Cardiac sarcoidosis: a pathology-focused review

The active papillary muscle sign in 18F-FDG PET/CT cardiac sarcoidosis exams and its relationship with myocardial suppression

OBJECTIVE

Papillary muscle (PM) activity may demonstrate true active cardiac sarcoidosis (CS) or mimic CS in 18FDG-PET/CT if adequate myocardial suppression (MS) is not achieved. We aim to examine whether PM uptake can be used as a marker of failed MS and measure the rate of PM activity presence in active CS with different dietary preparations.

MATERIALS AND METHODS

We retrospectively reviewed PET/CTs obtained with three different dietary preparations. Diet-A: 24-h ketogenic diet with overnight fasting (n = 94); Diet-B: 18-h fasting (n = 44); and Diet-C: 72-h daytime ketogenic diet with 3-day overnight fasting (n = 98). Each case was evaluated regarding CS diagnosis (negative, positive, and indeterminant) and presence of PM activity. MaxSUV was measured from bloodpool, liver, and the most suppressed normal myocardium. Linear mixed-effects models were used to compare these factors between those with PM activity and those without.

RESULTS

PM activity was markedly lower in the Diet-C group compared with others: Diet-C: 6 (6.1%), Diet-A: 36 (38.3%), and Diet-B: 26 (59.1%) (p < 0.001). MyocardiumMaxSUV was higher, and MyocardiummaxSUV/BloodpoolmaxSUV, MyocardiummaxSUV/LivermaxSUV ratios were significantly higher in the cases with PM activity (p < 0.001). Among cases that used Diet-C and had PM activity, 66.7% were positive and 16.7% were indeterminate. If Diet-A or Diet-B was used, those with PM activity had a higher proportion of indeterminate cases (Diet-A: 61.1%, Diet-B: 61.5%) than positive cases (Diet-A: 36.1%, Diet-B: 38.5%).

CONCLUSION

Lack of PM activity can be a sign of appropriate MS. PM activity is less common with a specific dietary preparation (72-h daytime ketogenic diet with 3-day overnight fasting), and if it is present with this particular preparation, the likelihood that the case being true active CS might be higher than the other traditional dietary preparations.

The inflammatory spectrum of cardiomyopathies

Infiltration of the myocardium with various cell types, cytokines and chemokines plays a crucial role in the pathogenesis of cardiomyopathies including inflammatory cardiomyopathies and myocarditis. A more comprehensive understanding of the precise immune mechanisms involved in acute and chronic myocarditis is essential to develop novel therapeutic approaches. This review offers a comprehensive overview of the current knowledge of the immune landscape in cardiomyopathies based on etiology. It identifies gaps in our knowledge about cardiac inflammation and emphasizes the need for new translational approaches to improve our understanding thus enabling development of novel early detection methods and more effective treatments.

A novel combination of filamin C mutation and cardiorespiratory sarcoidosis in a patient with left ventricular systolic dysfunction

Cardiac sarcoidosis is an unpredictable, rare and potentially lethal condition whereby patients are exposed to sudden cardiac death. However, despite sophisticated imaging techniques and the need for careful multidisciplinary team assessment and management, the contribution from genetic mutations is uncertain. Hence, the case describes a novel observation of a patient who possessed both a filamin C mutation and cardiac sarcoidosis. The case highlights the need for detailed dedicated investigation and highlights the need for the consideration of genetic screening within patients with cardiac sarcoidosis.

Impact of comorbid heart failure among hospitalized patients with sarcoidosis: A United States population-based cohort study

Background

There is paucity of data regarding the impact of concomitant heart failure (HF) on the in-hospital outcomes among hospitalized sarcoidosis patients. We aim to investigate the factors associated with concomitant HF and its impact on in-hospital outcomes among hospitalized sarcoidosis patients.

Methods

We utilized the 2018-2020 National Inpatient Sample (NIS) Database in conducting this study. Multivariable logistic and linear regression models were used to examine the factors associated with HF and hospital-associated outcomes among patients with sarcoidosis.

Results

A total of 36,864 hospitalized patients with sarcoidosis were identified, of which 24.78 % (n = 9135/36,864) had concomitant HF. Factors associated with concomitant HF were age (aOR 1.03; 95 % CI: 1.02-1.03, p value ≤ 0.001), black race (aOR 1.74; 95 % CI: 1.47-2.05, p value ≤ 0.001), not being female (aOR 0.79; 95 % CI: 0.69-0.91, p value ≤ 0.001), and arrhythmias (aOR 2.50; 95 % CI: 2.10-2.98, p value ≤ 0.001) specifically atrial fibrillation and ventricular tachycardia. Comorbidities associated with concomitant HF in this population were hyperlipidemia, obesity, coronary artery disease, cardiac device implantation history, and chronic kidney disease stage 1-4. Concomitant HF was not an independent predictor of in-hospital mortality or length of stay (LOS). However, age (aOR 1.04; 95 % CI, 1.03-1.06; p ≤ 0.001) and arrhythmia burden (aOR 2.08; 95 % CI, 1.47-2.95; p ≤ 0.001), specifically ventricular tachycardia and fibrillation, were independently associated with in-hospital mortality among sarcoidosis patients.

Conclusion

Traditional cardiovascular risk factors were associated with concomitant HF among hospitalized sarcoidosis patients. Moreover, concomitant HF among sarcoidosis patients was not significantly associated with in-hospital mortality or LOS.

