

RATIONALE AND OBJECTIVES

An application of artificial intelligence to screen for obstructive coronary artery disease (CAD) after coronary artery calcium scoring (CACS) test.

MATERIALS AND METHODS

As an initial step we analyzed a group of 435 patients (23% male, mean age 61 ± 10) with low to moderate probability of CAD, who underwent clinically indicated CACS and coronary computed tomography angiography. Based on those data we elaborated a gradient boosting machine (GBM) model for prediction of obstructive CAD. Later the model was evaluated on a control group of 126 consecutive patients (31% male, mean age 59 ± 10).

RESULTS

Stratified 10-fold cross-validation performed on the group of 435 patients demonstrated the GBM model's sensitivity at 100 ± 0% and specificity at 69.8 ± 3.6%, while the outcomes (confusion matrix) of a clinical application on the group of 126 patients were: 73 true negative, 0 false negative, 20 true positive, and 33 false positive.

CONCLUSION

The GBM algorithm showcased a considerably high discriminatory power for excluding the presence of obstructive CAD, with negative predictive value and positive predictive value of 100% and 38%, respectively.

Radio-induced cardiotoxicity: From physiopathology and risk factors to adaptation of radiotherapy treatment planning and recommended cardiac follow-up

Cancer and cardiovascular disease (CVD) are the leading cause of mortality worldwide, and breast cancer (BC) the most common malignancy affecting women worldwide. Radiotherapy is an important component of BC treatment and participates in CVD occurrence. It seems, therefore, crucial to gather both radiation oncology and cardiology medical fields to improve the follow-up quality of our BC patients. This review aims at updating our knowledge regarding cardiotoxicities risk factors, and consequently, doses constraints in case of 3D-conformal and IMRT treatment planning. Then we will develop how to reduce cardiac exposure and what kind of cardiac follow-up we could recommend to our breast cancer patients.

Prevalence of coronary artery disease in symptomatic patients with zero coronary artery calcium score in different age population

There is controversy about whether symptomatic population with coronary artery calcium score (CACS) of zero have coronary artery disease (CAD) and the distribution at different ages. We sought to analyze the prevalence of CAD in symptomatic patients with zero CACS, especially in different age groups. We studied patients suspected of CAD and underwent CACS scan and coronary computed tomography angiography (CTA). We included patients with CACS of zero. Clinical data was collected to achieve information on demographic characteristics and risk factors. The presence of plaque and obstructive CAD were analyzed based on coronary CTA. The association between age and the prevalence of plaque and obstructive CAD was evaluated.Overall 5514 patients (51.1% men; mean age 54.40 years) were analyzed, of whom 4120 (74.72%) with normal coronary artery, 1394 (25.28%) with plaque and 514 (9.32%) with obstructive CAD. The prevalence of plaque and obstructive CAD increased significantly with age (p < 0.001). Age was significantly associated with the risk of developing plaque and obstructive CAD in the unadjusted model and multivariate model. Taking age less than 40 as a reference, risk ratios (RRs) of prevalence of plaque increased with age in the multivariate model (RR = 2.353 for 40-50, RR = 6.489 for > 70). RRs of prevalence of obstructive CAD also increased with age in the multivariate model (RR = 2.075 for 40-50, RR = 4.102 for > 70). Quite a few CAD could occur in symptomatic patients with CACS of zero, especially in old patients. Coronary CTA was required to exclude CAD in this cohort.

Cardiac-CT and cardiac-MR cost-effectiveness: a literature review

Cardiovascular diseases are still among the first causes of death worldwide with a huge impact on healthcare systems. Within these conditions, the correct diagnosis of coronary artery disease with the most appropriate imaging-based evaluations is of utmost importance. The sustainability of the healthcare systems, considering the high economic burden of modern cardiac imaging equipments, makes cost-effective analysis an important tool, currently used for weighing different costs and health outcomes, when policy makers have to allocate funds and to prioritize interventions, getting the most out of their financial resources. This review aims at evaluating cost-effective analysis in the more recent literature, focused on the role of Calcium Score, coronary computed tomography angiography and cardiac magnetic resonance.

Measurement of coronary artery calcium volume using ultra-high-resolution computed tomography: A preliminary phantom and cadaver study

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Small calcifications were moe accurately detectable on SHR- than NR images.

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The mean CAC volume was significantly higher on SHR- than NR images of the cadavers.

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SHR imaging may facilitate the accurate quantification of the CAC.

Objectives

In this phantom- and cadaver study we investigated the differences of coronary artery calcium (CAC) volume on ultra-high-resolution computed tomography (U-HRCT) scans and conventional CT.

