Visual Coronary and Aortic Calcium Scoring on Chest Computed Tomography Predict Mortality in Patients With Low-Density Lipoprotein-Cholesterol ≥190 mg/dL

Cardiovascular Risk Estimation and Stratification Among Individuals with Hypercholesterolemia

PURPOSE OF THE REVIEW

This review aims to assess the variability in considering hypercholesterolemia for cardiovascular risk stratification in the general population. Recent literature on the integration of hypercholesterolemia into clinical risk scores and its interaction with other risk factors will be explored.

RECENT FINDINGS

The impact of hypercholesterolemia on risk estimation varies among different cardiovascular risk calculators. Elevated lipid levels during early life stages contribute to atherosclerotic plaque development, influencing disease severity despite later treatment initiation. The interplay between low-density lipoprotein cholesterol (LDLc), inflammatory markers and non-LDL lipid parameters enhances cardiovascular risk stratification. Studies have also examined the role of coronary artery calcium (CAC) score as a negative risk marker in populations with severe hypercholesterolemia. Furthermore, polygenic risk scores (PRS) may aid in diagnosing non-monogenic hypercholesterolemia, refining cardiovascular risk stratification and guiding lipid-lowering therapy strategies. Understanding the heterogeneity in risk estimation and the role of emerging biomarkers and imaging techniques is crucial for optimizing cardiovascular risk prediction and guiding personalized treatment strategies in individuals with hypercholesterolemia.

Prevalence and clinical implications of coronary artery calcium scoring on non-gated thoracic computed tomography: a systematic review and meta-analysis

OBJECTIVES

Coronary artery calcifications (CACs) indicate the presence of coronary artery disease. CAC can be found on thoracic computed tomography (CT) conducted for non-cardiac reasons. This systematic review and meta-analysis of non-gated thoracic CT aims to assess the clinical impact and prevalence of CAC.

METHODS

Online databases were searched for articles assessing prevalence, demographic characteristics, accuracy and prognosis of incidental CAC on non-gated thoracic CT. Meta-analysis was performed using a random effects model.

RESULTS

A total of 108 studies (113,406 patients) were included (38% female). Prevalence of CAC ranged from 2.7 to 100% (pooled prevalence 52%, 95% confidence interval [CI] 46-58%). Patients with CAC were older (pooled standardised mean difference 0.88, 95% CI 0.65-1.11, p < 0.001), and more likely to be male (pooled odds ratio [OR] 1.95, 95% CI 1.55-2.45, p < 0.001), with diabetes (pooled OR 2.63, 95% CI 1.95-3.54, p < 0.001), hypercholesterolaemia (pooled OR 2.28, 95% CI 1.33-3.93, p < 0.01) and hypertension (pooled OR 3.89, 95% CI 2.26-6.70, p < 0.001), but not higher body mass index or smoking. Non-gated CT assessment of CAC had excellent agreement with electrocardiogram-gated CT (pooled correlation coefficient 0.96, 95% CI 0.92-0.98, p < 0.001). In 51,582 patients, followed-up for 51.6 ± 27.4 months, patients with CAC had increased all cause mortality (pooled relative risk [RR] 2.13, 95% CI 1.57-2.90, p = 0.004) and major adverse cardiovascular events (pooled RR 2.91, 95% CI 2.26-3.93, p < 0.001). When CAC was present on CT, it was reported in between 18.6% and 93% of reports.

CONCLUSION

CAC is a common, but underreported, finding on non-gated CT with important prognostic implications.

CLINICAL RELEVANCE STATEMENT

Coronary artery calcium is an important prognostic indicator of cardiovascular disease. It can be assessed on non-gated thoracic CT and is a commonly underreported finding. This represents a significant population where there is a potential missed opportunity for lifestyle modification recommendations and preventative therapies. This study aims to highlight the importance of reporting incidental coronary artery calcium on non-gated thoracic CT.

KEY POINTS

• Coronary artery calcification is a common finding on non-gated thoracic CT and can be reliably identified compared to gated-CT. • Coronary artery calcification on thoracic CT is associated with an increased risk of all cause mortality and major adverse cardiovascsular events. • Coronary artery calcification is frequently not reported on non-gated thoracic CT.

