Cardiac Computed Tomography Imaging Research Articles

Left atrium and pulmonary vein imaging using sub-millisiviert cardiac computed tomography: Impact on radiofrequency catheter ablation cumulative radiation exposure and outcome in atrial fibrillation patients

BackgroundThe outcome of radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) has improved thanks to left atrium (LA) anatomy reconstruction by cardiac computed tomography (CCT). A new model-based iterative reconstruction algorithm (MBIR) provides image noise reduction achieving effective radiation dose (ED) close to chest X-ray exposure. Aim of this study was comparing RFCA procedural characteristics, AF recurrence and radiation exposure between patients in whom RFCA was guided by CCT image integration with MBIR versus a CCT standard protocol. MethodsThree-hundred consecutive patients with drug-refractory AF were studied with CCT using MBIR (Group 1; N:150) or CCT with standard protocol (Group 2; N:150) for LA evaluation and treated by image integration-supported RFCA. Image noise, signal to noise ratio (SNR), contrast to noise ratio (CNR), RFCA procedural characteristics, rate of AF recurrence and radiation exposure were compared. ResultsGroup 1 showed higher SNR (25.9±7.1 vs. 16.2±4.8, p<0.001) and CNR (23.3±7.1 vs. 12.2±4.2, p<0.001) and lower image noise (22.3±5.2 vs. 32.6±8.1 HU, p<0.001), fluoroscopy time (21±12 vs. 29±15min, p<0.01) and procedural duration (135±89 vs. 172±55, p<0.001). Group 1 showed a 94% reduction of ED as compared to Group 2 (CCT-ED related: 0.41±0.04 vs. 6.17±4.11mSv, p<0.001; cumulative CCT+RFCA-ED related: 21.9±17.9 vs. 36.0±24.1mSv, p<0.001) with similar rate of AF recurrence (25% vs. 29%, p=0.437). ConclusionsCCT with MBIR allows accurate reconstruction of LA anatomy in AF patients undergoing RFCA with a sub-millisievert ED and comparable success rate of RFCA as compared to a standard CCT scan protocol.

Insights from Novel Noninvasive CT and ECG Imaging Modalities on Electromechanical Myocardial Activation in a Canine Model of Ischemic Dyssynchronous Heart Failure.

The interplay between electrical activation and mechanical contraction patterns is hypothesized to be central to reduced effectiveness of cardiac resynchronization therapy (CRT). Furthermore, complex scar substrates render CRT less effective. We used novel cardiac computed tomography (CT) and noninvasive electrocardiographic imaging (ECGI) techniques in an ischemic dyssynchronous heart failure (DHF) animal model to evaluate electrical and mechanical coupling of cardiac function, tissue viability, and venous accessibility of target pacing regions. Ischemic DHF was induced in 6 dogs using coronary occlusion, left bundle ablation and tachy RV pacing. Full body ECG was recorded during native rhythm followed by volumetric first-pass and delayed enhancement CT. Regional electrical activation were computed and overlaid with segmented venous anatomy and scar regions. Reconstructed electrical activation maps show consistency with LBBB starting on the RV and spreading in a "U-shaped" pattern to the LV. Previously reported lines of slow conduction are seen parallel to anterior or inferior interventricular grooves. Mechanical contraction showed large septal to lateral wall delay (80 ± 38 milliseconds vs. 123 ± 31 milliseconds, P = 0.0001). All animals showed electromechanical correlation except dog 5 with largest scar burden. Electromechanical decoupling was largest in basal lateral LV segments. We demonstrated a promising application of CT in combination with ECGI to gain insight into electromechanical function in ischemic dyssynchronous heart failure that can provide useful information to study regional substrate of CRT candidates.