High-risk and low prevalence disease: Cardiac sarcoidosis and some of its mimics

In this narrative review of cardiac sarcoidosis, based on a literature search using the terms "cardiac sarcoidosis", "tuberculous myocarditis", "Whipple's disease and myocarditis", and"idiopathic giant cell myocarditis", I have defined cardiac sarcoidosis as a disorder which can be diagnosed either by documentation of the presence of sarcoid-related granulomas in myocardial tissue or by documentation of the association of the presence of sarcoid-related granulomas in extracardiac tissue and symptoms such as complete heart block, ventricular tachyarrhythmia, sudden death or dilated cardiomyopathy which are typical of cardiac sarcoidosis. The differential diagnosis of cardiac sarcoidosis includes granulomatous myocarditis attributable to underlying causes such as such as tuberculosis, Whipple's disease, and idiopathic giant cell myocarditis. Diagnostic pathways for cardiac sarcoidosis include biopsy of cardiac and extracardiac tissue, nuclear magnetic resonance imaging, positron emission tomography, and a diagnostic trial of empiric therapy. Problem areas include differentiation between noncaseating granulomatosis attributable to sarcoidosis versus noncaseating granulomatosis attributable to tuberculosis and whether or not the workup of suspected cardiac sarcoidosis should always include evaluation of biopsy tissue by molecular methods for M tuberculosis DNA as well as by mycobacterium tuberculosis culture. The diagnostic significance of necrotising granulomatosis is also unclear. Evaluation of patients on long term immunotherapy should also take due account of the risk of tuberculosis attributable to the use of tumor necrosis factor-alpha antagonists.

Cardiac Sarcoidosis: A Literature Review of Current Recommendations on Diagnosis and Management

Cardiac sarcoidosis (CS) is a rare multisystem disorder characterized by granulomatous infiltration of the myocardium, which can lead to significant morbidity and mortality. Its clinical manifestations range from asymptomatic conduction abnormalities to severe heart failure (HF) and sudden cardiac death. This comprehensive review aims to provide an overview of the diagnosis, clinical features, and current medical management strategies for CS. Additionally, the role of implantable cardioverter-defibrillators (ICDs) and the potential use of positron emission tomography in guiding management decisions are explored. A comprehensive understanding of the medical management of CS is essential for improving patient outcomes and guiding future research endeavors.

Cardiac sarcoidosis: a comprehensive review of risk factors, pathogenesis, diagnosis, clinical manifestations, and treatment strategies

Cardiac Sarcoidosis (CS) is a deadly consequence of systemic sarcoidosis that inflames all three layers of the heart, especially the myocardium-clinical signs of CS range from asymptomatic disease to abrupt cardiac death. CS generally remains undiagnosed secondary to a lack of definitive diagnostic criteria, a high percentage of false negative results on endomyocardial biopsy, and ill-defining clinical manifestations of the disease. Consequently, there is a lack of evidence-based recommendations for CS, and the present diagnostic and therapeutic management depend on expert opinion. The aetiology, risk factors, clinical symptoms, diagnosis, and therapy of CS will be covered in this review. A particular emphasis will be placed on enhanced cardiovascular imaging and early identification of CS. We review the emerging evidence regarding the use of Electrocardiograms (ECGs), Magnetic Resonance Imaging (MRI), and Positron Emission Tomography (PET) imaging of the heart to identify and quantify the extent of myocardial inflammation, as well as to guide the use of immunotherapy and other treatment regimens, such as ablation therapy, device therapy, and heart transplantation, to improve patient outcomes.

Cardiac sarcoidosis: is early diagnosis possible? Case report

Cardiac involvement in sarcoidosis is difficult to diagnose due to the asymptomatic course in 95% of cases, the inaccessibility and low information content of a heart biopsy, the absence of pathological disorders in routine examination methods or their non-specificity. At the same time, it is cardiac sarcoidosis, along with damage to the nervous system, that is the main cause of mortality in sarcoidosis. Early diagnosis is of decisive importance for preventing complications associated with heart involvement and choosing the right treatment tactics. The positron emission tomography-computed tomography (PET-CT) is a method that can help the doctor in assessing the prevalence of sarcoidosis and verifying latent localizations in patients with a morphologically confirmed disease. The article describes a case of the use of PET/CT for the diagnosis of cardiac sarcoidosis.

Sarcoid Heart Disease: Review of Current Knowledge

Sarcoidosis is a granulomatous disease with the potential of multiple organ system involvement and its etiology remains unknown. Cardiac involvement is associated with worse clinical outcome, and has been reported to be 20-30% in white and as high as 58% in Japanese populations with sarcoidosis. Clinical manifestations of cardiac sarcoidosis highly depend on the extent and location of granulomatous inflammation. The most frequent presentations include heart block, tachyarrhythmia, or heart failure. Endomyocardial biopsy is the most specific diagnostic test, but has poor sensitivity due to often patchy involvement. The diagnosis of cardiac sarcoidosis remains challenging due to nonspecific imaging findings. Both 18 F-fluorodeoxyglucose-positron emission tomography (FDG-PET) and cardiac magnetic resonance imaging can be used to evaluate cardiac sarcoidosis, but evaluate different stages of the disease process. FDG-PET detects metabolically active inflammatory cells while cardiac magnetic resonance imaging with late gadolinium enhancement reveals areas of myocardial necrosis and fibrosis. Aggressive therapy of symptomatic cardiac sarcoidosis is often sought due to the high risk of sudden death and/or progression to heart failure. Prednisone 20-40 mg a day is the recommended initial treatment. In refractory or severe cases, higher doses of prednisone, 1-1.5 mg/kg/d (or its equivalent) and addition of a steroid-sparing agent have been utilized. Methotrexate is added most commonly. Long-term improvement has been reported with the use of a combination of weekly methotrexate and prednisone versus prednisone alone. After initiation of treatment, a cardiac FDG-PET scan may be performed 2-3 months later to assess treatment response.

Outcomes after transvenous defibrillator implantation in cardiac sarcoidosis: A systematic review

Introduction

Sarcoidosis is a systemic inflammatory disorder associated with ventricular arrhythmias (VAs) and sudden death in the context of cardiac involvement. Guidelines advocate implantable cardioverter‐defibrillator (ICD) implantation in specific subcohorts, but there is a paucity of data on outcomes.

