Extracoronary Thoracic and Coronary Artery Calcifications on Chest CT for Lung Cancer Screening: Association with Established Cardiovascular Risk Factors - The "CT-Risk" Trial

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.

ERS/ESTS/ESTRO/ESR/ESTI/EFOMP statement on management of incidental findings from low dose CT screening for lung cancer

BACKGROUND

Screening for lung cancer with low radiation dose computed tomography has a strong evidence base, is being introduced in several European countries and is recommended as a new targeted cancer screening programme. The imperative now is to ensure that implementation follows an evidence-based process that will ensure clinical and cost effectiveness. This European Respiratory Society (ERS) task force was formed to provide an expert consensus for the management of incidental findings which can be adapted and followed during implementation.

METHODS

A multi-European society collaborative group was convened. 23 topics were identified, primarily from an ERS statement on lung cancer screening, and a systematic review of the literature was conducted according to ERS standards. Initial review of abstracts was completed and full text was provided to members of the group for each topic. Sections were edited and the final document approved by all members and the ERS Science Council.

RESULTS

Nine topics considered most important and frequent were reviewed as standalone topics (interstitial lung abnormalities, emphysema, bronchiectasis, consolidation, coronary calcification, aortic valve disease, mediastinal mass, mediastinal lymph nodes and thyroid abnormalities). Other topics considered of lower importance or infrequent were grouped into generic categories, suitable for general statements.

CONCLUSIONS

This European collaborative group has produced an incidental findings statement that can be followed during lung cancer screening. It will ensure that an evidence-based approach is used for reporting and managing incidental findings, which will mean that harms are minimised and any programme is as cost-effective as possible.

ERS/ESTS/ESTRO/ESR/ESTI/EFOMP statement on management of incidental findings from low dose CT screening for lung cancer

BACKGROUND

Screening for lung cancer with low radiation dose computed tomography has a strong evidence base, is being introduced in several European countries and is recommended as a new targeted cancer screening programme. The imperative now is to ensure that implementation follows an evidence-based process that will ensure clinical and cost effectiveness. This European Respiratory Society (ERS) task force was formed to provide an expert consensus for the management of incidental findings which can be adapted and followed during implementation.

METHODS

A multi-European society collaborative group was convened. 23 topics were identified, primarily from an ERS statement on lung cancer screening, and a systematic review of the literature was conducted according to ERS standards. Initial review of abstracts was completed and full text was provided to members of the group for each topic. Sections were edited and the final document approved by all members and the ERS Science Council.

RESULTS

Nine topics considered most important and frequent were reviewed as standalone topics (interstitial lung abnormalities, emphysema, bronchiectasis, consolidation, coronary calcification, aortic valve disease, mediastinal mass, mediastinal lymph nodes and thyroid abnormalities). Other topics considered of lower importance or infrequent were grouped into generic categories, suitable for general statements.

CONCLUSIONS

This European collaborative group has produced an incidental findings statement that can be followed during lung cancer screening. It will ensure that an evidence-based approach is used for reporting and managing incidental findings, which will mean that harms are minimised and any programme is as cost-effective as possible.

Prevalence of coronary calcification on preoperative computed tomography and its management in thoracic surgery

PURPOSE

We investigated the preoperative assessment of coronary artery calcification using computed tomography for appropriate intraoperative management to reduce the risk of perioperative cardiac complications during pulmonary resection.

METHODS

Patients (n = 665) who underwent anatomical lung resection were examined. The extent of preoperative asymptomatic coronary artery stenosis or cardiac complications in patients with coronary artery calcification was assessed. In addition, the risk factors for perioperative cardiac complications were determined.

RESULTS

Coronary artery calcification was detected in 233 (35.0%) asymptomatic patients. Nineteen (8.2%) patients with coronary artery calcification had coronary artery stenosis ≥ 75%. Percutaneous coronary intervention was performed preoperatively (n = 3) and postoperatively (n = 10), and preoperative drug intervention was performed in 10 cases. One case of severe postoperative cardiac complications and 20 cases of mild postoperative cardiac complications, including those without coronary artery calcification, occurred. Patients with calcified coronary arteries were at risk of cardiovascular complications in the perioperative period. However, patients with coronary artery calcification who underwent preoperative cardiology intervention had no significant perioperative cardiovascular complications.

