Diastology with Cardiac MRI: A Practical Guide.

Diastolic filling of the ventricle is a complex interplay of volume and pressure, contingent on active energy-dependent myocardial relaxation and myocardial stiffness. Abnormal diastolic function is the hallmark of the clinical entity of heart failure with preserved ejection fraction (HFpEF), which is now the dominant type of heart failure and is associated with significant morbidity and mortality. Although echocardiography is the current first-line imaging modality used in evaluation of diastolic function, cardiac MRI (CMR) is emerging as an important technique. The principal role of CMR is to categorize the cause of diastolic dysfunction (DD) and distinguish other entities that manifest similarly to HFpEF, particularly infiltrative and pericardial disorders. CMR also provides prognostic information and risk stratification based on late gadolinium enhancement and parametric mapping techniques. Advances in hardware, sequences, and postprocessing software now enable CMR to diagnose and grade DD accurately, a role traditionally assigned to echocardiography. Two-dimensional or four-dimensional velocity-encoded phase-contrast sequences can measure flow and velocities at the mitral inflow, mitral annulus, and pulmonary veins to provide diastolic functional metrics analogous to those at echocardiography. The commonly used cine steady-state free-precession sequence can provide clues to DD including left ventricular mass, left ventricular filling curves, and left atrial size and function. MR strain imaging provides information on myocardial mechanics that further aids in diagnosis and prognosis of diastolic function. Research sequences such as MR elastography and MR spectroscopy can help evaluate myocardial stiffness and metabolism, respectively, providing additional insights on diastolic function. The authors review the physiology of diastolic function, mechanics of diastolic heart failure, and CMR techniques in the evaluation of diastolic function. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Cardiac Magnetic Resonance Fingerprinting: Potential Clinical Applications.

PURPOSE OF REVIEW: Cardiac magnetic resonance fingerprinting (cMRF) has developed as a technique for rapid, multi-parametric tissue property mapping that has potential to both improve cardiac MRI exam efficiency and expand the information captured. In this review, we describe the cMRF technique, summarize technical developments and in vivo reports, and highlight potential clinical applications. RECENT FINDINGS: Technical developments in cMRF continue to progress rapidly, including motion compensated reconstruction, additional tissue property quantification, signal time course analysis, and synthetic LGE image generation. Such technical developments can enable simplified CMR protocols by combining multiple evaluations into a single protocol and reducing the number of breath-held scans. cMRF continues to be reported for use in a range of pathologies; however barriers to clinical implementation remain. Technical developments are described in this review, followed by a focus on potential clinical applications that they may support. Clinical translation of cMRF could shorten protocols, improve CMR accessibility, and provide additional information as compared to conventional cardiac parametric mapping methods. Current needs for clinical implementation are discussed, as well as how those needs may be met in order to bring cMRF from its current research setting to become a viable tool for patient care.

Reference Ranges, Diagnostic and Prognostic Utility of Native T1 Mapping and Extracellular Volume for Cardiac Amyloidosis: A Meta-Analysis.

BACKGROUND: Cardiac MRI is central to the evaluation of cardiac amyloidosis (CA). Native T1 mapping and extracellular volume (ECV) are novel MR techniques with evolving utility in cardiovascular diseases, including CA. PURPOSE: To perform a meta-analysis of the diagnostic and prognostic data of native T1 mapping and ECV techniques for assessing CA. STUDY TYPE: Systematic review and meta-analysis. POPULATION: In all, 3520 patients including 1539 with CA from 22 studies retrieved following systematic search of Pubmed, Cochrane, and Embase. FIELD STRENGTH/SEQUENCE: 1.5T or 3.0T/modified Look-Locker inversion recovery (MOLLI) or shortened MOLLI (shMOLLI) sequences. ASSESSMENT: Meta-analysis was performed for all CA and for light-chain (AL) and transthyretin (ATTR) subtypes. Thresholds were calculated to classify native T1 and ECV values as not suggestive, indeterminate, or suggestive of CA. STATISTICAL ANALYSIS: Area under the receiver-operating characteristic curves (AUCs) and hazards ratios (HRs) with 95% confidence intervals (95% CI) were pooled using random-effects models and Open-Meta(Analyst) software. RESULTS: Six studies were diagnostic, 16 studies reported T1 and ECV values to determine reference range, and six were prognostic. Pooled AUCs (95% CI) for diagnosing CA were 0.92 (0.89-0.96) for native T1 mapping and 0.96 (0.93-1.00) for ECV, with similarly high detection rates for AL- and ATTR-CA. Based on the pooled values of native T1 and ECV in CA and control subjects, the thresholds that suggested the absence, indeterminate, or presence of CA were identified as <994 msec, 994-1073 msec, and >1073 msec, respectively, for native T1 at 1.5T. Pooled HRs (95% CI) for predicting all-cause mortality were 1.15 (1.08-1.22) for native T1 mapping as a continuous parameter, 1.19 (1.01-1.40) for ECV as a continuous parameter, and 4.93 (2.64-9.20) for ECV as a binary threshold. DATA CONCLUSION: Native T1 mapping and ECV had high diagnostic performance and predicted all-cause mortality in CA. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 2.

