Under-reporting of cardiovascular findings on chest CT

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.

Artificial Intelligence Provides Accurate Quantification of Thoracic Aortic Enlargement and Dissection in Chest CT

This study evaluated a deep neural network (DNN) algorithm for automated aortic diameter quantification and aortic dissection detection in chest computed tomography (CT). A total of 100 patients (median age: 67.0 [interquartile range 55.3/73.0] years; 60.0% male) with aortic aneurysm who underwent non-enhanced and contrast-enhanced electrocardiogram-gated chest CT were evaluated. All the DNN measurements were compared to manual assessment, overall and between the following subgroups: (1) ascending (AA) vs. descending aorta (DA); (2) non-obese vs. obese; (3) without vs. with aortic repair; (4) without vs. with aortic dissection. Furthermore, the presence of aortic dissection was determined (yes/no decision). The automated and manual diameters differed significantly (p < 0.05) but showed excellent correlation and agreement (r = 0.89; ICC = 0.94). The automated and manual values were similar in the AA group but significantly different in the DA group (p < 0.05), similar in obese but significantly different in non-obese patients (p < 0.05) and similar in patients without aortic repair or dissection but significantly different in cases with such pathological conditions (p < 0.05). However, in all the subgroups, the automated diameters showed strong correlation and agreement with the manual values (r > 0.84; ICC > 0.9). The accuracy, sensitivity and specificity of DNN-based aortic dissection detection were 92.1%, 88.1% and 95.7%, respectively. This DNN-based algorithm enabled accurate quantification of the largest aortic diameter and detection of aortic dissection in a heterogenous patient population with various aortic pathologies. This has the potential to enhance radiologists' efficiency in clinical practice.

Cardiac Incidental Findings on Abdominopelvic Computed Tomography: Prevalence and Association with Subsequent Cardiovascular Events

PURPOSE

The aim of this study was to assess the prevalence of reportable cardiac findings detected on abdominopelvic CTs and the association with subsequent cardiovascular events.

MATERIALS AND METHODS

We performed a retrospective search of electronic medical record of patients who underwent abdominopelvic CT between November 2006 and November 2011 with a clinical history of upper abdominal pain. A radiologist blinded to the original CT report reviewed all 222 cases for the presence of pertinent reportable cardiac findings. The original CT report was also evaluated for documentation of pertinent reportable cardiac findings. The following findings were recorded on all CTs: presence of coronary calcification, fatty metaplasia, ventricle wall thinning and thickening, valve calcification or prosthesis, heart/chamber enlargement, aneurysm, mass, thrombus, device, air within ventricles, abnormal pericardium, prior sternotomy, and adhesions if prior sternotomy. Medical records were reviewed to identify cardiovascular events on follow-up in patients with the presence or absence of cardiac findings. We compared the distribution findings in patients with and without cardiac events using the Wilcoxon test (for continuous variables) and the Pearson's chi-squared test (for categorical variables).

RESULTS

Eighty-five of 222 (38.3%) patients (52.7% females, median age 52.5 years) had at least one pertinent reportable cardiac finding on the abdominopelvic CT, with a total of 140 findings in this group. From the total 140 findings, 100 (71.4%) were not reported. The most common findings seen on abdominal CTs were: coronary artery calcification (66 patients), heart or chamber enlargement (25), valve abnormality (19), sternotomy and surgery signs (9), LV wall thickening (7), device (5), LV wall thinning (2), pericardial effusion (5), and others (3). After a mean follow-up of 43.9 months, 19 cardiovascular events were found in the cohort (transient ischemic attack, cerebrovascular accident, myocardial infarction, cardiac arrest, acute arrhythmia, palpitation, syncope and acute chest pain). Only 1 event occurred in the group of patients with no incidental pertinent reportable cardiac findings (1/137 = 0.73%). All other 18 events occurred in patients with incidental pertinent reportable cardiac findings (18/85 = 21.2%), which was significantly different (p < 0.0001). One out of the total 19 events in the overall group (5.24%) occurred in a patient with no incidental pertinent reportable cardiac findings while 18 of 19 total events (94.74%) occurred with patients with incidental pertinent reportable cardiac findings, which was also significantly different (p < 0.001). Fifteen of the total events (79%) occurred in patients in whom the incidental pertinent reportable cardiac findings were not reported, which was significantly different (p < 0.001) from the four events that occurred in patients in whom the incidental pertinent reportable cardiac findings were reported or had no findings.

CONCLUSIONS

Incidental pertinent reportable cardiac findings are common on abdominal CTs and are frequently not reported by radiologists. These findings are of clinical relevance since patients with pertinent reportable cardiac findings have a significantly higher incidence of cardiovascular events on follow-up.