Submillisievert Radiation Dose Coronary CT Angiography: Clinical Impact of the Knowledge-Based Iterative Model Reconstruction

The purpose of this study was to evaluate the noise and image quality of images reconstructed with a knowledge-based iterative model reconstruction (knowledge-based IMR) in ultra-low dose cardiac computed tomography (CT). We performed submillisievert radiation dose coronary CT angiography on 43 patients. We also performed a phantom study to evaluate the influence of object size with the automatic exposure control phantom. We reconstructed clinical and phantom studies with filtered back projection (FBP), hybrid iterative reconstruction (hybrid IR), and knowledge-based IMR. We measured effective dose of patients and compared CT number, image noise, and contrast noise ratio in ascending aorta of each reconstruction technique. We compared the relationship between image noise and body mass index for the clinical study, and object size for phantom study. The mean effective dose was 0.98 ± 0.25 mSv. The image noise of knowledge-based IMR images was significantly lower than those of FBP and hybrid IR images (knowledge-based IMR: 19.4 ± 2.8; FBP: 126.7 ± 35.0; hybrid IR: 48.8 ± 12.8, respectively) (P < .01). The contrast noise ratio of knowledge-based IMR images was significantly higher than those of FBP and hybrid IR images (knowledge-based IMR: 29.1 ± 5.4; FBP: 4.6 ± 1.3; hybrid IR: 13.1 ± 3.5, respectively) (P < .01). There were moderate correlations between image noise and body mass index in FBP (r = 0.57, P < .01) and hybrid IR techniques (r = 0.42, P < .01); however, these correlations were weak in knowledge-based IMR (r = 0.27, P < .01). Compared to FBP and hybrid IR, the knowledge-based IMR offers significant noise reduction and improvement in image quality in submillisievert radiation dose cardiac CT.

Incidence and appearances of coronary sinus anomalies in adults on cardiac CT.

The aim of this study was to analyze the frequency and appearances of coronary sinus (CS) anomalies on cardiac computed tomography (CT) of adult patients and to compare them with transthoracic echocardiography (TTE) findings. We retrospectively evaluated cardiac CT images for the presence of CS anomalies in 6936 adult patients who underwent imaging from April 1 2008 to March 31 2015 at our institution. We also reviewed and compared with TTE findings for the cases of CS anomalies. CS anomalies were diagnosed in 23 of the 6936 (0.33%) and included persistence of the left superior vena cava (PLSVC) in 19 cases, unroofed CS (UCS) in two, coronary artery-CS fistula in two, and CS atresia in one. TTE revealed CS dilatation in only five of the 16 cases of PLSVC and suggested CS anomaly in the two cases of coronary artery-CS fistula. The other cases of CS anomaly were detected incidentally on CT. The incidence of CS anomalies was 0.33%. Precise diagnosis of CS anomalies with TTE and the original transverse images on cardiac CT alone was difficult for some conditions. We should be alert for the presence of CS anomalies which can cause clinical or procedural complications.

Characterization of normal and scarred myocardium based on texture analysis of cardiac computed tomography images.

An accurate detection of myocardial scar using Cardiac CT may have a strong clinical impact; however, the main drawback is the insufficient contrast to noise ratio of delayed iodine enhanced (DIE) CT images, which makes its accurate segmentation (manual as well as automatic) difficult. In this work, we investigate texture parameters applied on the different scans in order to obtain the scans and features that best differentiates normal from scarred myocardium. The experiments on 7 cases of myocarditis show the accuracy of the parameter energy in all scans, as well as the good performance of the angiographic scan (having higher spatial resolution) with different parameters for the segmentation propose. Moreover, the best performance was obtained on the baseline scan for the energy feature, with an accuracy of 94%.

Computed tomography imaging to quantify the area of the endocardial subvalvular apparatus in hypertrophic cardiomyopathy – Relationship to outflow tract obstruction and symptoms