Defining the Reference Range for Left Ventricular Strain in Healthy Patients by Cardiac MRI Measurement Techniques: Systematic Review and Meta-Analysis.

BACKGROUND. Echocardiography is the primary noninvasive technique for left ventricular (LV) strain measurement. MRI has potential advantages, although reference ranges and thresholds to differentiate normal from abnormal left ventricular global longitudinal strain (LVGLS), left ventricular global circumferential strain (LVGCS), and left ventricular global radial strain (LVGRS) are not yet established. OBJECTIVE. The purpose of our study was to determine the mean and lower limit of normal (LLN) of MRI-derived LV strain measurements in healthy patients and explore factors potentially influencing these measurements. EVIDENCE ACQUISITION. PubMed, Embase, and Cochrane Library databases were searched for studies published through January 1, 2020, that reported MRI-derived LV strain measurements in at least 30 healthy individuals. Mean and LLN measurements of LV strain were pooled using random-effects models overall and for studies stratified by measurement method (feature tracking [FT] or tagging). Additional subgroup and meta-regression analyses were performed. EVIDENCE SYNTHESIS. Twenty-three studies with a total of 1782 healthy subjects were included. Pooled means and LLNs for all studies were -18.6% (95% CI, -19.5% to -17.6%) and -13.3% (-13.9% to 12.7%) for LVGLS, -21.0% (-22.4% to -19.6%) and -15.6% (-17.0% to -14.3%) for LVGCS, and 38.7% (30.5-46.9%) and 20.6% (15.1-26.1%) for LVGRS. Pooled means and LLNs for LVGLS by strain measurement method were -19.4% (95% CI, -20.6% to -18.1%) and -13.1% (-14.2% to -12.0%) for FT and -15.6% (-16.2% to -15.1%) and -13.1% (-14.1% to -12.2%) for tagging. A later year of study publication, increasing patient age, and increasing body mass index were associated with more negative mean LVGLS values. An increasing LV end-diastolic volume index was associated with less negative mean LVGLS values. No factor was associated with LLN of LVGLS. CONCLUSION. We determined the pooled means and LLNs, with associated 95% CIs, for LV strain by cardiac MRI to define thresholds for normal, abnormal, and borderline strain in healthy patients. The method of strain measurement by MRI affected the mean LVGLS. No factor affected the LLN of LVGLS. CLINICAL IMPACT. This meta-analysis lays a foundation for clinical adoption of MRI-derived LV strain measurements, with management implications in both healthy patients and patients with various disease states.

Predictors of Cardiac Implantable Electronic Device Artifact on Cardiac MRI: The Utility of a Device Related Score.

PURPOSE: Cardiac magnetic resonance imaging (CMR) image quality can be degraded by artifact in patients with cardiac implantable electronic devices (CIED). We aimed to establish a clinical risk score, so patient selection for diagnostic CMR could be optimised. METHODS: In this retrospective cohort study, CMRs performed for clinical use in subjects with CIED from January 2016 to May 2019 were reviewed. Subject anthropometry, CIED generator/lead specifications and pre-scan chest X-ray (CXR) measurements were collected. Generator-related artifact size was measured on axial steady state free precession images. Interpretability of late gadolinium enhancement (LGE) imaging was performed based on a three-grade visual score attributed to each of 17 myocardial segments. RESULTS: Fifty-seven (57) patients (59±16 years, 74% male) fitted the inclusion criteria. Artifact precluded left ventricle (LV) evaluation (≥5 segments) in 17 (30%). Artifact was more common with implantable cardioverter-defibrillators, related to generator volume, mass, height, width, thickness, and area, along with right ventricular (RV) lead length and diameter (all p<0.05). Artifact was associated with distance from generator to LV apex, generator to RV lead tip and shortest distance from generator to heart on CXR (all p<0.05). On multivariable regression modelling, RV lead diameter (OR 5.861, 95% CI 1.866-18.407, p=0.002) and distance from generator to LV apex (OR 0.693, 95% CI 0.511-0.940, p=0.019) were independent predictors of artifact. Multivariable predictors were used to develop Device Related CMR Artifact Prediction Score (DR-CAPS), where all patients with DR-CAPS=0 had fully interpretable LGE imaging. CONCLUSION: Simple, readily available measures, such as lead characteristics and pre-scan CXR measures, can stratify patients via an artifact prediction score to optimise selection for diagnostic CMR.