Methods

We scanned a coronary calcium phantom and the coronary arteries of five cadavers using U-HRCT in normal- and super-high resolution (NR, SHR) mode. The NR mode was similar to conventional CT; 896 detector channels, a matrix size of 512, and a slice thickness of 0.5 mm were applied. In SHR mode, we used 1792 detector channels, a matrix size of 1024, and a slice thickness of 0.25 mm. The CAC volume on NR- and SHR images were recorded. Differences in the physical- and the calculated CAC volume were defined as the error value and compared between NR- and SHR images of the phantom. Differences between the CAC volume on NR- and SHR scans of the cadavers were also recorded.

Results

The mean error value was lower on SHR- than NR images of the phantom (14.0 %, SD 11.1 vs 20.1 %, SD 15.2, p = 0.01). The mean CAC volume was significantly higher on SHR- than NR images of the cadavers (153.4 mm³, SD 161.0 vs 144.7 mm³, SD 164.8, p < 0.01).

Conclusions

As small calcifications were more clearly visualized on U-HRCT images in SHR mode than on conventional (NR) CT scans, SHR imaging may facilitate the accurate quantification of the CAC.

Non-invasive imaging of the coronary arteries

Non-invasive imaging of the coronary arteries is an enterprise in rapid development. From the research perspective, there is great demand for in vivo techniques that can reliably identify features of high-risk plaque that may offer insight into pathophysiological processes and act as surrogate indicators of response to therapeutic intervention. Meanwhile, there is clear clinical need for greater accuracy in diagnosis and prognostic stratification. Fortunately, ongoing technological improvements and emerging data from randomized clinical trials are helping make these elusive goals a reality. This review provides an update on the current status of non-invasive coronary imaging with computed tomography, magnetic resonance, and positron emission tomography with a focus on current clinical applications and future research directions.

Impact of rheumatoid arthritis on major cardiovascular events in patients with and without coronary artery disease

INTRODUCTION

Rheumatoid arthritis (RA) is a risk factor for cardiovascular disease. The clinical consequences of coincident RA and coronary artery disease (CAD) are unknown.

OBJECTIVE

We aimed to estimate the impact of RA on the risk of adverse cardiovascular events in patients with and without CAD.

METHODS

A population-based cohort of patients registered in the Western Denmark Heart Registry, who underwent coronary angiography (CAG) between 2003 and 2016, was stratified according to the presence of RA and CAD. Endpoints were myocardial infarction (MI), major adverse cardiovascular events (MACE; MI, ischaemic stroke and cardiac death) and all-cause mortality.

RESULTS

A total of 125 331 patients were included (RA: n=1732). Median follow-up was 5.2 years. Using patients with neither RA nor CAD as reference (cumulative MI incidence 2.7%), the 10-year risk of MI was increased for patients with RA alone (3.8%; adjusted incidence rate ratio (IRR_adj) 1.63, 95% CI 1.04 to 2.54), for patients with CAD alone (9.9%; IRR_adj 3.35, 95% CI 3.10 to 3.62), and highest for patients with both RA and CAD (12.2%; IRR_adj 4.53, 95% CI 3.66 to 5.59). Similar associations were observed for MACE an all-cause mortality.

CONCLUSIONS

In patients undergoing CAG, RA is significantly associated with the 10-year risk of MI, MACE and all-cause mortality regardless of the presence of CAD. However, patients with RA and CAD carry the largest risk, while the additive risk of RA in patients without CAD is minor. Among patients with RA, risk stratification by presence or absence of documented CAD may allow for screening and personalised treatment strategies.

Coronary artery calcification, carotid intima-media thickness and cardiac dysfunction in young adults with type 2 diabetes mellitus

AIMS

Cardiovascular diseases (CVD) are the major causes of mortality in patients with type 2 diabetes mellitus (T2DM). There is paucity of information on prevalence of subclinical atherosclerosis and cardiac dysfunction in young adults with T2DM. This study aimed to assess the prevalence of subclinical atherosclerosis and cardiac dysfunction in young adults with T2DM, asymptomatic for CVD.

METHODS

Sixty-two patients with T2DM, age between 30 and 50 years were evaluated for coronary artery calcium (CAC) score, carotid intima-media thickness (CIMT) and flow-mediated dilatation (FMD) at the brachial artery. All were subjected to 2D-color Doppler echocardiography, electrocardiography and testing for serum N-terminal pro-brain natriuretic peptide (NT-proBNP) and high-sensitivity C-reactive protein (hsCRP). The results were compared with those in 60 age, sex and BMI-matched healthy controls.