BackgroundAbnormalities of the endocardial subvalvular apparatus (SVA), which includes the papillary muscles directly attached to the mitral leaflet and left ventricular apical-basal muscle bundles, are occasionally identified in hypertrophic cardiomyopathy (HCM). Their associations with left ventricular outflow tract (LVOT) obstruction are unknown. MethodsWe retrospectively reviewed cardiac computed tomography image data sets of 107 consecutive patients with HCM [56 obstructive (HOCM) and 51 non-obstructive (HNOCM)] as well as 53 controls. We evaluated anomalies of the SVA, measured the cross-sectional area of the SVA at the level of the LVOT, and subsequently assessed its correlation with the LVOT pressure gradient with and without medication. ResultsThe area of the SVA was greater in HOCM than in HNOCM patients and in the control group (2.5 ± 1.3 cm2, 1.4 ± 0.8 cm2, and 0.9 ± 0.6 cm2, respectively; p < 0.0001). Anomalies in the SVA were more often observed in the HOCM group than in the HNOCM patients and controls (abnormal papillary muscles, 14%, 8%, and 0%, respectively; P = 0.010; LV apical–basal muscle bundles, 73%, 65%, and 45%, respectively; P = 0.0094). Among HOCM patients, logistic regression analysis demonstrated that an SVA area of 2.2 cm2 was an independent risk factor of residual severe LVOT obstruction (≥50 mmHg) after medication (odds ratio, 10.1; 95% confidence interval, 2.05–49.80). ConclusionAn increased area of the endocardial subvalvular apparatus could be an independent risk factor for clinically relevant LVOT obstruction refractory to medication.

State-of-the-Art CT Imaging of the Left Atrium

Cardiac computed tomography (CT) angiography with its high spatial and temporal resolution is a robust anatomical imaging tool. Beyond coronary artery examination in suspected coronary artery disease, cardiac CT is a helpful modality to depict cardiac morphology in surgical and percutaneous structural interventions planning. Conditions related to the left atrium are diverse; therefore, the importance of CT imaging is becoming more frequent. Latest technological advancements allow for low radiation dose image acquisition along with improved image quality detailed visualization of the left atrium during interventional procedure planning. In addition, left atrial imaging provides additional information regarding stroke risk, cardiovascular outcomes, congestive heart failure, and arrhythmia mechanisms. Therefore, the left atrium has been proposed as a barometer of cardiac function and cardiovascular risk. Cardiac CT has become an indispensable tool in the electrophysiology laboratory in the guidance of complex procedures, including trans-catheter pulmonary vein isolation in the treatment of drug-refractory atrial fibrillation. The detailed visualization of left atrial morphology and pulmonary vein anatomy is frequently helpful in achieving therapeutic success and avoiding complications.

Epicardial Adipose Tissue Volume and Left Ventricular Myocardial Function Using 3-Dimensional Speckle Tracking Echocardiography

BackgroundAlthough epicardial adipose tissue (EAT) volume is associated with increased incidence of coronary artery disease (CAD), its role in myocardial systolic dysfunction is unclear. The present study aimed to identify independent determinants of EAT volume in patients without obstructive CAD, and to evaluate the association between EAT volume (vs other measures of obesity) and myocardial systolic strain analysis. MethodsWe prospectively recruited 130 patients without obstructive CAD on contrast-enhanced cardiac computed tomography imaging and normal left ventricular ejection fraction on 3-dimensional (3D) echocardiography. EAT volume was quantified from cardiac computed tomography imaging, and 3D multidirectional (longitudinal, circumferential, radial, and area) strain were measured. ResultsThe mean EAT volume was 97.5 ± 43.7 cm3. In multivariable analysis, measures of obesity (body mass index [P = 0.007] and waist/hip ratio [P = 0.001]) were independently associated with larger EAT volume. EAT volume was correlated with 3D global longitudinal (r = 0.601; P < 0.001), circumferential (r = 0.375; P < 0.001), radial (r = −0.546; P < 0.001), and area (r = 0.558; P < 0.001) strain. In multivariable analyses, epicardial fat volume was the strongest predictor of 3D global longitudinal (standardized β = 0.512; P < 0.001), circumferential (standardized β = 0.242; P = 0.006), radial (standardized β = −0.422; P < 0.001), and area (standardized β = 0.428; P < 0.001) strain. In contrast, other measures of obesity including body mass index and waist/hip ratio were not independent determinants of 3D multidirectional global strain (all P > 0.05). ConclusionsEAT volume is independently associated with impaired myocardial systolic function despite preserved 3D left ventricular ejection fraction and absence of obstructive CAD, and might play a significant role in the pathophysiology of diabetic, obesity, and metabolic heart disease.