Opportunistic Screening for Coronary Artery Disease: An Untapped Population Health Resource

BACKGROUND

Coronary artery disease is the leading cause of death in the United States. At-risk asymptomatic adults are eligible for screening with electrocardiogram-gated coronary artery calcium (CAC) CT, which aids in risk stratification and management decision-making. Incidental CAC (iCAC) is easily quantified on chest CT in patients imaged for noncardiac indications; however, radiologists do not routinely report the finding.

OBJECTIVE

To determine the clinical significance of CAC identified incidentally on routine chest CT performed for noncardiac indications.

DESIGN

An informationist developed search strategies in MEDLINE, Embase, and SCOPUS, and two reviewers independently screened results at both the abstract and full text levels. Data extracted from eligible articles included age, rate of iCAC identification, radiologist reporting frequency, impact on downstream medical management, and association of iCAC with patient outcomes.

RESULTS

From 359 unique citations, 83 research publications met inclusion criteria. The percentage of patients with iCAC ranged from 9% to 100%. Thirty-one investigations measured association(s) between iCAC and cardiovascular morbidity and mortality, and 29 identified significant correlations, including nonfatal myocardial infarction, fatal myocardial infarction, major adverse cardiovascular event, cardiovascular death, and all-cause death. iCAC was present in 20% to 100% of the patients in these cohorts, but when present, iCAC was reported by radiologists in only 31% to 44% of cases. Between 18% and 77% of patients with iCAC were not on preventive medications in studies that reported these data. Seven studies measured the effect of reporting on guideline directed medical therapy, and 5 (71%) reported an increase in medication prescriptions after diagnosis of iCAC, with one confirming reductions in low-density lipoprotein levels. Twelve investigations reported good concordance between CAC grade on noncardiac CT and Agatston score on electrocardiogram-gated cardiac CT, and 10 demonstrated that artificial intelligence tools can reliably calculate an Agatston score on noncardiac CT.

CONCLUSION

A body of evidence demonstrates that patients with iCAC on routine chest CT are at risk for cardiovascular disease events and death, but they are often undiagnosed. Uniform reporting of iCAC in the chest CT impression represents an opportunity for radiology to contribute to early identification of high-risk individuals and potentially reduce morbidity and mortality. AI tools have been validated to calculate Agatston score on routine chest CT and hold the best potential for facilitating broad adoption.

Subclinical Atherosclerosis to Guide Treatment in Dyslipidemia and Diabetes Mellitus

PURPOSE OF REVIEW

Dyslipidemia and type 2 diabetes mellitus are two common conditions that are associated with an increased risk of atherosclerotic cardiovascular disease (ASCVD). In this review, we aimed to provide an in-depth and contemporary review of non-invasive approaches to assess subclinical atherosclerotic burden, predict cardiovascular risk, and guide appropriate treatment strategies. We focused this paper on two main imaging modalities: coronary artery calcium (CAC) score and computed tomography coronary angiography.

RECENT FINDINGS

Recent longitudinal studies have provided stronger evidence on the relationship between increased CAC, thoracic aorta calcification, and risk of cardiovascular events among those with primary hypercholesterolemia, highlighting the beneficial role of statin therapy. Interestingly, resilient profiles of individuals not exhibiting atherosclerosis despite dyslipidemia have been described. Non-conventional markers of dyslipidemia have also been associated with increased subclinical atherosclerosis presence and burden, highlighting the contribution of apolipoprotein B-100 (apoB)-rich lipoprotein particles, such as remnant cholesterol and lipoprotein(a), to the residual risk of individuals on-target for low-density lipoprotein cholesterol (LDL-C) goals. Regarding type 2 diabetes mellitus, variability in atherosclerotic burden has also been found, and CAC testing has shown significant predictive value in stratifying cardiovascular risk. Non-invasive assessment of subclinical atherosclerosis can help reveal the continuum of ASCVD risk in those with dyslipidemia and diabetes mellitus and can inform personalized strategies for cardiovascular disease prevention in the primary prevention setting.