Standardized cardiovascular magnetic resonance imaging (CMR) protocols: 2020 update.

This document is an update to the 2013 publication of the Society for Cardiovascular Magnetic Resonance (SCMR) Board of Trustees Task Force on Standardized Protocols. Concurrent with this publication, 3 additional task forces will publish documents that should be referred to in conjunction with the present document. The first is a document on the Clinical Indications for CMR, an update of the 2004 document. The second task force will be updating the document on Reporting published by that SCMR Task Force in 2010. The 3rd task force will be updating the 2013 document on Post-Processing. All protocols relative to congenital heart disease are covered in a separate document.The section on general principles and techniques has been expanded as more of the techniques common to CMR have been standardized. A section on imaging in patients with devices has been added as this is increasingly seen in day-to-day clinical practice. The authors hope that this document continues to standardize and simplify the patient-based approach to clinical CMR. It will be updated at regular intervals as the field of CMR advances.

Standardized image interpretation and post-processing in cardiovascular magnetic resonance - 2020 update : Society for Cardiovascular Magnetic Resonance (SCMR): Board of Trustees Task Force on Standardized Post-Processing.

With mounting data on its accuracy and prognostic value, cardiovascular magnetic resonance (CMR) is becoming an increasingly important diagnostic tool with growing utility in clinical routine. Given its versatility and wide range of quantitative parameters, however, agreement on specific standards for the interpretation and post-processing of CMR studies is required to ensure consistent quality and reproducibility of CMR reports. This document addresses this need by providing consensus recommendations developed by the Task Force for Post-Processing of the Society for Cardiovascular Magnetic Resonance (SCMR). The aim of the Task Force is to recommend requirements and standards for image interpretation and post-processing enabling qualitative and quantitative evaluation of CMR images. Furthermore, pitfalls of CMR image analysis are discussed where appropriate. It is an update of the original recommendations published 2013.

A novel machine learning-derived radiotranscriptomic signature of perivascular fat improves cardiac risk prediction using coronary CT angiography.

BACKGROUND: Coronary inflammation induces dynamic changes in the balance between water and lipid content in perivascular adipose tissue (PVAT), as captured by perivascular Fat Attenuation Index (FAI) in standard coronary CT angiography (CCTA). However, inflammation is not the only process involved in atherogenesis and we hypothesized that additional radiomic signatures of adverse fibrotic and microvascular PVAT remodelling, may further improve cardiac risk prediction. METHODS AND RESULTS: We present a new artificial intelligence-powered method to predict cardiac risk by analysing the radiomic profile of coronary PVAT, developed and validated in patient cohorts acquired in three different studies. In Study 1, adipose tissue biopsies were obtained from 167 patients undergoing cardiac surgery, and the expression of genes representing inflammation, fibrosis and vascularity was linked with the radiomic features extracted from tissue CT images. Adipose tissue wavelet-transformed mean attenuation (captured by FAI) was the most sensitive radiomic feature in describing tissue inflammation (TNFA expression), while features of radiomic texture were related to adipose tissue fibrosis (COL1A1 expression) and vascularity (CD31 expression). In Study 2, we analysed 1391 coronary PVAT radiomic features in 101 patients who experienced major adverse cardiac events (MACE) within 5 years of having a CCTA and 101 matched controls, training and validating a machine learning (random forest) algorithm (fat radiomic profile, FRP) to discriminate cases from controls (C-statistic 0.77 [95%CI: 0.62-0.93] in the external validation set). The coronary FRP signature was then tested in 1575 consecutive eligible participants in the SCOT-HEART trial, where it significantly improved MACE prediction beyond traditional risk stratification that included risk factors, coronary calcium score, coronary stenosis, and high-risk plaque features on CCTA (Δ[C-statistic] = 0.126, P < 0.001). In Study 3, FRP was significantly higher in 44 patients presenting with acute myocardial infarction compared with 44 matched controls, but unlike FAI, remained unchanged 6 months after the index event, confirming that FRP detects persistent PVAT changes not captured by FAI. CONCLUSION: The CCTA-based radiomic profiling of coronary artery PVAT detects perivascular structural remodelling associated with coronary artery disease, beyond inflammation. A new artificial intelligence (AI)-powered imaging biomarker (FRP) leads to a striking improvement of cardiac risk prediction over and above the current state-of-the-art.

