Small coronary calcifications are not detectable by 64-slice contrast enhanced computed tomography

Recently, small calcifications have been associated with unstable plaques. Plaque calcifications are both in intravascular ultrasound (IVUS) and multi-slice computed tomography (MSCT) easily recognized. However, smaller calcifications might be missed on MSCT due to its lower resolution. Because it is unknown to which extent calcifications can be detected with MSCT, we compared calcification detection on contrast enhanced MSCT with IVUS. The coronary arteries of patients with myocardial infarction or unstable angina were imaged by 64-slice MSCT angiography and IVUS. The IVUS and MSCT images were registered and the arteries were inspected on the presence of calcifications on both modalities independently. We measured the length and the maximum circumferential angle of each calcification on IVUS. In 31 arteries, we found 99 calcifications on IVUS, of which only 47 were also detected on MSCT. The calcifications missed on MSCT (n = 52) were significantly smaller in angle (27° ± 16° vs. 59° ± 31°) and length (1.4 ± 0.8 vs. 3.7 ± 2.2 mm) than those detected on MSCT. Calcifications could only be detected reliably on MSCT if they were larger than 2.1 mm in length or 36° in angle. Half of the calcifications seen on the IVUS images cannot be detected on contrast enhanced 64-slice MSCT angiography images because of their size. The limited resolution of MSCT is the main reason for missing small calcifications

Unrequested Findings on Cardiac Computed Tomography: Looking Beyond the Heart

Objectives: To determine the prevalence of clinically relevant unrequested extra-cardiac imaging findings on cardiac Computed Tomography (CT) and explanatory factors thereof. Methods: A systematic review of studies drawn from online electronic databases followed by meta-analysis with metaregression was performed. The prevalence of clinically relevant unrequested findings and potentially explanatory variables were extracted (proportion of smokers, mean age of patients, use of full FOV, proportion of men, years since publication). Results: Nineteen radiological studies comprising 12922 patients met the inclusion criteria. The pooled prevalence of clinically relevant unrequested findings was 13 % (95 % confidence interval 9–18, range: 3–39%). The large differences in prevalence observed were not explained by the predefined (potentially explanatory) variables. Conclusions: Clinically relevant extra-cardiac findings are common in patients undergoing routine cardiac CT, and their prevalence differs substantially between studies. These differences may be due to unreported factors such as different definitions of clinical relevance and differences between populations. We present suggestions for basic reporting whic

Cardiovascular disease prediction : do pulmonary disease-related chest CT features have added value?

Certain pulmonary diseases are associated with cardiovascular disease (CVD). Therefore we investigated the incremental predictive value of pulmonary, mediastinal and pleural features over cardiovascular imaging findings. A total of 10,410 patients underwent diagnostic chest CT for non-cardiovascular indications. Using a case-cohort approach, we visually graded CTs from the cases and from an approximately 10 % random sample of the baseline cohort (n = 1,203) for cardiovascular, pulmonary, mediastinal and pleural findings. The incremental value of pulmonary disease-related CT findings above cardiovascular imaging findings in cardiovascular event risk prediction was quantified by comparing discrimination and reclassification. During a mean follow-up of 3.7 years (max. 7.0 years), 1,148 CVD events (cases) were identified. Addition of pulmonary, mediastinal and pleural features to a cardiovascular imaging findings-based prediction model led to marginal improvement of discrimination (increase in c-index from 0.72 (95 % CI 0.71-0.74) to 0.74 (95 % CI 0.72-0.75)) and reclassification measures (net reclassification index 6.5 % (p <0.01)). Pulmonary, mediastinal and pleural features have limited predictive value in the identification of subjects at high risk of CVD events beyond cardiovascular findings on diagnostic chest CT scans

Incidental imaging findings from routine chest CT used to identify subjects at high risk of future cardiovascular events

PURPOSE: To investigate the contribution of incidental findings at chest computed tomography (CT) in the detection of subjects at high risk for cardiovascular disease (CVD) by deriving and validating a CT-based prediction rule. MATERIALS AND METHODS: This retrospective study was approved by the ethical review board of the primary participating facility, and informed consent was waived. The derivation cohort comprised 10 410 patients who underwent diagnostic chest CT for noncardiovascular indications. During a mean follow-up of 3.7 years (maximum, 7.0 years), 1148 CVD events (cases) were identified. By using a case-cohort approach, CT scans from the cases and from an approximately 10% random sample of the baseline cohort (n = 1366) were graded visually for several cardiovascular findings. Multivariable Cox proportional hazards analysis with backward elimination technique was used to derive the best-fitting parsimonious prediction model. External validation (discrimination, calibration, and risk stratification) was performed in a separate validation cohort (n = 1653). RESULTS: The final model included patient age and sex, CT indication, left anterior descending coronary artery calcifications, mitral valve calcifications, descending aorta calcifications, and cardiac diameter. The model demonstrated good discriminative value, with a C statistic of 0.71 (95% confidence interval: 0.68, 0.74) and a good overall calibration, as assessed in the validation cohort. This imaging-based model allows accurate stratification of individuals into clinically relevant risk categories. CONCLUSION: Structured reporting of incidental CT findings can mediate accurate stratification of individuals into clinically relevant risk categories and subsequently allow those at higher risk of future CVD events to be distinguished

Incidental findings on chest CT imaging are associated with increased COPD exacerbations and mortality

