Improved detection of cardiac sarcoidosis using magnetic resonance with myocardial T2 mapping

Multiparametric Mapping via Cardiovascular Magnetic Resonance in the Risk Stratification of Ventricular Arrhythmias and Sudden Cardiac Death

Risk stratification for malignant ventricular arrhythmias and sudden cardiac death is a daunting task for physicians in daily practice. Multiparametric mapping sequences obtained via cardiovascular magnetic resonance imaging can improve the risk stratification for malignant ventricular arrhythmias by unveiling the presence of pathophysiological pro-arrhythmogenic processes. However, their employment in clinical practice is still restricted. The present review explores the current evidence supporting the association between mapping abnormalities and the risk of ventricular arrhythmias in several cardiovascular diseases. The key message is that further clinical studies are needed to test the additional value of mapping techniques beyond conventional cardiovascular magnetic resonance imaging for selecting patients eligible for an implantable cardioverter defibrillator.

Cardiac Sarcoidosis

Cardiac involvement is a major cause of morbidity and mortality in patients with sarcoidosis. It is important to distinguish between clinical manifest diseases from clinically silent diseases. Advanced cardiac imaging studies are crucial in the diagnostic pathway. In suspected isolated cardiac sarcoidosis, it's key to rule out alternative diagnoses. Therapeutic options can be divided into immunosuppressive agents, guideline-directed medical therapy, antiarrhythmic medications, device/ablation therapy, and heart transplantation.

Cardiac MR Fingerprinting: Overview, Technical Developments, and Applications

Cardiovascular magnetic resonance (CMR) is an established imaging modality with proven utility in assessing cardiovascular diseases. The ability of CMR to characterize myocardial tissue using T1 - and T2 -weighted imaging, parametric mapping, and late gadolinium enhancement has allowed for the non-invasive identification of specific pathologies not previously possible with modalities like echocardiography. However, CMR examinations are lengthy and technically complex, requiring multiple pulse sequences and different anatomical planes to comprehensively assess myocardial structure, function, and tissue composition. To increase the overall impact of this modality, there is a need to simplify and shorten CMR exams to improve access and efficiency, while also providing reproducible quantitative measurements. Multiparametric MRI techniques that measure multiple tissue properties offer one potential solution to this problem. This review provides an in-depth look at one such multiparametric approach, cardiac magnetic resonance fingerprinting (MRF). The article is structured as follows. First, a brief review of single-parametric and (non-Fingerprinting) multiparametric CMR mapping techniques is presented. Second, a general overview of cardiac MRF is provided covering pulse sequence implementation, dictionary generation, fast k-space sampling methods, and pattern recognition. Third, recent technical advances in cardiac MRF are covered spanning a variety of topics, including simultaneous multislice and 3D sampling, motion correction algorithms, cine MRF, synthetic multicontrast imaging, extensions to measure additional clinically important tissue properties (proton density fat fraction, T2 *, and T1ρ ), and deep learning methods for image reconstruction and parameter estimation. The last section will discuss potential clinical applications, concluding with a perspective on how multiparametric techniques like MRF may enable streamlined CMR protocols. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 1.

Real-Life Utilization of Criteria Guidelines for Diagnosis of Cardiac Sarcoidosis (CS)

Despite the increasing recognition of cardiac involvement in systemic sarcoidosis, the diagnosis of cardiac sarcoidosis (CS) remains challenging. Our aim is to present a comprehensive, retrospective case series of CS patients, focusing on the current diagnostic guidelines and management of this life-threatening condition. In our case series, patient data were collected retrospectively, including hospital admission records and rheumatology and cardiology clinic visit notes, detailing demographic, clinical, laboratory, pathology, and imaging studies, as well as cardiac devices and prescribed medications. Cases were divided into definite and probable CS based on the 2014 Heart Rhythm Society guidelines as well as presumed CS based on imaging criteria and clinical findings. Overall, 19 CS patients were included, 17 of whom were diagnosed with probable or presumed CS based on cardiac magnetic resonance imaging (CMR) and/or cardiac positron emission tomography using 18F-Fluorodeoxyglucose (PET-FDG) without supporting endomyocardial biopsy (EMB). The majority of CS patients were male (53%), with a mean age of 52.9 ± 11.8, with CS being the initial manifestation of sarcoidosis in 63% of cases. Most patients presented with high-grade AVB (63%), followed by heart failure (42%) and ventricular tachyarrhythmia (VT) (26%). This case series highlights the significance of utilizing updated diagnostic criteria relying on CMR and PET-FDG given that cardiac involvement can be the initial manifestation of systemic sarcoidosis, requiring prompt diagnosis and treatment to prevent morbidity and mortality.

Diagnosis of cardiac sarcoidosis: histological evidence vs. imaging

INTRODUCTION

The prognosis for cardiac sarcoidosis (CS) remains unfavorable. Although early and accurate diagnosis is crucial, the low detection rate of endomyocardial biopsy makes accurate diagnosis challenging.

AREAS COVERED

The Heart Rhythm Society (HRS) consensus statement and the Japanese Circulation Society (JCS) guidelines are two major diagnostic criteria for the diagnosis of CS. While the requirement of positive histology for the diagnosis in the HRS criteria can result in overlooked cases, the JCS guidelines advocate for a group of 'clinical' diagnoses based on advanced imaging, including cardiovascular magnetic resonance and 18F-fluorodeoxyglucose positron emission tomography, which do not require histological evidence. Recent studies have supported the usefulness of clinical diagnosis of CS. However, other evidence suggests that clinical CS may sometimes be inaccurate. This article describes the advantages and disadvantages of the current diagnostic criteria for CS, and typical imaging and clinical courses.

EXPERT OPINION

The diagnosis of clinical CS has been made possible by recent developments in multimodality imaging. However, it is still crucial to look for histological signs of sarcoidosis in other organs in addition to the endomyocardium. Additionally, phenotyping based on clinical manifestations such as heart failure, conduction abnormality or ventricular arrhythmia, and extracardiac abnormalities is clinically significant.

Cardiac magnetic resonance of hypertrophic heart phenotype: A review

Hypertrophic heart phenotype is characterized by an abnormal left ventricular (LV) thickening. A hypertrophic phenotype can develop as adaptive response in many different conditions such as aortic stenosis, hypertension, athletic training, infiltrative heart muscle diseases, storage disorders and metabolic disorders. Hypertrophic cardiomyopathy (HCM) is the most frequent primary cardiomyopathy (CMP) and a genetical cause of cardiac hypertrophy. It requires the exclusion of any other cause of LV hypertrophy. Cardiac magnetic resonance (CMR) is a comprehensive imaging technique that allows a detailed evaluation of myocardial diseases. It provides reproducible measurements and myocardial tissue characterization. In clinical practice CMR is increasingly used to confirm the presence of ventricular hypertrophy, to detect the underlying cause of the phenotype and more recently as an efficient prognostic tool. This article aims to provide a detailed overview of the applications of CMR in the setting of hypertrophic heart phenotype and its role in the diagnostic workflow of such condition.