Benign incidental cardiac findings in chest and cardiac CT imaging

With the continuous expansion of the disease scope of chest CT and cardiac CT, the number of these CT examinations has increased rapidly. In addition to their common indications, many incidental cardiac findings can be observed when carefully evaluating the coronary arteries, valves, pericardium, ventricles, and large vessels. These findings may have clinical significance or risk of complications, but they are sometimes overlooked or may not be described in the final reports. Although most of the incidental findings are benign, timely detection and treatment can improve the management of chronic diseases or reduce the possibility of severe complications. In this review, we summarized the imaging findings, incidence rate, and clinical relevance of some benign cardiac findings such as coronary artery calcification, aortic and mitral valve calcification, aortic calcification, cardiac thrombus, myocardial bridge, aortic dilation, cardiac myxoma, pericardial cyst, and coronary artery fistula. Reporting incidental cardiac findings will help reduce the risk of severe complications or disease deterioration and contribute to the recovery of patients.

What should we do about Coronary Calcification on Thoracic CT?

PURPOSE

Coronary artery calcification is a frequent incidental finding on thoracic computed tomography (CT) performed for non-cardiac indications. On electrocardiogram-gated cardiac CT, it is an established marker of coronary artery disease and is associated with increased risk of subsequent cardiac events.

MATERIALS AND METHODS

This review discusses the current evidence and guidelines regarding the reporting of coronary artery calcification on non-electrocardiogram-gated thoracic CT performed for non-cardiac indications.

RESULTS

For patients undergoing routine thoracic CT, coronary artery calcification is associated with an increased risk of myocardial infarction and mortality. Coronary artery calcification can be accurately assessed on non-gated thoracic CT compared to gated CT. Guidelines support the reporting of coronary artery calcification on thoracic CT. However, radiologist opinions vary. The identification of coronary artery calcification on thoracic CT may identify patients with previously unknown coronary artery disease. For asymptomatic patients this may trigger an assessment of modifiable cardiovascular risk factors and guide the appropriate use of preventative medications.

CONCLUSION

Future research will address whether changing management based on calcification on thoracic CT will improve outcomes and automated assessment of calcification using machine learning techniques.

KEY POINTS

· Coronary artery calcification is a frequent incidental finding on thoracic CT.. · The presence and severity of coronary artery calcification is associated with cardiac outcomes and mortality.. · Reporting coronary artery calcification on thoracic CT is supported by national and international guidelines..

CITATION FORMAT

· Williams MC, Llewellyn O, . What Should We Do About Coronary Calcification on Thoracic CT?. Fortschr Röntgenstr 2022; 194: 833 - 840.

Visual Ordinal Scoring of Coronary Artery Calcium on Contrast-Enhanced and Non-Contrast Chest CT: A Retrospective Study of Diagnostic Performance and Prognostic Utility

Background: Current guidelines recommend visual evaluation of coronary artery calcium (CAC) on all non-gated non-contrast chest CT examinations. However, chest CT examinations are often performed with contrast material administration. Objective: To evaluate diagnostic performance, prognostic utility, and interobserver agreement of visual CAC assessment on chest CT performed for other indications. Methods: This retrospective study included 260 patients (mean age, 60±11 years; 158 male, 102 female) who underwent both non-gated chest CT (contrast-enhanced in 116 patients; non-contrast in 144 patients) and cardiac calcium-score CT within a 12-month interval. A cardiothoracic radiologist visually assessed CAC on chest CT using an ordinal scale (absent, mild, moderate, or severe). Cardiac CT Agatston calcium scores were quantified according to established guidelines and categorized as absent (0), mild (1-99), moderate (100-299), or severe (≥300). Diagnostic performance of chest CT for presence of CAC was assessed using cardiac CT as reference standard. Major adverse cardiac events (MACE) were assessed as a composite of cardiovascular death and myocardial infarction and evaluated using Cox proportional hazards models. A second cardiothoracic radiologist performed visual CAC assessments in a random subset of 50 chest CT examinations to assess interobserver agreement. Results: For presence of any CAC on cardiac CT, contrast-enhanced and non-contrast chest CT had sensitivity of 83% [62/75] and 90% [85/95] (p=.20) and specificity of 100% [41/41] and 100% [49/49] (p=.99). CAC present on cardiac CT was misclassified as absent on 13 contrast-enhanced and 10 non-contrast chest CT examinations; Agatston score was less than 30 in all such patients, and none experienced MACE. Visual ordinal CAC score was associated with MACE for contrast-enhanced [hazard ratio (HR)=4.5 [95% CI 1.2, 16.4], p=.02) and non-contrast (HR=3.4 [95% CI 1.5, 7.8], p=.003) chest CT. Interobserver agreement was excellent for contrast-enhanced (κ =0.95) and non-contrast (κ =0.89) chest CT. Conclusions: Visual ordinal CAC assessment on both contrast-enhanced and non-contrast chest CT has high diagnostic performance, prognostic utility, and interobserver agreement. Clinical Impact: Routine reporting of CAC on all chest CT examinations regardless of clinical indication and contrast material administration could identify a large number of patients with previously unknown CAC who might benefit from preventive treatment.