Methods and Results

A systematic review was performed to assess outcomes in patients with definite or probable cardiac sarcoidosis (CS) treated with ICD. Observational studies were identified from multiple databases from inception to 21st May 2021. Outcomes of interest included appropriate and inappropriate ICD therapies in addition to all‐cause mortality. Study quality was assessed individually using the Newcastle Ottawa Scale (NOS).

Eight studies were identified comprising 530 patients, with follow‐up period of 24–66 months (weighted average 40 months). Mean age was 53.9 years with ejection fraction of 41.3%. Overall incidence of appropriate therapy was 38.1% during follow‐up. Left ventricular systolic dysfunction (LVSD) with ejection fraction <40% was a predictor of appropriate therapy in the majority of studies, as were sustained VAs during electrophysiological testing (EP) in one study. There was no interaction with device indication (i.e. primary or secondary). Where documented, inappropriate therapy was primarily driven by atrial arrhythmias. All‐cause mortality was 6.0% over a median follow‐up period of 42 months. Only three studies achieved good quality in the comparability domain of NOS.

Conclusions

Appropriate ICD therapy in patients with CS is commonly associated with LVSD, which can act as a surrogate for scar burden. The utility of EP testing in this setting remains unclear.

Performance of cardiac PET/CT with and without phase analysis for detection of scar in cardiac sarcoidosis: Comparison to cardiac magnetic resonance imaging

BACKGROUND

The presence of myocardial scar in CS patients results in poor prognosis and worse outcomes. 18F-fluorodeoxyglucose (18F-FDG) PET/CT excels at visualizing inflammation but is suboptimal at detecting scar. We evaluated PET/CT sensitivity to detect scar and investigated the incremental diagnostic value of automated PET-derived data.

METHODS

176 patients who underwent cardiac magnetic resonance (CMR) and N-13 ammonia/18F-FDG cardiac PET/CT for suspected CS within 3 months were enrolled. Scar was defined as late gadolinium enhancement (LGE) on CMR without concordant 18F-FDG uptake on 18F-FDG PET/CT. Accuracy of cardiac PET/CT at detecting scar (perfusion defect without concordant 18F-FDG uptake) was assessed before and after addition of automated PET-derived data.

RESULTS

Sensitivity of PET/CT for scar detection was 45.3% (specificity 88.9%). Addition of PET-derived LV volumes and function in a logistic regression model improved sensitivity to 57.0% (specificity: 80.0%, AUC 0.72). Addition of phase analysis maximum segmental onset of myocardial contraction > 61 improved AUC to 0.75, correctly relabeling 16.3% of patients as scar (net reclassification index 8.2%).

CONCLUSION

Sensitivity of gated PET MPI alone for scar detection in CS is suboptimal. Adding PET-derived volumes/function and phase analysis data results in improved detection and characterization of scar.

Histology of Cardiac Sarcoidosis with Novel Considerations Arranged upon a Pathologic Basis

Sarcoidosis is a rare disease of isolated or diffuse granulomatous inflammation. Although any organs can be affected by sarcoidosis, cardiac sarcoidosis is a fatal disorder, and it is crucial to accurately diagnose it to prevent sudden death due to dysrhythmia. Although endomyocardial biopsy is invasive and has limited sensitivity for identifying granulomas, it is the only modality that yields a definitive diagnosis of cardiac sarcoidosis. It is imperative to develop novel pathological approaches for the precise diagnosis of cardiac sarcoidosis. Here, we aimed to discuss commonly used diagnostic criteria for cardiac sarcoidosis and to summarize useful and novel histopathologic criteria of cardiac sarcoidosis. While classical histologic observations including noncaseating granulomas and multinucleated giant cells (typically Langhans type) are the most important findings, others such as microgranulomas, CD68⁺ CD163^- pro-inflammatory (M1) macrophage accumulation, CD4/CD8 T-cell ratio, Cutibacterium acnes components, lymphangiogenesis, confluent fibrosis, and fatty infiltration may help to improve the sensitivity of endomyocardial biopsy for detecting cardiac sarcoidosis. These novel histologic findings are based on the pathology of cardiac sarcoidosis. We also discussed the principal histologic differential diagnoses of cardiac sarcoidosis, such as tuberculosis myocarditis, fungal myocarditis, giant cell myocarditis, and dilated cardiomyopathy.

PET Imaging in Cardiac Sarcoidosis: A Narrative Review with Focus on Novel PET Tracers

Sarcoidosis is a multi-system inflammatory disease characterized by the development of inflammation and noncaseating granulomas that can involve nearly every organ system, with a predilection for the pulmonary system. Cardiac involvement of sarcoidosis (CS) occurs in up to 70% of cases, and accounts for a significant share of sarcoid-related mortality. The clinical presentation of CS can range from absence of symptoms to conduction abnormalities, heart failure, arrhythmias, valvular disease, and sudden cardiac death. Given the significant morbidity and mortality associated with CS, timely diagnosis is important. Traditional imaging modalities and histologic evaluation by endomyocardial biopsy often provide a low diagnostic yield. Cardiac positron emission tomography (PET) has emerged as a leading advanced imaging modality for the diagnosis and management of CS. This review article will summarize several aspects of the current use of PET in CS, including indications for use, patient preparation, image acquisition and interpretation, diagnostic and prognostic performance, and evaluation of treatment response. Additionally, this review will discuss novel PET radiotracers currently under study or of potential interest in CS.