Imaging of metabolic and overload disorders in tissues and organs

Metabolic and overload disorders are a heterogeneous group of relatively uncommon but important diseases. While imaging plays a key role in the early detection and accurate diagnosis in specific organs with a pivotal role in several metabolic pathways, most of these diseases affect different tissues as part of a systemic syndromes. Moreover, since the symptoms are often vague and phenotypes similar, imaging alterations can present as incidental findings, which must be recognized and interpreted in the light of further biochemical and histological investigations. Among imaging modalities, MRI allows, thanks to its multiparametric properties, to obtain numerous information on tissue composition, but many metabolic and accumulation alterations require a multimodal evaluation, possibly using advanced imaging techniques and sequences, not only for the detection but also for accurate characterization and quantification. The purpose of this review is to describe the different alterations resulting from metabolic and overload pathologies in organs and tissues throughout the body, with particular reference to imaging findings.

Challenges of cardiac sarcoidosis

Sarcoidosis is a multisystem granulomatosis of unknown origin, which can involve almost any organ. Most frequently the disease involves the lungs and mediastinal lymph nodes, but it can affect the skin, the eyes, nervous system, the heart, kidneys, joints, muscles, calcium metabolism, and probably any other anecdotical organ involvement. Cardiac sarcoidosis is one of the most challenging involvements, as it can lead to cardiac mortality and morbidity, and also because the diagnosis may be difficult. With no specific symptoms, cardiac sarcoidosis may be difficult to suspect in a patient with no previous extra-cardiac sarcoidosis diagnosis. This manuscript reviews the current knowledge of the diagnosis and decision to treat cardiac sarcoidosis, and illustrates the information with a case presentation of a young adult with no risk factors, no previous diagnosis of sarcoidosis, and with cardiac symptoms impairing his quality of life.

Utilization of Cardiovascular Magnetic Resonance Imaging for Resumption of Athletic Activities Following COVID-19 Infection: An Expert Consensus Document on Behalf of the American Heart Association Council on Cardiovascular Radiology and Intervention Leadership and Endorsed by the Society for Cardiovascular Magnetic Resonance

The global pandemic of COVID-19 caused by infection with SARS-CoV-2 is now entering its fourth year with little evidence of abatement. As of December 2022, the World Health Organization Coronavirus (COVID-19) Dashboard reported 643 million cumulative confirmed cases of COVID-19 worldwide and 98 million in the United States alone as the country with the highest number of cases. Although pneumonia with lung injury has been the manifestation of COVID-19 principally responsible for morbidity and mortality, myocardial inflammation and systolic dysfunction though uncommon are well-recognized features that also associate with adverse prognosis. Given the broad swath of the population infected with COVID-19, the large number of affected professional, collegiate, and amateur athletes raises concern regarding the safe resumption of athletic activity (return to play) following resolution of infection. A variety of different testing combinations that leverage ECG, echocardiography, circulating cardiac biomarkers, and cardiovascular magnetic resonance imaging have been proposed and implemented to mitigate risk. Cardiovascular magnetic resonance in particular affords high sensitivity for myocarditis but has been employed and interpreted nonuniformly in the context of COVID-19 thereby raising uncertainty as to the generalizability and clinical relevance of findings with respect to return to play. This consensus document synthesizes available evidence to contextualize the appropriate utilization of cardiovascular magnetic resonance in the return to play assessment of athletes with prior COVID-19 infection to facilitate informed, evidence-based decisions, while identifying knowledge gaps that merit further investigation.

Utilization of cardiovascular magnetic resonance (CMR) imaging for resumption of athletic activities following COVID-19 infection: an expert consensus document on behalf of the American Heart Association Council on Cardiovascular Radiology and Intervention (CVRI) Leadership and endorsed by the Society for Cardiovascular Magnetic Resonance (SCMR)

The global pandemic of coronavirus disease 2019 (COVID-19) caused by infection with severe acute respiratory suyndrome coronavirus 2 (SARS-CoV-2) is now entering its 4th year with little evidence of abatement. As of December 2022, the World Health Organization Coronavirus (COVID-19) Dashboard reported 643 million cumulative confirmed cases of COVID-19 worldwide and 98 million in the United States alone as the country with the highest number of cases. While pneumonia with lung injury has been the manifestation of COVID-19 principally responsible for morbidity and mortality, myocardial inflammation and systolic dysfunction though uncommon are well-recognized features that also associate with adverse prognosis. Given the broad swath of the population infected with COVID-19, the large number of affected professional, collegiate, and amateur athletes raises concern regarding the safe resumption of athletic activity (return to play, RTP) following resolution of infection. A variety of different testing combinations that leverage the electrocardiogram, echocardiography, circulating cardiac biomarkers, and cardiovascular magnetic resonance (CMR) imaging have been proposed and implemented to mitigate risk. CMR in particular affords high sensitivity for myocarditis but has been employed and interpreted non-uniformly in the context of COVID-19 thereby raising uncertainty as to the generalizability and clinical relevance of findings with respect to RTP. This consensus document synthesizes available evidence to contextualize the appropriate utilization of CMR in the RTP assessment of athletes with prior COVID-19 infection to facilitate informed, evidence-based decisions, while identifying knowledge gaps that merit further investigation.

T2 and T2⁎ mapping and weighted imaging in cardiac MRI

Cardiac imaging is progressing from simple imaging of heart structure and function to techniques visualizing and measuring underlying tissue biological changes that can potentially define disease and therapeutic options. These techniques exploit underlying tissue magnetic relaxation times: T₁, T₂ and T₂*. Initial weighting methods showed myocardial heterogeneity, detecting regional disease. Current methods are now fully quantitative generating intuitive color maps that do not only expose regionality, but also diffuse changes - meaning that between-scan comparisons can be made to define disease (compared to normal) and to monitor interval change (compared to old scans). T₁ is now familiar and used clinically in multiple scenarios, yet some technical challenges remain. T₂ is elevated with increased tissue water - oedema. Should there also be blood troponin elevation, this oedema likely reflects inflammation, a key biological process. T₂* falls in the presence of magnetic/paramagnetic materials - practically, this means it measures tissue iron, either after myocardial hemorrhage or in myocardial iron overload. This review discusses how T₂ and T₂^⁎ imaging work (underlying physics, innovations, dependencies, performance), current and emerging use cases, quality assurance processes for global delivery and future research directions.

T2 mapping in myocardial disease: a comprehensive review

Cardiovascular magnetic resonance (CMR) is considered the gold standard imaging modality for myocardial tissue characterization. Elevated transverse relaxation time (T2) is specific for increased myocardial water content, increased free water, and is used as an index of myocardial edema. The strengths of quantitative T2 mapping lie in the accurate characterization of myocardial edema, and the early detection of reversible myocardial disease without the use of contrast agents or ionizing radiation. Quantitative T2 mapping overcomes the limitations of T2-weighted imaging for reliable assessment of diffuse myocardial edema and can be used to diagnose, stage, and monitor myocardial injury. Strong evidence supports the clinical use of T2 mapping in acute myocardial infarction, myocarditis, heart transplant rejection, and dilated cardiomyopathy. Accumulating data support the utility of T2 mapping for the assessment of other cardiomyopathies, rheumatologic conditions with cardiac involvement, and monitoring for cancer therapy-related cardiac injury. Importantly, elevated T2 relaxation time may be the first sign of myocardial injury in many diseases and oftentimes precedes symptoms, changes in ejection fraction, and irreversible myocardial remodeling. This comprehensive review discusses the technical considerations and clinical roles of myocardial T2 mapping with an emphasis on expanding the impact of this unique, noninvasive tissue parameter.