Non-invasive detection of coronary inflammation using computed tomography and prediction of residual cardiovascular risk (the CRISP CT study): a post-hoc analysis of prospective outcome data.

BACKGROUND: Coronary artery inflammation inhibits adipogenesis in adjacent perivascular fat. A novel imaging biomarker-the perivascular fat attenuation index (FAI)-captures coronary inflammation by mapping spatial changes of perivascular fat attenuation on coronary computed tomography angiography (CTA). However, the ability of the perivascular FAI to predict clinical outcomes is unknown. METHODS: In the Cardiovascular RISk Prediction using Computed Tomography (CRISP-CT) study, we did a post-hoc analysis of outcome data gathered prospectively from two independent cohorts of consecutive patients undergoing coronary CTA in Erlangen, Germany (derivation cohort) and Cleveland, OH, USA (validation cohort). Perivascular fat attenuation mapping was done around the three major coronary arteries-the proximal right coronary artery, the left anterior descending artery, and the left circumflex artery. We assessed the prognostic value of perivascular fat attenuation mapping for all-cause and cardiac mortality in Cox regression models, adjusted for age, sex, cardiovascular risk factors, tube voltage, modified Duke coronary artery disease index, and number of coronary CTA-derived high-risk plaque features. FINDINGS: Between 2005 and 2009, 1872 participants in the derivation cohort underwent coronary CTA (median age 62 years [range 17-89]). Between 2008 and 2016, 2040 patients in the validation cohort had coronary CTA (median age 53 years [range 19-87]). Median follow-up was 72 months (range 51-109) in the derivation cohort and 54 months (range 4-105) in the validation cohort. In both cohorts, high perivascular FAI values around the proximal right coronary artery and left anterior descending artery (but not around the left circumflex artery) were predictive of all-cause and cardiac mortality and correlated strongly with each other. Therefore, the perivascular FAI measured around the right coronary artery was used as a representative biomarker of global coronary inflammation (for prediction of cardiac mortality, hazard ratio [HR] 2·15, 95% CI 1·33-3·48; p=0·0017 in the derivation cohort, and 2·06, 1·50-2·83; p<0·0001 in the validation cohort). The optimum cutoff for the perivascular FAI, above which there is a steep increase in cardiac mortality, was ascertained as -70·1 Hounsfield units (HU) or higher in the derivation cohort (HR 9·04, 95% CI 3·35-24·40; p<0·0001 for cardiac mortality; 2·55, 1·65-3·92; p<0·0001 for all-cause mortality). This cutoff was confirmed in the validation cohort (HR 5·62, 95% CI 2·90-10·88; p<0·0001 for cardiac mortality; 3·69, 2·26-6·02; p<0·0001 for all-cause mortality). Perivascular FAI improved risk discrimination in both cohorts, leading to significant reclassification for all-cause and cardiac mortality. INTERPRETATION: The perivascular FAI enhances cardiac risk prediction and restratification over and above current state-of-the-art assessment in coronary CTA by providing a quantitative measure of coronary inflammation. High perivascular FAI values (cutoff ≥-70·1 HU) are an indicator of increased cardiac mortality and, therefore, could guide early targeted primary prevention and intensive secondary prevention in patients. FUNDING: British Heart Foundation, and the National Institute of Health Research Oxford Biomedical Research Centre.

Teamwork using strain imaging in the echocardiographic assessment of right ventricular systolic function: A cardiac magnetic resonance imaging correlation study.

