2015 ACR/ACC/AHA/AATS/ACEP/ASNC/NASCI/SAEM/SCCT/SCMR/SCPC/SNMMI/STR/STS Appropriate Utilization of Cardiovascular Imaging in Emergency Department Patients With Chest Pain: A Joint Document of the American College of Radiology Appropriateness Criteria Committee and the American College of Cardiology Appropriate Use Criteria Task Force

CT Coronary Angiography: Technical Approach and Atherosclerotic Plaque Characterization

Coronary computed tomography angiography (CCTA) currently represents a robust imaging technique for the detection, quantification and characterization of coronary atherosclerosis. However, CCTA remains a challenging task requiring both high spatial and temporal resolution to provide motion-free images of the coronary arteries. Several CCTA features, such as low attenuation, positive remodeling, spotty calcification, napkin-ring and high pericoronary fat attenuation index have been proved as associated to high-risk plaques. This review aims to explore the role of CCTA in the characterization of high-risk atherosclerotic plaque and the recent advancements in CCTA technologies with a focus on radiomics plaque analysis.

The Role and Advantages of Cardiac Magnetic Resonance in the Diagnosis of Myocardial Ischemia

Ischemic heart disease continues to be the leading cause of death and disability worldwide. For the diagnosis of ischemic heart disease, some form of cardiac stress test involving exercise or pharmacological stimulation continues to play an important role, despite advances within modalities like computer tomography for the noninvasive detection and characterization of epicardial coronary lesions. Among noninvasive stress imaging tests, cardiac magnetic resonance (CMR) combines several capabilities that are highly relevant for the diagnosis of ischemic heart disease: assessment of wall motion abnormalities, myocardial perfusion imaging, and depiction of replacement and interstitial fibrosis markers by late gadolinium enhancement techniques and T1 mapping. On top of these qualities, CMR is also well tolerated and safe in most clinical scenarios, including in the presence of cardiovascular implantable devices, while in the presence of renal disease, gadolinium-based contrast should only be used according to guidelines. CMR also offers outstanding viability assessment and prognostication of cardiovascular events. The last 2019 European Society of Cardiology guidelines for chronic coronary syndromes has positioned stress CMR as a class I noninvasive imaging technique for the diagnosis of coronary artery disease in symptomatic patients. In the present review, we present the current state-of-the-art assessment of myocardial ischemia by stress perfusion CMR, highlighting its advantages and current shortcomings. We discuss the safety, clinical, and cost-effectiveness aspects of gadolinium-based CMR-perfusion imaging for ischemic heart disease assessment.

Automated Classification of Atherosclerotic Radiomics Features in Coronary Computed Tomography Angiography (CCTA)

Radiomics is the process of extracting useful quantitative features of high-dimensional data that allows for automated disease classification, including atherosclerotic disease. Hence, this study aimed to quantify and extract the radiomic features from Coronary Computed Tomography Angiography (CCTA) images and to evaluate the performance of automated machine learning (AutoML) model in classifying the atherosclerotic plaques. In total, 202 patients who underwent CCTA examination at Institut Jantung Negara (IJN) between September 2020 and May 2021 were selected as they met the inclusion criteria. Three primary coronary arteries were segmented on axial sectional images, yielding a total of 606 volume of interest (VOI). Subsequently, the first order, second order, and shape order of radiomic characteristics were extracted for each VOI. Model 1, Model 2, Model 3, and Model 4 were constructed using AutoML-based Tree-Pipeline Optimization Tools (TPOT). The heatmap confusion matrix, recall (sensitivity), precision (PPV), F1 score, accuracy, receiver operating characteristic (ROC), and area under the curve (AUC) were analysed. Notably, Model 1 with the first-order features showed superior performance in classifying the normal coronary arteries (F1 score: 0.88; Inverse F1 score: 0.94), as well as in classifying the calcified (F1 score: 0.78; Inverse F1 score: 0.91) and mixed plaques (F1 score: 0.76; Inverse F1 score: 0.86). Moreover, Model 2 consisting of second-order features was proved useful, specifically in classifying the non-calcified plaques (F1 score: 0.63; Inverse F1 score: 0.92) which are a key point for prediction of cardiac events. Nevertheless, Model 3 comprising the shape-based features did not contribute to the classification of atherosclerotic plaques. Overall, TPOT shown promising capabilities in terms of finding the best pipeline and tailoring the model using CCTA-based radiomic datasets.

Role of CT and MRI in Cardiac Emergencies

Current strategies for the evaluation of patients with chest pain have significantly changed thanks to the implemented potentiality of CT and MRI. The possible fatal consequences and high malpractice costs of missed acute coronary syndromes lead to unnecessary hospital admissions every year. CT provides consistent diagnostic support, mainly in suspected coronary disease in patients with a low or intermediate pre-test risk. Moreover, it can gain information in the case of cardiac involvement in pulmonary vascular obstructive disease. MRI, on the other hand, has a leading role in the condition of myocardial damage irrespective of the underlying inflammatory or stress related etiology. This article discusses how radiology techniques (CT and MRI) can impact the diagnostic workflow of the most common cardiac and vascular pathologies that are responsible for non-traumatic chest pain admissions to the Emergency Department.

