Incidental findings on cardiac computed tomography. Should we look?

Frequency of extracardiac findings on "negative" CT coronary angiography studies

AIM

To evaluate the prevalence and nature of extracardiac findings identified on computed tomography (CT) coronary angiography (CTCA) in patients with chest pain but without evidence of coronary artery disease (CAD).

MATERIALS AND METHODS

CTCA studies in patients referred to the hospital between January 2017 to February 2021 with chest pain and a suspected diagnosis of CAD were reviewed retrospectively for the presence of extracardiac findings. Consensus review of CTCA studies was performed by two experienced thoracic radiologists. The presence and severity of extracardiac findings, together with the likelihood that chest pain might be attributed to these, was recorded. Patient records were reviewed to ascertain the recording of extracardiac findings on initial CTCA reports and, where applicable, the nature of the follow-up.

RESULTS

Extracardiac findings (n=210) were present in 110/180 patients (61%) with a mean of 1.9 findings per patient. Extracardiac findings were more prevalent in patients aged ≥65 years compared to those <65 years (p<0.001). At least one extracardiac finding with the potential to cause chest pain was present in 40 patients (22%): degenerative disc disease (n=23 [13%]) and hiatus hernia (n=6 [3.3%]) were the most common extracardiac findings. Only 37.6% (79) of all retrospectively identified findings had been initially reported and, of these, 12.7% (10) required further follow-up.

CONCLUSION

Extracardiac findings are common in patients with no evidence of CAD on CTCA. The entire dataset should be evaluated for the presence of extracardiac findings that could explain chest pain symptoms on wide field of view reconstructions.

Incidental findings on coronary computed tomography in women with selected reproductive disorders

OBJECTIVE

To determine the prevalence of incidental findings (IFs) on coronary computed tomography (CCT) in women aged 45-55 years and previously diagnosed with reproductive disorders such as polycystic ovary syndrome (PCOS), premature ovarian insufficiency (POI) or preeclampsia (PE).

METHODS

A total of 486 middle-aged women with PCOS (n = 101), POI (n = 97) or a history of PE (n = 288) underwent a CCT as part of a prior prospective study. IFs were categorized by their significance (minor, moderate and major). Follow-up information was collected from patients' records. To investigate the impact of different field of views (FOVs), a subset of scans was analyzed in full FOV and small FOV.

RESULTS

In 96/486 (19.8%) women, one or more IFs were detected, of which 54/486 (11.1%) were classified as moderate/major and 48/486 (9.9%) required follow-up. A moderate/major IF was detected in 16/101 (15.9%) women with PCOS, 13/97 (13.4%) women with POI and 25/288 (8.7%) women with a history of PE. In 78 women with an IF detected in the full FOV, the IF was still visible in 60 (76.9%) women in the small FOV. In the full FOV, 46 women required follow-up, but using the small FOV this was reduced to 30 women.

CONCLUSION

Using CCT as a cardiovascular disease screening tool in women with selected reproductive disorders increases the probability of detecting IFs that can cause anxiety and may generate extra costs, but can also reveal clinically relevant findings. Using a small FOV centered around the heart resulted in a lower prevalence of IFs and required less follow-up.

Non-cardiovascular findings on chest CT angiography in children with congenital heart disease: How important are they?

Background

There are only a few publications about the non-cardiovascular findings in children with congenital heart diseases explored by chest CT angiography. The purpose of our study is to evaluate the prevalence of non-cardiovascular findings on chest CT angiographies in children with congenital heart disease and to raise awareness about their importance among the radiologists.

Methods

We retrospectively reviewed the 272 chest CT angiographies performed in our pediatric radiology department between January 2017 and march 2021 and extracted the data of the 180 patients positive for a congenital heart disease. Then from that pool, we sorted out the non-cardiovascular findings into significant and non-significant in regard of their relevance or not in the patient’s management.

Results

Non-cardiovascular lesions were found in 58% (105/180) of our patients, and 49% (88/180) of them presented at least one significant non-cardiac lesion. Lung and airways abnormalities were found in 41% (74/180) of the cases, representing the majority of the non-cardiovascular findings. Syndromic associations were found in 17% (28/180) of our patients, including 14 cases of heterotaxic syndrome.