Current State and Future Directions of Multimodality Imaging in Cardiac Sarcoidosis

Cardiac sarcoidosis (CS) is an increasingly recognized cause of heart failure and arrhythmia. Historically challenging to identify, particularly in the absence of extracardiac sarcoidosis, diagnosis of CS has improved with advancements in cardiac imaging. Recognition as well as management may require interpretation of multiple imaging modalities. Echocardiography may serve as an initial screening study for cardiac involvement in patients with systemic sarcoidosis. Cardiac magnetic resonance imaging (CMR) provides information on diagnosis as well as risk stratification, particularly for ventricular arrhythmia in the setting of late gadolinium enhancement. More recently, ¹⁸F-fluorodeoxyglucose position emission tomography (FDG-PET) has assumed a valuable role in the diagnosis and longitudinal management of patients with CS, allowing for the assessment of response to treatment. Hybrid FDG-PET/CT may also be used in the evaluation of extracardiac inflammation, permitting the identification of biopsy sites for diagnostic confirmation. Herein we examine the approach to diagnosis and management of CS using multimodality imaging via a case-based review.

Myocardial T2 values at 1.5 T by a segmental approach with healthy aging and gender

OBJECTIVES

Our aims were to obtain myocardial regional and global T2 values as a reference for normality for the first time using a GE scanner and to assess their association with physiological variables.

METHODS

One hundred healthy volunteers aged 20-70 years (50% females) underwent cardiovascular magnetic resonance. Basal, mid-ventricular, and apical short-axis slices of the left ventricle were acquired by a multi-echo fast-spin-echo (MEFSE) sequence. Image analysis was performed with a commercially available software package. The T2 value was assessed in all 16 myocardial segments and the global value was the mean.

RESULTS

The global T2 value averaged across all subjects was 52.2 ± 2.5 ms (range: 47.0-59.9 ms). Inter-study, intra-observer, and inter-observer reproducibility was good (coefficient of variation < 5%). 3.6% of the segments was excluded because of artifacts and/or partial-volume effects. Segmental T2 values differed significantly (p < 0.0001), with the lowest value in the basal anterolateral segment (50.0 ± 3.5 ms) and the highest in the apical lateral segment (54.9 ± 5.1 ms). Mean T2 was significantly lower in the basal slice compared to both mid-ventricular and apical slices and in the mid-ventricular slice than in the apical slice. Aging was associated with increased segmental and global T2 values. Females showed higher T2 values than males. T2 values were not correlated to heart rate. A significant inverse correlation was detected between global T2 values and mean wall thickness.

CONCLUSIONS

The optimized MEFSE sequence allows for robust and reproducible quantification of segmental T2 values. Gender- and age-specific segmental reference values must be defined for distinguishing healthy and diseased myocardium.

KEY POINTS

• In healthy subjects, T2 values differ among myocardial segments and are influenced by age and gender. • Normal T2 values in the myocardium, usable as a benchmark by other GE sites, were established.

The usefulness of repeated CMR and FDG PET/CT in the diagnosis of patients with initial possible cardiac sarcoidosis

BACKGROUND

Cardiac sarcoidosis (CS) diagnosis is usually based on advanced imaging techniques and multidisciplinary evaluation. Diagnosis is classified as definite, probable, possible or unlikely. If diagnostic confidence remains uncertain, cardiac imaging can be repeated. The objective is to evaluate the usefulness of repeated cardiac magnetic resonance imaging (CMR) and fluorodeoxyglucose positron emission tomography (FDG PET/CT) for CS diagnosis in patients with an initial "possible" CS diagnosis.

METHODS

We performed a retrospective cohort study in 35 patients diagnosed with possible CS by our multidisciplinary team (MDT), who received repeated CMR and FDG PET/CT within 12 months after diagnosis. Imaging modalities were scored on abnormalities suggestive for CS and classified as CMR+/PET+, CMR+/PET-, CMR-/PET+ and CMR-/PET-. Primary endpoint was final MDT diagnosis of CS.

RESULTS

After re-evaluation, nine patients (25.7%) were reclassified as probable CS and 16 patients (45.7%) as unlikely CS. Two patients started immunosuppressive treatment after re-evaluation. At baseline, eleven patients (31.4%) showed late gadolinium enhancement (LGE) on CMR (CMR+) and 26 (74.3%) patients showed myocardial FDG-uptake (PET+). At re-evaluation, nine patients (25.7%) showed LGE (CMR+), while 16 patients (45.7%) showed myocardial FDG-uptake (PET+). When considering both imaging modalities together, 82.6% of patients with CMR-/PET+ at baseline were reclassified as possible or unlikely CS, while 36.4% of patients with CMR+ at baseline were reclassified as probable CS. Three patients with initial CMR-/PET+ showed LGE at re-evaluation.

CONCLUSION

Repeated CMR and FDG PET/CT may be useful in establishing or rejecting CS diagnosis, when initial diagnosis is uncertain. However, clinical relevance has to be further determined.

T2-weighted short-tau-inversion-recovery imaging reflects disease activity of cardiac sarcoidosis

OBJECTIVE

We investigated the diagnostic performance of semi-quantitative hyperintensity on T2-weighted short-tau-inversion-recovery black-blood (T2W-STIR-BB) images in identifying active cardiac sarcoidosis (CS) in patients, and compared it with that of ¹⁸F-fluoro-2-deoxyglucose positron emission tomography (FDG-PET).

METHODS

This retrospective study included 40 steroid-naive patients (age 63.1±12.9 years, 20 men) diagnosed with CS who underwent both cardiac MRI and FDG-PET imaging. Active CS cases were defined as satisfying at least one of the following criteria for conventional indices: exacerbation of ventricular arrhythmia, newly identified advanced atrioventricular block, greater than 5% decrease in left ventricular ejection fraction on echocardiography, positive finding on gallium-scintigraphy or elevated levels of sarcoidosis-related serum biomarkers. T2W-STIR-BB images were semi-quantitatively analysed using a myocardium-to-spleen ratio (MSR). The diagnostic performance of T2W-STIR-BB and FDG-PET imaging for detecting active CS was investigated.

RESULTS

Thirty-three patients satisfied at least one criterion and were considered as having active CS. Thirty patients (75%) tested positive with T2W-STIR-BB imaging, and 25 patients (63%) tested positive with FDG-PET. The sensitivity, specificity, accuracy, and positive and negative predictive values for identifying active CS by semi-quantitative MSR on T2W-STIR-BB images were 79%, 43%, 73%, 87% and 30%, respectively. These results were statistically comparable to those of FDG-PET (70%, 71%, 70%, 92% and 33%, respectively).

CONCLUSIONS

When using conventional diagnostic indices for active CS as the gold standard, T2W-STIR-BB imaging demonstrated comparable diagnostic performance to that of FDG-PET. The semi-quantitative analysis of high signal intensity on T2W-STIR-BB images using MSR was useful for detection of active CS.