Noninvasive Imaging for Patients with COVID-19 and Acute Chest Pain

Acute chest pain is a common presentation in patients with COVID-19. Although noninvasive cardiac imaging modalities continue to be important cornerstones of management, the pandemic has brought forth difficult and unprecedented challenges in the provision of timely care while ensuring the safety of patients and providers. Clinical practice has adapted to these challenges, with several recommendations and societal guidelines emerging on the appropriate use of imaging modalities. In this review, we summarize the current evidence base on the use of noninvasive cardiac imaging modalities in COVID-19 patients with acute chest pain, with a focus on acute coronary syndromes.

Feasibility and Impact of the Combined Application of Coronary CT Angiography With the HEART Pathway in Patients With Suspected Acute Coronary Syndrome

BACKGROUND

This study examines the feasibility and utility of integrating coronary computed tomography angiography and the HEART Pathway into a novel accelerated diagnostic protocol-called HEART-CT-and assesses its impact as an optional interactive decision support tool (smart form) in the electronic health record.

METHODS

This was a retrospective observational study performed in 2 adult emergency departments (ED) among patients evaluated for suspected acute coronary syndrome. Primary outcomes included the rate of discharge from the ED following HEART-CT Smart Form use, 30-day major adverse cardiac events (MACE), and ED length of stay (LOS). Hypothesis-generating outcomes included the rate of Smart Form use by ED providers and whether adhering to the HEART-CT recommendations was associated with improved outcomes.

RESULTS

The study included 672 subjects, 78.1% of whom were discharged from the ED. HEART-CT identified 76.7% of patients with increased risk HEAR scores as safe for discharge. No patients identified as low risk by HEART-CT had MACE within 30 days. Total mean ED LOS was 4.6 hours. ED providers used the HEART-CT smart form in 19.7% of eligible patients. ED providers who followed the HEART-CT recommendations had 3.41 times higher odds of ED discharging patients with increased risk HEAR scores than nonadherent providers (95% CI, 2.20-5.27).

CONCLUSIONS

HEART-CT reclassified a large proportion of patients as safe for discharge, maintained a high sensitivity for detecting 30-day MACE, and had an acceptable ED LOS. Future studies should test the extent to which more automated clinical decision support improves provider adoption and clinical outcomes of HEART-CT.

Non-invasive Imaging in Coronary Syndromes - Recommendations of the European Association of Cardiovascular Imaging and the American Society of Echocardiography, in Collaboration with the American Society of Nuclear Cardiology, Society of Cardiovascular Computed Tomography and Society for Cardiovascular Magnetic Resonance

Coronary artery disease (CAD) is one of the major causes of mortality and morbidity worldwide, with a high socioeconomic impact.(1) Non-invasive imaging modalities play a fundamental role in the evaluation and management of patients with known or suspected CAD. Imaging end-points have served as surrogate markers in many observational studies and randomized clinical trials that evaluated the benefits of specific therapies for CAD.(2) A number of guidelines and recommendations have been published about coronary syndromes by cardiology societies and associations, but have not focused on the excellent opportunities with cardiac imaging. The recent European Society of Cardiology (ESC) 2019 guideline on chronic coronary syndromes (CCS) and 2020 guideline on acute coronary syndromes in patients presenting with non-ST-segment elevation (NSTE-ACS) highlight the importance of non-invasive imaging in the diagnosis, treatment, and risk assessment of the disease.(3)(4) The purpose of the current recommendations is to present the significant role of non-invasive imaging in coronary syndromes in more detail. These recommendations have been developed by the European Association of Cardiovascular Imaging (EACVI) and the American Society of Echocardiography (ASE), in collaboration with the American Society of Nuclear Cardiology, the Society of Cardiovascular Computed Tomography, and the Society for Cardiovascular Magnetic Resonance, all of which have approved the final document.

Cardiovascular Testing and Imaging in Pregnant Women

Cardiovascular disease is a major contributor to maternal morbidity and mortality and frequently preventable. Women with known cardiovascular disease should undergo cardiac evaluation before pregnancy. Many women with pregnancy-associated cardiac complications are not previously known to have cardiac disease. Women at high risk or who have signs or symptoms suggestive of heart failure, angina, or arrhythmias should undergo prompt evaluation. This article describes various diagnostic imaging modalities that can be used in pregnancy, including indications, strengths, and limitations.

Impact of High-Deductible Health Plans on Emergency Department Patients With Nonspecific Chest Pain and Their Subsequent Care

Supplemental Digital Content is available in the text.