Conclusion

Non-cardiovascular findings are common in children with congenital heart disease. Reporting these associated lesions is a requisite for an optimal therapeutic management of these children. Radiologists should never forget that a Chest CT angiography in children is first and foremost a chest CT.

Extracardiac findings on cardiac computed tomography in patients undergoing atrial fibrillation catheter ablation

Abstract Background and Aim

To assess the prevalence of incidental extracardiac findings in patients who underwent cardiac CT for the evaluation of left atrial (LA) anatomy before atrial fibrillation (AF) catheter ablation. We also aimed to determine the independent predictors of relevant extracardiac alterations.

Patients and Methods

We studied consecutive patients who underwent cardiac CT with a 256-slice scanner for the visualization of LA anatomy before AF ablation. Prevalence of clinically significant and not significant extracardiac findings were recorded. Moreover, we determined the variables associated with relevant extracardiac alterations with uni- and multivariate logistic regression analyses.

Results

In total, 1,952 consecutive patients who underwent cardiac CT examination between 2010 and 2020 were included in our study (mean age 61.2±10.6 years; 66.2% male). Incidental extracardiac findings were detected in 820 (42.0%; 95%CI=0.40-0.44%) patients, while clinically significant alterations were reported in 416 (21.3%; 95%CI=20.0-23.2%) patients. When analyzing the predictors of clinically relevant alterations, age (OR=1.04; 95%CI=1.03- 1.05), male sex (OR=1.39; 95%CI=1.12-1.73), chest pain (OR=1.46; 95%CI=1.09-1.93), hypertension (OR=1.42; 95%CI=1.12-1.81), heart failure (OR=1.68; 95%CI=1.09-2.53), obstructive CAD (OR=1.56; 95%CI=1.16-2.09) and prior stroke/TIA (OR=1.56; 95%CI=1.04- 2.30) showed association with clinically significant incidental findings in the univariate analysis (all p<0.05). In the multivariate analysis, age (OR=1.04; 95%CI=1.02-1.06; p<0.001) proved to be the only significant predictor of clinically relevant extracardiac finding.

Conclusion

Cardiac CT performed before AF ablation is not only helpful in understanding LA anatomy, but might also identify clinically significant pathologies. These incidental findings might have further diagnostic or therapeutic consequences.

Incidental findings on emergency CT scans: Predictive factors and medico-economic impact

PURPOSE

The main objective was to evaluate types and predictive factors of incidental findings (IFs) on multidetector computed tomographies (MDCTs) performed for an emergency department (ED). The secondary aim was to analyze additional investigations, their benefits, side effects, costs and the final diagnoses.

METHOD

One thousand consecutive patients over 18 years old who underwent an MDCT in the ED of our institution from January 2011 to November 2011 were retrospectively included, accounting for 300 head MDCTs and 700 other MDCTs. The following criteria were collected in patient electronic medical records: IFs (divided into low and high clinical significance), body areas covered, availability of a prior imaging, radiologist's experience and subspecialty, additional investigations, their outcomes and costs.

RESULTS

Among the 1000 included patients, 232 had at least one IF and 122 had at least one IF of high clinical significance (IFCS). There were 340 IFs and 150 IFCSs. A significant association with the presence of at least one IF was noted for older patients, less-experienced radiologists, no subspecialty of the radiologist, the abdominopelvic area, and the absence of prior imaging. Eighteen IFs generated additional investigations in our institution, including five invasive samplings and three surgical operations, with two diagnoses of malignancy (a gastrointestinal stromal tumor and a Bosniak IV cystic renal lesion). One benign iatrogenic complication occurred. Total cost of these investigations was €41,247 (with an average of €2292 per IF investigated).

CONCLUSION

IFs on emergency MDCTs were frequent, rarely severe, rarely iatrogenic and relatively expensive.

Incidental Non-cardiac Findings in Coronary Computed Tomography Angiography: Is it Worth Reporting?