Prevalence of newly diagnosed sarcoidosis in patients with ventricular arrhythmias: a cardiac magnetic resonance and 18F-FDG cardiac PET study

Cardiac sarcoidosis (CS) is known to be associated with ventricular tachycardia (VT); however, most investigations to date have focused on patients with known extra-cardiac sarcoidosis. The presence of CS is typically evaluated using 18F-fluorodeoxyglucose (18F-FDG) uptake on cardiac positron emission tomography (PET) or late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR). In this study, we sought to determine the prevalence of primary CS and the relationship between myocardial 18F-FDG uptake and LGE in patients with VT without known sarcoidosis. We retrospectively identified 67 patients without known sarcoidosis or active ischemic heart disease (i.e. significant ischemic disease that had not been previously revascularized) referred for both CMR and PET for evaluation of VT. Standard cine- and LGE- CMR and cardiac PET protocols were used. Myocardial LGE was defined as signal intensity > 5 SDs above the mean signal intensity of normal myocardium. Cardiac PET images were considered positive if there was focal myocardial 18F-FDG uptake having greater activity than the left ventricular blood pool. 45 patients (67%) had LGE, while only 4 (6%) had myocardial FDG uptake. Nine percent of patients with LGE had FDG-uptake while none without LGE did, and 10% of the cohort had indeterminate FDG uptake presumably from poor dietary preparation. Of those with both FDG uptake and LGE, 3/4 ultimately received a clinical diagnosis of CS. 4.5% of patients without previously known sarcoidosis or active ischemic heart disease presenting with VT have newly diagnosed CS. Detection of CS can be increased using a CMR first approach followed by cardiac PET for patients with non-ischemic LGE.

Arrhythmias in Cardiac Sarcoidosis Bench to Bedside: A Case-Based Review

Cardiac sarcoidosis is a component of an often multiorgan granulomatous disease of still uncertain cause. It is being recognized with increasing frequency, mainly as the result of heightened awareness and new diagnostic tests, specifically cardiac magnetic resonance imaging and ¹⁸F-fluorodeoxyglucose positron emission tomography scans. The purpose of this case-based review is to highlight the potentially life-saving importance of making the early diagnosis of cardiac sarcoidosis using these new tools and to provide a framework for the optimal care of patients with this disease. We will review disease mechanisms as currently understood, associated arrhythmias including conduction abnormalities, and atrial and ventricular tachyarrhythmias, guideline-directed diagnostic criteria, screening of patients with extracardiac sarcoidosis, and the use of pacemakers and defibrillators in this setting. Treatment options, including those related to heart failure, and those which may help clarify disease mechanisms are included.

Same day comparison of PET/CT and PET/MR in patients with cardiac sarcoidosis

BACKGROUND

Inflammatory cardiac disorders, in particular, sarcoidosis, play an important role in left ventricular dysfunction, conduction abnormalities, and arrhythmias. In this study, we compared the imaging characteristics and diagnostic information obtained when patients were imaged sequentially with PET/CT and then with hybrid PET/MRI on the same day following a single 18F-FDG injection.

METHODS

Ten patients with known or suspected sarcoidosis underwent imaging in sequence of (a) 99mTc-MIBI, (b) 18F-FDG with PET/CT, and (c) 18F-FDG with 3T PET/MRI. Images were compared quantitatively by determination of SUVmax and SUV on a voxel by voxel basis, and qualitatively by two experienced observers.

RESULTS

When both platforms were compared quantitatively, similar data for the evaluation of enhanced 18F-FDG uptake were obtained. Qualitatively, there were (1) several instances of normal perfusion with delayed enhancement and/or focal 18F-FDG uptake, (2) comparable enhanced 18F-FDG uptake on PET/CT vs. PET/MRI, and (3) diversity in disease patterns with delayed enhancement only, increased 18F-FDG uptake only, or both.

CONCLUSION

In this limited patient study, PET/CT and PET/MR provided similar diagnostic data for 18F-FDG uptake, and the concurrent acquisition of MR images provided further insight into the disease process.

Prevalence of newly diagnosed sarcoidosis in patients with ventricular arrhythmias: a cardiac magnetic resonance and 18F-FDG cardiac PET study

Cardiac sarcoidosis (CS) is known to be associated with ventricular tachycardia (VT); however, most investigations to date have focused on patients with known extra-cardiac sarcoidosis. The presence of CS is typically evaluated using 18F-fluorodeoxyglucose (18F-FDG) uptake on cardiac positron emission tomography (PET) or late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR). In this study, we sought to determine the prevalence of primary CS and the relationship between myocardial 18F-FDG uptake and LGE in patients with VT without known sarcoidosis. We retrospectively identified 67 patients without known sarcoidosis or active ischemic heart disease (i.e. significant ischemic disease that had not been previously revascularized) referred for both CMR and PET for evaluation of VT. Standard cine- and LGE- CMR and cardiac PET protocols were used. Myocardial LGE was defined as signal intensity > 5 SDs above the mean signal intensity of normal myocardium. Cardiac PET images were considered positive if there was focal myocardial 18F-FDG uptake having greater activity than the left ventricular blood pool. 45 patients (67%) had LGE, while only 4 (6%) had myocardial FDG uptake. Nine percent of patients with LGE had FDG-uptake while none without LGE did, and 10% of the cohort had indeterminate FDG uptake presumably from poor dietary preparation. Of those with both FDG uptake and LGE, 3/4 ultimately received a clinical diagnosis of CS. 4.5% of patients without previously known sarcoidosis or active ischemic heart disease presenting with VT have newly diagnosed CS. Detection of CS can be increased using a CMR first approach followed by cardiac PET for patients with non-ischemic LGE.

Update in Cardiac Sarcoidosis

Increasing awareness of cardiac manifestations of sarcoidosis and the widespread availability of advanced imaging tests have led to a tidal wave of interest in a condition that was once considered rare. In this Focused Review, we explore important clinical questions that may confront specialists faced with possible cardiac involvement. In the absence of an ideal reference standard, three main sets of clinical criteria exist: the Japanese Ministry of Health and Welfare, the Heart Rhythm Society, and the World Association for Sarcoidosis and Other Granulomatous Disorders criteria. Once cardiac sarcoidosis is suspected, clinicians should be familiar with the prevalence of the disease in different clinical scenarios. Before obtaining advanced cardiac imaging, electrocardiogram, ambulatory electrocardiogram, echocardiogram, and B-type natriuretic peptide may be useful. The available therapies for cardiac sarcoidosis include immunosuppression, antiarrhythmic medications, heart failure medications, device therapy, ablation therapy, and heart transplantation. Contemporary data suggest that long-term survival in cardiac sarcoidosis is better than previously believed. There is no randomized controlled trial demonstrating benefits of screening, but screening is recommended based on observational data.