Timely evaluation of acute chest pain is necessary, although most evaluations will not find significant coronary disease. With employers increasingly adopting high-deductible health plans (HDHP), how HDHPs impact subsequent care after an emergency department (ED) diagnosis of nonspecific chest pain is unclear.

Transthoracic Echocardiography: Beginner's Guide with Emphasis on Blind Spots as Identified with CT and MRI

Transthoracic echocardiography (TTE) is the primary initial imaging modality in cardiac imaging. Advantages include portability, safety, availability, and ability to assess the morphology and physiology of the heart in a noninvasive manner. Because of this, many patients who undergo advanced imaging with CT or MRI will have undergone prior TTE, particularly when cardiac CT angiography or cardiac MRI is performed. In the modern era, the increasing interconnectivity of picture archiving and communication systems (PACS) has made these images more available for comparison. Therefore, radiologists who interpret chest imaging studies should have a basic understanding of TTE, including its strengths and limitations, to make accurate comparisons and assist in rendering a diagnosis or avoiding a misdiagnosis. The authors present the standard TTE views along with multiplanar reformatted CT images for correlation. This is followed by examples of limitations of TTE, focusing on potential blind spots, which have been placed in seven categories on the basis of the structures involved: (a) pericardium (thickening, calcification, effusions, cysts, masses), (b) aorta (dissection, intramural hematoma, penetrating atherosclerotic ulcer), (c) left ventricular apex (infarcts, aneurysms, thrombus, apical hypertrophic cardiomyopathy), (d) cardiac valves (complications of native and prosthetic valves), (e) left atrial appendage (thrombus), (f) coronary arteries (origins, calcifications, fistulas, aneurysms), and (g) extracardiac structures (primary and metastatic masses). Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article . ^©RSNA, 2021.

The Impact of Implementing 24/7 Cardiac CTA Interpretation in the Emergency Department on Patient Care: Retrospective Analysis of a Single-Center Experience

OBJECTIVE. The objective of our study was to provide insight on the diagnostic validity of cardiac CTA (CCTA) to identify obstructive coronary artery disease (CAD) and patients who require urgent intervention, compared with those who require same-admission coronary catheterization (CC), and to help elucidate the necessity of a 24/7 CCTA service. MATERIALS AND METHODS. We retrospectively reviewed 658 consecutive CCTA examinations performed of emergency department (ED) patients who presented with acute chest pain from October 1, 2013, to February 28, 2018. Patients were categorized by CAD severity on CCTA. Using same-admission CC as the reference standard, we assessed CCTA's validity to identify obstructive disease using PPV, NPV, sensitivity, and specificity and CCTA's validity to identify patients who require urgent intervention. The added value of the CCTA findings of subendocardial hypoattenuation and wall motion abnormality was evaluated. CCTA examinations were categorized on the basis of the time of day when scanning was performed. RESULTS. The PPV, NPV, and sensitivity of CCTA to diagnose obstructive CAD were 0.87, 0.79, and 0.95, respectively. Nine percent of the scanned patients underwent percutaneous coronary intervention (PCI) or were referred for urgent coronary artery bypass grafting (CABG). The presence of obstructive CAD on CCTA has a PPV of 0.73 to identify patients deemed to be at higher acute coronary syndrome (ACS) risk to warrant urgent PCI or CABG. Wall motion abnormality increased the PPV to 1.0; subendocardial attenuation increased the PPV to 0.9. The NPV and sensitivity were 0.89 and 0.97, respectively. Of the CCTA examinations, 54% were performed outside regular working hours. Of the patients who received urgent interventions, 62% underwent CCTA examinations performed outside regular working hours. CONCLUSION. CCTA provides high correlation with CC, helps identify individuals with high ACS risk, and is further strengthened by functional analysis; 24/7 CCTA service is warranted.

The NSW Pathology Atlas of Variation: Part II-The Association of Variation in Emergency Department Laboratory Investigations With Outcomes for Patients Presenting With Chest Pain

STUDY OBJECTIVE

Laboratory test use varies across emergency departments (EDs), yet little is known about the effect of this variation on outcomes. The aim of this study is 2-fold: to stratify EDs into clusters based on similar test use, and to determine whether the clusters differ in patient operational outcomes among patients presenting to EDs with undifferentiated chest pain.

METHODS

We conducted a retrospective cohort study of 222,788 patients presenting with undifferentiated chest pain at 44 EDs across New South Wales, Australia, from January 2017 to September 2018. The operational outcomes measured in this study included ED length of stay, hospital admission, the Emergency Treatment Performance target, and 7- and 15-day all-cause and same-cause ED revisit rates. We performed a hierarchic cluster analysis to identify ED clusters and mixed-effects models to determine the association between the clusters and the operational outcomes.