Cardiac Sarcoidosis: A Clinical Overview

Cardiac sarcoidosis (CS) with clinical manifestation occurs in about 5-8% of patients with sarcoidosis. CS may be clinically suspected by the presence of ventricular arrhythmia, conduction abnormalities, and heart failure (HF). However, 20%-25% of patients may present with silent CS, having asymptomatic cardiac involvement. The diagnosis of CS is based on findings from nuclear studies, cardiac magnetic resonance, and extra-cardiac tissue biopsy. Due to the inflammatory nature of the disease, immunosuppressive medications are a cornerstone of therapy. The treatment also includes recommended HF medical therapies. Since CS patients are at risk of sudden cardiac death resulting from progression of cardiac dysfunction or the presence of scar originating from fatal arrhythmias, implantable cardioverter-defibrillators should be considered, with special indication beyond accepted recommendations in HF. In CS, the extent of left ventricular dysfunction is the most important mortality predictor. Heart transplant or mechanical circulatory support may represent life saving strategies in selective CS patients.

Cardiac Sarcoidosis: Pathophysiology, Diagnosis, and Management

Sarcoidosis is a chronic multi-system disorder with an unknown etiology that can affect the cardiac tissue, resulting in Cardiac Sarcoidosis (CS). The majority of these CS cases are clinically silent, and when there are symptoms, the symptoms are vague and can have a lot in common with other common cardiac diseases. These symptoms can range from arrhythmias to heart failure. If CS goes undetected, it can lead to detrimental outcomes for patients. Diagnosis depends on timely utilization of imaging modalities and non-invasive testing, while in some cases, it does necessitate biopsy. Early diagnosis and treatment with immunosuppressive agents are crucial, and it is essential that follow-up testing be performed to ensure resolution and remission. This manuscript provides an in-depth review of CS and the current literature regarding CS diagnosis and treatment.

Arrhythmia in Cardiac Sarcoidosis

Cardiac sarcoidosis (CS) is a complex disease that can manifest as a diverse array of arrhythmias. CS patients may be at higher risk for sudden cardiac death (SCD), and, in some cases, SCD may be the first presenting symptom of the underlying disease. As such, identification, risk stratification, and management of CS-related arrhythmia are crucial in the care of these patients. Left untreated, CS carries significant arrhythmogenic morbidity and mortality. Cardiac manifestations of CS are a consequence of an inflammatory process resulting in the myocardial deposition of noncaseating granulomas. Endomyocardial biopsy remains the gold standard for diagnosis; however, biopsy yield is limited by the patchy distribution of the granulomas. As such, recent guidelines have improved clinical diagnostic pathways relying on advanced cardiac imaging to help in the diagnosis of CS. To date, corticosteroids are the best studied agent to treat CS but are associated with significant risks and limited benefits. Implantable cardioverter-defibrillators have an important role in SCD risk reduction. Catheter ablation in conjunction with antiarrhythmics seems to reduce ventricular arrhythmia burden. However, the appropriate selection of these patients is crucial as ablation is likely more helpful in the setting of a myocardial scar substrate versus arrhythmia driven by active inflammation. Further studies investigating CS pathophysiology, the pathway to diagnosis, arrhythmogenic manifestations, and SCD risk stratification will be crucial to reduce the high morbidity and mortality of this disease.

Myocardial Accumulations of Reg3A, Reg3γ and Oncostatin M Are Associated with the Formation of Granulomata in Patients with Cardiac Sarcoidosis

Cardiac sarcoidosis (CS) is a poorly understood disease and is characterized by the focal accumulation of immune cells, thus leading to the formation of granulomata (GL). To identify the developmental principles of fatal GL, fluorescence microscopy and Western blot analysis of CS and control patients is presented here. CS is visualized macroscopically by positron emission tomography (PET)/ computed tomography (CT). A battery of antibodies is used to determine structural, cell cycle and inflammatory markers. GL consist of CD68⁺, CD163⁺ and CD206⁺ macrophages surrounded by T-cells within fibrotic areas. Cell cycle markers such as phospho-histone H3, phospho-Aurora and Ki67 were moderately present; however, the phosphorylated ERM (ezrin, radixin and moesin) and Erk1/2 proteins, strong expression of the myosin motor protein and the macrophage transcription factor PU.1 indicate highly active GL. Mild apoptosis is consistent with PI3 kinase and Akt activation. Massive amounts of the IL-1R antagonist reflect a mild activation of stress and inflammatory pathways in GL. High levels of oncostatin M and the Reg3A and Reg3γ chemokines are in accordance with macrophage accumulation in areas of remodeling cardiomyocytes. We conclude that the formation of GL occurs mainly through chemoattraction and less by proliferation of macrophages. Furthermore, activation of the oncostatin/Reg3 axis might help at first to wall-off substances but might initiate the chronic development of heart failure.

Advanced Nuclear Medicine and Molecular Imaging in the Diagnosis of Cardiomyopathy

OBJECTIVE. The purpose of this article is to summarize the protocol, interpretation, and diagnostic performance of nuclear medicine and molecular imaging in imaging two distinctive, underdiagnosed cardiomyopathies: cardiac amyloidosis and cardiac sarcoidosis. CONCLUSION. Emerging new radiotracers and advanced molecular imaging modalities enable us to noninvasively characterize certain types of cardiomyopathies, including cardiac amyloidosis and cardiac sarcoidosis, with great confidence. We expect to improve recognition and promote the application of such advanced techniques in the imaging and management of these potentially lethal cardiomyopathies.

Myocardial Involvement in Patients With Histologically Diagnosed Cardiac Sarcoidosis: A Systematic Review and Meta-Analysis of Gross Pathological Images From Autopsy or Cardiac Transplantation Cases

Background

In patients with suspected cardiac sarcoidosis, late gadolinium enhancement on cardiovascular magnetic resonance imaging and/or ¹⁸F‐fluorodeoxyglucose uptake on positron emission tomography are often used to reach a clinical diagnosis of cardiac sarcoidosis. On the basis of data from the imaging literature of clinical cardiac sarcoidosis, no specific features of myocardial involvement are regarded as pathognomonic for cardiac sarcoidosis. Thus, a diagnosis of cardiac sarcoidosis is challenging to make. There has been no systematic analysis of histologically diagnosed cardiac sarcoidosis for patterns of myocardial involvement. We hypothesized that certain patterns of myocardial involvement are more frequent in histologically diagnosed cardiac sarcoidosis.