The role of cardiac magnetic resonance in diagnosis of cardiac sarcoidosis

Sarcoidosis is a systemic granulomatous disease with a high prevalence of cardiac involvement in autopsic studies. Cardiac sarcoidosis is associated with increased cardiovascular morbidity and mortality. Endomyocardial biopsy is a specific technique, but unfortunately not sensitive enough. Non-invasive cardiac imaging has an important role in the evaluation of patients with suspected or confirmed cardiac sarcoidosis. Echocardiography remains the first choice imaging technique because of its availability and low cost. However, this method could not provide tissue characterization or evaluation of disease activity level. 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) has essential role in diagnosis and monitoring of patients with suspected or confirmed cardiac sarcoidosis. Nevertheless, more recently it has been shown that cardiac magnetic resonance (CMR) might provide useful information about cardiac sarcoidosis. Hybrid imaging approach that includes PET-CMR and PET-CT is particularly interesting for diagnosis, assessment of activity and follow-up in these patients. Diagnostic algorithm in sarcoidosis patients should include clinical data, hybrid imaging and biopsy. Use of different CMR sequences such as cine imaging, late gadolinium enhancement, T1 and T2 mapping, as well as strain imaging, may significantly contribute to diagnosis and monitoring of patients with cardiac sarcoidosis. However, validation of these techniques and particularly T1 and T2 mapping in sarcoidosis patients in large studies is necessary. This review aimed to summarize current knowledge about clinical usefulness of CMR in patients with cardiac sarcoidosis.

Role of CMR Mapping Techniques in Cardiac Hypertrophic Phenotype

Non-ischemic cardiomyopathies represent a heterogeneous group of myocardial diseases potentially leading to heart failure, life-threatening arrhythmias, and eventually death. Myocardial dysfunction is associated with different underlying pathological processes, ultimately inducing changes in morphological appearance. Thus, classification based on presenting morphological phenotypes has been proposed, i.e., dilated, hypertrophic, restrictive, and right ventricular cardiomyopathies. In light of the key diagnostic and prognostic role of morphological and functional features, cardiovascular imaging has emerged as key element in the clinical workflow of suspected cardiomyopathies, and above all, cardiovascular magnetic resonance (CMR) represents the ideal technique to be used: thanks to its physical principles, besides optimal spatial and temporal resolutions, incomparable contrast resolution allows to assess myocardial tissue abnormalities in detail. Traditionally, weighted images and late enhancement images after gadolinium-based contrast agent administration have been used to perform tissue characterization, but in the last decade quantitative assessment of pre-contrast longitudinal relaxation time (native T1), post-contrast longitudinal relaxation time (post-contrast T1) and transversal relaxation time (T2), all displayed with dedicated pixel-wise color-coded maps (mapping), has contributed to give precious knowledge insight, with positive influence of diagnostic accuracy and prognosis assessment, mostly in the setting of the hypertrophic phenotype. This review aims to describe the available evidence of the role of mapping techniques in the assessment of hypertrophic phenotype, and to suggest their integration in the routine CMR evaluation of newly diagnosed cardiomyopathies with increased wall thickness.

Applications of PET-MR Imaging in Cardiovascular Disorders

Cardiac PET/MR imaging is an integrated imaging approach that requires less radiation than PET/computed tomography and combines the high spatial resolution and morphologic data from MR imaging with the physiologic information from PET. This hybrid approach has the potential to improve the diagnostic and prognostic evaluation of several cardiovascular conditions, such as ischemic heart disease, infiltrative diseases such as sarcoidosis, acute and chronic myocarditis, and cardiac masses. Herein, the authors discuss the strengths of PET and MR imaging in several cardiovascular conditions; the challenges and potential; and the current data on the application of this powerful hybrid imaging modality.

T2 Relaxation Times at Cardiac MRI in Healthy Adults: A Systematic Review and Meta-Analysis

Background T2 mapping is an important cardiac MRI technique with applications in various conditions. However, a comprehensive evaluation of the T2 literature for normal values is lacking. Purpose To characterize the ranges of normal values and variability of myocardial T2 relaxation times using a systematic review and meta-analysis of the T2 literature. Materials and Methods PubMed and Cochrane Central were searched from June 2019 to January 2020 for myocardial T2 measurements in healthy adults. Studies quantifying T2 relaxation times conducted at 1.5 T or 3.0 T using gradient and spin-echo (GRASE) or T2-prepared balanced steady-state free precession sequences were included. Summary means were generated using a random-effects model. Subgroup analysis and meta-regression were performed to assess factors causing heterogeneity. Results Of the 2481 articles retrieved, 42 studies were included with 954 healthy adults (mean age, 42.4 years ± 10.5 [standard deviation]; 538 men). The pooled mean of T2 across studies was 52 msec at 1.5 T (95% confidence interval [CI]: 51 msec, 53 msec) and 46 msec at 3.0 T (95% CI: 44 msec, 48 msec) (P ≤ .001). I² was 98% at 1.5 T and 3.0 T. Meta-regression at 1.5 T and 3.0 T identified vendor (β at 1.5 T = -4 msec [with Philips as reference], P < .001; β at 3.0 T = -5 msec, P = .02) and pulse sequence (β at 1.5 T = -5 msec [with GRASE as reference], P < .001; β at 3.0 T = -6 msec, P = .002) as significant covariates, but it did not identify any association with covariates of age (β at 1.5 T = 0 msec per year, P = .70; β at 3.0 T = 0 msec per year, P = .83) or sex (β at 1.5 T = -1 msec, P = .88; β at 3.0 T = 6 msec, P = .42). Conclusion The pooled mean of T2 relaxation times in healthy adults had marked heterogeneity across studies with field strength, vendor, and pulse sequence identified as covariates associated with T2. T2-prepared measurements were similar between vendors at each field strength. © RSNA, 2020 Online supplemental material is available for this article.

Imaging of myocarditis and inflammatory cardiomyopathies

Myocarditis encompasses a wide range of myocardial inflammatory diseases, including acute myocarditis, chronic myocarditis and inflammatory cardiomyopathies, and myocardial inflammation associated with other cardiomyopathies. Because of this heterogeneity in clinical presentation, and the infrequent use of endomyocardial biopsy, cardiac imaging has gradually acquired a key role in the non-invasive detection of myocardial inflammation, the assessment of aetiology and the management of specific therapies. This article summarizes the issue of myocarditis and myocardial inflammation in clinical practice, and reviews the role of different non-invasive imaging techniques in the exploration of myocardial inflammation.

Complementary Value of Cardiac Magnetic Resonance Imaging and Positron Emission Tomography/Computed Tomography in the Assessment of Cardiac Sarcoidosis

BACKGROUND

Although cardiac magnetic resonance (CMR) and positron emission tomography (PET) detect different pathological attributes of cardiac sarcoidosis (CS), the complementary value of these tests has not been evaluated. Our objective was to determine the value of combining CMR and PET in assessing the likelihood of CS and guiding patient management.

METHODS AND RESULTS

In this retrospective study, we included 107 consecutive patients referred for evaluation of CS by both CMR and PET. Two experienced readers blinded to all clinical data reviewed CMR and PET images and categorized the likelihood of CS as no (<10%), possible (10%-50%), probable (50%-90%), or highly probable(>90%) based on predefined criteria. Patient management after imaging was assessed for all patients and across categories of increasing CS likelihood. A final clinical diagnosis for each patient was assigned based on a subsequent review of all available imaging, clinical, and pathological data. Among 107 patients (age, 55±11 years; left ventricular ejection fraction, 43±16%), 91 (85%) had late gadolinium enhancement, whereas 82 (76%) had abnormal F18-fluorodeoxyglucose uptake on PET, suggesting active inflammation. Among the 91 patients with positive late gadolinium enhancement, 60 (66%) had abnormal F18-fluorodeoxyglucose uptake. When PET data were added to CMR, 48 (45%) patients were reclassified as having a higher or lower likelihood of CS, most of them (80%) being correctly reclassified when compared with the final diagnosis. Changes in immunosuppressive therapies were significantly more likely among patients with highly probable CS.