RESULTS

Two ED clusters, moderate users (18 EDs) and high users (26 EDs), were identified. After adjustment for confounders, the median ED length of stay was greater by 15.7% (equivalent to 33.4 minutes) in high versus moderate users (95% confidence interval 6.62 to 25.52 minutes), and high users were less likely to achieve the Emergency Treatment Performance target versus moderate users (odds ratio 0.66; 95% confidence interval 0.50 to 0.86). There were no significant differences between the users in hospital admission and ED revisit rates.

CONCLUSION

Our findings suggest that reducing test use may reduce ED length of stay and improve the chance of achieving the Emergency Treatment Performance target.

The evolving role of coronary CT angiography in Acute Coronary Syndromes

In the United States, non-obstructive coronary disease has been on the rise, and each year, nearly one million adults suffer myocardial infarction, 70% of which are non-ST-segment elevation myocardial infarction (NSTEMI). In addition, approximately 15% of patients suffering NSTEMI will have subsequent readmission for a recurrent acute coronary syndrome (ACS). While invasive angiography remains the standard of care in the diagnostic and therapeutic approach to these patients, these methods have limitations that include procedural complications, uncertain specificity in diagnosis of the culprit lesion in patients with multi-vessel coronary artery disease (CAD), and challenges in following coronary disease over time. The role of coronary computed tomography angiography (CCTA) for evaluating patients with both stable and acute chest pain has seen a paramount upshift in the last decade. This paper reviews the established role of CCTA for the rapid exclusion of obstructive plaque in troponin negative acute chest pain, while exploring opportunities to address challenges in the current approach to evaluating NSTEMI.

Using Cardiac Magnetic Resonance Imaging to Evaluate Patients with Chest Pain in the Emergency Department

Chest pain is one of the most common presenting symptoms in the emergency department (ED). Among patients with abnormal troponins, it is imperative to quickly and accurately distinguish type 1 acute myocardial infarction (AMI) from other etiologies of myocardial injury. Although high-sensitivity troponin assays introduced a high negative predictive value for AMI, they have exposed the need for diagnostic modalities that can determine the etiology of acute myocardial injury. Cardiac magnetic resonance imaging (CMR) is an effective tool to risk stratifying chest pain among patients in the ED. CMR is non-invasive and has a lower cost of care and shorter length of stay compared to those of invasive coronary angiography. It also provides detailed information on cardiac morphology, function, tissue edema, and location and pattern of tissue damage that can help to differentiate many etiologies of cardiac injury. CMR is particularly useful to distinguish chest pain due to type 1 AMI versus supply-demand mismatch due to acute cardiac noncoronary artery disease. A detailed review of the literature has shown that CMR with stress testing is safe to use in patients presenting to the ED with chest pain, with or without abnormal troponins. CMR is a useful, safe, economical, and effective alternative to the traditional diagnostic tools that are typically used in this patient population. It is a practical tool to risk-stratify patients with possible cardiac pathology and to clarify diagnosis without invasive testing.

Coronary artery calcium testing in low-intermediate risk symptomatic patients with suspected coronary artery disease: An effective gatekeeper to further testing?

Computed tomography for quantification of coronary artery calcium (CAC) is a simple non-invasive tool to assess atherosclerotic plaque burden. CAC is highly correlated with coronary atherosclerosis and is a robust predictor of cardiovascular outcomes. Recently, the 2018 ACC/AHA Cholesterol Guidelines endorsed the use of CAC scores in asymptomatic, intermediate risk individuals where the decision to initiate stain therapy is uncertain. However, whether quantification of CAC may play a role in the assessment of symptomatic individuals remains a matter of debate. In this review, we examine the evidence for the use of CAC in low-intermediate risk patients with chest pain. This appraisal places a particular focus on the growing body of literature supporting the negative predictive value of a CAC score of zero to rule out significant coronary artery disease in those without high-risk features. We also evaluate current guidelines, limitations, and future research directions for CAC scoring in this important subgroup of patients.

CCTA in the diagnosis of coronary artery disease

The world of cardiac imaging is proposing to physicians an ever-increasing spectrum of options and tools with the disadvantages of patients presently submitted to multiple, sequential, time-consuming, and costly diagnostic procedures and tests, sometimes with contradicting results. In the last two decades, the CCTA has evolved into a valuable diagnostic test in today's patient care, changing the official existing guidelines and clinical practice with a pivotal role to exclude significant CAD, in the referral of patients to the Cath-Lab, in the follow-up after coronary revascularization, and finally in the cardiovascular risk stratification.

ST Elevations in the Era of COVID-19

Myocardial injury, represented by elevated cardiac enzymes, has been associated with increased morbidity and mortality in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections. Coronavirus disease 2019 (COVID-19) has created unique challenges in approaching patients with acute ST-segment changes. We describe two distinct cases of ST elevation on electrocardiogram occurring in patients with COVID-19 and review important diagnostic and management considerations for the front-line clinician.