AIM: The aim of this study was to investigate whether conventional echocardiographic assessment of right ventricular (RV) systolic function can be improved by the addition of RV strain imaging. Additionally, we also aimed to investigate whether dedicated reading sessions and education can improve echocardiographic interpretation of RV systolic function. METHODS: Readers of varying expertise (staff echocardiologists, advanced cardiovascular imaging fellows, sonographers) assessed RV systolic function. In session 1, 20 readers graded RV function of 19 cases, using conventional measures. After dedicated education, in session 2, the same cases were reassessed, with the addition of RV strains. In session 3, 18 readers graded RV function of 20 additional cases, incorporating RV strains. Computer simulations were performed to obtain 230 random teams. RV ejection fraction (RVEF) by cardiac magnetic resonance (CMR) was the reference standard. RESULTS: Correlation between RV GLS and CMR-derived RVEF was moderate: Spearman's rho: 0.70, n = 19, P < 0.001 (first two sessions); 0.55, n = 20, P < 0.05 (third session). Individual readers' assessment moderately correlated with RVEF (Spearman's rho first session: 0.67 ± 0.2; second session: 0.61 ± 0.2; and third session: 0.68 ± 0.09). Team estimates of RV systolic function showed consistently better correlation with RVEF, which were improved further by averaging across all readers. RV strain parameters influenced echocardiographic interpretation, with a net reclassification index of 8.0 ± 3.6% (P = 0.014). CONCLUSIONS: The RV strain parameters showed moderate correlations with CMR-derived RVEF and appropriately influenced echocardiographic interpretation of RV systolic function. "Wisdom of the crowd" applied by averaging echocardiographic assessments of RV systolic function across teams of echocardiography readers, further improved echocardiographic assessment of RV systolic function.

Predictors and Prognostic Significance of Right Ventricular Ejection Fraction in Patients With Ischemic Cardiomyopathy.

BACKGROUND: Decreased right ventricular (RV) ejection fraction (RVEF) portends poor prognosis in patients with ischemic cardiomyopathy, and previous studies have suggested an association between mitral regurgitation (MR) and RVEF. We sought to evaluate this association and whether mitral valve repair or replacement affects the relationship between RV function and mortality. METHODS: We included 588 patients (mean age, 63±11 years; 75% male) with ischemic cardiomyopathy who underwent cardiac magnetic resonance imaging between 2002 and 2008. Baseline characteristics, left ventricular ejection fraction, MR severity, treatment modality, scar burden, and RVEF were assessed. Multivariable linear regression and Cox proportional hazards models were used to assess the association between MR and RVEF and between RVEF and mortality, respectively. RESULTS: After adjustment for age, sex, left ventricular ejection fraction, right bundle-branch block, and RV scar, MR severity was found to be associated independently with RVEF. There were a total of 240 deaths during a median follow-up time of 5.7 years. After multivariable adjustment, every 10% decrease in RVEF was associated with a 17% increased risk of death (P=0.008). Although decreasing RVEF was associated with a poor prognosis in the nonrepair group (hazard ratio, 1.28; 95% confidence interval, 1.12-1.47; P<0.001), it was not associated with death in the mitral valve repair or replacement group (P for interaction=0.046). CONCLUSIONS: MR severity was found to be an independent predictor of RVEF, as were right bundle-branch block, left ventricular ejection fraction, and the presence of RV scar. Decreasing RVEF is associated with increased mortality in patients with ischemic cardiomyopathy; however, this association may be mitigated in patients who undergo mitral valve repair or replacement.

The global cardiovascular magnetic resonance registry (GCMR) of the society for cardiovascular magnetic resonance (SCMR): its goals, rationale, data infrastructure, and current developments.