CONCLUSIONS

Among patients with suspected CS, combining CMR and PET provides complementary value for estimating the likelihood of CS and guiding patient management.

Diagnostic Accuracy of Advanced Imaging in Cardiac Sarcoidosis

Background The diagnostic yield of cardiac sarcoidosis (CS) by endomyocardial biopsy is limited. Fluorodeoxyglucose (FDG) positron emission tomography (PET) and cardiac magnetic resonance imaging (MRI) may facilitate noninvasive diagnosis, but the accuracy of this approach is not well defined. We aimed to correlate findings from FDG PET and cardiac MRI with histological findings from explanted hearts of patients who underwent cardiac transplantation. Methods We analyzed the explanted heart histology for all patients who underwent cardiac transplant at our center from April 2008 to July 2018 and had pretransplant FDG PET (n=18) or cardiac MRI (n=31). The likelihood of CS based on FDG PET or cardiac MRI was categorized in a blinded fashion using a previously published method. RESULTS: Using a CS probable cutoff for FDG PET resulted in a sensitivity of 100.0% (95% CI, 54.1%-100.0%) and a specificity of 33.3% (95% CI, 9.9%-65.1%). Three of the 9 CS probable by FDG PET cases were found to be arrhythmogenic cardiomyopathy. The test characteristics of cardiac MRI are more challenging to comment on using our data as there was only one confirmed case of CS on post-transplant histological assessment. Of the 8 CS highly probable or probable cases by cardiac MRI, 3 were found to be dilated cardiomyopathy, and 2 were found to be end-stage hypertrophic cardiomyopathy. Conclusions FDG PET and cardiac MRI can help facilitate the diagnosis of CS in patients with advanced heart failure with a high degree of sensitivity but lower specificity.

Advanced Imaging in Cardiac Sarcoidosis

Sarcoidosis is a chronic disease of unknown etiology characterized by the presence of noncaseating granulomas. Cardiac involvement in sarcoidosis may lead to adverse outcomes such as advanced heart block, arrhythmias, cardiomyopathy, or death. Cardiac sarcoidosis can occur in patients with established sarcoidosis, or it can be the sole manifestation of the disease. Traditional diagnostic techniques, including echocardiography, have poor sensitivity for diagnosing cardiac sarcoidosis. The accumulating evidence supports the essential role of advanced cardiac imaging modalities such as MRI and PET in diagnosis, risk stratification, and management of patients with cardiac sarcoidosis. The current review highlights important theoretic and practical aspects of using cardiac imaging tools in the evaluation of patients with suspected or established cardiac sarcoidosis.

Quantitative cardiac MRI

Cardiac MRI has become an indispensable imaging modality in the investigation of patients with suspected heart disease. It has emerged as the gold standard test for cardiac function, volumes, and mass and allows noninvasive tissue characterization and the assessment of myocardial perfusion. Quantitative MRI already has a key role in the development and incorporation of machine learning in clinical imaging, potentially offering major improvements in both workflow efficiency and diagnostic accuracy. As the clinical applications of a wide range of quantitative cardiac MRI techniques are being explored and validated, we are expanding our capabilities for earlier detection, monitoring, and risk stratification of disease, potentially guiding personalized management decisions in various cardiac disease models. In this article we review established and emerging quantitative techniques, their clinical applications, highlight novel advances, and appraise their clinical diagnostic potential. Level of Evidence: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2020;51:693-711.

Advanced cardiovascular imaging for the evaluation of cardiac sarcoidosis

Cardiac sarcoidosis (CS) remains an intriguing infiltrating disorder and one of the most important forms of inflammatory cardiomyopathy. Identification of patients with CS is of extreme importance because they are at higher risk of sudden death, and heart-failure progression. And while it remains a diagnostic conundrum, a great amount of experience has been accumulated over the last decade with the advent of fluorine-18 fluorodeoxyglucose positron emission tomography and cardiac magnetic resonance with late gadolinium enhancement imaging. They have both proven to be advanced imaging techniques that provide important, and often complementary, diagnostic and prognostic information for the management of CS. However, they have also shown to have limitations, and, thus, there is a continued need for developing more specific imaging probes for identifying cardiac inflammation. The aim of the present manuscript is to provide the reader with a better understanding of the histopathology of the disease, how this potentially relates to noninvasive imaging detection, and the best strategies available for the diagnosis and management of patients with CS.

Cardiac Sarcoidosis

Clinical and subclinical cardiac sarcoidosis (CS) remains diagnostically challenging as the sensitivity and specificity of the diagnostic modalities are limited. The Japanese Ministry of Health and Welfare criteria and the Heart Rhythm Society expert consensus statement on CS are the most common guidelines used to diagnose CS. However, they are mostly based on expert opinions and lack clinical trial validation. The emergence and increase use of newer imaging modalities such as cardiac magnetic resonance and positron emission tomography may give valuable information for accurate diagnosis and assessment of treatment response in CS patient. Although immunosuppressive therapies, particularly corticosteroids, have been proposed as the mainstay of treatment in CS, there is paucity of data on the optimal initiation, duration, and dosage of immunosuppressive therapies. Recommendations are mostly based on small observational studies. Further studies are warranted to better characterize the use of immunosuppressive therapies in this patient population. Device therapies such as implantable cardioverter-defibrillators are usually recommended for patient with clinical CS. In conclusion, this article synthesizes the current best evidence of utilizing various imaging modalities to diagnose CS and summarizing the main therapeutic approaches to manage and treat CS.

Comprehensive evaluation of structural and functional myocardial impairments in Becker muscular dystrophy using quantitative cardiac magnetic resonance imaging

Aims

Becker muscular dystrophy (BMD) is a genetic neuromuscular disease characterized by an alteration of the dystrophin protein. Myocardial involvement is frequent, eventually progressing to a dilated cardiomyopathy, and represents the most common cause of death for this pathology. We performed a comprehensive evaluation of myocardial functional and structural alterations encountered in a large cohort of BMD patients using quantitative cardiac magnetic resonance (CMR) imaging.

Methods and results

Eighty-eight BMD patients and 26 age-matched volunteers underwent standard cine and tag imaging to assess myocardial function and dyssynchrony, while native T1, T2, and extracellular volume fraction (ECV) were measured for tissue characterization. The left ventricular ejection fraction (LV-EF) was significantly reduced in 26% of the BMD patients. Patients exhibited higher dyssynchrony index than controls (6.94 ± 3.17 vs. 5.09 ± 1.25, P = 0.005). Diastolic dyssynchrony also exists in patients where systolic function was normal. BMD subjects, compared with controls, had significantly higher native T1, T2, and ECV (1183 ± 60 ms vs. 1164 ± 22 ms, 47.5 ± 4.5 ms vs. 45.6 ± 3.4 ms, 0.282 ± 0.050 vs. 0.231 ± 0.027, respectively, P < 0.05). Native T1, T2, and ECV correlated with LV-EF (R = −0.79, −0.70, and −0.71, respectively, P < 0.001) and N-terminal-pro brain natriuretic peptide (R = 0.51, 0.58, and 0.44, respectively, P < 0.001).