Appropriate Use Criteria for Echocardiography in the Era of Value-Based Care: Mission Accomplished or Future Mandates?

Purpose of Review

The purpose of this review is to highlight the past impact and current role of the Appropriate Use Criteria (AUC) for echocardiography in value-based healthcare, and to address future implications in light of the recent mandate from the Centers for Medicare and Medicaid Services to incorporate AUC for other imaging modalities.

Recent Findings

Several studies have proven that the AUC effectively stratify the clinical practice of echocardiography as they predict important echo abnormalities and impact optimal patient care. Recent investigations have tested new technologies and demonstrated the feasibility and scalability of the application of the AUC for echocardiography at the point of care.

Summary

The AUC for echocardiography has accomplished their core mission, as utilization has moderated over the last decade and mandatory implementation at the point of care for echocardiography remains rare. While a new mandate signals another wave of focus on appropriate utilization, echocardiography stands ready.

Automated coronary artery atherosclerosis detection and weakly supervised localization on coronary CT angiography with a deep 3-dimensional convolutional neural network

We propose a fully automated algorithm based on a deep learning framework enabling screening of a coronary computed tomography angiography (CCTA) examination for confident detection of the presence or absence of coronary artery atherosclerosis. The system starts with extracting the coronary arteries and their branches from CCTA datasets and representing them with multi-planar reformatted volumes; pre-processing and augmentation techniques are then applied to increase the robustness and generalization ability of the system. A 3-dimensional convolutional neural network (3D-CNN) is utilized to model pathological changes (e.g., atherosclerotic plaques) in coronary vessels. The system learns the discriminatory features between vessels with and without atherosclerosis. The discriminative features at the final convolutional layer are visualized with a saliency map approach to provide visual clues related to atherosclerosis likelihood and location. We have evaluated the system on a reference dataset representing 247 patients with atherosclerosis and 246 patients free of atherosclerosis. With five fold cross-validation, an Accuracy = 90.9%, Positive Predictive Value = 58.8%, Sensitivity = 68.9%, Specificity of 93.6%, and Negative Predictive Value (NPV) = 96.1% are achieved at the artery/branch level with threshold 0.5. The average area under the receiver operating characteristic curve is 0.91. The system indicates a high NPV, which may be potentially useful for assisting interpreting physicians in excluding coronary atherosclerosis in patients with acute chest pain.

In-Hospital Cost Comparison of Triple-Rule-Out Computed Tomography Angiography Versus Standard of Care in Patients With Acute Chest Pain

PURPOSE

The purpose of this study was to evaluate the utilization of invasive and noninvasive tests and compare cost in patients presenting with chest pain to the emergency department (ED) who underwent either triple-rule-out computed tomography angiography (TRO-CTA) or standard of care.

MATERIALS AND METHODS

We performed a retrospective single-center analysis of 2156 ED patients who presented with acute chest pain with a negative initial troponin and electrocardiogram for myocardial injury. Patient cohorts matched by patient characteristics who had undergone TRO-CTA as a primary imaging test (n=1139) or standard of care without initial CTA imaging (n=1017) were included in the study. ED visits, utilization of tests, and costs during the initial episode of hospital care were compared.

RESULTS

No significant differences in the diagnosis of coronary artery disease, pulmonary embolism, or aortic dissection were observed. Median ED waiting time (4.5 vs. 7.0 h, P<0.001), median total length of hospital stay (5.0 vs. 32.0 h, P<0.001), hospital admission rate (12.6% vs. 54.2%, P<0.001), and ED return rate to our hospital within 30 days (3.5% vs. 14.6%, P<0.001) were significantly lower in the TRO-CTA group. Moreover, reduced rates of additional testing and invasive coronary angiography (4.9% vs. 22.7%, P<0.001), and ultimately lower total cost per patient (11,783$ vs. 19,073$, P<0.001) were observed in the TRO-CTA group.

CONCLUSIONS

TRO-CTA as an initial imaging test in ED patients presenting with acute chest pain was associated with shorter ED and hospital length of stay, fewer return visits within 30 days, and ultimately lower ED and hospitalization costs.

ASNC/AHA/ASE/EANM/HFSA/ISA/SCMR/SNMMI expert consensus recommendations for multimodality imaging in cardiac amyloidosis: Part 2 of 2-Diagnostic criteria and appropriate utilization

Cardiac amyloidosis is emerging as an underdiagnosed cause of heart failure and mortality. Growing literature suggests that a noninvasive diagnosis of cardiac amyloidosis is now feasible. However, the diagnostic criteria and utilization of imaging in cardiac amyloidosis are not standardized. In this paper, Part 2 of a series, a panel of international experts from multiple societies define the diagnostic criteria for cardiac amyloidosis and appropriate utilization of echocardiography, cardiovascular magnetic resonance imaging, and radionuclide imaging in the evaluation of patients with known or suspected cardiac amyloidosis.