CONCLUSIONS

Coronary artery calcification detected on preoperative computed tomography is a risk factor for perioperative cardiovascular complications. Early intervention may reduce the risk of such complications.

Factors predicting the occurrence of aortic valve calcification in patients with coronary artery calcification in China

OBJECTIVES

In patients with coronary artery calcification (CAC), a predictor of adverse cardiovascular events, coronary computed tomography angiography (CCTA) also shows valvular calcification. In this study, we evaluated common clinical indicators in CAC patients with aortic (AoVC) and mitral valve (MVC) calcification.

METHODS

CAC and valvular calcification were quantified using the Agatston score in 636 hospitalised patients with CAC who underwent CCTA.

RESULTS

Valvular calcification was found in 30.5% of patients, with 25.2% (160 patients) showing AoVC. Age was an independent predictor of AoVC in both men (odds ratio (OR), 1.086; 95% confidence interval (CI), [1.054-1.119]; p < 0.001) and women (OR, 1.109; CI, [1.066-1.154]; p < 0.001). In men, we also found that a history of cerebral infarction was an independent predictor of AoVC (OR, 2.402; CI, [1.177-4.902]; p < 0.05). The independent predictors of AoVC in the 60- to 69-years age group were BMI (OR, 1.181; CI, [1.061-1.316]; p < 0.01) and history of cerebral infarction (OR, 3.187; CI, [1.283-7.919]; p < 0.05).

CONCLUSIONS

Age is a key independent predictor of AoVC in CAC patients. History of cerebrovascular disease was also an independent predictor of AoVC, but only in men and patients aged 60-69 years. Our results indicate that a history of cerebral infarction may be used as a risk factor when identifying AoVC in patients with CAC.

Predictive Value of Coronary Artery Calcium in Patients Receiving Computed Tomography Pulmonary Angiography for Suspected Pulmonary Embolism in the Emergency Department

PURPOSE

Coronary artery calcium (CAC) is a frequent incidental finding on computed tomography pulmonary angiogram (CTPA) in the evaluation of pulmonary embolism (PE) in the emergency department (ED); however, its prognostic value is unclear. In this study, we interrogate the prognostic value of CAC identified on CTPA in predicting adverse outcomes in the evaluation of PE in the ED.

MATERIALS AND METHODS

In this retrospective cohort study, we identified 610 patients presenting to the ED in 2013 and evaluated with CTPA for suspected PE. Ordinal CAC scores were evaluated as absent (0), mild (1), moderate (2), or severe (3) in each of the 4 main coronary arteries. Composite CAC scores were subsequently compared against adverse clinical outcomes, defined as intensive care unit admission, hospital stay longer than 72 hours, or death during hospital course or at 6-month follow-up, using univariate and multivariate logistic regression analyses. Relevant exclusion criteria included a history of cardiovascular disease.

RESULTS

In all, 365 patients met the inclusion criteria (231 women, mean age 56±16 y) with 132 patients (36%) having some degree of CAC and 16 (4%) having severe CAC. Known malignancy was present in 151 (41%) patients and composite adverse clinical outcomes were observed in 98 patients (32%). Age, presence of acute PE, malignancy, and presence of CAC were significant predictors of adverse outcomes on both univariate and multivariate analyses. CAC was not an independent predictor of short-term adverse outcomes on multivariate analysis ( P =0.06) when all patients were considered. However, when patients with known malignancy were excluded, CAC was an independent predictor of short-term adverse outcomes (odds ratio=2.5, confidence interval=1.1-5.5, P =0.03) independent of age and presence of PE.

CONCLUSION

The presence of CAC on CT PA was predictive of adverse outcomes in patients without known cardiac disease presenting to the ED with suspected PE.

Associations of endogenous sex hormone levels with the prevalence and progression of valvular and thoracic aortic calcification in the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND AND AIMS

Sex hormones (SH) may contribute to sex differences in cardiovascular disease (CVD). High free testosterone (T) and low sex hormone binding globulin (SHBG) have been associated with progression of coronary artery calcification in women. We now examined the association of SH with extra-coronary calcification (ECC) prevalence and progression among MESA participants.