Conclusion

Quantitative CMR represents a powerful tool to evaluate structural and functional impairments in the myocardium of BMD subjects. Native T1, T2, and ECV provided quantitative biomarkers related to inflammation and fibrosis, and could stratify disease severity.

Cardiac Magnetic Resonance Imaging for Diagnosis of Cardiac Sarcoidosis: A Meta-Analysis

Background

Cardiac magnetic resonance imaging (CMR) is an effective technique for the diagnosis of cardiac sarcoidosis (CS). The efficacy of CMR versus the Japanese Ministry of Health and Welfare (JMHW) guidelines considered as standard criterion for the diagnosis of CS remains to be elucidated.

Methods

In this systematic review and meta-analysis, we aimed at assessing the diagnostic accuracy of CMR in cardiac sarcoidosis. We searched on PubMed from January 1, 1980, to March 28, 2018, on Embase from January 1, 1980, to March 29, 2018, and on the Cochrane Library from January 1, 1980, to April 1, 2018, using a strategy based on the search terms (sarcoidosis and magnetic resonance imaging) independently. We analyzed the data obtained with Revman 5.3 and Stata 14.0 software.

Results

Eight studies with a total of 649 participants met the inclusion criteria, and data were extracted. CMR had an overall sensitivity of 0.93 (95% confidence interval (CI), 0.87–0.97) and specificity of 0.85 (95% CI, 0.68–0.94) for the diagnosis of cardiac sarcoidosis. The area under the summary receiver operating characteristic (SROC) curve was 0.95 (95% CI, 0.93–0.97). The subgroup analysis via public year showed that studies between 2011 and 2017 had an overall sensitivity of 0.95 (95% CI, 0.88–0.98) and specificity of 0.92 (95% CI, 0.49–0.99), with an area under the SROC curve being 0.96.

Conclusions

The results of this meta-analysis suggest that CMR could be used for the diagnosis of cardiac sarcoidosis and screening of patients suspected of CS. With the improvement of the technique, the diagnostic accuracy of MRI has improved.

Cardiac Magnetic Resonance Fingerprinting: Technical Overview and Initial Results

Cardiovascular magnetic resonance is a versatile tool that enables noninvasive characterization of cardiac tissue structure and function. Parametric mapping techniques have allowed unparalleled differentiation of pathophysiological differences in the myocardium such as the delineation of myocardial fibrosis, hemorrhage, and edema. These methods are increasingly used as part of a tool kit to characterize disease states such as cardiomyopathies and coronary artery disease more accurately. Currently conventional mapping techniques require separate acquisitions for T1 and T2 mapping, the values of which may depend on specifics of the magnetic resonance imaging system hardware, pulse sequence implementation, and physiological variables including blood pressure and heart rate. The cardiac magnetic resonance fingerprinting (cMRF) technique has recently been introduced for simultaneous and reproducible measurement of T1 and T2 maps in a single scan. The potential for this technique to provide consistent tissue property values independent of variables including scanner, pulse sequence, and physiology could allow an unbiased framework for the assessment of intrinsic properties of cardiac tissue including structure, perfusion, and parameters such as extracellular volume without the administration of exogenous contrast agents. This review seeks to introduce the basics of the cMRF technique, including pulse sequence design, dictionary generation, and pattern matching. The potential applications of cMRF in assessing diseases such as nonischemic cardiomyopathy are also briefly discussed, and ongoing areas of research are described.

Management and outcomes of cardiac sarcoidosis: a 20-year experience in two tertiary care centres

AIMS

Cardiac sarcoidosis (CS) often presents with ventricular arrhythmias, heart block, and cardiomyopathy. The prognosis of CS with contemporary management is uncertain. We estimated the impact of baseline and treatment variables on left ventricular ejection fraction (LVEF), ventricular assist device placement, heart transplant, and death.

METHODS AND RESULTS

We identified patients with CS seen from 1994-2014 at two large academic medical centres. All met the 2014 Heart Rhythm Society expert consensus criteria for diagnosis. From the 574 patients identified, 91 met inclusion criteria. Twenty-two (24.2%) were diagnosed by endomyocardial biopsy. Cardiomyopathy was the primary presentation in 47 patients (51.6%). Within 90 days of diagnosis, 41 patients (45.0%) received prednisone alone, 29 (31.9%) received alternative immunosuppression with or without prednisone, and 21 (23.1%) received no immunosuppression. During follow-up, 31 of 47 cardiomyopathy patients experienced improvement in LVEF, while 23 experienced decline in LVEF or clinical exacerbation, and 15 of 22 patients presenting with ventricular arrhythmia had recurrence. These results did not differ by treatment group. During a median follow-up of 44 months for our cohort, 14 patients reached the composite endpoint of ventricular assist device placement, heart transplant, or death. Survival without the composite outcome did not differ by treatment group, but was worse among patients presenting with cardiomyopathy (log-rank = 0.005).

CONCLUSION

In a large series of CS subjects, rates of ventricular arrhythmia and heart failure events remain high with no treatment regimen clearly associated with better outcome. Patients with cardiomyopathy at diagnosis were more likely to reach the composite endpoint.

Role of Cardiac Magnetic Resonance in the Diagnosis and Prognosis of Nonischemic Cardiomyopathy

Cardiac magnetic resonance (CMR) is a valuable tool for the evaluation of patients with, or at risk for, heart failure and has a growing impact on diagnosis, clinical management, and decision making. Through its ability to characterize the myocardium by using multiple different imaging parameters, it provides insight into the etiology of the underlying heart failure and its prognosis. CMR is widely accepted as the reference standard for quantifying chamber size and ejection fraction. Additionally, tissue characterization techniques such as late gadolinium enhancement (LGE) and other quantitative parameters such as T₁ mapping, both native and with measurement of extracellular volume fraction; T₂ mapping; and T₂* mapping have been validated against histological findings in a wide range of clinical scenarios. In particular, the pattern of LGE in the myocardium can help determine the underlying etiology of the heart failure. The presence and extent of LGE determine prognosis in many of the nonischemic cardiomyopathies. The use of CMR should increase as its utility in characterization and assessment of prognosis in cardiomyopathies is increasingly recognized.

T2 mapping and T2* imaging in heart failure

Cardiovascular magnetic resonance (CMR) is a versatile imaging modality that enables aetiological assessment and provides additional information to that of standard echocardiography in a significant proportion of patients with heart failure. In addition to highly accurate and reproducible assessment of ventricular volumes and replacement fibrosis, multiparametric mapping techniques have rapidly evolved to further expand the diagnostic and prognostic applications in various conditions ranging from acute inflammatory and ischaemic cardiomyopathy, to cardiac involvement in systemic diseases such as sarcoidosis and iron overload cardiomyopathy. In this review, we discuss the established role of T2* imaging and rapidly evolving clinical applications of myocardial T2 mapping as quantitative adjuncts to established qualitative imaging techniques.

