The dilemma of incidental findings on cardiac computed tomography

Evolution of Stress Echocardiogram in the Era of CT Angiography

The ideal diagnostic modality for acute chest pain is a highly debated topic in the cardiovascular community. With the rapid rise of coronary computed tomography angiography (CTA) and the fall of functional testing, stress echocardiography (SE) is at a delicate crossroads. Though there are many advantages of coronary CTA, it is not without its flaws. The exact realm of SE needs to be clearly defined, as well as which patients need diagnostic testing. The emergence of additional parameters will propel the evolution of modern SE. In this review article, we explore the role of SE, guidelines, comparison of SE versus CTA, and additional parameters in the coronary CTA era.

Creating an Incidental Pulmonary Nodule Safety-Net Program

Pulmonary nodules are a frequent, incidental finding on CT scans, ranging from up to 8.4% on abdominal scans and up to 48% on CT angiograms. Incidental findings are sometimes disregarded or overshadowed by critical situations and may not be disclosed or documented on discharge. The costs and risks associated with incidental findings are not insignificant, including the risk of a delayed diagnosis of lung cancer. A medical center commitment to prevent overlooked incidental pulmonary nodules led to the development of an incidental pulmonary nodule program. The program, led by an advanced practice nurse, established processes to identify patients with incidental lung nodules on CT scans and developed criteria for further follow-up with the primary care provider and the patient. Improvements with consistent use of Fleischner guidelines in scan reports by radiologists and increased ownership in informing patients of incidental nodules by ED and trauma providers have occurred. As the frequency of chest CT imaging is increasing, the number of incidental nodules identified will also increase. A lung nodule surveillance process would greatly benefit every lung nodule clinic or hospital system for management of pulmonary nodules.

Clinical significance of incidental findings on coronary CT angiography: Insights from a randomized controlled trial

BACKGROUND

The effect of incidental findings from coronary computed tomography angiography (CCTA) on management has not been rigorously investigated. This study uses a control group to explore this relationship.

METHODS

Analysis of data from a randomized controlled trial of acute chest pain patients admitted to telemetry was performed. Patients were randomized to undergo either CCTA (n = 200) or radionuclide myocardial perfusion imaging (MPI) (n = 200). Incidental findings were determined from imaging reports. Records were reviewed to determine subsequent management and imaging during and after hospitalization. Comparisons were performed using Fischer's exact tests.

RESULTS

386 incidental findings were found among 187 CCTA studies. No extra-cardiac incidental findings were noted in the MPI arm, which served as an effective control group. There were significantly more non-coronary medical workups during admission in the CCTA group compared to the MPI group [20% (39) vs. 12% (23), P = 0.038]. CCTA patients underwent significantly more resting echocardiography during the inpatient workup compared to the MPI group [38% (75) vs. 18% (55), P = 0.042]. CCTA patients underwent significantly more non-contrast chest CT exams in the year following admission compared to MPI patients [14% (27) vs. 7% (13) P = 0.029].

CONCLUSIONS

Incidental findings on inpatient CCTAs performed for chest pain have a significant impact on treatment and imaging during and following hospital admission.

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.

Prevalence and consequences of noncardiac incidental findings on preprocedural imaging in the workup for transcatheter aortic valve implantation, renal sympathetic denervation, or MitraClip implantation

BACKGROUND

Dedicated data on the prevalence of incidental findings (IF) stratified according to overall clinical relevance and their subsequent correlation to outcome are lacking. The aim of the present study was to describe the prevalence and consequences of noncardiac IF on computed tomography or magnetic resonance imaging in the workup for interventional cardiovascular procedures.

METHODS

A total of 916 patients underwent preprocedural computed tomography or magnetic resonance imaging in the workup for transcatheter aortic valve implantation (TAVI), renal sympathetic denervation (RDN), or MitraClip implantation.