Methods and Results

We performed a systematic review and meta‐analysis of gross pathological images from the published literature of patients with histologically diagnosed cardiac sarcoidosis who underwent autopsy or cardiac transplantation. Thirty‐three eligible articles provided images of 49 unique hearts. Analysis of these hearts revealed certain features of myocardial involvement in >90% of cases: left ventricular (LV) subepicardial, LV multifocal, septal, and right ventricular free wall involvement. In contrast, other patterns were seen in 0% to 6% of cases: absence of gross LV myocardial involvement, isolated LV midmyocardial involvement, isolated LV subendocardial involvement, isolated LV transmural involvement, absence of septal involvement, or isolated involvement of only one LV level.

Conclusions

In this systematic review and meta‐analysis of histologically diagnosed cardiac sarcoidosis, we identified certain features of myocardial involvement that occurred frequently and others that occurred rarely or never. These patterns could aid the interpretation of cardiovascular magnetic resonance imaging and positron emission tomography imaging and improve the diagnosis and the prognostication of patients with suspected cardiac sarcoidosis.

See Editorial Patel et al

Indirect pathological indicators for cardiac sarcoidosis on endomyocardial biopsy

BACKGROUND

The definitive pathologic diagnosis of cardiac sarcoidosis requires observation of a granuloma in the myocardial tissue. It is common, however, to receive a "negative" report for a clinically probable case. We would like to advise pathologists and clinicians on how to interpret "negative" biopsies.

METHODS

Our study samples were 27 endomyocardial biopsies from 25 patients, three cardiac transplantation and an autopsied heart with suspected cardiac sarcoidosis. Pathologic, radiologic, and clinical features were compared.

RESULTS

The presence of micro-granulomas or increased histiocytic infiltration was always (6/6 or 100%) associated with fatty infiltration and confluent fibrosis, and they showed radiological features of sarcoidosis. Three of five cases (60%) with fatty change and confluent fibrosis were probable for cardiac sarcoidosis on radiology. When either confluent fibrosis or fatty change was present, one-third (3/9) were radiologically probable for cardiac sarcoidosis. We interpreted cases with micro-granuloma as positive for cardiac sarcoidosis (five of 25, 20%). Cases with both confluent fibrosis and fatty change were interpreted as probable for cardiac sarcoidosis (seven of 25, 28%). Another 13 cases, including eight cases with either confluent fibrosis or fatty change, were interpreted as low probability based on endomyocardial biopsy.

CONCLUSIONS

The presence of micro-granuloma could be an evidence for positive diagnosis of cardiac sarcoidosis. Presence of both confluent fibrosis and fatty change is necessary for probable cardiac sarcoidosis in the absence of granuloma. Either of confluent fibrosis or fatty change may be an indirect pathological evidence but they are interpreted as nonspecific findings.

The Multi-modality Cardiac Imaging Approach to Cardiac Sarcoidosis

BACKGROUND

Sarcoidosis is a multisystem granulomatous disease with a neglected but high prevalence of life-threatening cardiac involvement.

DISCUSSION

The clinical presentation of Cardiac Sarcoidosis (CS) depends upon the location and extent of the granulomatous inflammation, with left ventricular free wall the most common location followed by interventricular septum. The lack of a diagnostic gold standard and the unpredictable risk of sudden cardiac death pose serious challenges for the validation of accurate and effective screening test and the management of the disease. In the last few years advanced cardiac imaging modalities such as Cardiac Magnetic Resonance (CMR) and Positron Emission Tomography (PET) have significantly improved our knowledge and understanding of CS, and have also contributed in risk stratification, assessment of inflammatory activity and therapeutic monitoring of the disease.

CONCLUSION

In this review, we will discuss the state of the art in the diagnosis of CS focusing on the role and importance of multi-modality cardiac imaging.

Idiopathic giant cell myocarditis or cardiac sarcoidosis? A retrospective audit of a nationwide case series

Aims

Cardiac sarcoidosis (CS) and giant cell myocarditis (GCM) are inflammatory cardiomyopathies sharing histopathological and clinical features. Their differentiation is difficult and susceptible of confusion and apparent mistakes. The possibility that they represent different phenotypes of a single disease has been debated.

Methods and results

We made a retrospective audit of 73 cases of GCM diagnosed in Finland since the late 1980s. All available histological material was reanalyzed as were other examinations pertinent to the distinction between GCM and CS. Finding granulomas in or outside the heart was considered diagnostic of CS and exclusive of GCM. Altogether 45 of the 73 cases of GCM (62%) were reclassified as CS. In all except one case, this was based on finding sarcoid granulomas that either had been originally missed (n = 29) or misinterpreted (n = 11) or were found in additional posttransplant myocardial specimens (n = 3) or samples of extracardiac tissue (n = 1) accrued over the disease course. Supporting the reclassification, patients relocated to the CS group had less heart failure at presentation (prevalence 20% vs. 46%, P = 0.017) and better 1 year transplant‐free survival (82% vs. 45%, P = 0.011) than patients considered to represent true GCM.

Conclusions

Recognizing granulomas in or outside the heart remains a challenge for the pathologist. Given that CS and GCM are considered distinct diseases and granulomas exclusive of GCM, many cases of GCM, if thoroughly scrutinized, may need reclassification as CS. However, whether CS and GCM are truly different entities or parts of a one‐disease continuum has not yet been conclusively settled.