Background This study aimed to evaluate whether incidental CT findings of emphysema, airway thickening and bronchiectasis, as seen on CT scans performed for other non-pulmonary clinical indications, are associated with future acute exacerbations of COPD resulting in hospitalisation or death. Methods This multicentre prospective case-cohort study comprised 6406 subjects who underwent routine diagnostic chest CT for non-pulmonary indications. Using a case-cohort approach, we visually graded CT scans from cases and a random sample of similar to 10% of the baseline cohort (n=704) for emphysema severity (range 0-20), airway thickening (range 0-5) and bronchiectasis (range 0-5). We used weighted Cox proportional hazards analysis to assess the independent association between CT findings and hospitalisation or death due to COPD exacerbation. Results During a median follow-up of 4.4 years (maximum 5.2 years), 338 COPD events were identified. The risk of experiencing a future acute exacerbation of COPD resulting in hospitalisation or death was significantly increased in subjects with severe emphysema (score >= 7) and severe airway thickening (score >= 3). The respective HRs were 4.6 (95% CI 3.0 to 7.1) and 5.9 (95% CI 3.4 to 10.5). Severe bronchiectasis (score >= 3) was not significantly associated with increased risk of adverse events (HR 1.5; 95% CI 0.9 to 2.5). Conclusions Morphological correlates of COPD such as emphysema and airway thickening detected on CT scans obtained for other non-pulmonary indications are strong independent predictors of subsequent development of acute exacerbations of COPD resulting in hospitalisation or death

Validation of an imaging based cardiovascular risk score in a Scottish population

Objectives A radiological risk score that determines 5-year cardiovascular disease (CVD) risk using routine care CT and patient information readily available to radiologists was previously developed. External validation in a Scottish population was performed to assess the applicability and validity of the risk score in other populations. Methods 2915 subjects aged ≥40 years who underwent routine clinical chest CT scanning for non-cardiovascular diagnostic indications were followed up until first diagnosis of, or death from, CVD. Using a case-cohort approach, all cases and a random sample of 20% of the participant's CT examinations were visually graded for cardiovascular calcifications and cardiac diameter was measured. The radiological risk score was determined using imaging findings, age, gender, and CT indication. Results Performance on 5-year CVD risk prediction was assessed. 384 events occurred in 2124 subjects during a mean follow-up of 4.25 years (0–6.4 years). The risk score demonstrated reasonable performance in the studied population. Calibration showed good agreement between actual and 5-year predicted risk of CVD. The c-statistic was 0.71 (95%CI:0.67-0.75). Conclusions The radiological CVD risk score performed adequately in the Scottish population offering a potential novel strategy for identifying patients at high risk for developing cardiovascular disease using routine care CT data

Selected items from STROBE checklist, together with percentage and number of articles in which items were scored ‘yes’.

<p>Selected items from STROBE checklist, together with percentage and number of articles in which items were scored ‘yes’.</p

Overview of included articles with abstracted parameters.

<p>*depending on protocol used. EBT  =  Electron Beam Tomography. References for <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone-0032184-g003" target="_blank">figure 3:</a> Venkatesh <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Venkatesh1" target="_blank">[40]</a>, Lazoura <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Lazoura1" target="_blank">[29]</a>, Aglan <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Aglan1" target="_blank">[27]</a>, Koonce <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Koonce1" target="_blank">[19]</a>, Chia <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Chia1" target="_blank">[33]</a>, Lehman <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Lehman1" target="_blank">[34]</a>, Machaalany <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Machaalany1" target="_blank">[28]</a>, Kim <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Kim1" target="_blank">[26]</a>, Dewey <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Dewey1" target="_blank">[41]</a>, Greenberg <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-GreenbergWolff1" target="_blank">[22]</a>, Law <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Law1" target="_blank">[20]</a>, Kawano <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Kawano1" target="_blank">[42]</a>, Kirsch <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Kirsch2" target="_blank">[32]</a>, Mueller <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Mueller2" target="_blank">[30]</a>, Haller <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Haller1" target="_blank">[43]</a>, Onuma <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Onuma1" target="_blank">[35]</a>, Schragin <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Schragin1" target="_blank">[21]</a>, Horton <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Horton1" target="_blank">[44]</a>, Hunold <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032184#pone.0032184-Hunold1" target="_blank">[25]</a>.</p

Flowchart illustrating literature search and selection procedure.

<p>Flowchart illustrating literature search and selection procedure.</p

Validation of an imaging based cardiovascular risk score in a Scottish population

Objectives A radiological risk score that determines 5-year cardiovascular disease (CVD) risk using routine care CT and patient information readily available to radiologists was previously developed. External validation in a Scottish population was performed to assess the applicability and validity of the risk score in other populations. Methods 2915 subjects aged ≥40 years who underwent routine clinical chest CT scanning for non-cardiovascular diagnostic indications were followed up until first diagnosis of, or death from, CVD. Using a case-cohort approach, all cases and a random sample of 20% of the participant's CT examinations were visually graded for cardiovascular calcifications and cardiac diameter was measured. The radiological risk score was determined using imaging findings, age, gender, and CT indication. Results Performance on 5-year CVD risk prediction was assessed. 384 events occurred in 2124 subjects during a mean follow-up of 4.25 years (0–6.4 years). The risk score demonstrated reasonable performance in the studied population. Calibration showed good agreement between actual and 5-year predicted risk of CVD. The c-statistic was 0.71 (95%CI:0.67-0.75). Conclusions The radiological CVD risk score performed adequately in the Scottish population offering a potential novel strategy for identifying patients at high risk for developing cardiovascular disease using routine care CT data