Prevalence of cardiac sarcoidosis in patients presenting with monomorphic ventricular tachycardia

Diagnostic and management strategies in cardiac sarcoidosis

Cardiac sarcoidosis (CS) is increasingly recognized in the context of with otherwise unexplained electrical or structural heart disease due to improved diagnostic tools and awareness. Therefore, clinicians require improved understanding of this rare but fatal disease to care for these patients. The cardinal features of CS, include arrhythmias, atrio-ventricular conduction delay and cardiomyopathy. In addition to treatments tailored to these cardiac manifestations, immunosuppression plays a key role in active CS management. However, clinical trial and consensus guidelines are limited to guide the use of immunosuppression in these patients. This review aims to provide a practical overview to the current diagnostic challenges, treatment approach, and future opportunities in the field of CS.

The role of ICDs in patients with sarcoidosis-A comprehensive review

BACKGROUND

Implantable cardioverter defibrillator (ICD) use in cardiac sarcoidosis (CS) to prevent sudden cardiac death (SCD) is a potentially life-saving intervention. However, the factors that determine outcome in this cohort remains largely unknown. This review analyses CS patients with an ICD and highlights determinants of poor outcome.

OUTCOMES

Analysis of studies which used the 2014 HRS Consensus, 2017 AHA/ACC/HRS Guideline and 2022 ESC Guidelines showed that those with class I recommendations have higher incidences of ventricular arrhythmia (VA) than those with class II recommendations. Additionally, even those with normal left ventricular ejection fraction (LVEF) and CS are at high risk of VA and SCD.

SUMMARY

Compounding research emphasises the importance of cardiac imaging in those with sarcoidosis, with evidence to suggest a possible need for revision of the guidelines. Other variables such as demographics and ventricular characteristics may prove useful in predicting those to benefit most from ICD insertion.

Prevalence of Cardiac Sarcoidosis in Middle-Aged Adults Diagnosed with High-Grade Atrioventricular Block

INTRODUCTION

Atrioventricular block may be idiopathic or a secondary manifestation of an underlying systemic disease. Cardiac sarcoidosis is a significant underlying cause of high-grade atrioventricular block, posing diagnostic challenges and significant clinical implications. This study aimed to assess the prevalence and clinical characteristics of cardiac sarcoidosis among younger patients presenting with unexplained high-grade atrioventricular block.

METHODS

We evaluated patients aged between 18 and 65 years presenting with unexplained high-grade atrioventricular block, who were systematically referred for cardiac magnetic resonance imaging, positron emission tomography-computed tomography, or both, prior to pacemaker implantation. Subjects with suspected cardiac sarcoidosis based on imaging findings were further referred for tissue biopsy. Cardiac sarcoidosis diagnosis was confirmed based on biopsy results.

RESULTS

Overall, 30 patients with high-grade atrioventricular block were included in the analysis. The median age was 56.5 years (interquartile range 53-61.75, years). In 37%, cardiac magnetic resonance imaging, positron emission tomography-computed tomography, or both, were suggestive of cardiac sarcoidosis, and in 33% cardiac sarcoidosis was confirmed by tissue biopsy. Compared with idiopathic high-grade atrioventricular block patients, all cardiac sarcoidosis patients were males (100% vs 60%, P = .029), were more likely to present with heart failure symptoms (50% vs 10%, P = .047), had thicker inter-ventricular septum on echocardiography (12.2 ± 2.7 mm vs 9.45 ± 1.6 mm, P = .002), and were more likely to present with right ventricular dysfunction (33% vs 10%, P = .047).

CONCLUSIONS

Cardiac sarcoidosis was confirmed in one-third of patients ≤ 65 years, who presented with unexplained high-grade atrioventricular block. Cardiac sarcoidosis should be highly suspected in such patients, particularly in males who present with heart failure symptoms or exhibit thicker inter-ventricular septum and right ventricular dysfunction on echocardiography.

Predictors of Mortality in Sarcoidosis

Sarcoidosis is a systemic granulomatous disorder that affects individuals of all racial/ethnic origins and occurs at any time of life. Spontaneous remission is frequent and may occur in 2 of 3 patients, while the remaining cases have chronic, progressive disease, with some patients presenting with organ- and life-threatening involvements. Many reports have investigated which features may be related to poor outcomes in patients with sarcoidosis. Pulmonary hypertension and respiratory failure from pulmonary fibrosis are the most common complications associated with the cause of death in sarcoidosis. Other major causes of death include cardiac, neurologic, hepatic involvement, and hemoptysis from aspergilloma.