Training in Cardiac CT: a Continuously Evolving Modality

Over the past decade, the field of cardiac computed tomography (CCT) has experienced rapid evolution from an obscure curiosity to a powerful prognostic imaging modality for the evaluation of cardiovascular disease in a wide variety of clinical settings. Coronary CT angiography (CCTA) and coronary artery calcium (CAC) scoring for the diagnosis of coronary artery disease (CAD) in symptomatic and asymptomatic patients, respectively, remains the cornerstone of CCT imaging. In recent years, significant advances have been made in the evaluation of valvular heart disease, ischemic testing, and structural heart disease that require continual updating of any comprehensive CCT training curriculum. This rapid increase in data and potential applications of CCT provides a unique challenge in developing a training curriculum for CCT. Additionally, CCT imagers originate from a myriad of training backgrounds and, thus, may need very different didactic and hands-on training in order to build toward a common goal of CCT competence. In this review, current training statements and guidelines from a variety of sources are reviewed in the context of highlighting the keys to developing and maintaining a comprehensive CCT curriculum in the current era.

Cardiac MR and CT imaging in children with suspected or confirmed pulmonary hypertension/pulmonary hypertensive vascular disease. Expert consensus statement on the diagnosis and treatment of paediatric pulmonary hypertension. The European Paediatric Pulmonary Vascular Disease Network, endorsed by ISHLT and DGPK

Childhood pulmonary hypertension (PH) is a heterogenous disease associated with considerable morbidity and mortality. Invasive assessment of haemodynamics is crucial for accurate diagnosis and guidance of medical therapy. However, adequate...

Impact of Implementing Cardiac CT in Evaluating Patients Suspected of Cardioembolic Stroke

In practice, clinical and logistic hurdles may hamper performing transesophageal echocardiography in stroke patients. Cardiac computed tomography (CT) is a recently introduced noninvasive modality able to detect various embolic causes. Thus, we retrospectively assessed possible added values of applying cardiac CT in the real-world work-up of suspected cardioembolic stroke cases. Forty-seven patients were neurology service referrals for suspected cardioembolic stroke. The CT images and clinical reports of our cardiac CT radiologists were retrospectively evaluated. Cardiac CT was assessed in terms of detecting major embolic potential findings, potentially significant stroke-unrelated findings, and coronary arterial disease (CAD). Computed tomography results were correlated with echocardiographic reports. Cardiac CT showed findings of major embolic potential in 10 patients (21%, 5 thrombi cases, 2 vasculitis cases, 1 case of metastasis invading the left superior pulmonary artery, 1 myocardial infarction case, and 1 pulmonary arteriovenous malformations case), none of which were documented in echocardiography reports. Two cases (4%) with findings of major embolic potential where identified on echocardiography but not on CT (1 left atrial appendage thrombus and 1 mitral valve vegetation). Computed tomography of 13 patients (28%) showed 16 potentially significant stroke-unrelated findings. Twenty-one patients (47%) had unexpected CAD on CT, 11 (52%) of which were obstructive. Implementing cardiac CT in assessing patients suspected of cardioembolic stroke added value to echocardiographic evaluation, by detecting major embolic potential findings. In addition, cardiac CT revealed additional potentially significant stroke-unrelated findings and CAD.

Non-coronary abnormalities of the left heart: CT angiography findings.

Cardiac computed tomography (CT) is most commonly performed for the evaluation of the coronary arteries; however, non-coronary cardiac pathologies are frequently detected on these scans. In cases where magnetic resonance imaging cannot be used, cardiac CT can serve as the first-line imaging modality to evaluate many non-coronary cardiac pathologies. In this article, we discuss congenital non-coronary abnormalities of the left heart and their cardiac CT imaging features.