Objectives:

The objectives of this study were to estimate the prevalence and significance of incidental non-cardiac findings (INCFs) in coronary computed tomography angiography (CCTA) using a dual-source multidetector computed tomography.

Materials and Methods:

Retrospective review of all CCTA studies performed over a time period for various indications was included in the study. After exclusions, CCTA of 1713 patients was evaluated by two experienced cardiac radiologists for non-cardiac abnormalities in the full field-of-view limited contrast chest series. The scans were acquired from the level of the carina to just below the diaphragm. INCFs were classified into three categories: Significant, indeterminate, and insignificant findings based on their clinical impact and availability of prior imaging and clinical details.

Results:

The study cohort consisted of 1123 males (mean age of 58 years) and 590 females (mean age of 64 years). INCFs were seen in 600 patients of 1713 patients. A total of 812 INCFs (47.5%) were found in 1713 patients. Of those, 568 (70%) were considered insignificant, 205 (25.2%) indeterminate, and 39 significant findings (4.9%). The prevalence of significant findings was 2.3%. Among the 39 significant findings, after correlating with clinical details and other imaging, nine were really significant findings (0.5%) and out of this, four turned out to be cancers (0.2%).

Conclusion:

Large number of INCFs can be found in CCTA with majority of them being insignificant or of minimal clinical impact. Although the proportion of significant findings is small and may not be cost beneficial, it is prudent to evaluate all the available data and to make appropriate classification of INCFs which can help in further management.

Incidental Non-cardiac Findings in Cardiovascular Imaging

Improvements in imaging techniques have led to an expansion in the number of cross-sectional cardiac studies being performed. This means that incidental non-cardiac findings (INCF) identified on cardiac imaging have become an important clinical concern. The majority of INCF are not clinically significant. However, some INCF will require follow-up or changes in management. Differentiating clinically significant from non-significant INCF can be challenging, particularly given the breadth of potential findings and the range of organ systems involved. Following up INCF also has economic implications. Recent changes to the lung nodule follow-up guidelines will reduce the cost of following up incidental lung nodules. In this manuscript, we discuss the common and important INCF which may be identified in cardiovascular imaging and explore potential implications of these findings.

Extracardiac findings on coronary computed tomography angiography in patients without significant coronary artery disease

OBJECTIVE

To analyse extracardiac findings in patients without significant coronary artery disease (CAD) in general and in symptomatic patients in particular.

METHODS

We searched the Radiology Information System database for coronary computed tomography angiographies (CTA) performed from 2000-2014 and retrospectively enrolled 3,898 patients without significant CAD (coronary stenosis < 50%) in CTA. In 2,330 symptomatic patients, we analysed the spectrum of extracardiac findings and identified pathologies potentially explaining chest pain. Finally, we investigated variables affecting the number of extracardiac findings detected in CTA.

RESULTS

Overall extracardiac findings were found in 1,177 patients (30.2%; 95%CI, 28.8-31.7%). 94 patients (2.4%; 95%CI, 2.0-2.9%) had extracardiac findings with a recommendation for follow-up, sixteen patients (0.4%; 95%CI, 0.3-0.7%) had incidental urgent, and another three patients (0.1%; 95%CI, 0.1-0.2%) had incidental malignant extracardiac findings. 185 of 2,330 symptomatic patients (7.9%; 95%CI, 6.9-9.1%) revealed extracardiac findings potentially explaining chest pain after exclusion of significant CAD. The number of extracardiac findings increased significantly with patient age (p < 0.001) and the cumulative experience of the CT reader (p < 0.001).

CONCLUSION

30.2% of patients undergoing CTA for exclusion of CAD had ECF, and 7.9% of symptomatic patients without significant CAD on their examination had findings that could potentially explain their symptoms.

KEY POINTS

• Of patients undergoing CTA, 2.8% have relevant incidental extracardiac findings. • CTA could identify the differential diagnosis of chest pain when excluding significant CAD. • Patient age and reader's professional experience influence the number of detected ECFs.