Radiologist opinions regarding reporting incidental coronary and cardiac calcification on thoracic CT

Objectives

Coronary and cardiac calcification are frequent incidental findings on non-gated thoracic computed tomography (CT). However, radiologist opinions and practices regarding the reporting of incidental calcification are poorly understood.

Methods

UK radiologists were invited to complete this online survey, organised by the British Society of Cardiovascular Imaging (BSCI). Questions included anonymous information on subspecialty, level of training and reporting practices for incidental coronary artery, aortic valve, mitral and thoracic aorta calcification.

Results

The survey was completed by 200 respondents: 10% trainees and 90% consultants. Calcification was not reported by 11% for the coronary arteries, 22% for the aortic valve, 35% for the mitral valve and 37% for the thoracic aorta. Those who did not subspecialise in cardiac imaging were less likely to report coronary artery calcification (p = 0.005), aortic valve calcification (p = 0.001) or mitral valve calcification (p = 0.008), but there was no difference in the reporting of thoracic aorta calcification. Those who did not subspecialise in cardiac imaging were also less likely to provide management recommendations for coronary artery calcification (p < 0.001) or recommend echocardiography for aortic valve calcification (p < 0.001), but there was no difference for mitral valve or thoracic aorta recommendations.

Conclusion

Incidental coronary artery, valvular and aorta calcification are frequently not reported on thoracic CT and there are differences in reporting practices based on subspeciality.

Advances in knowledge

On routine thoracic CT, 11% of radiologists do not report coronary artery calcification. Radiologist reporting practices vary depending on subspeciality but not level of training.

Quantification of the Thoracic Aorta and Detection of Aneurysm at CT: Development and Validation of a Fully Automatic Methodology

Purpose

To develop and validate a deep learning-based system that predicts the largest ascending and descending aortic diameters at chest CT through automatic thoracic aortic segmentation and identifies aneurysms in each segment.

Materials and Methods

In this retrospective study conducted from July 2019 to February 2021, a U-Net and a postprocessing algorithm for thoracic aortic segmentation and measurement were developed by using a dataset (dataset A) that included 315 CT studies split into training, hyperparameter-tuning, and testing sets. The U-Net and postprocessing algorithm were associated with a Digital Imaging and Communications in Medicine series filter and visualization interface and were further validated by using a dataset (dataset B) that included 1400 routine CT studies. In dataset B, system-predicted measurements were compared with annotations made by two independent readers as well as radiology reports to evaluate system performance.

Results

In dataset B, the mean absolute error between the automatic and reader-measured diameters was equal to or less than 0.27 cm for both the ascending aorta and the descending aorta. The intraclass correlation coefficients (ICCs) were greater than 0.80 for the ascending aorta and equal to or greater than 0.70 for the descending aorta, and the ICCs between readers were 0.91 (95% CI: 0.90, 0.92) and 0.82 (95% CI: 0.80, 0.84), respectively. Aneurysm detection accuracy was 88% (95% CI: 86, 90) and 81% (95% CI: 79, 83) compared with reader 1 and 90% (95% CI: 88, 91) and 82% (95% CI: 80, 84) compared with reader 2 for the ascending aorta and descending aorta, respectively.

Conclusion

Thoracic aortic aneurysms were accurately predicted at CT by using deep learning.Keywords: Aorta, Convolutional Neural Network, Machine Learning, CT, Thorax, AneurysmsSupplemental material is available for this article.© RSNA, 2022.

Performance of an Artificial Intelligence-Based Platform Against Clinical Radiology Reports for the Evaluation of Noncontrast Chest CT

RATIONALE AND OBJECTIVES

Research on implementation of artificial intelligence (AI) in radiology workflows and its impact on reports remains scarce. In this study, we aim to assess if an AI platform would perform better than clinical radiology reports in evaluating noncontrast chest computed tomography (CT) scans.

MATERIALS AND METHODS

Consecutive patients who had undergone noncontrast chest CT were retrospectively identified. The radiology reports were reviewed in a binary fashion for reporting of pulmonary lesions, pulmonary emphysema, aortic dilatation, coronary artery calcifications (CAC), and vertebral compression fractures (VCF). CT scans were then processed using an AI platform. The reports' findings and the AI results were subsequently compared to a consensus read by two board-certificated radiologists as reference.

RESULTS

A total of 100 patients (mean age: 64.2 ± 14.8 years; 57% males) were included in this study. Aortic segmentation and calcium quantification failed to be processed by AI in 2 and 3 cases, respectively. AI showed superior diagnostic performance in identifying aortic dilatation (AI: sensitivity: 96.3%, specificity: 81.4%, AUC: 0.89) vs (Reports: sensitivity: 25.9%, specificity: 100%, AUC: 0.63), p <0.001; and CAC (AI: sensitivity: 89.8%, specificity: 100, AUC: 0.95) vs (Reports: sensitivity: 75.4%, specificity: 94.9%, AUC: 0.85), p = 0.005. Reports had better performance than AI in identifying pulmonary lesions (Reports: sensitivity: 97.6%, specificity: 100%, AUC: 0.99) vs (AI: sensitivity: 92.8%, specificity: 82.4%, AUC: 0.88), p = 0.024; and VCF (Reports: sensitivity:100%, specificity: 100%, AUC: 1.0) vs (AI: sensitivity: 100%, specificity: 63.7%, AUC: 0.82), p <0.001. A comparable diagnostic performance was noted in identifying pulmonary emphysema on AI (sensitivity: 80.6%, specificity: 66.7%. AUC: 0.74) and reports (sensitivity: 74.2%, specificity: 97.1%, AUC: 0.86), p = 0.064.