Renal sinus fat volume on computed tomography in middle-aged patients at risk for cardiovascular disease and its association with coronary artery calcification

ObjectiveRenal sinus fat (RSF) behaves as one of the perivascular fats, however RSF volume (RSFV) is considerably affected by visceral adipose tissue volume (VTAV). The ratio of RSFV to VATV (RSFV/VATV ratio) can be an index of regional perivascular fat accumulation corrected for the influence of VATV. The aim of this study was to investigate the relation between RSFV/VATV ratio and coronary artery calcium (CAC) in patients with suspected coronary artery disease. MethodsOne hundred and eighty-nine patients (mean age 66.7 ± 10.2; 72% men) underwent ECG-gated cardiac computed tomography (CT) and unenhanced abdominal CT. CAC score (CACS) was assessed using axial CT images. RSFV was measured by partially manipulated segmentation of the right kidney. VATV was automatically quantified in the upper abdomen. Logistic and correlation analyses were performed to examine the correlations between CAC, RSFV/VATV ratio, and risk factors of cardiovascular diseases in total and subgroups classified by the patients' age. ResultsLog-transformed RSFV/VATV ratio was associated with CAC presence in 112 middle-aged patients less than 69 years of age as well as total. This association remained significant after multivariate adjustment only in the middle-aged patients (OR 15.9, 95% CI 1.15–218.8). In total, RSFV/VATV ratio (r = 0.228, p = 0.002) and age (r = 0.316, p < 0.001) correlated with CACS on univariate analyses, but only age correlated on multivariate analyses. RSFV/VATV ratio correlated with CACS in the middle-aged patients (r = 0.418, p < 0.001), as well as on multivariate analyses. ConclusionsWe demonstrated that RSFV/VATV could be an independent risk indicator of CAC in the middle-aged patients.

CT imaging features of atrioventricular shunts: what the radiologist must know.

In the last decade, cardiac computed tomography (CT) has gained mainstream acceptance for the noninvasive exclusion of significant coronary disease in a selected population. Improvements in electrocardiogram (ECG)-triggered imaging techniques also allow, by extension, a proper evaluation of the complete heart anatomy. Given the increasing worldwide clinical implementation of cardiac CT for coronary artery evaluation, radiologists can, incidentally, be confronted with unfamiliar and previously unsuspected non-coronary cardiac pathologies, including congenital morphological defects. This presence of congenital heart disease (CHD) should not be overlooked, being the most common form of birth defect, with a total birth prevalence of 9.1 per 1000 live births worldwide [1]. The prevalence of adult patients with CHD is estimated to be 3000 per million adults [2]. Ventricular septal defects (VSDs) are the most frequent subtypes of CHD, accounting together with atrial septal defects (ASDs) for nearly half of all CHD cases [1]. While some small defects are rarely symptomatic and can go undetected for life, others are clinically significant and require adequate and timely medical intervention. In this article, we present the CT imaging features of atrioventricular (AV) shunts, highlighting both their embryological origins and associated relevant clinical features.Teaching points• Congenital heart disease (CHD) is the most common birth defect.• Ventricular and atrial septal defects account for nearly half of CHD cases.• Atrioventricular defects can frequently be detected on a cardiac CT.• Radiologists must be able to identify clinically significant atrioventricular defects.

Cardiac computed tomography imaging in familial hypercholesterolaemia

The purpose of the present review is to summarize the potential clinical applications of computed tomographic angiography (CTA) in familial hypercholesterolemia so far and recent advances of CTA research in other high-risk patients. Long-term, aggressively statin-treated, asymptomatic familial hypercholesterolemia patients may still have dramatic coronary artery disease (CAD). A clear association between the presence and the extent of nonobstructive CAD and all-cause mortality was found in the COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter registry. Notably, baseline statin therapy was associated with a significantly lower mortality for individuals with atherosclerotic plaque on CTA, but not for individuals with normal coronary arteries. CTA imaging has made clear that an increased plaque burden can be present even among asymptomatic, long-term aggressively statin-treated familial hypercholesterolemia patients. In the COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter registry, nonobstructive CAD predicted all-cause mortality and statin treatment improved the life span of persons with nonobstructive CAD. Clinical trials with CTA are required to develop and test identification of CAD and personalized treatment strategies for familial hypercholesterolemia.

Cardiac Physiology for Radiologists: Review of Relevant Physiology for Interpretation of Cardiac MR Imaging and CT.