Use of Initial Noninvasive Cardiac Testing and Association with Downstream Healthcare Resource: A Retrospective Review of Resources Used Across a 12-Month Window for Probable Type I Myocardial Infarction Patients

BACKGROUND

Clinical guidelines provide clinicians with substantial discretion in the use of noninvasive cardiac testing for patients with suspected coronary artery disease. Repeat testing, frequent emergency department (ED) visits, and increases in other cardiac-related procedures can be a burden on patients and payers and can complicate treatment planning. We assessed downstream healthcare resource utilization (HCRU) for patients undergoing initial single-photon emission computed tomography (SPECT), myocardial perfusion imaging (MPI), stress echocardiography (ECHO), or exercise treadmill testing (ETT) with probable type I myocardial infarction (MI).

METHODS

Electronic medical records data from 12,130 patients with probable type I MI presenting to EDs within a large healthcare system comprised of 11 adult hospitals were retrospectively analyzed. Logistic and linear regression determined the individual contribution of SPECT-MPI, ETT, and ECHO on repeat cardiovascular (CV) testing, inpatient visits, outpatient visits, and cardiac-related costs within 12 months of the index visit.

RESULTS

The majority of patients received SPECT-MPI for the index-testing event (56.5%), followed by ETT (29.2%) and ECHO (14.3%). Patients who had SPECT-MPI at the index visit were less likely to have a repeat CV testing visit (odds ratio [OR] 0.77, 95% confidence interval [CI] 0.62‒0.96; p = 0.020) or an inpatient visit (OR 0.70, 95% CI 0.49‒0.98; p = 0.039) than those who underwent ETT or ECHO. ETT and ECHO were not predictive of any outcome.

CONCLUSIONS

SPECT-MPI does not result in more downstream HCRU than ETT or ECHO and is associated with a lower likelihood of repeat non-invasive CV testing and inpatient visits.

The Association Between Marital Status, Coronary Computed Tomography Imaging Biomarkers, and Mortality in a Lung Cancer Screening Population

PURPOSE

The purpose of this study was to elucidate the impact of being unmarried on coronary computed tomography (CT) imaging biomarkers and mortality in a lung cancer screening population.

MATERIALS AND METHODS

In this retrospective case-control study, 5707 subjects (3777 married; mean age: 61.9±5.1 y and 1930 unmarried; mean age: 61.9±5.3 y) underwent low-dose CT as part of the National Lung Screening Trial (NLST). The median follow-up time was 6.5 (Q1-Q3: 5.6 to 6.9) years. Being unmarried was defined as never married, widowed, separated, or divorced. Being married was defined as married or living as married. Our primary endpoint was cardiovascular disease (CVD)-related death; our secondary endpoint was all-cause mortality. Coronary CT imaging biomarkers (calcium score, density, and volume) on low-dose chest CT scan were calculated using dedicated automatic software. Weighted Cox proportional-hazards regression was performed to examine the association between marital status and death. Kaplan-Meier curves were generated to visualize subject survival.

RESULTS

Being unmarried was significantly associated with an increased risk for CVD-related death (hazard ratio [HR]: 1.58; 95% confidence interval [CI]: 1.31-1.91) and all-cause mortality (HR: 1.39; 95% CI: 1.26-1.53), which remained significant even after adjusting for traditional cardiovascular risk factors (HR CVD death: 1.75; 1.44-2.12 and HR all-cause mortality: 1.58; 95% CI: 1.43-1.74) and coronary calcium score (HR CVD death: 1.58; 95% CI: 1.31-1.91 and HR all-cause mortality: 1.40; 95% CI: 1.27-1.54).

CONCLUSIONS

Being unmarried is associated with an increased CVD-related death and all-cause mortality mainly due to cardiovascular etiology. On the basis of this, marital status might be taken into consideration when assessing individuals' health status.

Timely identification of atypical acute aortic dissection in the emergency department:a study from a tertiary hospital

Background/aim

Acute aortic dissection (AAD) is a rare but fatal disease if left untreated. Symptoms are often similar to common conditions; therefore, the diagnostic strategy is important. We aimed to identify the atypical symptoms in a timely manner without putting patients at greater risk for undetected AAD.

Materials and methods

We conducted a retrospective observational study of 59 AAD patients with both atypical and typical symptoms from January 2012 to December 2016. Patients with atypical symptoms continuing more than 30 min underwent a D-dimer test and computed tomography (CT) or computed tomographic angiography (CTA).

Results

Of the 59 AAD patients, 22 were atypical. In the atypical group, the median delay time in our hospital was 3.1 h; average delay time after July 2015 was shorter than average delay time before June 2015 (16.59 ± 24.70 vs. 1.90 ± 0.57 h, P = 0.076).