CONCLUSION

Our results demonstrate that incorporating AI support platforms into radiology workflows can provide significant added value to clinical radiology reporting.

The vertebral heart scale on CT is correlated to radiographs in dogs

The vertebral heart scale (VHS) has long been used as an objective standard for evaluation of cardiac silhouette size on thoracic radiographs and plays a key role in the diagnosis as well as the assessment of the severity of canine heart disease. Based on our review of the literature, there has been no published study describing an objective method for measuring overall heart size using computed tomography (CT) in canine patients. The goals of this exploratory prospective method comparison study were to describe a method for objectively evaluating heart size on canine thoracic CT images, determine whether there was a correlation between the VHS when applied to a right lateral thoracic radiograph and a sagittal image of a thoracic CT scan, and determine the effect of cardiac phase on a VHS measured on CT. A method for measuring VHS on canine CT studies was defined. Data were collected on canine patients admitted to The Ohio State Veterinary Medical Center. Each patient received an ECG-gated thoracic CT immediately followed by a right lateral thoracic radiograph. The VHS was measured on non-gated, systolic, and diastolic sagittal CT reformatted images. Our results indicated that cardiac gating may not be necessary when assessing canine heart size on CT. When comparing the VHS on gated and non-gated CT to the VHS on radiographs, there was a moderate to high degree of correlation; however, there was a high degree of variability between CT and radiography.

Dental Trauma on whole Body Trauma CT-An underreported finding

Background

The prevalence of dental injuries (DI) in polytrauma patients is unknown. The purpose of our study was to identify the frequency of dental injuries on whole body CTs acquired in a trauma setting and to estimate how often they are correctly reported by the radiologist.

Methods

In the time period between 2006 and 2018 the radiological database of one university hospital was screened for whole-body trauma CTs. A total of 994 CTs were identified and re-evaluated.

Results

Dental injuries were identified in 127 patients (12.8% of patients). There were 27 women (21.3%) and 100 men (78.7%) with a mean age of 51.0 ± 18.9 years (range 10–96 years). Regarding localization, most findings involved the molars (n = 107, 37.4%), followed by the incisors (n = 81, 28.3%), premolars (n = 59, 20.6%) and canines (n = 39, 13.7%). Most common findings were as follows: luxations (n = 49, 45.8%), followed by crown fractures (n = 46, 43%), root fractures (n = 10, 9.3%), extrusions (n = 1, 0.9%), and intrusions (n = 1, 0.9%). Only 15 findings (11.8% of all patients with dental injuries) were described in the original radiological reports.

Conclusion

DI had a high occurrence in polytrauma patients. A high frequency of underreported dental trauma findings was identified. Radiologists reporting whole-body trauma CT should be aware of possible dental trauma to report the findings adequately.

Reported and Unreported Potentially Important Incidental Findings in Urgent Nonenhanced Abdominal CT for Renal Colic

OBJECTIVE

The aim of the study was to retrospectively evaluate the prevalence of reported and unreported potentially important incidental findings (PIFs) in consecutive nonenhanced abdominal CTs performed specifically for renal colic in the urgent setting.

METHODS

One radiologist, blinded to the finalized report, retrospectively re-evaluated nonenhanced abdominal CTs performed from January to December 2017 on adult patients from the emergency department with the specific request of urgent evaluation for renal colic, searching for PIFs.

RESULTS

The CTs of 312 patients were included in the study. Thirty-eight findings were reported in 38 different CTs, whereas the re-evaluation added 47 unreported findings in 47 different CTs, adding to total of 85 findings (27%). The difference in the proportion of reported and unreported PIFs between the original report and re-evaluation was significant (p < 0.001). No significant difference was found between the age of patients with and without reported findings. The proportion of potentially important findings did not vary significantly among the 3 shifts in the original report and in re-evaluation. The most frequent findings, both reported and unreported, were pleural effusion, lymphadenopathies, and liver nodules.

CONCLUSIONS

Potentially important additional findings are frequently present in urgent nonenhanced abdominal CTs performed for renal colic, and many are not described in the finalized reports. Radiologists should take care not to underreport PIFs even in the urgent setting because of the possible consequences on the patient's health and in order to avoid legal issues, while at the same time satisfying the need for timely and efficient reporting.

Achados cardiovasculares incidentais em tomografias de tórax solicitadas para suspeita de COVID-19

Background

Computed tomography scans of the chest are often requested as a complementary examination to investigate a clinical suspicion of pulmonary disease caused by the novel coronavirus 19 (COVID-19).