RESULTS

Prevalence of a positive CAC score was comparable among subjects with and without T2DM (14.5% vs 11.7%). Patients with T2DM had a significantly higher CIMT (0.54 ± 0.15 vs 0.49 ± 0.10 mm, p = 0.01), left ventricular (LV) mass (170 ± 36 vs 147 ± 23 g, p < 0.001), heart rate (83 ± 13 vs 74 ± 11, p < 0.001) and QTc interval (402 ± 20 vs 382 ± 21 ms, p < 0.001) compared to controls. FMD was lower in patients with T2DM compared to controls (9.1 ± 4.4% vs 10.7 ± 3.9%, p = 0.04). There was a higher prevalence of LV hypertrophy (37% vs 7%, p < 0.001) and diastolic dysfunction (7% vs 0) in patients with T2DM compared to controls. None of the participants had systolic dysfunction. Hypertension (42 vs 7%, p < 0.001) and metabolic syndrome (76 vs 35%, p < 0.001) were more prevalent in the patient group. In the multivariate analysis, age was the lone predictor of CIMT and FMD; while T2DM and male gender were the independent predictors of LV mass.

CONCLUSIONS

Young adults with T2DM, asymptomatic for CVD had a higher prevalence of CVD risk factors, LV hypertrophy and diastolic dysfunction. A higher CIMT and LV mass, and a lower FMD were noted in patients with T2DM. CAC score was comparable between the groups and thus may not be a useful tool for assessment of subclinical atherosclerosis in this cohort, where CIMT and FMD may be more appropriate.

Atherosclerotic Cardiovascular Disease Risk Stratification Based on Measurements of Troponin and Coronary Artery Calcium

BACKGROUND

Low values of high-sensitivity cardiac troponin (hs-cTn) and coronary artery calcium (CAC) scores of zero are associated with a low risk for atherosclerotic cardiovascular disease (ASCVD).

OBJECTIVES

The purpose of this study was to evaluate baseline hs-cTnT and CAC in relation to ASCVD.

METHODS

Baseline hs-cTnT (limit of detection [LoD] 3 ng/l) and CAC measurements were analyzed across participants age 45 to 84 years without clinical cardiovascular disease from the prospective MESA (Multi-Ethnic Study of Atherosclerosis) in relationship to incident ASCVD.

RESULTS

Among 6,749 participants, 1,002 ASCVD events occurred during a median follow-up of 15 years. Participants with detectable CAC (20.1 vs. 5.0 events per 1,000 person-years; adjusted hazard ratio [HR]: 2.35; 95% confidence interval [CI]: 2.0 to 2.76; p < 0.001) and detectable hs-cTnT (15.4 vs. 5.2 per 1,000 person-years; adjusted HR: 1.47; 95% CI: 1.21 to 1.77; p < 0.001) had higher rates of ASCVD than those with undetectable results. Individuals with undetectable hs-cTnT (32%) had similar risk for ASCVD as did those with a CAC of zero (50%) (5.2 vs. 5.0 per 1,000 person-years). Together, hs-cTnT and CAC (discordance 38%) resulted in the following ASCVD event rates: hs-cTnT < LoD/CAC = 0: 2.8 per 1,000 person-years (reference), hs-cTnT ≥ LoD/CAC = 0: 6.8 per 1,000 person-years (HR: 1.59; 95% CI: 1.17 to 2.16; p = 0.003), hs-cTnT < LoD/CAC > 0: 11.1 per 1,000 person-years (HR: 2.74; 95% CI: 1.96 to 3.83; p < 0.00001), and hs-cTnT ≥ LoD/CAC > 0: 22.6 per 1,000 person-years (HR: 3.50; 95% CI: 2.60 to 4.70; p < 0.00001).

CONCLUSIONS

An undetectable hs-cTnT identifies patients with a similar, low risk for ASCVD as those with a CAC score of zero. The increased risk among those with discordant results supports their conjoined use for risk prediction.

Coronary Calcium Characteristics as Predictors of Major Adverse Cardiac Events in Symptomatic Patients: Insights From the CORE 320 Multinational Study

Background

The predictive value of coronary artery calcium (CAC) has been widely studied; however, little is known about specific characteristics of CAC that are most predictive. We aimed to determine the independent associations of Agatston score, CAC volume, CAC area, CAC mass, and CAC density score with major adverse cardiac events in patients with suspected coronary artery disease.