Conclusions

For patients in the emergency department who are suspected of having AAD, incorporating atypical symptoms with high levels of D-dimer into a triage strategy could improve the efficiency of clinical decision making. Furthermore, essential education directed towards the recognition of the atypical symptoms of AAD for front-line physicians may aid in a timely diagnosis, as compared with the usual assessments in the emergency department.

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.

Spontaneous coronary artery dissection: etiology and recurrence

Introduction: Spontaneous coronary artery dissection (SCAD) is an increasingly appreciated cause of acute myocardial infarction (AMI) and sudden cardiac death most often affecting young to middle-aged women with few conventional cardiovascular risk factors. Areas covered: A literature search was performed using MedLine, PubMed, and Google Scholar (dating to 04/30/2019). Authors review the key clinical features of SCAD and highlight what is known regarding its pathophysiology and associated factors. The relationship between SCAD and other systemic vasculopathies, notably fibromuscular dysplasia (FMD) is also discussed. Authors also mention the management of acute SCAD along with considerations for long term follow-up such as chest pain syndrome, extracoronary vasculopathy screening, and recurrent SCAD. Expert opinion: Our understanding regarding the association of SCAD and other arteriopathies such as FMD is anticipated to grow. In addition, progress is likely to be made in our efforts to predict recurrent SCAD risk and define potential preventative strategies, possibly through the incorporation of adjunctive imaging.

Takotsubo cardiomyopathy in a man with no trigger and multiple cardioembolic complications-A rare constellation

Takotsubo Cardiomyopathy (TC) is an uncommon, transient, reversible cardiomyopathy, with a classic pattern of wall-motion abnormalities, usually seen in women after an emotional stressor. Despite its increased recognition, there remain gaps in the exact mechanisms, predisposing factors, and predictors of recovery; this is particularly true for males where the condition occurs far less frequently than in females. TC typically resolves within weeks, and the prognosis is favorable compared to acute coronary syndromes. Nonetheless, about 1% of cases may be complicated by left ventricular (LV) thrombus and embolism. Herein we describe an atypical case of a man with no obvious trigger, who developed TC with left ventricular thrombus and multiple embolic complications, but subsequently showed complete and full resolution. Multimodality imaging including echocardiography, cardiac CT and cardiac MRI was instrumental in this diagnostic dilemma, as well as useful in guiding treatment options and informing prognosis.

Initial evaluation of three-dimensionally printed patient-specific coronary phantoms for CT-FFR software validation

We developed three-dimensionally (3D) printed patient-specific coronary phantoms that are capable of sustaining physiological flow and pressure conditions. We assessed the accuracy of these phantoms from coronary CT acquisition, benchtop experimentation, and CT-FFR software. Five patients with coronary artery disease underwent 320-detector row coronary CT angiography (CCTA) (Aquilion ONE, Canon Medical Systems) and a catheter lab procedure to measure fractional flow reserve (FFR). The aortic root and three main coronary arteries were segmented (Vitrea, Vital Images) and 3D printed (Eden 260V, Stratasys). Phantoms were connected into a pulsatile flow loop, which replicated physiological flow and pressure gradients. Contrast was introduced and the phantoms were scanned using the same CT scanner model and CCTA protocol as used for the patients. Image data from the phantoms were input to a CT-FFR research software (Canon Medical Systems) and compared to those derived from the clinical data, along with comparisons between image measurements and benchtop FFR results. Phantom diameter measurements were within 1 mm on average compared to patient measurements. Patient and phantom CT-FFR results had an absolute mean difference of 4.34% and Pearson correlation of 0.95. We have demonstrated the capabilities of 3D printed patient-specific phantoms in a diagnostic software.

Diagnostic and Prognostic Role of the Modified Diamond-Forrester Model in Combination With Coronary Calcium Score in Acute Chest Pain Patients

BACKGROUND

The aim of this study was to evaluate whether pretest probability (PTP) assessment using the Diamond-Forrester Model (DFM) combined with coronary calcium scoring (CCS) can safely rule out obstructive coronary artery disease (CAD) and 30-day major adverse cardiovascular events (MACE) in acute chest pain patients.

METHODS

We retrospectively evaluated consecutive patients, age ≥18 years, with no known CAD, negative initial electrocardiogram, and troponin level. All patients had coronary computed tomographic angiography (CCTA) with CCS, and our final cohort consisted of 1988 patients. Obstructive CAD was defined as luminal narrowing of ≥50% in 1 or more vessels by CCTA. Patients were classified according to PTP as low (<10%), intermediate (10%-90%), or high (>90%).