Vascular Calcification Heterogeneity from Bench to Bedside: Implications for Manifestations, Pathogenesis, and Treatment Considerations

Vascular calcification (VC) is the ectopic deposition of calcium-containing apatite within vascular walls, exhibiting a high prevalence in older adults, and those with diabetes or chronic kidney disease. VC is a subclinical cardiovascular risk trait that increases mortality and functional deterioration. However, effective treatments for VC remain largely unavailable despite multiple attempts. Part of this therapeutic nihilism results from the failure to appreciate the diversity of VC as a pathological complex, with unforeseeable variations in morphology, risk associates, and anatomical and molecular pathogenesis, affecting clinical management strategies. VC should not be considered a homogeneous pathology because accumulating evidence refutes its conceptual and content uniformity. Here, we summarize the pathophysiological sources of VC heterogeneity from the intersecting pathways and networks of cellular, subcellular, and molecular crosstalk. Part of these pathological connections are synergistic or mutually antagonistic. We then introduce clinical implications related to the VC heterogeneity concept. Even within the same individual, a specific artery may exhibit the strongest tendency for calcification compared with other arteries. The prognostic value of VC may only be detectable with a detailed characterization of calcification morphology and features. VC heterogeneity is also evident, as VC risk factors vary between different arterial segments and layers. Therefore, diagnostic and screening strategies for VC may be improved based on VC heterogeneity, including the use of radiomics. Finally, pursuing a homogeneous treatment strategy is discouraged and we suggest a more rational approach by diversifying the treatment spectrum. This may greatly benefit subsequent efforts to identify effective VC therapeutics.

Association of cardiometabolic and vascular atherosclerosis phenotypes on non-contrast chest CT with incident heart failure in patients with severe hypercholesterolemia

BACKGROUND

Coronary artery calcium (CAC), thoracic aorta calcification (TAC), non-alcoholic fatty liver disease (NAFLD), and epicardial adipose tissue (EAT) are associated with atherosclerotic cardiovascular disease (ASCVD) and heart failure (HF).

OBJECTIVES

We aimed to determine whether these cardiometabolic and atherosclerotic risk factors identified by non-contrast chest computed tomography (CT) are associated with HF hospitalizations in patients with LDL-C≥ 190 mg/dL.

METHODS

We conducted a retrospective cohort analysis of patients with LDL-C ≥190 mg/dL, aged ≥40 years without established ASCVD or HF, who had a non-contrast chest CT within 3 years of LDL-C measurement. Ordinal CAC, ordinal TAC, EAT, and NAFLD were measured. Kaplan-Meier curves and multivariable Cox regression models were built to ascertain the association with HF hospitalization.

RESULTS

We included 762 patients with median age 60 (53-68) years, 68% (n=520) female, and median LDL-C level of 203 (194-216) mg/dL. Patients were followed for 4.7 (interquartile range 2.75-6.16) years, and 107 (14%) had a HF hospitalization. Overall, 355 (47%) patients had CAC=0, 210 (28%) had TAC=0, 116 (15%) had NAFLD, and median EAT was 79 mL (49-114). Moderate-Severe CAC (log-rank p<0.001) and TAC (log-rank p=0.006) groups were associated with increased HF hospitalizations. This association persisted when considering myocardial infarction (MI) as a competing risk. NAFLD and EAT volume were not associated with HF.

CONCLUSIONS

In patients without established ASCVD and LDL-C≥190 mg/dL, CAC was independently associated with increased HF hospitalizations while TAC, NAFLD, and EAT were not.

Long-Term Mortality in Patients With Severe Hypercholesterolemia Phenotype From a Racial and Ethnically Diverse US Cohort

BACKGROUND

Tools for mortality prediction in patients with the severe hypercholesterolemia phenotype (low-density lipoprotein cholesterol ≥190 mg/dL) are limited and restricted to specific racial and ethnic cohorts. We sought to evaluate the predictors of long-term mortality in a large racially and ethnically diverse US patient cohort with low-density lipoprotein cholesterol ≥190 mg/dL.

METHODS

We conducted a retrospective analysis of all patients with a low-density lipoprotein cholesterol ≥190 mg/dL seeking care at Montefiore from 2010 through 2020. Patients <18 years of age or with previous malignancy were excluded. The primary end point was all-cause mortality. Analyses were stratified by age, sex, and race and ethnicity. Patients were stratified by primary and secondary prevention. Cox regression analyses were used to adjust for demographic, clinical, and treatment variables.