RESULTS

IF were found in 395 of 916 patients (43.1%), with an average of 1.8 IF per patient. Classifying the IF resulted in 155 patients with minor, 171 patients with moderate, and 69 patients with major IF. The intended procedure was delayed or canceled in only 15 of 916 (1.6%) of the patients because of the presence of potential malignant IF. In patients that did undergo the intended procedure (n = 774), the presence of a moderate or major IF (23.8%) did not impact 1-year mortality compared to no or minor IF (adjusted HR 0.90, 95% CI 0.56-1.44, P value = .65). These findings were consistent among patients referred for TAVI, RDN, or MitraClip.

CONCLUSIONS

IF are frequent in patients referred for cardiovascular procedures. IF did not result in a delay or cancellation of the intended procedure in the vast majority of cases, irrespective of their clinical relevance. The presence of a major or moderate IF did not significantly impact 1-year mortality.

Incidental extraspinal findings in the lumbar spine during magnetic resonance imaging of intervertebral discs

Purpose

To calculate the frequencies of incidental extraspinal findings and incidentally detected congenital anomalies or anatomical differences in the lumbar spine on magnetic resonance imaging (MRI) scans of intervertebral discs.

Materials and methods

A total of 379 lumbar spine MRI cases were prospectively investigated in the period spanning from August 2016 to January 2018. Both 1.5 and 0.35 Tesla MRI units (Toshiba and Siemens Medical Systems) were used to examine patients with clinically suspected intervertebral disc abnormalities at three MRI diagnostic centers in Khartoum State, Sudan.

Results

Of the 379(100%) patients, 90(23.7%) patients were presented with incidental findings. Among the incidental findings, 39(10.3%) were renal cysts, 10(2.6%) were retroverted uteri, 5(1.3%) were Nabothian cysts, 4(1.1%) were ovarian cysts, 10(2.6%) were uterine fibroids, 3(0.8%) were endometrial thickening, 11(2.9%) were indicative of hydronephrosis, 4(1.1%) were uncovered prostatic enlargement, 2(0.5%) were atrophic kidney, and 1(0.3%) each was of an ectopic kidney and bladder wall thickening, respectively.

Conclusions

A high percentage of extraspinal pathological findings were detected during MRI lumbar spine scans of intervertebral discs. Thus, it is important to be aware of the high percentage of patients who undergo further evaluation given the presence of unexpected findings, but for whom clinical confirmation of these abnormalities is not obtained.

Thoracic Incidental Findings in Preoperative Computed Tomography Evaluation for Transcatheter Aortic Valve Implantation (TAVI)

BACKGROUND

Many older patients with aortic stenosis are excluded from surgical intervention due to multiple comorbidities. For these patients, transcatheter aortic valve implantation (TAVI) is a viable treatment alternative. Cardiothoracic computed tomography (CT) provides detailed anatomic assessment of the aortic root structures for patient selection, preprocedural planning, and intraoperative decision-making; however, nonaortic incidental findings are frequently detected. The prevalence and clinical significance of these findings have not been well described.

MATERIALS AND METHODS

This retrospective study examined incidental findings in 209 consecutive patients (96 women and 113 men; mean age, 70 y) with aortic stenosis undergoing preoperative cardiothoracic CT evaluation for TAVI during a 3-year period. Incidental findings were recorded, and medical records were reviewed for follow-up diagnostic examinations.

RESULTS

Incidental findings, both significant and nonsignificant, were observed in 85.6% of patients (179/209). Noncalcified pulmonary nodules were the most common incidental finding occurring in 59/209 (28.2%) patients, followed by pleural effusion and emphysema both of which occurred in 34/209 (16.3%) patients, respectively.

CONCLUSIONS

Cardiothoracic CT obtained for evaluation before TAVI has a high frequency of incidental findings.

Extraspinal Incidental Findings on Routine MRI of Lumbar Spine: Prevalence and Reporting Rates in 1278 Patients

Objective

The aim of the present study was to determine the prevalence and reporting rate of incidental findings (IF) in adult outpatients undergoing lumbar magnetic resonance imaging (MRI).