Cardiovascular magnetic resonance imaging and clinical performance of somatostatin receptor positron emission tomography in cardiac sarcoidosis

AIMS

Cardiac affection constitutes a major limiting condition in systemic sarcoidosis. The primary objective of this study was to investigate the persistence rate of cardiac sarcoid involvement by cardiovascular magnetic resonance (CMR) imaging in patients diagnosed with cardiac sarcoidosis (CS). Moreover, we examined the additional insights into myocardial damage's characteristics gained by somatostatin receptor scintigraphy.

METHODS AND RESULTS

In a pilot study, we had previously identified cardiac involvement-diagnosed by CMR imaging-to be present in 29 of 188 patients (15.4%) with histologically proven, extra-CS. Out of these initial 29 CS-positive patients, 27 patients (49.9 ± 11.8 years, 59.3% male) were presently re-examined and underwent a second CMR study and complementary standard clinical testing. Somatostatin receptor scintigraphy using the ligand 68 Ga-DOTATOC was additionally performed when clinically indicated (17 patients). Within a median follow-up period of 2.6 years, none of the initial 29 patients deceased or experienced aborted sudden cardiac death. However, two patients developed third-degree atrioventricular block that required device therapy. Among the 27 re-examined CS patients, pathological CMR findings persisted in 14 of 27 patients (51.9%). CS remission was primarily due to a resolution of acute inflammatory processes. 68 Ga-DOTATOC positron emission tomography/computed tomography (PET/CT) identified one patient with regions of raised tracer uptake that concorded with acute inflammatory changes, as assessed by CMR; this patient received no immunosuppressive medication at the time of PET/CT execution.

CONCLUSIONS

Within follow-up, CS persisted in barely half the patients, and the patients were not afflicted with cardiac death. Additional 68 Ga-DOTATOC PET/CT allowed for visualization of acute myocardial inflammation.

Right ventricular involvement in cardiac sarcoidosis demonstrated with cardiac magnetic resonance

AIMS

Cardiac involvement in sarcoidosis is reported in up to 30% of patients. Left ventricular involvement demonstrated by contrast-enhanced cardiac magnetic resonance has been well validated. We sought to determine the prevalence and distribution of right ventricular late gadolinium enhancement in patients diagnosed with pulmonary sarcoidosis.

METHODS AND RESULTS

We prospectively evaluated 87 patients diagnosed with pulmonary sarcoidosis with contrast-enhanced cardiac magnetic resonance for right ventricular involvement. Pulmonary artery pressures were non-invasively evaluated with Doppler echocardiography. Patient characteristics were compared between the groups with and without right ventricular involvement, and right ventricular enhancement was correlated with pulmonary hypertension, ventricular mass, volume, and systolic function. Left ventricular late gadolinium enhancement was demonstrated in 30 patients (34%). Fourteen patients (16%) had right ventricular late gadolinium enhancement, with sole right ventricular enhancement in only two patients. The pattern of right ventricular enhancement consisted of right ventricular outflow tract enhancement in 1 patient, free wall enhancement in 8 patients, ventricular insertion point enhancement in 10 patients, and enhancement of the right side of the interventricular septum in 11 patients. Pulmonary arterial hypertension correlated with the presence of right ventricular enhancement (P < 0.001). Right ventricular enhancement correlated with systolic ventricular dysfunction (P < 0.001), hypertrophy (P = 0.001), and dilation (P < 0.001).

CONCLUSIONS

Right ventricular enhancement was present in 16% of patients diagnosed with pulmonary sarcoidosis and in 48% of patients with left ventricular enhancement. The presence of right ventricular enhancement correlated with pulmonary arterial hypertension, right ventricular systolic dysfunction, hypertrophy, and dilation.

Clinical recommendations for cardiovascular magnetic resonance mapping of T1, T2, T2* and extracellular volume: A consensus statement by the Society for Cardiovascular Magnetic Resonance (SCMR) endorsed by the European Association for Cardiovascular Imaging (EACVI)

Parametric mapping techniques provide a non-invasive tool for quantifying tissue alterations in myocardial disease in those eligible for cardiovascular magnetic resonance (CMR). Parametric mapping with CMR now permits the routine spatial visualization and quantification of changes in myocardial composition based on changes in T1, T2, and T2*(star) relaxation times and extracellular volume (ECV). These changes include specific disease pathways related to mainly intracellular disturbances of the cardiomyocyte (e.g., iron overload, or glycosphingolipid accumulation in Anderson-Fabry disease); extracellular disturbances in the myocardial interstitium (e.g., myocardial fibrosis or cardiac amyloidosis from accumulation of collagen or amyloid proteins, respectively); or both (myocardial edema with increased intracellular and/or extracellular water). Parametric mapping promises improvements in patient care through advances in quantitative diagnostics, inter- and intra-patient comparability, and relatedly improvements in treatment. There is a multitude of technical approaches and potential applications. This document provides a summary of the existing evidence for the clinical value of parametric mapping in the heart as of mid 2017, and gives recommendations for practical use in different clinical scenarios for scientists, clinicians, and CMR manufacturers.

Right ventricular involvement and the extent of left ventricular enhancement with magnetic resonance predict adverse outcome in pulmonary sarcoidosis

AIMS

Cardiac involvement is the main determinant of poor outcomes in sarcoidosis. Right ventricular (RV) dysfunction and left ventricular (LV) late gadolinium enhancement (LGE) have been reported to be predictive of adverse outcome in non-ischaemic cardiomyopathies. The aim of our study was to determine whether delayed RV LGE with cardiovascular magnetic resonance would be predictive of adverse events in addition to LV LGE during the long-term follow-up of pulmonary sarcoidosis patients.

METHODS AND RESULTS

Eighty-four consecutive biopsy-proven pulmonary sarcoidosis patients were followed for a median of 56 months [38-74] after baseline delayed contrast-enhanced cardiac magnetic resonance. The composite primary endpoint consisted of admission for congestive heart failure, sustained ventricular tachycardia, appropriate implantable cardioverter defibrillator therapy, pacemaker implantation for high degree atrio-ventricular block, or cardiac death. The composite secondary endpoint included all-cause mortality in addition to the primary endpoint. RV and LV LGE were demonstrated in respectively 12 and 27 patients. Five of 10 events included in the primary endpoint occurred in the group with RV LGE. RV LGE, LV, or biventricular LGE yielded Cox hazard ratios of 8.71 [95% confidence interval (CI) 1.90-23.81], 9.22 (95% CI 1.96-43.45), and 12.09 (95% CI 3.43-42.68) for the composite primary endpoint. In a multivariate model, the predictive value of biventricular LGE for the composite primary and secondary endpoints was strongest. Kaplan-Meier event-free survival curves were most significant for RV LGE and biventricular LGE (log rank with P < 0.001).

CONCLUSIONS

Biventricular LGE at presentation is the strongest, independent predictor of adverse outcome during long-term follow-up. Asymptomatic myocardial scar <8% of LV mass carried a favourable long-term outcome.