Prevalence of non-cardiovascular findings on CT angiography in children with congenital heart disease

BACKGROUND

CT angiography is gaining broader acceptance in the evaluation of children with known or suspected congenital heart disease. These studies include non-cardiovascular structures such as the mediastinum, lung parenchyma and upper abdominal organs. It is important to inspect all these structures for potential abnormalities that might be clinically important and, in some cases, may impact care plans.

OBJECTIVE

To determine the prevalence of non-cardiovascular findings in CT angiography of children with congenital heart disease.

MATERIALS AND METHODS

During 28 months, 300 consecutive children (170 males; mean age: 7.1 years, age range: 6 h-26 years), referred from a tertiary pediatric cardiology center, underwent clinically indicated CT angiography to evaluate known or suspected congenital heart disease. Slightly more than half (n = 169) of the patients were postoperative or post-intervention. Examinations were retrospectively reviewed, and non-cardiovascular findings were recorded and tabulated by organ system, congenital heart disease and operative procedure in conjunction with outcomes from medical charts.

RESULTS

Non-cardiovascular findings were identified in 83% (n = 250 / 300) of the studies for a total of 857 findings. In 221 patients (n = 73.7% of 300) a total of 813 non-cardiovascular findings were clinically significant, while in 9.7% (n = 29 / 300) of patients, 5.1% (n = 44 / 857) of the findings were nonsignificant. In 38.3% (n = 115 / 300) of patients with significant non-cardiovascular pathology, the findings were unexpected and directly impacted patient care plans. Commonly involved organs with non-cardiovascular findings were the lungs with 280 non-cardiovascular findings in 176 / 300 (58.7%) of patients, the airway with 139 non-cardiovascular findings in 103 / 300 (34.3%) of patients and the liver with 108 non-cardiovascular findings in 72 / 300 (24.0%) of patients. Syndromic associations were noted in 22% (n = 66 / 300) of the patients.

CONCLUSION

Non-cardiovascular findings are common in children with congenital heart disease who undergo CT angiography. Based upon our study population, if a child with congenital heart disease has a CT angiography, five out of six will have non-cardiovascular findings, while nearly three out of four (73.7%; 221 / 300) will have significant non-cardiovascular findings. Close attention to the non-cardiovascular structures in children with congenital heart disease presenting for a CT angiography is recommended as in nearly 40% of these children, findings were unexpected and directly altered patient care.

Prognostic value of extracardiac incidental findings on attenuation correction cardiac computed tomography

BACKGROUND

Attenuation corrected computed tomography (CTAC) is often performed to improve the specificity of single-photon emission tomography imaging. Extracardiac incidental findings are frequently observed. It is unclear whether these findings have any prognostic value.

METHODS

Consecutive patients (n = 1139) at a tertiary care center were retrospectively evaluated for incidental findings on CTAC. Clinically significant incidental findings were defined as findings warranting physician follow-up. Information regarding subsequent resource utilization was obtained by chart review. Cox proportional hazard model adjusted for demographic and clinical variables was used to evaluate association of these incidental findings with all-cause and cancer-specific mortality.

RESULTS

A total of 135 (12%) patients with incidental findings were identified, 83 of whom (68%) were newly diagnosed. Lung nodules were the most common finding, present in 92 (68%) patients. Over a median follow-up of 468 days, incidental findings were not significantly associated with increased risk of all-cause mortality (HR 1.34; 95% CI 0.77-2.33, P = 0.29) but was significantly associated with cancer-specific mortality (HR 3.21; 95% CI 1.26-8.14, P = 0.01). This association remained statistically significant when the analysis was limited to newly diagnosed incidental findings. Among patients with incidental findings, follow-up radiographic studies were conducted in 87%, and invasive procedures performed in 32%. Physician office-based follow-up of these findings occurred in 42% of patients and incidental finding-related hospitalization occurred in 14%.

CONCLUSIONS

This study shows that incidental findings are common and were associated with all-cause and cancer-specific mortality but only the later remained statistically significant after multivariable adjustment.