METHODS

We studied 2,737 postmenopausal women and 3,130 men free of clinical CVD with baseline SH levels. ECC measurements [ascending and descending thoracic aortic calcification (ATAC, DTAC), mitral annular calcification (MAC), aortic valve calcification (AVC)] were obtained by computed tomography at baseline and after 2.4 ± 0.9 years. We used multivariable Poisson regression to evaluate associations with ECC prevalence and incidence (Agatston scores >0) and linear mixed effects models for ECC progression, per 1-SD increment in log(SH) in women and men separately.

RESULTS

The mean age was 65 ± 9 and 62 ± 10 years for women and men, respectively. In women, greater free T and lower SHBG were associated with MAC incidence in a demographic-adjusted model only. In men, lower free T was associated with MAC prevalence, DTAC incidence and progression, while greater SHBG was associated with MAC prevalence and DTAC progression after further adjusting for CVD risk factors.

CONCLUSIONS

In this diverse cohort free of CVD, we found some associations of SH with ECC measures. In particular, free T was inversely associated with prevalent MAC and DTAC progression in men independent of CVD risk factors. SH may influence vascular calcification, but further work is needed to understand clinical implications of these findings.

Prediction of Coronary Calcification and Stenosis: Role of Radiomics From Low-Dose CT

RATIONALE AND OBJECTIVES

We aimed to assess relationship between single-click, whole heart radiomics from low-dose computed tomography (LDCT) for lung cancer screening with coronary artery calcification and stenosis.

MATERIALS AND METHODS

The institutional review board-approved, retrospective study included all 106 patients (68 men, 38 women, mean age 64 ± 7 years) who underwent both LDCT for lung cancer screening and had calcium scoring and coronary computed tomography angiography in our institution. We recorded the clinical variables including patients' demographics, smoking history, family history, and lipid profiles. Coronary calcium scores and grading of coronary stenosis were recorded from the radiology information system. We calculated the multiethnic scores for atherosclerosis risk scores to obtain 10-year coronary heart disease (MESA 10-Y CHD) risk of cardiovascular disease for all patients. Deidentified LDCT exams were exported to a Radiomics prototype for automatic heart segmentation, and derivation of radiomics. Data were analyzed using multiple logistic regression and kernel Fisher discriminant analyses.

RESULTS

Whole heart radiomics were better than the clinical variables for differentiating subjects with different Agatston scores (≤400 and >400) (area under the curve [AUC] 0.92 vs 0.69). Prediction of coronary stenosis and MESA 10-Y CHD risk was better on whole heart radiomics (AUC:0.86-0.87) than with clinical variables (AUC:0.69-0.79). Addition of clinical variables or visual assessment of coronary calcification from LDCT to whole heart radiomics resulted in a modest change in the AUC.

CONCLUSION

Single-click, whole heart radiomics obtained from LDCT for lung cancer screening can differentiate patients with different Agatston and MESA risk scores for cardiovascular diseases.

The radiologist's role in lung cancer screening

Lung cancer is still the deadliest cancer in men and women worldwide. This high mortality is related to diagnosis in advanced stages, when curative treatment is no longer an option. Large randomized controlled trials have shown that lung cancer screening (LCS) with low-dose computed tomography (CT) can detect lung cancers at earlier stages and reduce lung cancer-specific mortality. The recent publication of the significant reduction of cancer-related mortality by 26% in the Dutch-Belgian NELSON LCS trial has increased the likelihood that implementation of LCS in Europe will move forward. Radiologists are important stakeholders in numerous aspects of the LCS pathway. Their role goes beyond nodule detection and nodule management. Being part of a multidisciplinary team, radiologists are key players in numerous aspects of implementation of a high quality LCS program. In this non-systematic review we discuss the multifaceted role of radiologists in LCS.

Risk assessment of acute pulmonary embolism utilizing coronary artery calcifications in patients that have undergone CT pulmonary angiography and transthoracic echocardiography

OBJECTIVE

To evaluate the relation of coronary artery calcifications (CAC) on non-ECG-gated CT pulmonary angiography (CTPA) with short-term mortality in patients with acute pulmonary embolism (PE).