Review: Contrast-enhanced magnetic resonance in the diagnosis and management of cardiac sarcoidosis

Sarcoidosis is a relatively rare inflammatory condition which potentially carries high morbidity and substantial mortality. Due to the fact that it does not subject patients to ionizing radiation, has high temporal, spatial and contrast resolutions, cardiovascular magnetic resonance imaging (CMR) has become an important diagnostic and prognostic modality in the evaluation for cardiac involvement in this condition. This review provides relevant clinical and pathophysiological background on cardiac sarcoidosis, whilst detailing the role of CMR imaging in the diagnosis, and management of this condition.

The Many Faces of Cardiac Sarcoidosis

OBJECTIVES

The objective of this study was to review and illustrate the sometimes diagnostically challenging features of cardiac sarcoidosis. We emphasize variable phenotypes presented at explant and biopsy evaluation and review literature regarding ancillary clinical and pathologic studies to enhance diagnostic accuracy.

METHODS

A literature review was performed and two cardiac sarcoidosis cases were illustrated.

RESULTS

Our cases and literature review demonstrate the pathologic spectrum of cardiac sarcoidosis. Irregular left ventricular free wall involvement is most common, followed by the interventricular septum and right ventricle. Although granulomas are often composed of tight epithelioid macrophage aggregates, early granulomas comprise loosely associated macrophages with lymphocyte predominance. Chronic disease leads to fibrosis and end-stage heart failure. Sampling errors and variable histology cause low endomyocardial biopsy sensitivity.

CONCLUSIONS

Current guidelines use clinical, radiologic, and immunohistologic criteria for diagnosing cardiac sarcoidosis. Knowledge of these guidelines will assist pathologists in making accurate diagnosis of this disease.

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.

A Multiple Biomarker Approach in Patients with Cardiac Sarcoidosis

Sarcoidosis is a systemic granulomatous disease including heart (cardiac sarcoidosis, CS). It has recently been reported that isolated CS, which presenting primarily cardiac symptoms without clinical evidence of sarcoid involvement in other organs. Diagnostic and prognostic biomarkers of CS, especially in isolated CS, have not yet been established.We studied plasma levels of angiotensin-converting enzyme (ACE), soluble interleukin-2 receptor (sIL-2R), B-type natriuretic peptide (BNP) and cardiac troponin I (cTnI) in consecutive 172 patients with diagnosed sarcoidosis. We compared these markers between non-cardiac sarcoidosis (non-CS, n = 123, 71.5%) and CS patients (n = 49, 28.5%), including non-isolated CS (n = 30, 17.4%) and isolated CS (n = 19, 11.1%). ROC analysis revealed that BNP identified CS with AUC of 0.85 (P < 0.01) in sarcoidosis patients. In addition, ACE and sIL-2R levels were significantly higher in non-isolated CS than in isolated CS (P < 0.05). Furthermore, in the Cox proportional hazard analysis, cTnI, but not ACE, IL2R or BNP, was a predictor of fatal arrhythmia in sarcoidosis patients (HR 2.418, P = 0.003).Higher ACE and sIL2-R are associated with systemic lesions, whereas BNP is a useful marker for detecting cardiac involvement in sarcoidosis patients. cTnI is a predictor of fatal arrhythmia in CS patients. A multiple biomarker approach supports comprehensive management of sarcoidosis.

A Case of Severe Cardiac Sarcoidosis with Minimal Pulmonary Involvement: A Case Report with Literature Review

Sarcoidosis is a granulomatous disease of unknown etiology. Although sarcoidosis is a systemic disease, there appears to be a predilection for involvement of certain organs. The pulmonary system is the most commonly affected system among all racial groups. Cardiac and respiratory complications are the leading causes of death due to sarcoidosis and in certain patient populations about half of these deaths are attributed to cardiac sarcoidosis. There are few autopsy case reports of cardiac sarcoidosis with minimal respiratory involvement making this case report relevant to the importance of the recognition and awareness of this entity. Acad Forensic Pathol. 2018 8(2): 407-415.

A complete heart block in a young male: a case report and review of literature of cardiac sarcoidosis

Cardiac sarcoidosis is one of the uncommon causes of heart failure. Generally, it presents in the form of varying clinical manifestations ranging from asymptomatic to fatal arrhythmias such as ventricular tachycardia and complete heart block. It is difficult to make a diagnosis strictly based on clinical grounds. However, in the setting of extracardiac sarcoidosis and patients presenting with advanced heart block or ventricular arrhythmia, direct cardiac involvement should be suspected. The definitive diagnosis of cardiac sarcoidosis can be made from endomyocardial biopsy, but it is falling out of favor due to patchy myocardial involvement, considerable procedure-related risks, and advancement in additional imaging modalities. Once cardiac sarcoidosis has been diagnosed, management of the disease remains challenging. Steroids are considered the mainstay of therapy, and implantable cardioverter defibrillator therapy can be considered in a selected group of patients at greater risk for malignant ventricular arrhythmias.

Giant Cell Myocarditis: A Brief Review

Giant cell myocarditis (GCM) is a rapidly progressive and frequently fatal disease that mainly affects young to middle-aged previously healthy individuals. Early diagnosis is critical, as recent studies have shown that rapidly instituted cyclosporine-based immunosuppression can reduce inflammation and improve transplant-free survival. Before the 1980s, GCM was mainly a diagnosis made at autopsy. Owing to advancements in diagnostic and therapeutic options, it is now increasingly diagnosed on the basis of endomyocardial biopsies, explanted hearts, or apical wedge sections removed at the time of ventricular assist device placement. Histologic examination remains the gold standard for diagnosis; however, there are many possible etiologies for cardiac giant cells. Having a working knowledge of the clinicopathologic features that distinguish GCM from other giant cell-containing lesions is essential, since such lesions can have widely divergent management and outcome.

