Cardiac magnetic resonance assessment of cardiac involvement in autoimmune diseases.

Cardiac magnetic resonance (CMR) is emerging as the modality of choice to assess early cardiovascular involvement in patients with autoimmune rheumatic diseases (ARDs) that often has a silent presentation and may lead to changes in management. Besides being reproducible and accurate for functional and volumetric assessment, the strength of CMR is its unique ability to perform myocardial tissue characterization that allows the identification of inflammation, edema, and fibrosis. Several CMR biomarkers may provide prognostic information on the severity and progression of cardiovascular involvement in patients with ARDs. In addition, CMR may add value in assessing treatment response and identification of cardiotoxicity related to therapy with immunomodulators that are commonly used to treat these conditions. In this review, we aim to discuss the following objectives: •Illustrate imaging findings of multi-parametric CMR approach in the diagnosis of cardiovascular involvement in various ARDs;•Review the CMR signatures for risk stratification, prognostication, and guiding treatment strategies in ARDs;•Describe the utility of routine and advanced CMR sequences in identifying cardiotoxicity related to immunomodulators and disease-modifying agents in ARDs;•Discuss the limitations of CMR, recent advances, current research gaps, and potential future developments in the field.

Prediction of future healthcare expenses of patients from chest radiographs using deep learning: a pilot study.

Our objective was to develop deep learning models with chest radiograph data to predict healthcare costs and classify top-50% spenders. 21,872 frontal chest radiographs were retrospectively collected from 19,524 patients with at least 1-year spending data. Among the patients, 11,003 patients had 3 years of cost data, and 1678 patients had 5 years of cost data. Model performances were measured with area under the receiver operating characteristic curve (ROC-AUC) for classification of top-50% spenders and Spearman ρ for prediction of healthcare cost. The best model predicting 1-year (N = 21,872) expenditure achieved ROC-AUC of 0.806 [95% CI 0.793-0.819] for top-50% spender classification and ρ of 0.561 [0.536-0.586] for regression. Similarly, for predicting 3-year (N = 12,395) expenditure, ROC-AUC of 0.771 [0.750-0.794] and ρ of 0.524 [0.489-0.559]; for predicting 5-year (N = 1779) expenditure ROC-AUC of 0.729 [0.667-0.729] and ρ of 0.424 [0.324-0.529]. Our deep learning model demonstrated the feasibility of predicting health care expenditure as well as classifying top 50% healthcare spenders at 1, 3, and 5 year(s), implying the feasibility of combining deep learning with information-rich imaging data to uncover hidden associations that may allude to physicians. Such a model can be a starting point of making an accurate budget in reimbursement models in healthcare industries.

Machine learning in cardiovascular radiology: ESCR position statement on design requirements, quality assessment, current applications, opportunities, and challenges.

Machine learning offers great opportunities to streamline and improve clinical care from the perspective of cardiac imagers, patients, and the industry and is a very active scientific research field. In light of these advances, the European Society of Cardiovascular Radiology (ESCR), a non-profit medical society dedicated to advancing cardiovascular radiology, has assembled a position statement regarding the use of machine learning (ML) in cardiovascular imaging. The purpose of this statement is to provide guidance on requirements for successful development and implementation of ML applications in cardiovascular imaging. In particular, recommendations on how to adequately design ML studies and how to report and interpret their results are provided. Finally, we identify opportunities and challenges ahead. While the focus of this position statement is ML development in cardiovascular imaging, most considerations are relevant to ML in radiology in general. KEY POINTS: • Development and clinical implementation of machine learning in cardiovascular imaging is a multidisciplinary pursuit. • Based on existing study quality standard frameworks such as SPIRIT and STARD, we propose a list of quality criteria for ML studies in radiology. • The cardiovascular imaging research community should strive for the compilation of multicenter datasets for the development, evaluation, and benchmarking of ML algorithms.

Cardiovascular disease in women: insights from magnetic resonance imaging.

The presentation and identification of cardiovascular disease in women pose unique diagnostic challenges compared to men, and underrecognized conditions in this patient population may lead to clinical mismanagement.This article reviews the sex differences in cardiovascular disease, explores the diagnostic and prognostic role of cardiovascular magnetic resonance (CMR) in the spectrum of cardiovascular disorders in women, and proposes the added value of CMR compared to other imaging modalities. In addition, this article specifically reviews the role of CMR in cardiovascular diseases occurring more frequently or exclusively in female patients, including Takotsubo cardiomyopathy, connective tissue disorders, primary pulmonary arterial hypertension and peripartum cardiomyopathy. Gaps in knowledge and opportunities for further investigation of sex-specific cardiovascular differences by CMR are also highlighted.

Extending Cardiac Functional Assessment with Respiratory-Resolved 3D Cine MRI.