Materials and Methods

Re-evaluation of a total of 1278 lumbar MRI images (collected from patients with a mean age of 50.5 years, range 16-91 years) captured between August 2010-August 2011 was done by a neuroradiologist and a musculoskeletal radiologist. IFs were classified according to organ or system (liver, gallbladder, kidney, bladder, uterus, ovary, lymph node, intestine and aorta). The rate of reporting of a range of IF was examined. The outcome of each patient's treatment was evaluated based on review of hospital records and by telephone interviews.

Results

A total of 253 IFs were found in 241 patients (18.8% of 1278). Among these, clinically significant IFs (n = 34) included: 2 renal masses (0.15%), 2 aortic aneurysms (0.15%), 2 cases of hydronephrosis (0.15%), 11 adrenal masses (0.86%), 7 lymphadenopathies (0.55%), 6 cases of endometrial or cervical thickening (0.47%), 1 liver hemangioma (0.08%), 1 pelvic fluid (0.08%) and 2 ovarian dermoid cysts (0.15%). Overall, 28% (71/253) of IFs were included in the clinical reports, while clinically significant findings were reported in 41% (14/34) of cases.

Conclusion

Extraspinal IFs are commonly detected during a routine lumbar MRI, and many of these findings are not clinically significant. However, IFs including clinically important findings are occasionally omitted from formal radiological reports.

The diagnosis of CAD in women: addressing the unmet need - a report from the national expert roundtable meeting

A multistakeholder panel comprising experts in the fields of clinical cardiology, medical technology innovation, women's health research and policy analysis, personalized medicine, payers (including self-insured employers), patient advocacy, and health economics was convened at the Heart House in Washington, DC. The following points emerged as key concepts: (1) Diagnostic challenges in the evaluation of women with symptoms suggestive of obstructive coronary artery disease (CAD) result from: (a) presentation with atypical symptoms and lower pretest probability of disease compared to men, (b) fatty tissue and breast tissue attenuation on cardiac imaging leading to false positive findings, and (c) the presence of microvascular CAD. (2) Diagnostic challenges lead to both over-testing of low-risk women and under-testing of high-risk women. (3) Efforts should be directed toward increasing clinician, clinical professional society, and consumer awareness and understanding of sex-specific differences between men and women in the pathophysiology of CAD. (4) Multiple health care stakeholders should be made aware of new advances in genomic approaches to address the challenges of diagnosing obstructive CAD; specifically, the Corus CAD gene expression test, which was shown to have high sensitivity and negative predictive value in a recent clinical trial. As such, it has promise as a tool to help clinicians to rule out obstructive CAD as a cause of a patient's symptoms. (Population Health Management 2015;18:86-92).

Using the coronary artery calcium score to guide statin therapy: a cost-effectiveness analysis

BACKGROUND

The coronary artery calcium (CAC) score predicts future coronary heart disease (CHD) events and could be used to guide primary prevention interventions, but CAC measurement has costs and exposes patients to low-dose radiation.

METHODS AND RESULTS

We estimated the cost-effectiveness of measuring CAC and prescribing statin therapy based on the resulting score under a range of assumptions using an established model enhanced with CAC distribution and risk estimates from the Multi-Ethnic Study of Atherosclerosis. Ten years of statin treatment for 10,000 55-year-old women with high cholesterol (10-year CHD risk, 7.5%) was projected to prevent 32 myocardial infarctions, cause 70 cases of statin-induced myopathy, and add 1108 years to total life expectancy. Measuring CAC and targeting statin treatment to the 2500 women with CAC>0 would provide 45% of the benefit (+501 life-years), but CAC measurement would cost $2.25 million and cause 9 radiation-induced cancers. Treat all was preferable to CAC screening in this scenario and across a broad range of other scenarios (CHD risk, 2.5%-15%) when statin assumptions were favorable ($0.13 per pill and no quality of life penalty). When statin assumptions were less favorable ($1.00 per pill and disutility=0.00384), CAC screening with statin treatment for persons with CAC>0 was cost-effective (<$50 000 per quality-adjusted life-year) in this scenario, in 55-year-old men with CHD risk 7.5%, and in other intermediate risk scenarios (CHD risk, 5%-10%). Our results were critically sensitive to statin cost and disutility and relatively robust to other assumptions. Alternate CAC treatment thresholds (>100 or >300) were generally not cost-effective.