Regional myocardial damage and active inflammation in patients with cardiac sarcoidosis detected by non-invasive multi-modal imaging

AIMS

Cardiac sarcoidosis (CS) can be diagnosed using ¹⁸F-FDG-PET/CT (PET), cardiovascular magnetic resonance (CMR), and ¹²³I-BMIPP/²⁰¹TlCl dual myocardial SPECT. This study aims to clarify the relationships among the three modalities with respect to CS.

METHODS AND RESULTS

We evaluated 16 patients (male n = 11; age 55 ± 13 years) with confirmed CS who underwent PET, CMR, and dual SPECT with gated SPECT before starting steroid therapy. The left ventricular myocardium was divided into 17 segments to obtain SUVmax for PET images, defect scores from 0 to 4 (0 normal; 4 absent), and mismatch scores for dual SPECT (BMDS, TLDS, and MS) images and late gadolinium enhancement (LGE) scores (0 none; 1 partly positive; 2 homogeneous) on CMR images. Summed BMDS, TLDS, and MS were 18.6 ± 12.6, 12.9 ± 10.9, and 5.7 ± 3.1, respectively. The segmental BMDS and TLDS scores became significantly higher as the LGE scores increased. The MS scores were significantly higher in areas of LGE with a score of 1 than 0 (both, p < 0.001), but did not significantly differ between areas with LGE scores of 1 and 2. The SUVmax was significantly higher in LGE areas with a score of 1 than 0 (p < 0.025), but did not significantly differ between those with scores of 1 or 2.

CONCLUSION

Regions with a higher SUVmax indicating active myocardial inflammation were mainly located in areas with LGE, where BMIPP and TL mismatches were evident in patients with CS.

Cardiac sarcoidosis with severe involvement of the right ventricle: a case report

We present the case of a patient who underwent cardiac transplantation with the diagnosis of idiopathic dilated cardiomyopathy. Once the explanted heart was examined, a type of granulomatous myocarditis compatible with cardiac sarcoidosis was observed. However, there was severe involvement of the right ventricle, with markedly reduced width of the muscular layer and extensive fibrofatty replacement, findings similar to the ones encountered in cases of arrhythmogenic right ventricular cardiomyopathy (ARVC). Confocal immunofluorescence analysis revealed a reduced signal for plakoglobin and desmoplakin at the cardiac intercalated disks. The immunoreactive signal for desmin showed the typical sarcomeric distribution but not a concentrated signal at the intercalated disks, a pattern previously seen in an 11-year-old girl with Carvajal syndrome bearing a C-terminal truncating mutation in the desmoplakin gene. This case illustrates the difficult and challenging work involved in performing a differential diagnosis among idiopathic dilated cardiomyopathy, isolated cardiac sarcoidosis, and ARVC, all of which are clinical entities known to masquerade as one another.

Sarcoidosis and the heart: A review of the literature

Sarcoidosis is a chronic multisystem disorder without any defined etiology. Cardiac sarcoidosis (CS) is detected in 2-7% of patients with sarcoidosis and more than 20% of the cases of sarcoidosis are clinically silent. Cardiac involvement in systemic sarcoidosis (SS) and isolated cardiac sarcoidosis (iCS) are associated with arrhythmia and severe heart failure (HF) and have a poor prognosis. Early diagnosis of CS and prompt initiation of corticosteroid therapy with or without other immunosuppressants is crucial. Electrocardiography, Holter monitoring, and Doppler echocardiography with speckle tracking imaging can serve as the initial steps to diagnosis of CS. Cardiac magnetic resonance (CMR) imaging and positron emission tomography (PET) are promising techniques for both diagnosis and follow-up of CS. This review discusses the main aspects of cardiac involvement in sarcoidosis.

Right ventricular cardiomyopathy meeting the arrhythmogenic right ventricular dysplasia revised criteria? Don't forget sarcoidosis!

A 53-year-old woman was referred for ventricular fibrillation with resuscitation. A CT-angiography showed signs of a right ventricular enlargement without obvious cause. A cardiac MRI demonstrated a dilated and hypokinetic right ventricle with extensive late gadolinium enhancement. Arrhythmogenic right ventricular dysplasia (ARVD) was suspected according to the "revised ARVD task force criteria". An endomyocardial biopsy was inconclusive. The patient developed purulent pericarditis after epicardial ablation therapy and died of toxic shock syndrome. The post-mortem pathologic examination demonstrated sarcoidosis involving the heart, lungs, and thyroid gland.

Sudden cardiac death due to coronary artery dissection as a complication of cardiac sarcoidosis

Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome (ACS), cardiac tamponade and sudden cardiac death that typically affects young women in the postpartum period. Rarely, it can be caused by systemic inflammatory conditions such as sarcoidosis. Sarcoidosis is an inflammatory disease most often affecting the lung and lymph nodes that can sometimes affect the heart. The authors report a case of sudden cardiac death caused by SCAD in the context of undiagnosed and subclinical cardiac sarcoidosis. The decedent was a 47-year-old male with a relatively innocuous past medical history. He was found dead in bed. At autopsy, there was a lethal hemopericardium resulting in cardiac tamponade. Gross examination of the heart revealed dissection of the posterior descending coronary branch of the right coronary artery. Histologically, the coronary artery showed acute and organizing dissection with evidence of vasculitis. A chronic inflammatory infiltrate consisting of lymphocytes, histiocytes, eosinophils and giant cells was seen. Sections of the myocardium showed myocarditis with a nonnecrotizing granuloma. The death was attributed to cardiac tamponade secondary to SCAD in the context of systemic sarcoidosis. The presented case demonstrates two concurrent rare pathologies and highlights the importance of considering SCAD in cases of sudden cardiac death at autopsy.