Methods and Results

A total of 379 symptomatic participants, aged 45 to 85 years, referred for invasive coronary angiography, who underwent coronary calcium scanning and computed tomography angiography as part of the CORE320 (Combined Noninvasive Coronary Angiography and Myocardial Perfusion Imaging Using 320 Detector Computed Tomography) study, were included. Agatston score, CAC volume, area, mass, and density were computed on noncontrast images. Stenosis measurements were made on contrast‐enhanced images. The primary outcome of 2‐year major adverse cardiac events (30 revascularizations [>182 days of index catheterization], 5 myocardial infarctions, 1 cardiac death, 9 hospitalizations, and 1 arrhythmia) occurred in 32 patients (8.4%). Associations were estimated using multivariable proportional means models. Median age was 62 (interquartile range, 56–68) years, 34% were women, and 56% were white. In separate models, the Agatston, volume, and density scores were all significantly associated with higher risk of major adverse cardiac events after adjustment for age, sex, race, and statin use; density was the strongest predictor in all CAC models. CAC density did not provide incremental value over Agatston score after adjustment for diameter stenosis, age, sex, and race.

Conclusions

In symptomatic patients, CAC density was the strongest independent predictor of major adverse cardiac events among CAC scores, but it did not provide incremental value beyond the Agatston score after adjustment for diameter stenosis.

Rheumatoid Arthritis as a Risk Factor for Coronary Artery Calcification and Obstructive Coronary Artery Disease in Patients with Chest Pain: A Registry Based Cross-Sectional Study

Purpose

To examine the occurrence and severity of coronary artery disease (CAD) in patients with rheumatoid arthritis (RA) compared to non-RA patients in a population referred for coronary computed tomography angiography (CTA) due to chest pain.

Patients and Methods

In this cross-sectional study, 46,210 patients from a national CTA database were included. Patients with RA were stratified on serology, treatment with conventional synthetic or biological disease-modifying antirheumatic drugs (DMARDs), and the need for relapse or flare treatment with intraarticular or -muscular glucocorticoid injections (GCIs). Primary outcomes were coronary artery calcium score (CACS) >0 and CACS ≥400, and secondary outcome was obstructive CAD. Associations between RA and outcomes were examined using logistic regression and results were adjusted for age, sex, cardiovascular risk factors and comorbidities.

Results

A total of 395 (0.9%) RA patients were identified. In overall RA, crude odds ratio (OR) for having CACS >0 was 1.48 (1.21–1.82) and 1.52 (1.15–2.01) for CACS ≥400, whereas adjusted ORs were 1.08 (0.86–1.36) and 1.21 (0.89–1.65), respectively. Seropositive RA patients had adjusted OR of 1.16 (0.89–1.50) for CACS >0 and 1.37 (0.98–1.90) for CACS ≥400. Patients who had received ≥1 GCI in the period of 3 years prior to the CTA had an adjusted OR of 1.37 (0.94–2.00) for having CACS >0 and 1.46 (0.92–2.31) for CACS ≥400.

Conclusion

This is the first large-scale, CTA-based study examining the occurrence and severity of CAD in RA patients with symptoms suggestive of cardiovascular disease. A higher prevalence of coronary artery calcification was found in RA patients. After adjusting for age, sex, cardiovascular risk factors and comorbidities, the tendency was less pronounced. We found a trend for increased coronary calcification in RA patients being seropositive or needing treatment with GCI for a relapse or flare.

Usefulness of Findings by Multimodality Imaging to Stratify Risk of Major Adverse Cardiac Events After Sepsis at 1 and 12 months

Cardiovascular complications are reported in up to 30% of sepsis survivors. Currently, there is limited evidence to guide cardiovascular risk stratification of septic patients. We propose the use of left ventricular ejection fraction (LVEF) and coronary artery calcification (CAC) on nongated computed tomography (CT) scans to identify septic patients at highest risk for major adverse cardiovascular events (MACE). We retrospectively reviewed 517 adult patients with sepsis, elevated troponin levels, nongated CT scans that visualized the coronaries, and an echocardiogram. Patients were stratified into 4 groups based on the LVEF and presence or absence of CAC. Using the CAC negative/LVEF ≥ 50% as a control, we compared MACE and all-cause mortality outcomes across the patient groups. At 30 days, 39 patients (7.5%) experienced MACE and 166 patients (32%) died. Patients with no CAC and LVEF ≥ 50% experienced no MACE at 30 days or 1 year. Among patients with EF < 50%, CAC positive or negative patients were statistically more likely to experience a MACE event at 30 days (p < 0.001 for both groups). After 30 days, a further 6 patients (1.2%) experienced MACE and 66 (12.7%) patients died within the first year. Patients with CAC positive/LVEF < 50% experienced the highest rates of MACE at 1 year (p < 0.001). In conclusion, the combination of LVEF on echocardiography and CAC on nongated CT scans provides a powerful risk stratification tool for predicting cardiovascular events in septic patients.