This study aimed to develop a cardiorespiratory-resolved 3D magnetic resonance imaging (5D MRI: x-y-z-cardiac-respiratory) approach based on 3D motion tracking for investigating the influence of respiration on cardiac ventricular function. A highly-accelerated 2.5-minute sparse MR protocol was developed for a continuous acquisition of cardiac images through multiple cardiac and respiratory cycles. The heart displacement along respiration was extracted using a 3D image deformation algorithm, and this information was used to cluster the acquired data into multiple respiratory phases. The proposed approach was tested in 15 healthy volunteers (7 females). Cardiac function parameters, including the end-systolic volume (ESV), end-diastolic volume (EDV), stroke volume (SV), and ejection fraction (EF), were measured for the left and right ventricle in both end-expiration and end-inspiration. Although with the proposed 5D cardiac MRI, there were no significant differences (p > 0.05, t-test) between end-expiration and end-inspiration measurements of the cardiac function in volunteers, incremental respiratory motion parameters that were derived from 3D motion tracking, such as the depth, expiration and inspiration distribution, correlated (p < 0.05, correlation coefficient, Mann-Whitney) with those volume-based parameters of cardiac function and varied between genders. The obtained initial results suggested that this new approach allows evaluation of cardiac function during specific respiratory phases. Thus, it can enable investigation of effects related to respiratory variability and better assessment of cardiac function for studying respiratory and/or cardiac dysfunction.

Highly-accelerated self-gated free-breathing 3D cardiac cine MRI: validation in assessment of left ventricular function.

OBJECTIVE: This work presents a highly-accelerated, self-gated, free-breathing 3D cardiac cine MRI method for cardiac function assessment. MATERIALS AND METHODS: A golden-ratio profile based variable-density, pseudo-random, Cartesian undersampling scheme was implemented for continuous 3D data acquisition. Respiratory self-gating was achieved by deriving motion signal from the acquired MRI data. A multi-coil compressed sensing technique was employed to reconstruct 4D images (3D+time). 3D cardiac cine imaging with self-gating was compared to bellows gating and the clinical standard breath-held 2D cine imaging for evaluation of self-gating accuracy, image quality, and cardiac function in eight volunteers. Reproducibility of 3D imaging was assessed. RESULTS: Self-gated 3D imaging provided an image quality score of 3.4 ± 0.7 vs 4.0 ± 0 with the 2D method (p = 0.06). It determined left ventricular end-systolic volume as 42.4 ± 11.5 mL, end-diastolic volume as 111.1 ± 24.7 mL, and ejection fraction as 62.0 ± 3.1%, which were comparable to the 2D method, with bias ± 1.96 × SD of -0.8 ± 7.5 mL (p = 0.90), 2.6 ± 3.3 mL (p = 0.84) and 1.4 ± 6.4% (p = 0.45), respectively. CONCLUSION: The proposed 3D cardiac cine imaging method enables reliable respiratory self-gating performance with good reproducibility, and provides comparable image quality and functional measurements to 2D imaging, suggesting that self-gated, free-breathing 3D cardiac cine MRI framework is promising for improved patient comfort and cardiac MRI scan efficiency.

Assessment of Left Ventricular Enlargement at Multidetector Computed Tomography.

PURPOSE: Because left ventricular (LV) enlargement (LVE) is indicative of an array of cardiac pathologies, including cardiomyopathic, ischemic, and valvular heart diseases, it is important to recognize it early in the course of these diseases. The recognition of LVE on nongated contrast-enhanced computed tomography (CT) scans should be facilitated by the availability of a dimensional index. To our knowledge, no CT index of LVE has been proposed. Therefore, the study aimed to define whether the maximum LV diameter (LVd) measured on nongated multidetector computed tomography can identify LVE when referencing echocardiography as the diagnostic standard. MATERIALS AND METHODS: The patient population consisted of 438 consecutive patients who had a contrast-enhanced, nongated 16- or 64-detector CT of the chest for evaluation of pulmonary embolism or aortic dissection between January 2006 and March 2008. One hundred fifty-five patients in this group also had an echocardiogram within 2 months of the CT study. The maximum LV cavity size, septal to lateral wall dimension, was measured perpendicularly to the long axis of the left ventricle on the axial CT scans by 2 observers blinded to the echocardiography data.An receiver operating characteristic analysis was performed to identify a highly specific cutoff for the diagnosis of LVE on CT, using echocardiogram as the standard of reference. Interobserver agreement was assessed using Bland-Altman analysis. RESULTS: A total of 84 females and 71 males were evaluated (female to male ratio of 1.09). The mean age for the 155 patients was 58 years. Six percent of these patients had a diagnosis of LVE on 2-dimensional echocardiography. The mean (SEM) LV internal diameter at nongated multidetector computed tomography between the group with normal LV and the group with LVE by echocardiography was 4.4 (0.7) cm for the normal LV and 5.9 (1.2) cm for the dilated LVs (P < 0.0001). With the use of threshold value of LVd of 5.6 cm, a sensitivity of 78%, specificity of 100%, positive likelihood ratio of 113.5, and negative likelihood ratio of 0.22 were calculated. The LVd measurements had an excellent agreement between observers on the Bland-Altman analysis. CONCLUSIONS: Left ventricular enlargement can be reliably identified on nongated contrast-enhanced multidetector CT when the maximum luminal diameter of the LV is greater than 5.6 cm. Nongated contrast-enhanced CT scan can be used to recognize LVE.