Objectives

Our objective was to analyze the prevalence of incidental cardiovascular findings on chest CT scans requested to assess radiological signs suggestive of COVID-19 infection.

Methods

This cross-sectional, descriptive, and retrospective study reviewed 1,444 chest tomographies conducted in the Radiology department of the Hospital de Clínicas Gaspar Vianna, from March 1 to July 30, 2020, describing the prevalence of images suggestive of viral pneumonia by COVID-19 and incidental pulmonary and cardiovascular findings.

Results

The mean age of the patients was 50.6 ± 16.4 years and female sex was more frequent. Computed tomography without contrast was the most frequently used method (97.2%). Aortic and coronary wall calcification and cardiomegaly were the most prevalent cardiovascular findings. CT angiography revealed aortic aneurysms (9.7%), aortic dissection (7.3%) and thoracic aortic ulcers (2.4%).

Conclusions

Incidental cardiovascular findings occurred in about half of the chest CT scans of patients with suspected COVID-19, especially aortic calcifications, cardiomegaly, and coronary calcification.

Reporting incidental coronary, aortic valve and cardiac calcification on non-gated thoracic computed tomography, a consensus statement from the BSCI/BSCCT and BSTI

Incidental coronary and cardiac calcification are frequent findings on non-gated thoracic CT. We recommend that the heart is reviewed on all CT scans where it is visualised. Coronary artery calcification is a marker of coronary artery disease and it is associated with an adverse prognosis on dedicated cardiac imaging and on non-gated thoracic CT performed for non-cardiac indications, both with and without contrast. We recommend that coronary artery calcification is reported on all non-gated thoracic CT using a simple patient-based score (none, mild, moderate, severe). Furthermore, we recommend that reports include recommendations for subsequent management, namely the assessment of modifiable cardiovascular risk factors and, if the patient has chest pain, assessment as per standard guidelines. In most cases, this will not necessitate additional investigations. Incidental aortic valve calcification may also be identified on non-gated thoracic CT and should be reported, along with ancillary findings such as aortic root dilation. Calcification may occur in other parts of the heart including mitral valve/annulus, pericardium and myocardium, but in many cases these are an incidental finding without clinical significance.

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.

The performance of non-ECG gated chest CT for cardiac assessment - The cardiac pathologies in chest CT (CaPaCT) study

PURPOSE

Evaluating the prevalence of CAD on non-ECG gated chest CTs, image quality (IQ) and the clinical performance of the CAD-RADS classification for predicting cardiovascular events (CVE).

METHODS

215 consecutive patients referred for chest CTs between May 2016 and March 2018 were included (3rd-generation DSCT) using non-ECG gated acquisitions with automated tube voltage selection (110kV_qual.ref/40mAs_qual.ref), pitch 2.65-3.0 and individualized contrast media injection protocols. Dedicated cardiac post-processing reconstructions (0.6 mm/0.4 mm/Kernel Bv36) were added to standard chest reconstructions. Two independent cardiac radiologists performed a 3-step analysis. In case of discrepancy, a third reader gave the final decision. Step 1: visual presence of calcifications; 2: scans with calcifications assessed for IQ using a 5-point Likert scale (poor/sufficient/moderate/good/excellent); 3: stenosis severity was analysed in detail (if Likert sufficient-excellent using CAD-RADS). Electronic patient files were checked to see if pathology was previously mentioned (incidental) and whether patients developed an CVE during follow-up.

RESULTS

1: Calcifications were present in 156/215 cases (72.6 %), 74 of these were incidental. 2: In 68/156 (43.6 %) patients with calcifications IQ was rated sufficient-excellent. 3: CAD-RADS≥3 was seen in 39/68 patients (57.4 %), 12 times (30.8 %) findings were incidental. During follow-up (median 16 [0-35] months), 7/39 (18 %) patients with CAD-RADS≥3 developed a CVE. 17 patients died during follow-up.

CONCLUSION

Coronary calcification on non ECG-gated chest CTs was detected in 72.6 % of patients, cardiac assessment was feasible in nearly half of these patients. Only patients with a CAD-RADS≥3 developed CVE, therefore the CAD-RADS may help identify and guide patients at risk of future CVE.

Incidental findings on CT angiography of the head and neck in stroke patients. Evaluation of frequency and detection rate

OBJECTIVE

A comprehensive CT algorithm in suspected ischemic stroke consists of a native CT scan, CT perfusion imaging of the brain and a CT angiography from the aortic arch to the vertex. Besides core findings of the brain and targeted vessels, various other findings may be identified. We analyzed a large patient sample and estimated the frequency of incidental findings (IFs) and whether these findings were correctly mentioned in the radiological reports.

PATIENTS AND METHODS

In the time period between 01/16 and 02/19 the radiological database of one hospital containing 1625 patients admitted for stroke suspicion were retrospectively evaluated. In total 1175 patients with ischemic stroke CTs were included. IFs were classified according to Lumbreras et al. for their clinical relevance. The primary radiological report was used to classify, whether the finding was reported initially or not.