A tale of two technologies: Can nuclear cardiology survive the emergence of cardiac CT the seventeenth annual Mario S. Verani lectureship

The Mario S. Verani Lectureship has traditionally been an opportunity for presenters to reflect on the state of nuclear cardiology in clinical practice and expound on new innovations in the field. Mario Verani was a visionary who embraced change and, as a cardiologist, sought to define where other cardiac imaging techniques might complement nuclear cardiology for improving patient care. Over the last decade, nuclear cardiology and cardiac computed tomography (CT) have developed in parallel with both expanding beyond the evaluation of coronary artery disease. However, many consider cardiac CT a formidable threat to nuclear cardiology due to pivotal technical innovations and its subsequent exponential growth in recent years. It is only fitting that this year's lectureship explore the relative value of both techniques in evaluating and managing cardiac disease, their relative strengths and weaknesses, and the potential value of combining nuclear cardiology and cardiac CT imaging for enhancing patient management. To Mario, my mentor, colleague for over 20 years and friend, this lectureship is truly in honor and remembrance of you.

High-pitch dual-source CT for coronary artery calcium scoring: A head-to-head comparison of non-triggered chest versus triggered cardiac acquisition

BACKGROUND

To determine the effect of low-dose, high-pitch non-electrocardiographic (ECG)-triggered chest CT on coronary artery calcium (CAC) detection, quantification and risk stratification, compared to ECG-triggered cardiac CT.

METHODS

We selected 1,000 participants from the ImaLife study, 50% with coronary calcification on cardiac CT. All participants underwent non-contrast cardiac CT followed by chest CT using third-generation dual-source technology. Reconstruction settings were equal for both acquisitions. CAC scores were determined by Agatston's method, and divided dichotomously (0, >0), and into risk categories (0, 1-99, 100-399, ≥400). We investigated the influence of heart rate and body mass index (BMI) on risk reclassification.

RESULTS

Positive CAC scores on cardiac CT ranged from 1 to 6926 (median 39). Compared to cardiac CT, chest CT had sensitivity of 0.96 (95%CI 0.94-0.98) and specificity of 0.99 (95%CI 0.97-0.99) for CAC detection (κ = 0.95). In participants with coronary calcification on cardiac CT, CAC score on chest CT was lower than on cardiac CT (median 30 versus 40, p˂0.001). Agreement in CAC-based risk strata was excellent (weighted κ = 0.95). Sixty-five cases (6.5%) were reclassified by one risk category in chest CT, with fifty-five (84.6%) shifting downward. Higher BMI resulted in higher reclassification rate (13% for BMI ≥30 versus 5.2% for BMI <30, p = 0.001), but there was no effect of heart rate.

CONCLUSION

Low-dose, high-pitch chest CT, using third-generation dual-source technology shows almost perfect agreement with cardiac CT in CAC detection and risk stratification. However, low-dose chest CT mainly underestimates the CAC score as compared to cardiac CT, and results in inaccurate risk categorization in BMI ≥30.

Natural course of coronary artery calcium progression in Asian population with an initial score of zero

Background

We aimed to investigate the natural course of coronary artery calcium progression in an Asian population with a baseline coronary artery calcium (CAC) score of zero, and to determine subclinical coronary atherosclerosis.

Methods

Four hundred fifty-nine subjects with at least two CAC scans with an initial score of zero were included. CAC progression (+) was defined by the development of any CAC (i.e., CAC > 0) during subsequent CT scans. Clinical characteristics and Framingham risk profiles were also recorded.

Results

Among 459 subjects, 106 (23.09%) experienced CAC progression during the average follow-up period of 5.71 ± 2.68 years. Older age, male gender, HDL-C, total cholesterol and higher Framingham risk score were independently associated with CAC progression. Framingham risk score had the better discriminative ability (AUC = 0.660) to predict CAC progression compared to the other parameters with a sensitivity of 75.24% and specificity of 53.95%. For the double zero score with coronary artery atherosclerosis prediction, older age, triglycerides, hypertension, and Framingham risk score were significantly associated with these events. Among these parameters, Framingham risk score may be a relatively acceptable parameter with high negative predictive (NPV = 96.4%) value to rule out double zero score with obstructive coronary artery atherosclerosis scenario with an optimum cut-off value of <16.9 (AUC =0.652, sensitivity of 57.69%; specificity of 68.82%).

Conclusions

A baseline zero CAC score in asymptomatic Chinese population with low to intermediate risk have a low incidence for CAC progression within the 5-years period. For CAC progression prediction, Framingham risk score with the cutoff < 11.1 may help confirm subjects at low risk to improve cardiovascular risk stratification and reclassification in the field of preventive cardiology.