METHODS

We retrospectively included all in-patients between May 2007 and December 2014 with an ICD-9 code for acute PE and CTPA and transthoracic echocardiography available. CAC was qualitatively graded as absent, mild, moderate, or severe. Relations of CAC with overall and PE-related 30-day mortality were assessed using logistic regression analyses. The independence of those relations was assessed using a nested approach, first adjusting for age and gender, then for RV strain, peak troponin T, and cardiovascular risk factors for an overall model.

RESULTS

Four hundred seventy-nine patients were included (63 ± 16 years, 52.8% women, 47.2% men). In total, 253 (52.8%) had CAC-mild: 143 (29.9%); moderate: 89 (18.6%); severe: 21 (4.4%). Overall mortality was 8.8% (n = 42) with higher mortality with any CAC (12.6% vs. 4.4% without; odds ratio [OR] 3.1 [95%CI 2.1-14.5]; p = 0.002). Mortality with severe (19.0%; OR 5.1 [95%CI 1.4-17.9]; p = 0.011), moderate (11.2%; OR 2.7 [95%CI 1.1-6.8]; p = 0.031), and mild CAC (12.6%; OR 3.1 [95%CI 1.4-6.9]; p = 0.006) was higher than without. OR adjusted for age and gender was 2.7 (95%CI 1.0-7.1; p = 0.050) and 2.6 (95%CI 0.9-7.1; p = 0.069) for the overall model. PE-related mortality was 4.0% (n = 19) with higher mortality with any CAC (5.9% vs. 1.8% without; OR 3.5 [95%CI 1.1-10.7]; p = 0.028). PE-related mortality with severe CAC was 9.5% (OR 5.8 [95%CI 1.0-34.0]; p = 0.049), with moderate CAC 6.7% (OR 4.0 [95%CI 1.1-14.6]; p = 0.033), and with mild 4.9% (OR 2.9 [95%CI 0.8-9.9]; p = 0.099). OR adjusted for age and gender was 4.2 (95%CI 0.9-20.7; p = 0.074) and 3.4 (95%CI 0.7-17.4; p = 0.141) for the overall model. Patients with sub-massive PE showed similar results.

CONCLUSION

CAC is frequent in acute PE patients and associated with short-term mortality. Visual assessment of CAC may serve as an easy, readily available tool for early risk stratification in those patients.

KEY POINTS

• Coronary artery calcification assessed on computed tomography pulmonary angiography is frequent in patients with acute pulmonary embolism. • Coronary artery calcification assessed on computed tomography pulmonary angiography is associated with 30-day overall and PE-related mortality in patients with acute pulmonary embolism. • Coronary artery calcification assessed on computed tomography pulmonary angiography may serve as an additional, easy readily available tool for early risk stratification in those 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.

Coronary artery calcium data and reporting system: Strengths and limitations

Coronary artery calcium data and reporting system (CAC-DRS) is a recently introduced standardized reporting system for calcium scoring on computed tomography. CAC-DRS provides four risk categories (0, 1, 2 and 3) along with treatment recommendations for each category. As with any other new reporting platform, CAC-DRS has both advantages and disadvantages. Improved communication, better clarity of details, organized management recommendations and utility in future research and education are the major strengths of CAC-DRS. It has many limitations such as questionable need for a new system, few missing components, use of a less accurate visual method and treatment suggestions based on expert opinion instead of clinical trials. In this contemporary review, we discuss the new reporting system CAC-DRS, its application, strengths and limitations and conclude with some remarks for the future.

GlycA, a Novel Inflammatory Marker and Its Association With Peripheral Arterial Disease and Carotid Plaque: The Multi-Ethnic Study of Atherosclerosis