Understanding Cost-Effectiveness Analyses: An Explanation Using Three Different Analyses of Lung Cancer Screening.

OBJECTIVE: Cost-effectiveness analyses (CEAs) contribute to informed decision making, at both the practitioner and societal levels; therefore, understanding CEAs is valuable for radiologists. In light of the recently published National Lung Cancer Screening Trial (NLST) CEA, we aim to explain the terminology, methods, and heterogeneity of CEAs. CONCLUSION: We compared the NLST results to two example lung cancer screening CEAs (which do not rely on NLST data). Both examples assessed screening but reached substantially different conclusions.

Mitral Annular and Coronary Artery Calcification Are Associated with Mortality in HIV-Infected Individuals.

BACKGROUND: HIV infection increases cardiovascular risk. Coronary artery calcification (CAC) and mitral annular calcification (MAC) identify patients at risk for cardiovascular disease (CVD). The purpose of this study was to examine the association between MAC, CAC and mortality in HIV-infected individuals. METHODS AND RESULTS: We studied 152 asymptomatic HIV-infected individuals with transthoracic echocardiography (TTE) and computed tomography (CT). MAC was identified on TTE using standardized criteria. Presence of CAC, CAC score and CAC percentiles were determined using the modified Agatston criteria. Mortality data was obtained from the Social Security and National Death Indices (SSDI/NDI). The median age was 49 years; 87% were male. The median duration of HIV was 16 years; 84% took antiretroviral therapy; 64% had an undetectable viral load. CVD risk factors included hypertension (35%), smoking (62%) and dyslipidemia (35%). Twenty-five percent of individuals had MAC, and 42% had CAC. Over a median follow-up of 8 years, 11 subjects died. Subjects with CAC had significantly higher mortality compared to those with MAC only or no MAC. The Harrell's C-statistic of CAC was 0.66 and increased to 0.75 when MAC was added (p = 0.05). MAC, prior CVD, age and HIV viral load were independently associated with higher age- and gender-adjusted CAC percentiles in an adjusted model (p < 0.05 for all). CONCLUSION: In HIV patients, the presence of MAC, traditional risk factors and HIV viral load were independently associated with CAC. Presence of CAC and MAC may be useful in identifying HIV-infected individuals at higher risk for death.

Advances in MR imaging assessment of adults with congenital heart disease.

Many novel cardiac MR sequences can be used for assessment of adult patients with congenital heart disease. Although most of these techniques are still primarily used in the research arena, there are many potential applications in clinical practice. Advanced cardiac MR assessment of myocardial tissue characterization, flow hemodynamics, and myocardial strain are promising tools for diagnostic and prognostic assessment late after repair of congenital heart diseases.

CMR assessment of right ventricular function in patients with combined pulmonary stenosis and insufficiency after correction of tetralogy of Fallot.

BACKGROUND: Tetralogy of Fallot (TOF) is one of the most common types of congenital heart disease and requires prompt surgical correction. Post-correction pulmonary insufficiency (PI) often ensues in adulthood. At times, the PI is accompanied by residual pulmonary stenosis (PS). Little is known regarding right ventricular (RV) function in the setting of combined PS and PI. PURPOSE: To compare cardiac magnetic resonance (CMR) parameters for the assessment of RV function between patients with combined pulmonary stenosis and pulmonary insufficiency (PSPI) and isolated PI following surgical repair of TOF. MATERIAL AND METHODS: Retrospective review of patients with comparable corrected TOF and similar PI was performed. Seventeen patients (median age, 24 years; range, 10-52 years) had combined PSPI and 30 patients (median age, 30 years; range, 6-70 years) had isolated PI. Cine magnetic resonance (MR) images (Philips Medical Systems, Best, The Netherlands) in the short-axis plane were used to calculate end-systolic, end-diastolic, and stroke volumes (RVESV, RVEDV, RVSV) and to measure RV wall thickness. Velocity-encoded cine MR images were used to measure pulmonary regurgitation fraction (PRF) by calculating the ratio of backward flow and total forward flow, obtained from the main pulmonary flow analysis. Peak pressure gradient across the pulmonary valve was obtained from spectral Doppler echocardiography. RESULTS: RVEF was 51 ± 8% in the PSPI patients and 39 ± 11%, in the patients with isolated PI (P = 0.001). Additionally, RV wall thickness was 5.2 ± 0.8 mm in the PSPI patients compared to 2.6 ± 0.9 mm in the isolated PI patients (P = 0.001). RVESVi and RVEDVi were significantly lower (P < 0.05) in patients with combined PSPI (60 ± 21 mL/m(2), 121 ± 35 mL/m(2), respectively) compared to the patients with isolated PI (95 ± 48 mL/m(2), 152 ± 61 mL/m(2), respectively). CONCLUSION: RV function is preserved in patients with PSPI when compared to patients with PI following surgical repair of TOF.