Isolated cardiac sarcoidosis: clinical characteristics, diagnosis and treatment

Sarcoidosis is a systemic disease characterized by the development of noncaseating epithelioid granulomas in multiple organs. Despite extensive investigations over a long period of time, the etiology of this disease remains unknown. Cardiac involvement of this disease is the most ominous complication leading to fatal outcome. Recently, attention has been focused on isolated cardiac sarcoidosis, which exists without clinically apparent sarcoidosis elsewhere. One of the critical issues of isolated cardiac sarcoidosis is difficulty in diagnosis, since existence of the cardiac lesion should be detected from cardiac manifestations alone. Because specificity of biomarkers or sensitivity of histological examination of biopsied sample is very low, diagnosis of isolated cardiac sarcoidosis mainly depends on imaging modalities. In this review article we summarized current knowledge on the pathogenesis of sarcoidosis, clinical features of cardiac sarcoidosis especially that isolated to the heart by showing some typical cases. Utilities and problems of diagnostic imaging tests for this condition including echocardiography, cardiac magnetic resonance imaging, and fluorodeoxyglucose-positron emission tomography are discussed. Advances in pharmacological and nonpharmacological treatment for cardiac sarcoidosis have improved the prognosis of cardiac sarcoidosis to a great deal; however, there are many issues that remain to be solved in the management of isolated cardiac sarcoidosis.

Morphologic features of cardiac sarcoidosis in native hearts of patients having cardiac transplantation

Described herein are 10 patients who underwent cardiac transplantation (CT) for severe chronic systolic heart failure resulting from cardiac sarcoidosis. None had the diagnosis of sarcoidosis established before CT except for the 3 patients who earlier had had a portion of left ventricular wall excised for insertion of a left ventricular assist device and non-caseating granulomas were present in the removed myocardium. Although none of the 10 patients had significant narrowing of any of the epicardial coronary arteries, all had focal scarring of the walls of the left and right ventricles and ventricular septum and all had dilated ventricular cavities. The patients with the most ventricular wall scarring tended to have the fewest sarcoid granulomas in the ventricular walls. Two patients had no sarcoid granulomas in the excised heart although one did have typical sarcoid granulomas in the portion of left ventricular wall excised to insert a left ventricular assist device. Patients with cardiac sarcoidosis severe enough to warrant CT had characteristic cardiac ventricular morphologic findings, and no dysfunction of other non-cardiac organs, making clinical diagnosis of cardiac sarcoidosis rather difficult.

Combination drug therapy for patients with intractable ventricular tachycardia associated with right ventricular cardiomyopathy

BACKGROUND

Drug therapy for patients with right ventricular (RV) cardiomyopathy refractory to single-drug therapy and ablation has not been well defined.

METHODS

We reviewed our entire RV cardiomyopathy database (31 patients) and found four patients presenting with ventricular arrhythmias of RV origin refractory to single-drug therapy. These patients underwent complete evaluation for arrhythmogenic right ventricular cardiomyopathy (ARVC).

RESULTS

Following the revised 2010 task force criteria, of these four patients, three were diagnosed with ARVC, and one with cardiac sarcoidosis. These patients proved to be refractory to drug monotherapy and either failed or deemed to not be candidates for endocardial ablation. Their arrhythmias were ultimately controlled with combinations of sotalol, flecainide, and mexiletine.

CONCLUSIONS

In our experience, combination drug therapy is an effective treatment strategy for patients with ventricular tachycardia refractory to monotherapy and, in some cases, ablation. In addition, flecainide appears to be safe and effective for those with RV cardiomyopathy without significant left ventricular dysfunction.

Correlation of late gadolinium enhancement MRI and quantitative T2 measurement in cardiac sarcoidosis

PURPOSE

To investigate the potentially improved detection and quantification of cardiac involvement using novel late-gadolinium-enhancement (LGE) cardiac magnetic resonance imaging (MRI) and quantitative T2 measurement to achieve better myocardial tissue characterization in systemic sarcoidosis.

MATERIALS AND METHODS

Twenty-eight patients with systemic sarcoidosis underwent a cardiac magnetic resonance imaging (CMR) study on a 1.5T system. Precontrast CMR included left ventricular (LV) and right ventricular (RV) function and quantitative T2 measurement. Postcontrast LGE-MRI included inversion-recovery fast-gradient-echo (IR-FGRE) and multicontrast late-enhancement imaging (MCLE).

RESULTS

LV functional parameters were normal in all patients (LVEF=61.2±8.5%) including with cardiac involvement (LVEF=59.4±12.1%) and without (LVEF=61.7±7.5%) while the average RV function was comparatively decreased (RVEF=48.0±6.6%, P<0.0001). 21.4% of patients had cardiac involvement showing patchy or multiple focal hyperenhancement patterns in LV free wall, papillary muscles (PM), or interventricular septum. In two cases with PM involvement, the PM abnormal LGE foci were only observed on MCLE. For precontrast T2 measurements, a significantly decreased T2 measurement was observed in regions demonstrating LGE, compared to the LGE-negative group (focal LGE-positive regions vs. negative: 40.0±2.4 msec vs. 53.0±2.6 msec, P<0.0001).

CONCLUSION

LGE-MRI can identify cardiac involvement in systemic sarcoidosis. MCLE might be more sensitive at detecting subtle myocardial lesion. The decreased T2 observed in cardiac sarcoid may reflect its inactive phase, thus might provide a noninvasive method for monitoring disease activity or therapy.

Diffuse diseases of the myocardium: MRI-pathologic review of cardiomyopathies with dilatation

OBJECTIVE

In this radiologic-pathologic review of the cardiomyopathies, we present the pertinent imaging findings of diffuse myocardial diseases that are associated with ventricular dilatation, including ischemic cardiomyopathy, nonischemic dilated cardiomyopathy, cardiac sarcoidosis, and iron overload cardiomyopathy.

CONCLUSION

Correlation of the key radiologic findings with gross and microscopic pathologic features is presented, to provide the reader with a focused and in-depth review of the pathophysiology underlying each entity and the basis for the corresponding imaging characteristics.