GlycA, a composite biomarker of systemic inflammation, is associated with cardiovascular disease (CVD) and mortality, but its relationship with peripheral artery disease (PAD) is unknown. We assessed whether plasma GlycA is associated with ankle-brachial index (ABI), carotid plaque (CP), and incident clinical PAD among 6466 Multi-Ethnic Study of Atherosclerosis participants without CVD at baseline. GlycA, ABI, and CP were measured at baseline. Both ABI and CP were remeasured at 10 years. Incident clinical PAD was ascertained from hospital records. We used logistic, Cox, and linear mixed regression models adjusted for demographic and lifestyle factors. Mean (standard deviation, SD) was 62 (10) years for age and 381 (61) µmol/L for GlycA; 53% were women. GlycA was associated with both prevalent low ABI ≤0.8 (prevalence odds ratio [95% confidence interval, CI] per SD increment in GlycA, 1.65 [1.39-1.97]) and CP (1.19 [1.11-1.27]) at baseline. There were no significant associations of GlycA with incident low ABI, incident CP, or 10-year change in ABI or CP score. We identified 110 incident cases of PAD after 79 590 person-years. The hazard ratio (95% CI) of incident PAD per SD increment in GlycA was 1.38 (1.14-1.66). In conclusion, GlycA was associated with prevalent low ABI, prevalent CP, and incident PAD after a median of 14 years.

The novel inflammatory marker GlycA and the prevalence and progression of valvular and thoracic aortic calcification: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND AND AIMS

GlycA is a novel composite biomarker of systemic inflammation reflecting posttranslational glycosylation of acute phase reactants. GlycA has been associated with coronary artery calcium, cardiovascular disease (CVD) events and mortality. Vascular calcifications outside of the coronary arteries are risk markers of CVD and mortality. Whether GlycA is linked to extra-coronary calcifications (ECC) is not well established.

METHODS

We studied 6462 MESA participants free of clinical CVD who had plasma GlycA measured at baseline. ECCs [calcification in aortic valve (AVC), mitral annulus (MAC), ascending and descending thoracic aorta (ATAC, DTAC)] were ascertained at baseline and follow-up visit (median 2.3-yrs later) by cardiac CT. Poisson regression models with robust variance estimation assessed associations of GlycA with prevalent and incident ECC. Linear mixed models assessed the cross-sectional and 2-year change in ECC. Models were adjusted for demographic and lifestyle factors.

RESULTS

In cross-sectional analysis, GlycA (per SD increment) was positively associated with prevalent AVC, ATAC and DTAC with adjusted prevalence ratios (95% CI) of 1.08 (1.01-1.14), 1.18 (1.03-1.34) and 1.10 (1.06-1.14), respectively. There was also a significant association between GlycA and baseline extent of both ATAC and DTAC. Longitudinally, GlycA was positively associated with incident MAC and DTAC, with adjusted incidence ratios of 1.18 (1.03-1.37) and 1.17 (1.07-1.28), respectively. GlycA was also associated with 2-year change in MAC and DTAC extent.

CONCLUSIONS

In this diverse cohort free from clinical CVD, we found GlycA was positively associated with prevalent and incident ECC measures, in particular for progression of MAC and DTAC.

Coronary artery calcification in lung cancer screening

Lung cancer screening has been shown in the National Lung Screening Trial (NLST) to result in a statistically significant decrease in lung cancer specific mortality. Also within that trial there was shown to be a 7% decrease in all-cause mortality. While the reasons for this benefit are not entirely clear, it may relate to the detection and treatment of other important findings. Smokers not only have a higher risk of lung cancer, but also increased risk of atherosclerosis. The latter can be detected by the discovery of aortic and/or coronary artery calcium on unenhanced CT. As coronary artery calcium scoring can be used as a screening tool to detect asymptomatic coronary artery atherosclerosis, its detection on lung cancer screening exams has the potential to provide both a teachable moment and treatment aimed at the reduction of major coronary artery events and mortality. In this review we will discuss the use of coronary artery calcium scoring for the detection of atherosclerotic disease and its potential application to lung cancer screening populations.

Reporting of coronary artery calcification on chest CT studies in breast cancer patients at high risk of cancer therapy related cardiac events

Background

The identification of coronary artery calcification (CAC) detected coincidentally on chest CT exams could assist in cardiovascular risk assessment but may not be reported consistently on clinical studies. Cardiovascular risk factor stratification is important to predict short term cardiac events during cancer therapy and long term cardiac event free survival in cancer patients. We sought to determine the prevalence of CAC and clinical reporting rates in a cohort of cancer patients at high risk of cancer therapy related cardiac events.