Coronary Artery Calcium for Personalized Allocation of Aspirin in Primary Prevention of Cardiovascular Disease in 2019: The MESA Study (Multi-Ethnic Study of Atherosclerosis)

BACKGROUND

Recent American College of Cardiology/American Heart Association Primary Prevention Guidelines recommended considering low-dose aspirin therapy only among adults 40 to 70 years of age who are at higher atherosclerotic cardiovascular disease (ASCVD) risk but not at high risk of bleeding. However, it remains unclear how these patients are best identified. The present study aimed to assess the value of coronary artery calcium (CAC) for guiding aspirin allocation for primary prevention by using 2019 aspirin meta-analysis data on cardiovascular disease relative risk reduction and bleeding risk.

METHODS

The study included 6470 participants from the MESA Study (Multi-Ethnic Study of Atherosclerosis). ASCVD risk was estimated using the pooled cohort equations, and 3 strata were defined: <5%, 5% to 20%, and >20%. All participants underwent CAC scoring at baseline, and CAC scores were stratified as =0, 1 to 99, ≥100, and ≥400. A 12% relative risk reduction in cardiovascular disease events was used for the 5-year number needed to treat (NNT₅) calculations, and a 42% relative risk increase in major bleeding events was used for the 5-year number needed to harm (NNH₅) estimations.

RESULTS

Only 5% of MESA participants would qualify for aspirin consideration for primary prevention according to the American College of Cardiology/American Heart Association guidelines and using >20% estimated ASCVD risk to define higher risk. Benefit/harm calculations were restricted to aspirin-naive participants <70 years of age not at high risk of bleeding (n=3540). The overall NNT₅ with aspirin to prevent 1 cardiovascular disease event was 476 and the NNH₅ was 355. The NNT₅ was also greater than or similar to the NNH₅ among estimated ASCVD risk strata. Conversely, CAC≥100 and CAC≥400 identified subgroups in which NNT₅ was lower than NNH₅. This was true both overall (for CAC≥100, NNT₅=140 versus NNH₅=518) and within ASCVD risk strata. Also, CAC=0 identified subgroups in which the NNT₅ was much higher than the NNH₅ (overall, NNT₅=1190 versus NNH₅=567).

CONCLUSIONS

CAC may be superior to the pooled cohort equations to inform the allocation of aspirin in primary prevention. Implementation of current 2019 American College of Cardiology/American Heart Association guideline recommendations together with the use of CAC for further risk assessment may result in a more personalized, safer allocation of aspirin in primary prevention. Confirmation of these findings in experimental settings is needed.

Noninvasive Imaging to Assess Atherosclerotic Plaque Composition and Disease Activity: Coronary and Carotid Applications

Cardiovascular disease is one of the leading causes of mortality and morbidity worldwide. Atherosclerosis imaging has traditionally focused on detection of obstructive luminal stenoses or measurements of plaque burden. However, with advances in imaging technology it has now become possible to noninvasively interrogate plaque composition and disease activity, thereby differentiating stable from unstable patterns of disease and potentially improving risk stratification. This manuscript reviews multimodality imaging in this field, focusing on carotid and coronary atherosclerosis and how these novel techniques have the potential to complement current imaging assessments and improve clinical decision making.

Exposure to dietary polychlorinated biphenyls and dioxins, and its relationship with subclinical coronary atherosclerosis: The Aragon Workers' Health Study

BACKGROUND

Experimental evidence has revealed that exposure to polychlorinated biphenyls (PCBs) and dioxins directly impairs endothelial function and induces atherosclerosis progression. In the general population, despite a small number of recent studies finding a link between PCBs, and stroke and myocardial infraction, the association with early coronary atherosclerosis has not been examined yet.

OBJECTIVE

To examine whether dietary exposure to PCBs and dioxins is associated with subclinical coronary atherosclerosis in a middle-aged men.

DESIGN

Cross-sectional analysis comprising 1844 men in their 50 s and free of cardiovascular disease, who participated in the Aragon Workers' Health Study (AWHS). Individual dietary exposures to PCBs and dioxins were estimated by the contaminant's concentration in food coupled with the corresponding consumption and then participants were classified into quartiles of consumption. Coronary artery calcium score (CACS) was assessed by computerized tomography. We conducted ordered logistic regressions to estimate the odds ratio (OR) and 95% confidence intervals (CIs) for progression to the categories of more coronary artery calcium, adjusting for potential confounders.