RESULTS

A total of 18 740 patients were included (37% non-Hispanic Black, 30% Hispanic, 12% non-Hispanic White, and 2% non-Hispanic Asian patients). The mean age was 53.9 years, and median follow-up was 5.2 years. Both high-density lipoprotein cholesterol and body mass index extremes were associated with higher mortality in univariate analyses. In adjusted models, higher low-density lipoprotein cholesterol and triglyceride levels were associated with an increased 9-year mortality risk (adjusted hazard ratio [HR], 1.08 [95% CI, 1.05-1.11] and 1.04 [95% CI, 1.02-1.06] per 20-mg/dL increase, respectively). Clinical factors associated with higher mortality included male sex (adjusted HR, 1.31 [95% CI, 1.08-1.58]), older age (adjusted HR, 1.19 per 5-year increase [95% CI, 1.15-1.23]), hypertension (adjusted HR, 2.01 [95% CI, 1.57-2.57]), chronic kidney disease (adjusted HR, 1.68 [95% CI, 1.36-2.09]), diabetes (adjusted HR, 1.79 [95% CI, 1.50-2.15]), heart failure (adjusted HR, 1.51 [95% CI, 1.16-1.95]), myocardial infarction (adjusted HR, 1.41 [95% CI, 1.05-1.90]), and body mass index <20 kg/m2 (adjusted HR, 3.36 [95% CI, 2.29-4.93]). A significant survival benefit was conferred by lipid-lowering therapy (adjusted HR, 0.57 [95% CI, 0.42-0.77]). In the primary prevention group, high-density lipoprotein cholesterol <40 mg/dL was independently associated with higher mortality (adjusted HR, 1.49 [95% CI, 1.06-2.09]). Temporal trend analyses showed a reduction in statin use over time (P<0.001). In the most recent time period (2019-2020), 56% of patients on primary prevention and 85% of those on secondary prevention were on statin therapy.

CONCLUSIONS

In a large, diverse cohort of US patients with the severe hypercholesterolemia phenotype, we identified several patient characteristics associated with increased 9-year all-cause mortality and observed a decrease in statin use over time, in particular for primary prevention. Our results support efforts geared toward early recognition and consistent treatment for patients with severe hypercholesterolemia.

Association of Segment-Specific Pulse Wave Velocity With Vascular Calcification: The ARIC (Atherosclerosis Risk in Communities) Study

BACKGROUND

Pulse wave velocity (PWV) is a noninvasive measure of arterial stiffness and predictor of cardiovascular disease. However, the association between PWV and vascular calcification across different vascular beds has not been fully investigated. This study aimed to quantify the association between PWV and multiterritory calcification and to explore whether PWV can identify individuals with vascular calcification beyond traditional risk factors.

METHODS AND RESULTS

Among 1351 older adults (mean age, 79.2 years [SD, 4.1]) from the ARIC (Atherosclerosis Risk in Communities) study, we measured segment-specific PWVs: heart-carotid, heart-femoral, carotid-femoral, heart-ankle, brachial-ankle, and femoral-ankle. Dependent variables were high calcium score (≥75th percentile of Agatston score) across different vascular beds: coronary arteries, aortic valve ring, aortic valve, mitral valve, ascending aorta, and descending aorta. Quartiles of carotid-femoral, heart-femoral, heart-ankle, and brachial-ankle PWV were significantly associated with coronary artery calcium (eg, adjusted odds ratio [OR] for the highest versus lowest quartile of carotid-femoral PWV, 1.84 [95% CI, 1.24-2.74]). Overall, PWVs were most strongly associated with descending aorta calcification, with significant results for carotid-femoral, heart-femoral, heart-ankle, and brachial-ankle PWV (eg, adjusted OR for the highest versus lowest quartile of carotid-femoral PWV, 3.99 [95% CI, 2.61-6.17]). In contrast, femoral-ankle PWV was inversely associated with descending aorta calcification. Some PWVs improved the discrimination of coronary artery calcium and descending aorta calcification beyond traditional risk factors.

CONCLUSIONS

The associations of PWV with vascular calcification varied substantially across segments, with descending aorta calcification most closely linked to PWVs. Our study suggests that some PWVs, especially carotid-femoral PWV, are helpful to identify individuals with coronary artery calcium and descending aorta calcification.