Methods

408 Breast cancer patients who were referred to a cardiac oncology clinic were screened. Inclusion criteria included having had a CT chest and the absence of known coronary disease. Among those screened 263 patients were included in the study.

Results

CAC was identified in 70 patients (26%). CAC was reported in 18% of studies. The reporting rates of CAC increased with the extent of coronary calcification (p < 0.01) and increased during the period of the study (p < 0.05).

Conclusions

CAC was commonly detected on chest CT studies in this observational study of breast cancer patients at high risk of cardiac oncology events. The presence of CAC was often not reported clinically but reporting rates have increased over time. Recent SCCT/STR guidelines recommend reporting the presence of CAC on routine chest CT scans in recognition of the importance of CAC as a predictor of cardiovascular events. Reporting of CAC on chest CTs may help to further risk stratify breast cancer patients and improve cardiovascular outcomes in this vulnerable population.

Density of calcium in the ascending thoracic aorta and risk of incident cardiovascular disease events

BACKGROUND AND AIMS

The volume and density of coronary artery calcium (CAC) both independently predict cardiovascular disease (CVD) beyond standard risk factors, with CAC density inversely associated with incident CVD after accounting for CAC volume. We tested the hypothesis that ascending thoracic aorta calcium (ATAC) volume and density predict incident CVD events independently of CAC.

METHODS

The Multi-Ethnic Study of Atherosclerosis (MESA) is a prospective cohort study of participants without clinical CVD at baseline. ATAC and CAC were measured from baseline cardiac computed tomography (CT). Cox regression models were used to estimate the associations of ATAC volume and density with incident coronary heart disease (CHD) events and CVD events, after adjustment for standard CVD risk factors and CAC volume and density.

RESULTS

Among 6811 participants, 234 (3.4%) had prevalent ATAC and 3395 (49.8%) had prevalent CAC. Over 10.3 years, 355 CHD and 562 CVD events occurred. One-standard deviation higher ATAC density was associated with a lower risk of CHD (HR 0.48 [95% CI 0.29-0.79], p<0.01) and CVD (HR 0.56 [0.37-0.84], p<0.01) after full adjustment. ATAC volume was not associated with outcomes after full adjustment.

CONCLUSIONS

ATAC was uncommon in a cohort free of clinical CVD at baseline. However, ATAC density was inversely associated with incident CHD and CVD after adjustment for CVD risk factors and CAC volume and density.

Use of the augmentation index from applanation tonometry of the radial artery for assessing the extent of coronary artery calcium as assessed by coronary computed tomography

BACKGROUND

The augmentation index (AI) obtained from applanation tonometry of the radial artery is technically the easiest and quickest of available methods for assessing arterial stiffness. We tested the hypothesis that the radial AI is associated with the extent of coronary artery calcium (CAC) as assessed by coronary computed tomography (CCT).

METHODS AND RESULTS

This study included 161 patients with known or suspected coronary artery disease undergoing central hemodynamic measurements and CCT. Radial AI was recorded and was corrected in accordance with heart rate (radial AI@75). Thirty-seven patients had no CAC (CAC score = 0), 85 had low-grade CAC (CAC score = 1-399), and 39 had high-grade CAC (CAC score ≥400). Coronary risk factors, except for age and serum creatinine, were similar among the three groups. There were significant differences in brachial systolic blood pressure (SBP) (p = 0.011) and radial AI@75 (%) (p = 0.006). Multivariate analysis showed that age (β = 0.27, p = 0.001), serum creatinine (β = 0.18, p = 0.03), and radial AI@75 (β = 0.24, p = 0.005) were significantly associated with ln (CAC score + 1), whereas brachial SBP was not. Additionally, serum creatinine (odds ratio: 11.91, 95% confidence interval: 1.46-112.0, p = 0.02) and radial AI@75 (per 10%) (odds ratio: 1.76, 95% confidence interval: 1.22-2.64, p = 0.002) were independent factors associated with high-grade CAC.

CONCLUSIONS

Our results suggest that the radial AI is better for estimating CAC than brachial SBP in patients with known or suspected coronary artery disease.