Cardiac computed tomography (CT) and magnetic resonance (MR) imaging provide clinicians with important insights into cardiac physiology and pathology. However, not all radiologists understand the language and concepts of cardiac physiology that are used daily by cardiologists. This review article covers basic cardiac physiology as it relates to cardiac CT and MR imaging. Topics include a review of the cardiac cycle and left ventricular pressure-volume loops as they relate to different pathologic states, evaluation of cardiac function, and calculation of key parameters such as left ventricular volumes and the ejection fraction. The hemodynamics of cardiac shunts are covered, with an emphasis on factors important to cardiologists, including the ratio of pulmonary flow to systemic flow. Additionally, valvular physiologic function is reexamined, with a focus on understanding pressure gradients within the heart and also the changes associated with valvular pathologic conditions, including measurement of regurgitant fractions in patients with valvular insufficiency. Understanding these basic concepts will help radiologists tailor the reporting of cardiac studies to clinically relevant information.

Subprosthetic Pannus after Aortic Valve Replacement Surgery: Cardiac CT Findings and Clinical Features.

To investigate the cardiac computed tomographic (CT) findings and clinical implications of subprosthetic pannus in patients who have undergone aortic valve replacement. The institutional review board approved this retrospective study, and the need to obtain written informed consent was waived. From April 2011 to March 2012, 88 patients (mean age, 63 years; 45 men) with a prosthetic aortic valve who underwent cardiac CT were retrospectively selected. Dynamic cardiac CT images were analyzed by using a multiplanar reformatted technique. The presence or absence of subprosthetic pannus and its extent were evaluated at cardiac CT. The geometric orifice area and the effective orifice area of each prosthetic valve were measured to enable analysis of the pannus encroachment ratio in the systolic phase. Hemodynamic parameters at echocardiography, including mean transprosthetic pressure gradient (MTPG), were compared between patients with and those without pannus. The encroachment ratio and the MTPG were correlated by using the Spearman test to evaluate the relationship between the two variables. Seventeen patients (19%) had subprosthetic pannus at cardiac CT. In patients with subprosthetic pannus, MTPG, peak pressure gradient, transvalvular peak velocity, and left ventricular ejection fraction (LVEF) were significantly higher than in patients without pannus (MTPG: 28.1 mm Hg ± 19.8 [standard deviation] vs 14.0 mm Hg ± 6.5, P = .004; peak pressure gradient: 53.1 mm Hg ± 38.4 vs 26.1 mm Hg ± 11.4, P = .004; transvalvular peak velocity: 3.3 m/sec ± 1.3 vs 2.5 m/sec ± 0.5; and LVEF: 64.7% ± 7.4 vs 56.8% ± 10.5, P = .004). A high MTPG (≥40 mm Hg) was observed in four patients at echocardiography, and subprosthetic panni were identified at CT in all four patients. In patients with increased MTPGs, the encroachment ratio by subprosthetic pannus at CT was significantly higher than that in patients with MTPGs of less than 40 mm Hg (42.7 ± 13.3 vs 7.6 ± 3, P = .012). Cardiac CT revealed subprosthetic pannus to be a cause of the hemodynamic changes in patients who had undergone aortic valve replacement. By helping quantify the encroachment ratio by pannus, cardiac CT may help differentiate which subprosthetic panni might lead to substantial flow limitation over the prosthetic aortic valve.

Left ventricular apical diverticulum associated with double outlet right ventricle