RESULTS

Among the participants, coronary calcium was not shown in 60.1% (n = 1108), 29.8% had a CACS > 0 and <100 (n = 550), and the remaining 10.1% (n = 186) had a CACS ≥ 100. Compared with those in the first quartile of PCBs exposure, those in the fourth one had an increased odds for having coronary calcium (OR 2.02, 95% CI [1.18, 3.47], p trend 0.019) and for having progressed to categories of more intense calcification (OR 2.03, 95% CI [1.21, 3.40], p trend 0.012). However, no association was found between dietary dioxins exposure and prevalent coronary artery calcium.

CONCLUSIONS

In this general male population, dietary exposure to PCBs, but not to dioxins, was associated with a higher prevalence of coronary calcium and to more intense subclinical coronary atherosclerosis. PCBs exposure seems to increase the risk of coronary disease in men from the very early stages.

Radiomics of Coronary Artery Calcium in the Framingham Heart Study

PURPOSE

To extract radiomic features from coronary artery calcium (CAC) on CT images and to determine whether this approach could improve the ability to identify individuals at risk for a composite endpoint of clinical events.

MATERIALS AND METHODS

Participants from the Offspring and Third Generation cohorts of the community-based Framingham Heart Study underwent noncontrast cardiac CT (2002-2005) and were followed for more than a median of 9.1 years for composite major events. A total of 624 participants with CAC Agatston score (AS) of greater than 0 and good or excellent CT image quality were included for manual CAC segmentation and extraction of a predefined set of radiomic features reflecting intensity, shape, and texture. In a discovery cohort (n = 318), machine learning was used to select the 20 most informative and nonredundant CAC radiomic features, classify features predicting events, and define a radiomic-based score (RS). Performance of the RS was tested independently for the prediction of events in a validation cohort (n = 306).

RESULTS

The RS had a median value of 0.08 (interquartile range, 0.007-0.71) and a weak and modest correlation with Framingham risk score (FRS) (r = 0.2) and AS (r = 0.39), respectively. The continuous RS unadjusted, adjusted for age and sex, FRS, AS, and FRS plus AS were significantly associated with events (hazard ratio [HR] = 2.2, P < .001; HR = 1.8, P = .002; HR = 2.0, P < .001; HR = 1.7, P = .02; and HR = 1.8, P = .01, respectively). In participants with AS of less than 300, RS association with events remained significant when unadjusted and adjusted for age and sex, FRS, AS, and FRS plus AS (HR = 2.4, 2.8, 2.8, 2.3, and 2.6; P < .001, respectively). In the same subgroup of participants, adding the RS to AS resulted in a significant improvement in the discriminatory ability for events as compared with the AS (area under the receiver operating curve: 0.80 vs 0.68, respectively; P = .03).

CONCLUSION

A radiomic-based score, including the complex properties of CAC, may constitute an imaging biomarker to be further developed to identify individuals at risk for major adverse cardiovascular events in a community-based cohort. Supplemental material is available for this article. © RSNA, 2020.

18Fluoride-based molecular imaging of coronary atherosclerosis in HIV infected patients

BACKGROUND AND AIMS

Molecular imaging with ¹⁸Fluorodeoxyglucose (FDG) and ¹⁸F-sodium-fluoride (NaF) captures arterial inflammation and micro-calcification and can reveal potentially unstable atherosclerotic plaques.

METHODS

We performed FDG and NaF PET/CT imaging in two clinically similar cohorts of patients living with HIV (PLWH) with no symptomatic cardiovascular disease. The prevalence and intensity of coronary artery uptake of each tracer, measured as target-to-background ratio (TBR), were assessed in patients at low and high cardiovascular risk.

RESULTS

Ninety-three PLWH were submitted to PET/CT imaging with FDG (N = 43) and NaF (N = 50); 42% were at low and 58% at high cardiovascular risk. The intensity of uptake and multivessel coronary artery uptake were significantly higher with NaF than FDG both in low and high-risk patients. When each ¹⁸F-tracer was tested in low and high-risk patients, an equal proportion of subjects showed no vessel, single and multivessel NaF uptake; the same was true for no and single vessel uptake of FDG (no multivessel FDG uptake was noted). Waist circumference, CRP, D-dimer, HIV duration and treatment with nucleoside reverse transcriptase inhibitors were associated with high NaF uptake in univariable analyses; D-dimer remained significant in multivariable analyses (OR = 1.05; p=0.02). There were no significant associations with FDG uptake.

CONCLUSIONS

The prevalence of coronary artery uptake was higher with NaF compared to FDG both in high and low risk patients, hence microcalcification imaging may be a more sensitive tool to detect coronary atherosclerosis than inflammation imaging. However, the uptake of each ¹⁸Fluoride tracer was similar between low and high-risk subjects, and this underscores the discordance between clinical and imaging based risk assessment. Future investigation should address the prognostic significance of NaF coronary artery uptake.