Estimation of cardiovascular risk on routine chest CT: Ordinal coronary artery calcium scoring as an accurate predictor of Agatston score ranges

BACKGROUND

Coronary artery calcium (CAC) is often identified on routine chest computed tomography (CT). The purpose of our study was to evaluate whether ordinal scoring of CAC on non-gated, routine chest CT is an accurate predictor of Agatston score ranges in a community-based population, and in particular to determine the accuracy of an ordinal score of zero on routine chest CT.

METHODS

Two thoracic radiologists reviewed consecutive same-day ECG-gated and routine non-gated chest CT scans of 222 individuals. CAC was quantified using the Agatston scoring on the ECG-gated scans, and using an ordinal method on routine scans, with a score from 0 to 12. The pattern and distribution of CAC was assessed. The correlation between routine exam ordinal scores and Agatston scores in ECG-gated exams, as well as the accuracy of assigning a zero calcium score on routine chest CT was determined.

RESULTS

CAC was most prevalent in the left anterior descending coronary artery in both single and multi-vessel coronary artery disease. There was a strong correlation between the non-gated ordinal and ECG-gated Agatston scores (r = 0.811, p < 0.01). Excellent inter-reader agreement (k = 0.95) was shown for the presence (total ordinal score ≥1) or absence (total ordinal score = 0) of CAC on routine chest CT. The negative predictive value for a total ordinal score of zero on routine CT was 91.6% (95% CI, 85.1-95.9). Total ordinal scores of 0, 1-3, 4-5, and ≥6 corresponded to average Agatston scores of 0.52 (0.3-0.8), 98.7 (78.2-117.1), 350.6 (264.9-436.3) and 1925.4 (1526.9-2323.9).

CONCLUSION

Visual assessment of CAC on non-gated routine chest CT accurately predicts Agatston score ranges, including the zero score, in ECG-gated CT. Inclusion of this information in radiology reports may be useful to convey important information on cardiovascular risk, particularly premature atherosclerosis in younger patients.

Association of homocysteine level and vascular burden and cognitive function in middle-aged and older adults with chronic kidney disease

OBJECTIVES

Patients with chronic kidney disease (CKD) have been found to have cognitive impairment. However, the core features and clinical correlates of cognitive impairment are still unclear. Elevated homocysteine levels are present in CKD, and this is a risk factor for cognitive impairment and vascular diseases in the general population. Thus, this study investigated the core domains of cognitive impairment and investigated the associations of homocysteine level and vascular burden with cognitive function in patients with CKD.

METHODS

Patients with CKD aged ≥ 50 years and age- and sex-matched normal comparisons were enrolled. The total fasting serum homocysteine level was measured. Vascular burden was assessed using the Framingham Cardiovascular Risk Scale. Cognitive function was evaluated using comprehensive neuropsychological tests.

RESULTS

A total of 230 patients with CKD and 92 comparisons completed the study. Memory impairment and executive dysfunction were identified as core features of cognitive impairment in the CKD patients. Among the patients with CKD, higher serum homocysteine levels (β = -0.17, p = 0.035) and higher Framingham Cardiovascular Risk Scale scores (β = -0.18, p = 0.013) were correlated with poor executive function independently. However, an association with memory function was not noted. Our results showed that an elevated homocysteine level and an increased vascular burden were independently associated with executive function, but not memory, in CKD patients.

CONCLUSIONS

This findings suggested the co-existence of vascular and non-vascular hypotheses regarding executive dysfunction in CKD patients. Meanwhile, other risk factors related to CKD itself should be investigated in the future. Copyright © 2015 John Wiley & Sons, Ltd.

Risk factors assessment and risk prediction models in lung cancer screening candidates

From February 2015, low-dose computed tomography (LDCT) screening entered the armamentarium of diagnostic tools broadly available to individuals at high-risk of developing lung cancer. While a huge number of pulmonary nodules are identified, only a small fraction turns out to be early lung cancers. The majority of them constitute a variety of benign lesions. Although it entails a burden of the diagnostic work-up, the undisputable benefit emerges from: (I) lung cancer diagnosis at earlier stages (stage shift); (II) additional findings enabling the implementation of a preventive action beyond the realm of thoracic oncology. This review presents how to utilize the risk factors from distinct categories such as epidemiology, radiology and biomarkers to target the fraction of population, which may benefit most from the introduced screening modality.