Detection of Cardiac Incidental Findings on Routine Chest CT: The Impact of Dedicated Training in Cardiac Imaging

PURPOSE

Routine chest CT and cardiac CT angiography (CTA) both image the heart, albeit with different precision and intent. The aim of this study was to evaluate the diagnostic ability of radiologists with different levels of cardiac training to identify cardiac findings on chest CT without electrocardiographic gating compared with a reference standard of electrocardiographically gated cardiac CTA.

METHODS

Electrocardiographically gated cardiac CT angiographic studies performed between January 2005 to January 2010 in patients with routine chest CT within six months were retrospectively identified. Fourteen radiologists at four stages of training (stage 1, residents with no cardiac training [n = 4]; stage 2, residents who had completed at least one dedicated rotation of cardiac imaging [n = 3]; stage 3, radiologists without cardiac training [n = 3]; and stage 4, radiologists with formal cardiac fellowship training [n = 4]) performed blinded, anonymized cardiac readings of chest CT images. Findings were categorized (coronary arterial, noncoronary vessel, cardiac chamber, myocardial, pericardial, and valve findings) with cardiac CTA as a reference standard.

RESULTS

Overall, 140 cardiac CT angiographic findings were reported in 63 of 77 patients. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of nongated CTA were 43.6%, 96.8%, 83.0%, 81.6%, and 81.8%, respectively, for all readers. Increasing training was associated with higher sensitivity (30.3%, 35.7%, 45.7%, and 61.2% from stages 1 to 4) but similar specificity (96.4%, 96.7%, 96.3%, and 97.6% from stages 1 to 4). Frequently missed findings categories were coronary arterial, myocardial, and cardiac chamber findings.

CONCLUSIONS

Increasing cardiac imaging training correlates with increased sensitivity and stable specificity to detect cardiac findings on routine chest CT without electrocardiographic gating. Cardiac findings should be noted on chest CT when observed, and cardiac training should be encouraged.

Incidental findings on cardiac computed tomography in incident hemodialysis patients: the predictors of arrhythmic and cardiovascular events in end-stage renal disease (PACE) study

BACKGROUND

This is the first study that has examined non-cardiac incidental findings in research cardiac computed tomography (CT) of hemodialysis patients and their relationship with patient characteristics.

METHODS

We performed a cross-sectional analysis in the Predictors of Arrhythmic and Cardiovascular Events in End-Stage Renal Disease (PACE) study, a prospective cohort study on incident hemodialysis patients. Non-cardiac structures in the cardiac CT scan were reviewed and evaluated. The type and frequencies of non-cardiac incidental CT findings were summarized. Univariate and multivariate logistic regression were performed to analyze the associations between gender, older age, obesity, history of cardiovascular disease (CVD), smoking status, history of chronic pulmonary disease and history of cancer with presence of any incidental CT findings and, separately, pulmonary nodules.

RESULTS

Among the 260 participants, a total of 229 non-cardiac incidental findings were observed in 145 participants (55.8% of all participants). Of these findings, pulmonary nodules were the most common incidental finding (24.2% of all findings), and 41.3% of them requiring further follow-up imaging per radiology recommendation. Vascular and gastrointestinal findings occurred in 11.8% and 15.3% of participants, respectively. Participants 65 years or older had a higher odds of any incidental findings (Odds Ratio (OR) =2.55; 95% Confidence Intervals (CI) 1.30, 4.99) and pulmonary nodules (OR=4.80; 95% CI 2.51, 9.18). Prior history of CVD was independently and significantly associated with any incidental findings (OR=2.00; 95% CI 1.19, 3.40); but not with the presence of pulmonary nodules.

CONCLUSIONS

We demonstrate that the prevalence of incidental findings by cardiac CT scanning is extremely high among patients on hemodialysis. Further investigations to follow-up on the high occurrence of incidental findings during our research study and potentially clinical studies raises important practical, ethical and medico-legal issues that need to be carefully considered in research projects using imaging studies.