BACKGROUND: With multifaceted imaging capabilities, cardiovascular magnetic resonance (CMR) is playing a progressively increasing role in the management of various cardiac conditions. A global registry that harmonizes data from international centers, with participation policies that aim to be open and inclusive of all CMR programs, can support future evidence-based growth in CMR. METHODS: The Global CMR Registry (GCMR) was established in 2013 under the auspices of the Society for Cardiovascular Magnetic Resonance (SCMR). The GCMR team has developed a web-based data infrastructure, data use policy and participation agreement, data-harmonizing methods, and site-training tools based on results from an international survey of CMR programs. RESULTS: At present, 17 CMR programs have established a legal agreement to participate in GCMR, amongst them 10 have contributed CMR data, totaling 62,456 studies. There is currently a predominance of CMR centers with more than 10 years of experience (65%), and the majority are located in the United States (63%). The most common clinical indications for CMR have included assessment of cardiomyopathy (21%), myocardial viability (16%), stress CMR perfusion for chest pain syndromes (16%), and evaluation of etiology of arrhythmias or planning of electrophysiological studies (15%) with assessment of cardiomyopathy representing the most rapidly growing indication in the past decade. Most CMR studies involved the use of gadolinium-based contrast media (95%). CONCLUSIONS: We present the goals, mission and vision, infrastructure, preliminary results, and challenges of the GCMR. TRIAL REGISTRATION: Identification number on ClinicalTrials.gov: NCT02806193 . Registered 17 June 2016.

Coronary artery disease detected by coronary computed tomography angiography in adult survivors of childhood Hodgkin lymphoma.

BACKGROUND: Survivors of Hodgkin lymphoma (HL) have significant cardiovascular risk and require long-term surveillance. The current study assessed the prevalence of coronary artery disease (CAD) by coronary computed tomography angiography (CCTA) in adult survivors of childhood HL. METHODS: Thirty-one survivors of HL, 13 of whom (42%) were treated with radiotherapy (RT) only and 18 of whom (58%) were treated with multimodal therapy, underwent CCTA, echocardiography, electrocardiography (ECG), and treadmill stress testing. Obstructive CAD was defined as ≥50% occlusion of the left main or ≥70% occlusion of the left anterior descending, left circumflex, or right coronary arteries on CCTA. Echocardiograms with resting wall motion abnormalities or an ejection fraction <50%; ECGs with Q waves, ST abnormalities without Q waves, or T-wave abnormalities without Q waves; and a J-point depression of ≥1 mm with a horizontal or downsloping ST segment on stress testing were considered abnormal. RESULTS: The prevalence of disease in participants (median age, 40 years [range, 26 years-55 years]; median time from cancer diagnosis, 24 years [range, 17 years-39 years]) was 39%, with 39 plaques detected among 12 survivors. Three participants (10%) treated with RT only had 4 obstructive lesions; 9 patients (29%; 5 of whom were treated with RT only and 4 of whom were treated with multimodal therapy) had nonobstructive lesions. Approximately 15% of lesions involved the left main, 21% involved the proximal left anterior descending, 18% involved the proximal right coronary, and 13% involved the proximal left circumflex arteries. Of the 12 participants found to have CAD by CCTA, 7 had a positive ECG, 1 had a positive echocardiogram, and 1 had a positive stress test. CONCLUSIONS: CCTA identified CAD in a substantial percentage of survivors of HL and may be an effective screening modality for this population.

Is there a role for diastolic function assessment in era of delayed enhancement cardiac magnetic resonance imaging?: a multimodality imaging study in patients with advanced ischemic cardiomyopathy.

UNLABELLED: Cardiac magnetic resonance (CMR) identifies important prognostic variables in ischemic cardiomyopathy (ICM) patients such as left ventricular (LV) volumes, LV ejection fraction (LVEF), peri-infarct zone, and myocardial scar burden (MSB). It is unknown whether Doppler-based diastolic dysfunction (DDF) retains its prognostic value in ICM patients, in the context of current imaging, medical, and device therapies. METHODS: Diastolic function was evaluated in ICM patients (LVEF ≤ 40% and ≥ 70% stenosis in ≥ 1 coronary artery) who underwent transthoracic echocardiogram and delayed hyperenhancement CMR studies within 7 days. The association of DDF with the combined end point was assessed after risk-adjustment using Cox proportional hazards models. RESULTS: A total of 360 patients with severe LV dysfunction (LVEF = 24 ± 9%) and extensive MSB (31 ± 17%) were evaluated; DDF was present in all patients (stage 1%-44%, stage 2%-25%, stage 3%-31%). There were 130 events (124 deaths and 6 heart transplants) over a median follow-up of 5.8 years (IQR, 3.7-7.4 years). On multivariable analysis, DDF > stage 1 (HR, 1.37; P = .007) was associated with the combined end-point, independent of clinical risk score (HR, 2.40; P < .0001), implantable cardioverter defibrillator implantation (HR, 0.60; P = .009), incomplete revascularization (HR, 1.32; P = .003), mitral regurgitation (HR, 3.37; P = .01), peri-infarct zone area (HR, 1.04; P = 0.02), and MSB (HR, 1.02; P = .01). DDF had incremental prognostic value for the combined end-point (model χ(2) increased from 89 to 95, P = .02). CONCLUSION: DDF is a powerful predictor of mortality in ICM patients with significant LV dysfunction, independent of clinical and CMR data. DDF assessment provides incremental value, improving risk stratification.