The emerging role of noncoding RNAs in the EGFR signaling pathway in lung cancer

Noncoding ribonucleic acids (ncRNAs) have surfaced as essential orchestrators within the intricate system of neoplastic biology. Specifically, the epidermal growth factor receptor (EGFR) signalling cascade shows a central role in the etiological underpinnings of pulmonary carcinoma. Pulmonary malignancy persists as a preeminent contributor to worldwide mortality attributable to malignant neoplasms, with non-small cell lung carcinoma (NSCLC) emerging as the most predominant histopathological subcategory. EGFR is a key driver of NSCLC, and its dysregulation is frequently associated with tumorigenesis, metastasis, and resistance to therapy. Over the past decade, researchers have unveiled a complex network of ncRNAs, encompassing microRNAs, long noncoding RNAs, and circular RNAs, which intricately regulate EGFR signalling. MicroRNAs, as versatile post-transcriptional regulators, have been shown to target various components of the EGFR pathway, influencing cancer cell proliferation, migration, and apoptosis. Additionally, ncRNAs have emerged as critical modulators of EGFR signalling, with their potential to act as scaffolds, decoys, or guides for EGFR-related proteins. Circular RNAs, a relatively recent addition to the ncRNA family, have also been implicated in EGFR signalling regulation. The clinical implications of ncRNAs in EGFR-driven lung cancer are substantial. These molecules exhibit diagnostic potential as robust biomarkers for early cancer detection and personalized treatment. Furthermore, their predictive value extends to predicting disease progression and therapeutic outcomes. Targeting ncRNAs in the EGFR pathway represents a novel therapeutic approach with promising results in preclinical and early clinical studies. This review explores the increasing evidence supporting the significant role of ncRNAs in modulating EGFR signalling in lung cancer, shedding light on their potential diagnostic, prognostic, and therapeutic implications.

Association of Coronary Artery Calcium Detected by Routine Ungated CT Imaging With Cardiovascular Outcomes

BACKGROUND

Coronary artery calcium (CAC) is a strong predictor of cardiovascular events across all racial and ethnic groups. CAC can be quantified on nonelectrocardiography (ECG)-gated computed tomography (CT) performed for other reasons, allowing for opportunistic screening for subclinical atherosclerosis.

OBJECTIVES

The authors investigated whether incidental CAC quantified on routine non-ECG-gated CTs using a deep-learning (DL) algorithm provided cardiovascular risk stratification beyond traditional risk prediction methods.

METHODS

Incidental CAC was quantified using a DL algorithm (DL-CAC) on non-ECG-gated chest CTs performed for routine care in all settings at a large academic medical center from 2014 to 2019. We measured the association between DL-CAC (0, 1-99, or ≥100) with all-cause death (primary outcome), and the secondary composite outcomes of death/myocardial infarction (MI)/stroke and death/MI/stroke/revascularization using Cox regression. We adjusted for age, sex, race, ethnicity, comorbidities, systolic blood pressure, lipid levels, smoking status, and antihypertensive use. Ten-year atherosclerotic cardiovascular disease risk was calculated using the pooled cohort equations.

RESULTS

Of 5,678 adults without ASCVD (51% women, 18% Asian, 13% Hispanic/Latinx), 52% had DL-CAC >0. Those with DL-CAC ≥100 had an average 10-year ASCVD risk of 24%; yet, only 26% were on statins. After adjustment, patients with DL-CAC ≥100 had increased risk of death (HR: 1.51; 95% CI: 1.28-1.79), death/MI/stroke (HR: 1.57; 95% CI: 1.33-1.84), and death/MI/stroke/revascularization (HR: 1.69; 95% CI: 1.45-1.98) compared with DL-CAC = 0.

CONCLUSIONS

Incidental CAC ≥100 was associated with an increased risk of all-cause death and adverse cardiovascular outcomes, beyond traditional risk factors. DL-CAC from routine non-ECG-gated CTs identifies patients at increased cardiovascular risk and holds promise as a tool for opportunistic screening to facilitate earlier intervention.

Evaluation of Lower Extremity Calcium Score as a Measure of Peripheral Arterial Disease Burden and Amputation Risk

BACKGROUND

The ankle-brachial pressure index (ABI) and toe-brachial pressure index (TBI) are commonly used diagnostic tools for peripheral artery disease (PAD) that are unreliable in the presence of calcified vessels. In this study, we aimed to demonstrate the utility of the lower extremity calcium score (LECS) in addition to ABI and TBI in measuring disease burden and predicting the risk of amputation in patients with PAD.