RESULTS

Overall, 1988 IFs were identified in 1175 patients (mean 1.7 findings per patient). The most frequent finding were thyroid incidentalomas with n = 461 (23.2 % of all findings), followed by signs of mucosal swelling and/or opacification of the nasal sinus (n = 391, 19.7 %). Regarding clinical relevance, 181 findings were of major relevance (9.1 % of all findings), 902 were of moderate relevance (45.4 %) and 905 were of minor relevance (45.5 %). Overall, 772 findings (38.8 %) were not reported and 1216 (61.2 %) were sufficiently reported by the radiologist.

CONCLUSION

The present study corroborates that incidental findings are frequent in patients undergoing ischemic stroke CT, which are about half of moderate and major relevance. About 40 % of these findings were not mentioned in the primary radiology report, including findings of high clinical relevance. The radiologist should be aware of these findings.

Cardiovascular findings on cross-sectional imaging: spectrum of incidental and critical findings and clinical relevance for the abdominal radiologist

Although not the primary focus of the exams, cardiovascular structures are included to some extent on all abdominal or whole-body cross-sectional studies. Cardiovascular findings often present incidentally and may range from chronic to acute and emergent pathologies. Among the most common cardiovascular findings are the presence of cardiac calcifications, most commonly coronary, which correlate with the presence of coronary artery and valvular disease. Signs of myocardial ischemia, both acute and chronic, and its complications may also be visualized. Cardiac filling defects most commonly represent thrombus and are associated with systemic arterial embolic complications. Pericardial findings often manifest as effusion or thickening, which may lead to hemodynamic consequences visible at imaging. Incidental pulmonary emboli and systemic venous thrombi may be incidentally detected, particularly in hospitalized and oncologic patients, and warrant immediate attention. This review will highlight the appearance of common and important incidental cardiovascular findings and related pitfalls and discuss reporting and follow-up recommendations relevant to the abdominal radiologist.

Managing Incidental Findings on Thoracic CT: Mediastinal and Cardiovascular Findings. A White Paper of the ACR Incidental Findings Committee

The ACR Incidental Findings Committee presents recommendations for managing incidentally detected mediastinal and cardiovascular findings found on CT. The Chest Subcommittee was composed of thoracic radiologists who developed the provided guidance. These recommendations represent a combination of current published evidence and expert opinion and were finalized by informal iterative consensus. The recommendations address the most commonly encountered mediastinal and cardiovascular incidental findings and are not intended to be a comprehensive review of all incidental findings associated with these compartments. Our goal is to improve the quality of care by providing guidance on how to manage incidentally detected thoracic findings.

The role of standard non-ECG gated chest CT in cardiac assessment: design and rationale of the Cardiac Pathologies in standard chest CT (CaPaCT) study

Modern high-performance computed tomography (CT) scanners with improved scan acquisition times now allow for routine assessment of cardiac pathologies on chest CTs, which can result in numerous incidental cardiac findings. The CaPaCT study, an observer blinded, single-centre study, aims to assess the visibility, management and possible clinical impact of incidental cardiac pathologies that are now becoming visible on standard chest CTs. A total of 217 consecutive patients referred for a chest CT on a high-performance third-generation dual-source CT scanner will be included. Tube voltage settings will be chosen via automated kV selection. Dedicated cardiac reconstructions will be added to the standard post-processing: 0.6-mm slice thickness, 0.4-mm increment and Bv36 kernel (iterative reconstruction/strength 3). Primary endpoints will be the presence and extent of coronary artery disease (CAD) assessed via a 17-segment model. These data will be collected and analysed by two experienced, blinded cardiac radiologists. Furthermore, information on aortic and mitral valve morphology/calcification and pericardial abnormalities will be collected. The CAD Reporting and Data System classification will subsequently be used to assess the management and possible clinical burden of any incidentally detected CAD. Additionally, objective and subjective image quality (attenuation, contrast-to-noise, signal-to-noise and 5-point Likert scale) of the obtained cardiac reconstructions will be assessed.

Cardiovascular findings on computed tomography in patients with unclear finding situation and trauma of unknown origin

Incidental cardiovascular findings are common and can be found in up to 70% of patients. Previously, several reports about incidental findings (IFs) on whole body computed tomography (CT) were published. However, no previous study investigated cardiovascular IFs in patients with unclear finding situation and trauma of unknown origin on whole body CT.The radiological database of 2 university hospitals was screened for patients with trauma of unknown origin and unclear finding situation investigated by whole body CT. The images were retrospectively analyzed by 2 radiologists in consensus. The findings were classified according to their clinical relevance. Clinically nonrelevant findings like valvular sclerosis, aortic sclerosis, or anatomic variants were excluded from this study. Moreover, the radiology reports were analyzed to assess initial reporting by the radiologist.Overall, we identified 60 patients with a mean age of 63 years. A total of 98 clinically relevant cardiovascular IFs (CRCIF) were identified in 60 (75%) patients (1.6 CRCIF per patient). The most prevalent finding was cardiomegaly in 23 patients, followed by coronary sclerosis in 21 patients and aortic ectasia in 11 patients; other findings were rarer. Sixty-one findings were reported (62.2%) and 37 were nonreported (37.8%). Thirty patients (50%) showed no traumatic event on whole body CT.CRCIFs are common in patients with unclear finding situation and trauma of unknown origin. Despite initial indication for trauma detection, the whole body CT should carefully be evaluated for CRCIF because of the high prevalence of clinically relevant findings. Notably, 37.76% of the findings were not reported by the radiologist.