CONCLUSIONS

CAC testing in intermediate risk patients can be cost-effective but only if statins are costly or significantly affect quality of life.

Next generation sequencing in psychiatric research: what study participants need to know about research findings

The use of next generation sequencing (NGS) technologies in psychiatric genetics research and its potential to generate individual research results will likely have far reaching implications for predictive and diagnostic practices. The extent of this impact may not be easily understood by psychiatric research participants during the consent process. The traditional consent process for studies involving human subjects does not address critical issues specific to NGS research, such as the return of results. We examined which type of research findings should be communicated, how this information should be conveyed during the consent process and what guidance is required by researchers and IRBs to help psychiatric research participants understand the peculiarities, the limits and the impact of NGS. Strong standards are needed to ensure appropriate use of data generated by NGS, to meet participants' expectations and needs, and to clarify researchers' duties regarding the disclosure of data and their subsequent management. In the short term, researchers and IRBs need to be proactive in revising current consent processes that deal with the disclosure of research findings.

The PROgnostic Value of unrequested Information in Diagnostic Imaging (PROVIDI) Study: rationale and design

We describe the rationale for a new study examining the prognostic value of unrequested findings in diagnostic imaging. The deployment of more advanced imaging modalities in routine care means that such findings are being detected with increasing frequency. However, as the prognostic significance of many types of unrequested findings is unknown, the optimal response to such findings remains uncertain and in many cases an overly defensive approach is adopted, to the detriment of patient-care. Additionally, novel and promising image findings that are newly available on many routine scans cannot be used to improve patient care until their prognostic value is properly determined. The PROVIDI study seeks to address these issues using an innovative multi-center case-cohort study design. PROVIDI is to consist of a series of studies investigating specific, selected disease entities and clusters. Computed Tomography images from the participating hospitals are reviewed for unrequested findings. Subsequently, this data is pooled with outcome data from a central population registry. Study populations consist of patients with endpoints relevant to the (group of) disease(s) under study along with a random control sample from the cohort. This innovative design allows PROVIDI to evaluate selected unrequested image findings for their true prognostic value in a series of manageable studies. By incorporating unrequested image findings and outcomes data relevant to patients, truly meaningful conclusions about the prognostic value of unrequested and emerging image findings can be reached and used to improve patient-care.

Extracardiac findings on coronary CT angiograms: Limited versus complete image review

OBJECTIVE

Cardiac CT often reveals findings outside the heart and great vessels. A few cardiologists have suggested that the field of interpretation be restricted to avoid false-positive diagnoses. Radiologists generally favor a comprehensive review to avoid false-negative findings. The purpose of this study was to examine this tradeoff by comparing broad and focused approaches with viewing coronary CT angiograms.

MATERIALS AND METHODS

Outpatient coronary CT angiography was performed on consecutively registered patients. In the broad approach to review, both the large field-of-view and small field-of-view image sets, including lung windows, were evaluated. In the focused approach, attention was centered on the heart, great vessels, and immediately adjacent structures and did not include lung windows. Each finding was classified as necessitating immediate therapy, timely additional workup, longer-term follow-up, or no action.

RESULTS

Among 6,920 patients, 1,642 (23.7%) had one or more extracardiac findings for a total of 1,901 findings in the broad viewing scheme. Of the 6,920 patients, 16.2% had a finding necessitating therapy, workup, or follow-up. In the focused viewing scheme, 90.9% of the findings necessitating therapy, 64.1% necessitating workup, and 51.2% necessitating follow-up were missed. Use of the focused approach resulted in fewer false-positive diagnoses, but five malignant tumors of the breast, 88 lung infiltrates, 43 cases of adenopathy, two cases of polycystic kidney disease, one breast abscess, and one case of splenic flexure diverticulitis were missed.

CONCLUSION

Almost one fourth of all patients who underwent diagnostic coronary CT angiography in this study had extracardiac findings. Several serious diagnoses were missed with the limited viewing approach, but use of the broad viewing approach led to more workup and follow-up imaging.