Corresponding author: Muhammet Akyuz, M.D. Ege Universitesi Tip Fakultesi Kalp ve Damar Cerrahisi Anabilim Dali, 35100 Bornova, Izmir, Turkey. Tel: +90 232 388 11 15 e-mail: drmak100@gmail.com A six-year-old boy was admitted to our hospital for surgery for cardiac anomaly. The patient’s medical history included a right 5 mm sided modified Blalock-Taussig shunt through median sternotomy incision. Physical examination was normal, except a pulsatile mass localized in the epigastric area starting near inferior portion of the xiphoid process. Transthoracic echocardiography revealed double outlet right ventricle, subaortic ventricular septal defect, pulmonary stenosis, and patent right-sided shunt. An outpouching in the left ventricle apex which freely communicated with the left ventricle cavity through a narrow neck was observed. The diverticulum showed characteristics synchronous contractility with the left ventricle. The patient had normal left ventricular function without any evidence of thrombus in the left ventricular cavity or diverticulum. Cardiac computed tomography images revealed focal outpouching in the apical wall of the left ventricle, consistent with a congenital muscular diverticulum of the left ventricle apex (Figure 1). The patient was operated through re-median sternotomy incision and the apical diverticulum was visualized (Figure 2). After initiating cardiopulmonary bypass, Rastelli procedure was performed. At the end of the procedure, the left ventricular diverticulum was resected and primarily closed.

Identification of Coronary Artery Calcification and Diagnosis of Coronary Artery Disease by Abdominal CT: A Resident Education Continuous Quality Improvement Project

Coronary artery calcium (CAC) scoring is an excellent imaging tool for subclinical atherosclerosis detection and risk stratification. We hypothesize that although CAC has been underreported in the past on computed tomography (CT) scans of the abdomen, specialized resident educational intervention can improve on this underreporting. Beginning July 2009, a dedicated radiology resident cardiac imaging rotation and curriculum was initiated. A retrospective review of the first 500 abdominal CT reports from January 2009, 2011, and 2013 was performed including studies originally interpreted by a resident and primary attending physician interpretations. Each scan was reevaluated for presence or absence of CAC and coronary artery disease (CAD) by a cardiovascular CT expert reader. These data were then correlated to determine if the presence of CAC had been properly reported initially. The results of the three time periods were compared to assess for improved rates of CAC and CAD reporting after initiation of a resident cardiac imaging curriculum. Statistically significant improvements in the reporting of CAC and CAD on CT scans of the abdomen occurred after the initiation of formal resident cardiac imaging training which included two rotations (4 weeks each) of dedicated cardiac CT and cardiac magnetic resonance imaging interpretation during the resident's second, third, or fourth radiology training years. The improvement was persistent and increased over time, improving from 1% to 72% after 2 years and to 90% after 4 years. This single-center retrospective analysis shows association between implementation of formal cardiac imaging training into radiology resident education and improved CAC detection and CAD reporting on abdominal CT scans.

Noninvasive Tests for the Diagnostic Evaluation of Dyspnea Among Outpatients: The Multi-Ethnic Study of Atherosclerosis Lung Study

BackgroundDyspnea on exertion is a common and debilitating symptom, yet evidence for the relative value of cardiac and pulmonary tests for the evaluation of chronic dyspnea among adults without known cardiac or pulmonary disease is limited. MethodsThe Multi-Ethnic Study of Atherosclerosis (MESA) enrolled participants aged 45 to 84 years who were free of clinical cardiovascular disease from 6 communities; participants with clinical pulmonary disease were excluded from this report. Dyspnea on exertion was assessed via structured interview. Tests included electrocardiograms, cardiac computed tomography (CT) for coronary artery calcium, cardiac magnetic resonance imaging, spirometry, percent emphysema (percent of lung regions <−950 HU) on CT, inflammatory biomarkers, and N-terminal pro-brain natriuretic peptide (NT-proBNP). Logistic regression was used to identify independent correlates of dyspnea after adjustment for age, sex, body mass index, physical activity, anxiety, and leg pain. ResultsAmong 1969 participants without known cardiopulmonary disease, 9% had dyspnea. The forced expiratory volume in 1 second (FEV1) (P < .001), NT-proBNP (P = .004), and percent emphysema on CT (P = .004) provided independent information on the probability of self-reported dyspnea. Associations with the FEV1 were stronger among smokers and participants with other recent respiratory symptoms or seasonal allergies; associations with NT-proBNP were present only among participants with coexisting symptoms of lower-extremity edema. Only the FEV1 provided a significant improvement in the receiver operating curve. ConclusionsAmong adults without known cardiac or pulmonary disease reporting dyspnea on exertion, spirometry, NT-proBNP, and CT imaging for pulmonary parenchymal disease were the most informative tests.