Cross-sectional cardiac imaging: prevalence and significance of extracardiac findings

Cardiovascular computed tomography and magnetic resonance imaging are being increasingly performed, and both cardiologists and radiologists may take part in reporting. There is debate over the need for dual reporting or the assessment of noncardiac findings. This review highlights the prevalence and significance of noncardiac findings in such investigations and should serve as a warning to include assessment of the entire visualized chest.

Clinical evaluation of the computed tomography attenuation correction map for myocardial perfusion imaging: the potential for incidental pathology detection

The benefits of hybrid imaging in nuclear medicine have been proven to increase the diagnostic accuracy and sensitivity of many procedures by localizing or characterizing lesions or by correcting emission data to more accurately represent radiopharmaceutical distribution. Single-photon emission computed tomography/computed tomography (SPECT/CT) has a significant role in the diagnosis and follow-up of ischaemic heart disease with attenuation correction data being obtained on an integrated CT scanner. Initially, the CT component of hybrid SPECT/CT systems was what could be described as low specification utilizing fixed output parameters. As technology has progressed, the CT component of newer systems has specifications that are identical to that of stand-alone diagnostic systems. Irrespective of the type of scanner used, the computed tomography attenuation correction (CTAC) for myocardial perfusion imaging produces low-quality, limited-range CT images of the chest that include the mediastinum, lung fields and surrounding soft tissues. The diagnostic potential of this data set is unclear; yet, examples exist whereby significant pathology can be identified and investigated further. Despite guidance from a number of professional bodies suggesting that evaluation of the resulting images for every medical exposure be carried out, there is no indication as to whether this should include the evaluation of CTAC images. This review aims to initiate discussion by examining the ethical, legal, financial and practical issues (e.g. CT specification and image quality) surrounding the clinical evaluation of the CTAC for myocardial perfusion imaging images. Reference to discussions that have taken place, and continue to take place, in other modalities, current European and UK legislations, and guidelines and research in the field will be made.

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 meta-regression 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 which may improve the interpretability and comparability of future research.

Clinical demand for chest/abdomen/pelvis anatomy following thoracic or lumbar spine CT

The purpose of this study is to determine how often CT is repeated to obtain chest/abdomen/pelvis data outside the reconstructed field of view (FOV) on a prior spine CT. Radiology records of 1,239 consecutive thoracic and lumbar spine CT exams of 1,025 patients from January 1, 2006 to December 31, 2008 were retrospectively reviewed to identify patients who subsequently had CT studies of the chest, abdomen, and/or pelvis. The CT data were also evaluated for contrast enhancement, slice thickness, radiation dose, and reason for subsequent CT exam. Over 3 years, 290 of the 1,239 (24%) spine CT exams were followed by CT of the same anatomic region to evaluate extraspinal anatomy. The use or nonuse of contrast in these follow-up studies was the same as the preceding spine study in 91 cases, which were repeated on the same day (n = 37), within 7 days (n = 19), within 8-30 days (n = 15), or after 30 days (n = 20). Fourteen of 25 (56%) T spine CTs and 34 of 52 (65%) L spine CTs without contrast were followed by a chest CT or abdomen/pelvis CT without contrast within 7 days, respectively. Among 31 pediatric exams, 6 of 31 (19%) spine CTs were followed by a CT of the same anatomic region, all within 7 days. Reconstructing full FOV images of spine CT scans in addition to the standard coned down spine FOV may reduce redundant CT imaging and radiation dose.

Incidental extracardiac findings in cardiac computed tomography performed before radiofrequency ablation of atrial fibrillation

BACKGROUND

Radiofrequency ablation has became a validated therapeutic technique for symptomatic drug refractory atrial fibrillation (AF). Cardiac computed tomography (CT) is used to evaluate left atrial (LA) anatomy in order to improve AF ablation. The analysis of noncardiac structures during cardiac CT may identify clinically significant incidental findings (IFs). The objective of this study was to determine the prevalence of IF in patients undergoing AF catheter ablation.

METHODS

Between February 2008 and March 2010, all patients planned for a first procedure of AF or LA tachycardia (LAT) ablation underwent a cardiac CT scan and were retrospectively included in this study. Extracardiac IFs were considered to be present if an abnormality was identified without previous clinical suspicion or known disease.