Incidental extravascular findings in computed tomographic angiography for planning or monitoring endovascular aortic aneurysm repair: Smoker patients, increased lung cancer prevalence?

AIM

To validate the feasibility of high resolution computed tomography (HRCT) of the lung prior to computed tomography angiography (CTA) in assessing incidental thoracic findings during endovascular aortic aneurysm repair (EVAR) planning or follow-up.

METHODS

We conducted a retrospective study among 181 patients (143 men, mean age 71 years, range 50-94) referred to our centre for CTA EVAR planning or follow-up. HRCT and CTA were performed before or after 1 or 12 mo respectively to EVAR in all patients. All HRCT examinations were reviewed by two radiologists with 15 and 8 years’ experience in thoracic imaging. The results were compared with histology, bronchoscopy or follow-up HRCT in 12, 8 and 82 nodules respectively.

RESULTS

There were a total of 102 suspected nodules in 92 HRCT examinations, with a mean of 1.79 nodules per patient and an average diameter of 9.2 mm (range 4-56 mm). Eighty-nine out of 181 HRCTs resulted negative for the presence of suspected nodules with a mean smoking history of 10 pack-years (p-y, range 5-18 p-y). Eighty-two out of 102 (76.4%) of the nodules met criteria for computed tomography follow-up, to exclude the malignant evolution. Of the remaining 20 nodules, 10 out of 20 (50%) nodules, suspected for malignancy, underwent biopsy and then surgical intervention that confirmed the neoplastic nature: 4 (20%) adenocarcinomas, 4 (20%) squamous cell carcinomas, 1 (5%) small cell lung cancer and 1 (5%) breast cancer metastasis); 8 out of 20 (40%) underwent bronchoscopy (8 pneumonia) and 2 out of 20 (10%) underwent biopsy with the diagnosis of sarcoidosis.

CONCLUSION

HRCT in EVAR planning and follow-up allows to correctly identify patients requiring additional treatments, especially in case of lung cancer.

Radiological findings on irradiation-CT in patients with non metastatic breast cancer

OBJECTIVE

The aim of this study was to evaluate the number of incidental findings on native CT treatment-planning scans for radiation in breast cancer patients.

METHODS

The treatment-planning scans of 382 patients with non-metastatic breast cancer were retrospectively analyzed for additional findings. The planning scan area covered the entire thorax and the upper part of the abdomen. Incidental findings were classified according to their clinical relevance.

RESULTS

Overall 892 incidental findings were detected in the CT treatment-planning scans (mean 2.34 findings per patient). Only a small proportion of patients (n = 63, 16.4%) had no finding. Most findings were located in the thorax (683, 76.57%), and 209 findings (23.43%) were abdominal. 79 findings (8.87%) were of major clinical relevance, 232 findings (26.01%) were of moderate clinical relevance and 580 findings (65.02%) were of minor clinical relevance. Most clinically relevant findings were in the thorax (p = 0.006). Abdominal findings were more of significantly minor clinical relevance (p < 0.0001).

CONCLUSION

Radiological findings are frequent in native CT treatment-planning scans for radiation of breast cancer patients. Therefore, the radiologist should use this performed sectional image to obtain additional information of the patient. Advances in knowledge: Treatment-planning CT scans can show several radiological findings, namely 2.34 findings per patient. Major clinically relevant findings account for 8.87%.

Impact on mortality of coronary and non-coronary cardiovascular findings in non-gated thoracic CT by malignancy status

PURPOSE

The prognostic value of coronary artery calcification (CAC) assessed on non-gated thoracic CT scans has only been explored in population-based studies. We explored the impact of the presence and extension of CAC, as well as of non-coronary atherosclerosis cardiovascular findings (NCACVF) in survival of patients with and without malignancies undergoing clinically indicated non-gated thoracic computed tomography (CT) scans.

MATERIALS AND METHODS

Between August and December 2012, a total of 1.901 patients aged between 35 and 74 years underwent clinically indicated non-gated, non-enhanced thoracic CT scans and followed for mortality through September 2016.