Sex Differences in Coronary Artery Calcium and Long-term CV Mortality

PURPOSE OF REVIEW

To summarize differences in plaque depositions, coronary artery calcium (CAC) scoring, and the role of CAC in predicting atherosclerotic cardiovascular disease (ASCVD) mortality in men and women.

RECENT FINDINGS

Women have coronary plaque that is more lipid-rich, dense, and less calcified than their male counterparts. CAC scoring has emerged as a useful tool to quantify ASCVD burden. However, recent evidence favors the use of sex-adjusted CAC cutoffs for women to account for the relatively lower overall CAC burden and therefore risk stratify women appropriately. Several studies have identified CAC distribution patterns in women associated with increased CV mortality, particularly the number of lesions involved, CAC volume, and size. Multiple studies have shown that the pathophysiology and associated risks of ASCVD are different in women when compared with men. CAC scoring is a tool that is widely being used for ASCVD risk stratification. Recent studies have shown that although men have higher CAC burdens, women are more likely to develop plaque erosions with non-calcified plaque that carries a greater risk for cardiovascular events. Providers should be aware of sex-specific CAC patterns carrying increased mortality risk for women, particularly increasing lesion size and number. Given the differences in plaque composition and distribution, revised sex-adjusted CAC scoring is suggested to better risk stratify patients, especially those deemed intermediate risk, and decrease CV mortality.

Coronary atherosclerosis in middle-aged athletes: Current insights, burning questions, and future perspectives

Regular exercise training is considered healthy as it reduces the risk of cardiovascular events and mortality. Nevertheless, athletes are not immune to the development of cardiovascular diseases and recent studies reported a higher prevalence of coronary artery calcifications and atherosclerotic plaques in athletes compared to less active controls. These observations have raised many questions among sport scientists, sports cardiologists, amateur athletes, and the general population. For example, Are athletes (not) immune for coronary atherosclerosis? How to assess coronary atherosclerosis in athletes? What about chalk (calcified plaque) and cheese (mixed plaque)? Does exercise intensity play a role? Are there sport‐related differences? Are there sex differences? Can sports medical evaluation detect coronary atherosclerosis? Do athletes get worried? Should athletes get worried? How should athletes with coronary atherosclerosis be managed? The goal of this review is to discuss the latest scientific insights and to answer these important questions. Furthermore, we will explore potential clinical implications and point out directions for further research.

Detecting unstable plaques in humans using cardiac CT: Can it guide treatments?

Advances in imaging technology have driven the rapid expansion in the use of CT in the assessment of coronary atherosclerotic plaque. Based on a rapidly growing evidence base, current guidelines recommend coronary CT angiography as the first-line diagnostic test for patients presenting with stable chest pain. There is a growing need to refine current methods for diagnosis and risk stratification to improve the individualisation of preventative therapies. Imaging assessments of high-risk plaque with CT can be used to differentiate stable from unstable patterns of coronary atherosclerosis and potentially to improve patient risk stratification. This review will focus on coronary imaging with CT with a specific focus on the detection of coronary atherosclerosis, high-risk plaque features, and the implications for patient management.

Latest Advances in Cardiac CT

Recent rapid technological advancements in cardiac CT have improved image quality and reduced radiation exposure to patients. Furthermore, key insights from large cohort trials have helped delineate cardiovascular disease risk as a function of overall coronary plaque burden and the morphological appearance of individual plaques. The advent of CT-derived fractional flow reserve promises to establish an anatomical and functional test within one modality. Recent data examining the short-term impact of CT-derived fractional flow reserve on downstream care and clinical outcomes have been published. In addition, machine learning is a concept that is being increasingly applied to diagnostic medicine. Over the coming decade, machine learning will begin to be integrated into cardiac CT, and will potentially make a tangible difference to how this modality evolves. The authors have performed an extensive literature review and comprehensive analysis of the recent advances in cardiac CT. They review how recent advances currently impact on clinical care and potential future directions for this imaging modality.

Quantitative Clinical Nuclear Cardiology, Part 1: Established Applications

Single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) has attained widespread clinical acceptance as a standard of care for patients with known or suspected coronary artery disease (CAD). A significant contribution to this success has been the use of computer techniques to provide objective quantitative assessment in the standardization of the interpretation of these studies. Software platforms have been developed as a pipeline to provide the quantitative algorithms researched, developed and validated to be clinically useful so diagnosticians everywhere can benefit from these tools. The goal of this CME article (PART 1) is to describe the many quantitative tools that are clinically established and more importantly how clinicians should use them routinely in the interpretation, clinical management and therapy guidance of patients with CAD.