RESULTS

Two hundred and fifty patients (55.2 ± 9.6 years of age, 82.4% men) were enrolled (133 paroxysmal, 43 persistent, 58 permanent AF, and 16 LAT). Fifty-eight patients (23.2%) had a total of 76 IFs. Patients with IF were significantly older (59.5 ± 8.2 vs 53.8 ± 9.7 years old, P < 0.001). No relationship existed between the type of arrhythmia and IF existence. The majority of IFs were pulmonary (50%), with 15.8% of pulmonary emphysema. Two cases of lung cancer and of pulmonary fibrosis, 15 mediastinal adenopathies, and three congenital coronary arteries anomalies were found.

CONCLUSIONS

Cardiac CT scan is a useful tool to evaluate LA morphology before AF ablation. However, as a considerable prevalence of IF was found in our study, extracardiac structures should be routinely analyzed to detect unknown conditions, which could require specific management.

Lung cancer detected at cardiac CT: prevalence, clinicoradiologic features, and importance of full-field-of-view images

PURPOSE

To retrospectively evaluate the prevalence and clinicoradiologic features of lung cancer detected at cardiac computed tomography (CT) and compare the detection rates at different field-of-view (FOV) settings.

MATERIALS AND METHODS

The institutional review board approved this retrospective study and waived the requirement for patient consent. Patients with lung cancer initially detected at cardiac CT were identified by means of a retrospective search of a lung cancer registry patient database between January 2004 and December 2007. Patients known to have lung cancer at the time of cardiac CT were excluded. The prevalence and clinical and radiologic features of lung cancer were evaluated. The rates of lung cancer detection at three FOVs-limited and full FOV at cardiac scanning and full FOV at thoracic scanning-were compared by using McNemar testing.

RESULTS

The prevalence of lung cancer detected at CT was 0.31% (36 of 11654 patients, 16 [44%] never smokers) and was higher in patients suspected or known to have coronary artery disease (0.43% [24 of 5615 patients]) than in asymptomatic screening-examined patients (0.20% [12 of 5924 patients]) (P = .0457). Adenocarcinoma was the most common (in 31 [86%] of 36 patients) histologic subtype. Of 34 non-small cell lung cancers, 23 (68%)-including 16 stage IA cancers-were resectable. Four (11%) and 19 (53%) of the 36 CT-depicted cancers were visible in limited and full FOV at cardiac scanning, respectively, and 17 (47%) were visible in full FOV at thoracic scanning only.

CONCLUSION

The prevalence of lung cancer at cardiac CT was 0.31%; and 68% of these malignancies were at a resectable stage. Use of a limited FOV at cardiac scanning led to a large majority (89% [32 of 36 cancers]) of the lung cancers detected at full thoracic scanning being missed; thus, inclusion of the entire chest at cardiac CT is advisable.

Extracardiac findings in cardiac computed tomographic angiography in patients at low to intermediate risk for coronary artery disease

PURPOSE

To evaluate the prevalence, clinical significance, interobserver agreement, and follow-up of extracardiac findings on coronary computed tomographic angiography (CTA).

METHODS

A prospectively recruited cohort of 80 patients at low to intermediate risk of having coronary artery disease underwent CTA with field of view imaging from lung apices to upper abdomen. Two staff radiologists read each scan independently. Scans read by reader no. 1 were read as part of routine clinical practice, and the findings were subsequently reclassified to potentially significant, as defined by requiring clinical or radiologic follow-up, and insignificant by a separate observer, whereas reader no. 2 retrospectively read and autonomously classified the findings as potentially significant or insignificant.