METHODS

Patients who were evaluated in the vascular surgery clinic at Emory University for PAD and who underwent noncontrast computed tomography of the aorta and lower extremities were included in the study. Aortoiliac, femoral-popliteal, and tibial calcium scores were measured using the Agatston method. ABI and TBI that were obtained within 6 months of the computed tomography scan were noted and divided into categories of PAD severity. Associations between ABI, TBI, and LECS of each anatomic segment were evaluated. Univariate and multivariate ordinal regression analyses were performed to predict the outcome of amputation. Receiver operating characteristic analysis was performed to compare LECS with other variables in its ability to predict amputation.

RESULTS

Fifty patients included in the study cohort were divided into LECS quartiles, with 12-13 patients in each quartile. The highest quartile tended to be older (P = 0.016), had a higher percentage of diabetics (P = 0.034), and had a higher frequency of major amputations (P = 0.004) compared to the other quartiles. Patients in the highest quartile of tibial calcium score were more likely to have stage 3 chronic kidney disease (CKD) or greater (P = 0.011) and also had a higher frequency of amputation (P < 0.005) and mortality (P = 0.041). We found no significant association between each anatomic LECS and ABI/TBI categories. On univariate analysis, CKD (Odds Ratio [OR] 12.92 (95% CI 2.01 to 82.83), P = 0.007), diabetes mellitus (OR 5.47 (95% CI 1.27 to 23.64), P = 0.023), tibial calcium score (OR 6.62 (95% CI 1.79 to 24.54), P = 0.005), and total bilateral calcium score (OR 6.32 (95% CI 1.18 to 33.78), P = 0.031) were associated with increased risk of amputation. On multivariate stepwise ordinal regression, TBI and tibial calcium score were identified as important predictors of amputation, with hyperlipidemia and CKD increasing the overall prediction of the model. On Receiver operating characteristic analysis, the addition of the tibial calcium score (area under the curve 0.94, standard error 0.048) significantly improved the prediction of amputation compared to hyperlipidemia, CKD, and TBI alone (area under the curve 0.82, standard error 0.071, P = 0.022).

CONCLUSIONS

The addition of tibial calcium score to other known PAD risk factors may improve the prediction of amputation in patients with PAD.

Imaging subclinical coronary atherosclerosis to guide lipid management, are we there yet?

Atherosclerotic cardiovascular disease risk (ASCVD) is an ongoing epidemic, and lipid abnormalities are its primordial cause. Most individuals suffering a first ASCVD event are previously asymptomatic and often do not receive preventative therapies. The cornerstone of primary prevention has been the identification of individuals at risk through risk calculators based on clinical and laboratory traditional risk factors plus risk enhancers. However, it is well accepted that a clinical risk calculator misclassifies a significant proportion of individuals leading to the prescription of a lipid-lowering medication with very little yield or a missed opportunity for lipid-lowering agents with a potentially preventable event. The development of coronary artery calcium scoring (CAC) and CT coronary angiography (CCTA) provide complementary tools to directly visualize coronary plaque and other risk-modifying imaging components that can potentially provide individualized lipid management. Understanding patient selection for CAC or potentially CCTA and the risk implications of the different parameters provided, such as CAC score, coronary stenosis, plaque characteristics and burden, epicardial adipose tissue, and pericoronary adipose tissue, have grown more complex as technologies evolve. These parameters directly affect the shared decision with patients to start or withhold lipid-lowering therapies, to adjust statin intensity or LDL cholesterol goals. Emerging lipid lowering studies with non-invasive imaging as a guide to patient selection and treatment efficacy, plus the evolution of lipid lowering therapies from statins to a diverse armament of newer high-cost agents have pushed these two fields forward with a complex interaction. This review will discuss existing risk estimators, and non-invasive imaging techniques for subclinical coronary atherosclerosis, traditionally studied using CAC and more recently CCTA with qualitative and quantitative measurements. We will also explore the current data, gaps of knowledge and future directions on the use of these techniques in the risk-stratification and guidance of lipid management.