RESULTS

The DFM classified 293 (14.7%), 1445 (72.7%), and 250 (12.6%) of patients as low, intermediate, and high risk, respectively, with corresponding 30-day MACE rates of 0.0%, 2.35%, and 14.8%. For patients with intermediate PTP and CCS ≤10, the negative predictive value was 99.2% (95% confidence interval: 98.7-99.8) for 30-day MACE while it was 92.62% (95% confidence interval: 87.9-97.3) for patients with high PTP. Among patients with a high PTP and CCS of zero, the prevalence of 30-day MACE and obstructive CAD remained high (7.07% and 10.1%, respectively).

CONCLUSIONS

In acute chest pain patients without evidence of ischemia on initial electrocardiogram and cardiac troponin, low PTP by DFM or the combination of intermediate PTP and CCS ≤10 had excellent negative predictive values to rule out 30-day MACE. CCS is not sufficient to exclude obstructive CAD and 30-day MACE in patients with high PTP.

Yield of CT pulmonary angiography in the diagnosis of acute pulmonary embolism: short report

OBJECTIVE

To assess computed tomography pulmonary angiography (CTPA) positive yield rate for pulmonary embolism (PE) in a Canadian academic tertiary center.

RESULTS

This one-center retrospective cross-sectional study includes from 5565 (model 1) to 5296 (model 2) patients that were evaluated for suspected PE in 2015, among which 1331 (23.9% (model 1) to 25.1% (model 2)) underwent CTPA. Mean age of CTPA patients was 60.2 ± 16.6 years, of which 575 were males (43.2%). Two hundred eleven CTPA examinations were positive for PE, giving a CTPA positive yield rate of 15.9% (95% CI (13.93-17.87)). One hundred and thirteen (8.1%) CTPA were considered indeterminate, and eleven were considered nondiagnostic (0.8%). Among the 211 CTPA positive for PE, 67 (32%) were proximal emboli, 98 (47%) were segmental emboli and 44 (21%%) were subsegmental emboli. In conclusion, in this retrospective study done in a Canadian academic tertiary center, we report a positive rate of 15.9% for PE detection with CTPA, which is above the generally accepted lower threshold of 10% for the yield of CTPA.

Acute Coronary and Acute Aortic Syndromes

Multidetector-row computed tomography (MDCT) can provide crucial information and rapid triage of emergency department patients with suspected acute coronary syndrome (ACS) or acute aortic syndrome (AAS). Coronary computed tomography angiography has high negative predictive value to rule out ACS, and MDCT is diagnostic for AAS and its variants. Optimization of acquisition technique and up-to-date knowledge of the pathophysiology of these conditions can improve study and interpretation quality for diagnosis of ACS or AAS.

State-of-the-art approach towards magnetic resonance imaging of the nervous system structures in patients with cardiac implantable electronic devices

INTRODUCTION

MRI generated forces are the source of potential complications in patients with cardiac implantable electronic devices (CIED). The technological progress, and growing clinical evidence concerning the operation of the contemporary MR non-conditional CIEDs during MRI, have started to significantly change our every-day clinical practice. Nevertheless, a lot of patients who could have an MRI performed safely, still have been refused the examination.

STATE-OF-THE-ART

In many clinical situations, an MRI examination in a patient with a CIED is reasonable, and is linked to a negligible risk of complications if performed under strict precautions. The MagnaSave Registry that evaluated the influence of nonthoracic MRI on the function of MR non-conditional CIEDs, and numerous studies involving thoracic and non-thoracic MRIs in patients with legacy CIEDs, have confirmed the feasibility and safety of such examinations. In this article, practical tips aimed towards improving the safety of MRI in MR conditional and non-conditional CIED patients are largely based on the very recently released (2017) HRS expert consensus statement.

CLINICAL IMPLICATIONS

Clinical data emphasize the necessity of making the MRI more accessible to CIED patients, also in the case of MR non-conditional systems or when the thorax MR imaging is clinically reasonable. This goal should be achieved by increasing the number of centers complying with respective recommendations and applying protocols that would guarantee the highest safety level.

FUTURE DIRECTIONS

Further studies are warranted to assess safety issues related to the main current contraindication to MRI, i.e., the presence of abandoned leads.

Diagnostic chest ultrasound for acute respiratory failure

Acute respiratory failure (ARF) is a common life-threatening medical condition, with multiple underlying aetiologies. Diagnostic chest ultrasound provides accurate diagnosis of conditions that commonly cause ARF, and may improve overall diagnostic accuracy in critical care settings as compared to standard diagnostic approaches. Respiratory physicians are becoming increasingly familiar with ultrasound as a part of routine clinical practice, although the majority of data to date has focused on the emergency and intensive care settings. This review will examine the evidence for the use of diagnostic chest ultrasound, focusing on different levels of imaging efficacy; specifically ultrasound test attributes, impacts on clinician behaviour and impact on health outcomes. The evidence behind use of multi-modality ultrasound examinations in ARF will be reviewed. It is hoped that readers will become familiar with the advantages and potential issues with chest ultrasound, as well as evidence gaps in the field.