Collateral flow measurement by phase-contrast magnetic resonance imaging for the assessment of systemic venous baffle patency after atrial switch repair for transposition of the great arteries.

PURPOSE: We aimed to describe and compare azygos vein flow patterns of patients with obstructed and unobstructed systemic venous baffle after atrial switch repair for d-transposition of the great arteries (TGA). We hypothesized that phase-contrast magnetic resonance imaging would enable characterization of retrograde collateral flow across the azygos vein in cases of systemic venous baffle obstruction. MATERIALS AND METHODS: This is a retrospective, cross-sectional study. Twelve patients with atrial switch repair for TGA were examined. Azygos flow index was measured with phase-contrast magnetic resonance imaging; comparison was made between patients with documented systemic venous baffle obstruction (n=3) and a control group of patients without baffle obstruction (n=9). RESULTS: Patients with systemic venous baffle obstruction had a distinctive azygos flow pattern that was retrograde and an increased amount of azygos flow compared with patients without obstruction [median (range), -436 (-455/-399) vs. 103 (51/125) mL/min/m2; P=0.01]. CONCLUSIONS: Patients with systemic venous baffle obstruction have a characteristic collateral flow across the azygos vein. Azygos vein flow measurement may be used for the assessment of baffle patency in patients after atrial switch repair for TGA. However, diagnostic accuracy needs to be tested in a larger population.

4D flow CMR in assessment of valve-related ascending aortic disease.

Blood flow imaging with 3-dimensional time-resolved, phase-contrast cardiac magnetic resonance (4-dimensional [4D] Flow) is an innovative and visually appealing method for studying cardiovascular disease that allows quantification of important secondary vascular parameters including wall shear stress. The hypothesis of this pilot study is that 4D Flow will become a powerful tool for characterizing the relationship of aortic valve-related flow dynamics, especially with bicuspid aortic valve (BAV), and progression of ascending aortic (AsAo) dilation. We identified 46 patients previously studied with 4D Flow: tricuspid aortic valve patients without valvular disease (n = 20), and BAV patients with either normal flow (n = 7) or eccentric systolic jets resulting in abnormal right-handed helical AsAo flow (n = 19). The subgroup of patients with BAV and eccentric systolic AsAo blood flow was found to have significantly and asymmetrically elevated wall shear stress. This increased hemodynamic burden may place them at risk for AsAo aneurysm.

Cardiovascular MRI for the assessment of heart failure: focus on clinical management and prognosis.

Cardiovascular MR (CMR) has an emerging role in the noninvasive diagnostic assessment of heart failure (HF). Different imaging sequences allow for a detailed assessment of cardiac morphology, function, myocardial perfusion, tissue characterization, and blood flow measurement. This article reviews the key applications of CMR in HF, with special focus on how CMR may influence the diagnostic and therapeutic approach of HF patients.

Velocity-encoded cine MR imaging in aortic coarctation: functional assessment of hemodynamic events.

Velocity-encoded cine magnetic resonance (MR) imaging is becoming the modality of choice for the clinical evaluation of aortic coarctation, a congenital narrowing of the thoracic aorta, in which a functional assessment of hemodynamic obstruction is as important as anatomic delineation. A flow-sensitive phase-contrast technique, velocity-encoded cine MR imaging is based on the principle that moving protons change phase in proportion to their velocity. Because it enables precise hemodynamic characterization, the technique is especially useful for evaluating the severity of aortic coarctation. By enabling a qualitative assessment of the presence and direction of collateral circulation, velocity-encoded cine MR imaging provides information about the presence and severity of obstruction. It also allows accurate quantitation of key hemodynamic parameters such as flow velocity, flow volume, and pressure gradients across the coarctation-functional information that is clinically useful for both preoperative planning and postinterventional monitoring. The results of recent experience indicate that velocity-encoded cine MR imaging also may be applicable for the detection of recurrent stenosis after stent placement or angioplasty.