Clinical diagnosis and management of large vessel vasculitis: Takayasu arteritis.

Takayasu arteritis (TA) is 1 of the 2 main causes of large vessel vasculitides (LVV), giant cell arteritis being the other. LVV can also develop in various other systemic diseases. In TA, a wide variety of symptoms result from vascular stenoses, occlusions, and dilation. Aneurysms may develop and may occasionally dissect or rupture. Disease activity can sometimes be difficult to assess clinically. Diagnostic modalities also have their shortcomings. Often, acute phase reactants do not accurately detect disease activity. Available vascular imaging modalities may be acceptable in defining vascular anatomy, but are notoriously inaccurate in delineating vascular inflammation. Glucocorticoids remain the cornerstone of therapy in TA, in spite of foreseeable long term side effects. In addition, several steroid-sparing agents are also being used, often based on promising results from small uncontrolled studies. Rarely, endovascular revascularization procedures are necessary. Resection of critical-sized aortic aneurysms and repair of aortic dissections are occasionally warranted as lifesaving procedures. The long term outcome of surgical intervention is often unfavorable and relapses are not uncommon. In addition to TA, other less commonly encountered causes of LVV are also briefly discussed in this review.

Clinical diagnosis and management of large vessel vasculitis: giant cell arteritis.

Large vessel vasculitis (LVV) covers a spectrum of primary vasculitides predominantly affecting the aorta and its major branches. The two main subtypes are giant cell arteritis (GCA) and Takayasu arteritis (TA). Less commonly LVV occurs in various other diseases. Clinical manifestations result from vascular stenosis, occlusion, and dilation, sometimes complicated by aneurysm rupture or dissection. Occasionally LVV is discovered unexpectedly on pathological examination of a resected aortic aneurysm. Clinical evaluation is often unreliable in determining disease activity. Moreover, the diagnostic tools are imperfect. Acute phase reactants can be normal at presentation and available imaging modalities are more reliable in delineating vascular anatomy than in providing reliable information on degree of vascular inflammation. Glucocorticoids are the mainstay of therapy of LVV. Patients may develop predictable adverse effects from long-term glucocorticoid use. Several steroid-sparing agents have also shown some promise and are currently in use. Endovascular revascularization procedures and open surgical treatment for aneurysms and dissections are sometimes necessary, but results are not always favorable and relapses are common. This article, the first in a series of two, will be devoted to GCA and isolated (idiopathic) aortitis, while TA will be covered in detail in the next article.

Novel contouring method for optimizing MRI flow quantification in patients with aortic valve disease.

Optimizing MRI aortic flow quantification is crucial for accurate assessment of valvular disease severity. In this study, we sought to evaluate the accuracy of a novel method of contouring systolic aortic forward flow in comparison to standard contouring methods at various aortic levels. The study included a cohort of patients with native aortic valve (AoV) disease and a small control group referred to cardiac MRI over a 1-year period. Inclusion criteria included aortic flow quantification at aortic valve and one additional level, and no or trace mitral regurgitation (MR) documented both by the MRI AND an echocardiogram done within a year. In addition to flow quantification with standard contouring (SC), a novel Selective Systolic Contouring (SSC) method was performed at aortic valve level, contouring the area demarcated by the AoV leaflets in systole. The bias in each technique's estimate of aortic forward flow was calculated as the mean difference between aortic forward flow and left ventricular stroke volume (LV SV). 98 patients (mean age 56, 71% male) were included: 33 with tricuspid and 65 with congenitally abnormal (bicuspid or unicuspid) AoV. All methods tended to underestimate aortic forward flow, but the bias was smallest with the SSC method (p < 0.001). Therefore, SSC yielded the lowest estimates of mitral regurgitant volume (4.8 ml) and regurgitant fraction (3.9%) (p < 0.05). SSC at AoV level better approximates LV SV in our cohort, and may provide more accurate quantitative assessment of both aortic and mitral valve function.