RESULTS

Reader no. 1 found 7 potentially significant findings in 7 patients and 33 insignificant findings in 29 patients. Reader no. 2 found 10 potentially significant findings in 10 patients and 59 insignificant findings in 42 patients. Inter-rater agreement was moderate (kappa = 0.49; 95% confidence interval, 0.31-0.67) for the presence vs the absence of extracardiac findings and moderate (kappa = 0.52; 95% confidence interval, 0.15-0.89) for the presence of potentially significant extracardiac findings. The most common potentially significant finding was possibly malignant lung nodule (n = 6 [reader 1], 4 [reader 2]). Four patients with potentially significant findings received follow-up imaging, and 1 patient underwent biopsy, which was complicated by pneumothorax. No diagnoses of malignancy were made.

CONCLUSIONS

Extracardiac findings are frequent and moderately reproducible, however, in this study, not associated with clinical benefit. Large prospective studies are required to establish whether reporting of extracardiac findings is associated with improved patient outcomes.

Incidental non-cardiac findings of a coronary angiography with a 128-slice multi-detector CT scanner: should we only concentrate on the heart?

Objective

To evaluate the spectrum, prevalence, and significance of incidental non-cardiac findings (INCF) in patients referred for a non-invasive coronary angiography using a 128-slice multi-detector CT (MDCT).

Materials and Methods

The study subjects included 1,044 patients; 774 males (mean age, 59.9 years) and 270 females (mean age, 63 years), referred for a coronary CT angiography on a 128-slice MDCT scanner. The scans were acquired from the level of the carina to just below the diaphragm. To evaluate INCFs, images were reconstructed with a large field of view (> 300 mm) covering the entire thorax. Images were reviewed in the axial, coronal, and sagittal planes, using the mediastinal, lung, and bone windows. The INCFs were classified as severe, indeterminate, and mild, based on their clinical importance, and as thoracic or abdominal based on their locations.

Results

Incidental non-cardiac findings were detected in 56% of patients (588 of 1,044), including 435 males (mean age, 65.6 years) and 153 females (mean age, 67.9 years). A total of 729 INCFs were observed: 459 (63%) mild (58% thoracic, 43% abdominal), 96 (13%) indeterminate (95% thoracic, 5% abdominal), and 174 (24%) severe (87% thoracic, 13% abdominal). The prevalence of severe INCFs was 15%. Two severe INCFs were histologically verified as lung cancers.

Conclusion

The 128-slice MDCT coronary angiography, in addition to cardiac imaging, can provide important information on the pathology of the chest and upper abdomen. The presence of severe INCFs is not rare, especially in the thorax. Therefore, all organs in the scan should be thoroughly evaluated in daily clinical practice.

Cardiac computed tomographic angiography: evaluation of non-cardiac structures

Cardiac computed tomography is a promising new technology for non-invasive evaluation of the coronary arteries. As CT is inherently a high resolution volumetric imaging modality, data from structures other than the heart can be accessed in studies performed primarily for cardiac indications. Current generation scanners can easily detect abnormalities such as pulmonary emboli and aortic dissection on routine coronary CT angiograms. Many other abnormalities such as small pulmonary nodules can also be detected. While major abnormalities like aortic dissection are of obvious clinical importance, detection of incidental abnormalities such as small pulmonary nodules less than 4 mm in diameter has not yet been shown to positively affect patient outcomes, and may lead to unnecessary testing. Recommendations for image reconstruction and training in interpretation of incidental findings continue to evolve, but most agree that coronary CT angiography should be focused primarily on the coronary arteries.

Maximizing dose reductions with cardiac CT

Multidetector computed tomography has come a long way in a short time, quickly becoming a standard tool in the cardiac imaging armamentarium. The promise of plaque imaging, combined with both anatomical visualization and stenosis detection, has made this a preferred first line test of many cardiologists and radiologists. This test is well suited to rule out coronary artery disease (obstruction) and still diagnosing subclinical plaque, with may be a good target for anti-atherosclerotic therapies. There has been recent criticism against CT imaging, and cardiac CT specifically, due to the high radiation doses that being employed. New advances have allowed for dramatic dose reductions. These include more routinely performed methods such as dose modulation, and newer methods such as prospective gating or minimizing the field of view. This paper will review the different applications to reduce cardiac CT radiation doses to nominal levels, potentially expanding the applications of cardiac CT by removing one of the biggest barriers.