RESULTS

Three hundred and thirty two (17.5%), 250 (13.2%), and 329 (17.3%) patients showed CAC in 1, 2, and 3 vessels, respectively, and the remaining had no CAC. Two hundred and fifty five (13.4%) patients had evidence of extensive calcification (CACSIS>5). Only 62 (3.3%) had major NCACVF whereas 1635 (86%) had none or minimal NCACVF. After a median follow-up of 3.7 (3.5-3.9) years, 217 (11.4%) deaths occurred. Age [HR 1.03 (95% CI 1.01-1.05), p=0.001], a history of malignancy [HR 8.04 (95% CI 5.95-10.9), p<0.0001], and the NCACVF class [HR 1.79 (95% CI 1.45-2.19), p<0.0001] were identified as independent predictors of death. CACSIS was found an independent predictor of death only among patients without malignancy (HR 1.10 (95% CI 1.02-1.20), p=0.019).

CONCLUSIONS

In this study including clinically indicated non-gated standard thoracic CT scans, survival rates were associated to the CAC extension among patients without malignancy, and to the NCACVF class independent from the malignancy status.

Prognostic value of visually detected coronary artery calcification on unenhanced non-gated thoracic computed tomography for prediction of non-fatal myocardial infarction and all-cause mortality

PURPOSE

To determine the prognostic value of visually detected coronary artery calcification (CAC) on unenhanced non-gated thoracic computed tomography (CT) for non-fatal myocardial infarction (MI) and all-cause mortality.

METHODS

This retrospective single-centre cohort study comprised of 410 consecutive patients aged 40-80 years without any known cardiovascular disease at baseline. CT images without electrocardiogram-gating were acquired for a variety of respiratory medicine indications. CAC was examined by a single reader blinded to clinical data and outcome, using 1) the Agatston coronary calcium score (CCS), 2) visual CAC and 3) number of visually calcified coronary arteries.

RESULTS

Visible CAC was identified in 201 (49.0%) of the 410 patients (60.5 ± 10.0 years old, 42.4% males). After a median follow up of 7.0 years, 39 patients (9.5%) experienced an event (death or non-fatal MI). After adjustment for cardiovascular risk factors, those with 1) higher CCS, 2) presence of visual CAC or 3) greater number of calcified coronary arteries by visual assessment, had an increased risk of adverse outcome (all p-value <0.05). There was no significant difference in c-statistics of the three methods of assessment (0.81, 0.80, 0.81 respectively), indicating that simple visual assessment of CAC may have a prognostic value similar to CCS.

CONCLUSION

Among patients with no known cardiovascular disease who underwent unenhanced non-gated CT for a pulmonary-related indication, visually detected CAC was a strong independent predictor of non-fatal MI and all-cause mortality.

[Clinically relevant incidental cardiovascular findings in CT examinations]

BACKGROUND AND METHOD

Incidental cardiovascular findings are a frequent phenomenon in computed tomography (CT) examinations. As the result of a dedicated PubMed search this article gives a systemic overview of the current literature on the most important incidental cardiovascular findings, their prevalence and clinical relevance.

RESULTS

The majority of incidental cardiovascular findings are of only low clinical relevance; however, highly relevant incidental findings, such as aortic aneurysms, thromboses and thromboembolic events can also occasionally be found, especially in oncology patients.

CONCLUSION

The scans from every CT examination should also be investigated for incidental findings as they can be of decisive importance for the further clinical management of patients, depending on their clinical relevance.

High pitch third generation dual-source CT: Coronary and cardiac visualization on routine chest CT

BACKGROUND

Chest CT scans are frequently performed in radiology departments but have not previously contained detailed depiction of cardiac structures.

OBJECTIVES

To evaluate myocardial and coronary visualization on high-pitch non-gated CT of the chest using 3rd generation dual-source computed tomography (CT).

METHODS

Cardiac anatomy of patients who had 3rd generation, non-gated high pitch contrast enhanced chest CT and who also had prior conventional (low pitch) chest CT as part of a chest abdomen pelvis exam was evaluated. Cardiac image features were scored by reviewers blinded to diagnosis and pitch. Paired analysis was performed.

RESULTS

3862 coronary segments and 2220 cardiac structures were evaluated by two readers in 222 CT scans. Most patients (97.2%) had chest CT for oncologic evaluation. The median pitch was 2.34 (IQR 2.05, 2.65) in high pitch and 0.8 (IQR 0.8, 0.8) in low pitch scans (p < 0.001). High pitch CT showed higher image visualization scores for all cardiovascular structures compared with conventional pitch scans (p < 0.0001). Coronary arteries were visualized in 9 coronary segments per exam in high pitch scans versus 2 segments for conventional pitch (p < 0.0001). Radiation exposure was lower in the high pitch group compared with the conventional pitch group (median CTDIvol 10.83 vs. 12.36 mGy and DLP 790 vs. 827 mGycm respectively, p < 0.01 for both) with comparable image noise (p = 0.43).

CONCLUSION

Myocardial structure and coronary arteries are frequently visualized on non-gated 3rd generation chest CT. These results raise the question of whether the heart and coronary arteries should be routinely interpreted on routine chest CT that is otherwise obtained for non-cardiac indications.