[Imaging diagnostics of cardiac sarcoidosis]

Cardiac involvement is clinically apparent in approximately 5% of all patients with systemic sarcoidosis, whereas evidence of cardiac involvement by imaging studies can be found in approximately 20% of cases. Occasionally, isolated cardiac sarcoidosis is encountered and is the only sign of the disease. The most frequent cardiac manifestations of the multifocal granulomatous inflammation include atrioventricular (AV) blocks and other conduction disorders, ventricular arrhythmias, sudden cardiac death and left and right ventricular wall disorders. Accordingly, symptoms that should raise suspicion include palpitations, lightheadedness and syncope. The diagnostic approach to cardiac sarcoidosis is not straightforward. Typical echocardiographic findings include regional thinning and contraction abnormalities particularly in basal, septal and lateral locations. Infrequently, myocardial hypertrophy may be present; however, the sensitivity of echocardiography is low and cardiac sarcoidosis can be present even when an echocardiogram is unrevealing. Cardiac magnetic resonance imaging (MRI) frequently shows late gadolinium enhancement (LGE) in a multifocal pattern often involving the basal septum and lateral walls. The sensitivity and specificity of MRI for detecting cardiac sarcoidosis are high. Fluorodeoxyglucose positron emission tomography (FDG-PET) plays an important role in the diagnostic algorithm due to its ability to visualize focal inflammatory activity both in the myocardium and in extracardiac locations. This may help target the optimal location for biopsy in order to obtain histologic proof of sarcoidosis and can also be used to follow the response to anti-inflammatory treatment. Notably, the sensitivity of endomyocardial biopsy is poor due to the patchy nature of myocardial involvement. In clinical practice, either histologic evidence of noncaseating granulomas from the myocardium or evidence from extracardiac tissue in combination with typical cardiac imaging findings are required to establish the diagnosis.

Management of the arrhythmic manifestations of cardiac sarcoidosis

Cardiac sarcoidosis (CS) is characterised by a high burden of arrhythmic manifestations and cardiac electrophysiologists play an important role in both the diagnosis and management of this challenging condition. CS is characterised by the formation of noncaseating granulomas within the myocardium, which can subsequently lead to fibrosis. Clinical presentations of CS are varied and depend on the location and extent of granulomas. Patients may present with atrioventricular block, ventricular arrhythmias, sudden cardiac death or heart failure. CS is being increasing diagnosed through use of advanced cardiac imaging, however endomyocardial biopsy is often still required to confirm the diagnosis. Due to the low sensitivity of fluoroscopy-guided right ventricular biopsies, three-dimensional electro-anatomical mapping and electrogram-guided biopsies are being investigated as a means to improve diagnostic yield. Cardiac implantable electronic devices are often required in the management of CS, either for pacing or for primary or secondary prevention of ventricular arrhythmias. Catheter ablation for ventricular arrythmias may also be required, although this is often associated with high recurrence rates due to the challenging nature of the arrhythmogenic substrate. This review will explore the underlying mechanisms of the arrhythmic manifestations of CS, provide an overview of current clinical practice guidelines, and examine the important role that cardiac electrophysiologists play in managing patients with CS.

Outcomes of catheter ablation for ventricular tachycardia in patients with sarcoidosis: Insights from the National Inpatient Sample database (2002-2018)

INTRODUCTION

Data on utilization, major complications, and in-hospital mortality of catheter ablation (CA) for sarcoidosis-related ventricular tachycardia (VT) are limited. We sought to determine the outcomes of sarcoidosis-related VT, and incidence and predictors of complications associated with the CA procedure.

METHODS

We queried the 2002-2018 National Inpatient Sample database to identify patients aged ≥18 years with sarcoidosis admitted with VT. A 1:3 propensity score-matched (PSM) analysis was used to compare patient outcomes between CA and medically managed groups. Multivariable regression was performed to determine independent predictors of in-hospital mortality and procedural complications associated with the CA procedure.

RESULTS

Of 3220 sarcoidosis patients with VT, 132 (4.1%) underwent CA. Patients who underwent CA were younger, male predominant, more likely Caucasian, had differences in baseline comorbidities including more likely to have heart failure, less likely to have prior myocardial infarction, COPD, or severe renal disease, had a higher mean household income, and more likely admitted to a larger/urban teaching hospital. After PSM, we examined 106 CA cases and 318 medically managed cases. There was a trend toward a lower in-hospital mortality rate in the CA group when compared to the medically managed group (1.9% vs. 6.6%, p = 0.08). The most common complications were pericardial drainage (5.3%), postoperative hemorrhage (3.8%), accidental puncture periprocedure (3.0%), and cardiac tamponade (2.3%). Independent predictors of in-hospital mortality and procedural complications among the CA group included congestive heart failure (odds ratio [OR], 13.2; 95% confidence interval [CI], 1.7-104.2) and mild to moderate renal disease (OR, 3.9; 95% CI, 1.1-13.3).

CONCLUSIONS

Compared to patients with sarcoidosis-related VT who received medical therapy alone, those who underwent CA have a trend for a lower mortality rate despite procedure-related complications occurring as high as 9.1%. Additional studies are recommended to better evaluate the benefits and risks of VT ablation in this group.

Atrial depolarization abnormalities in pulmonary sarcoidosis

BACKGROUND

Cardiac sarcoidosis, often manifested as sudden death, can be the first manifestation of sarcoidosis. Since 12-lead electrocardiogram (ECG) is recommended as an initial screening tool for cardiac sarcoidosis, the recognition of subtle abnormalities assumes utmost significance. The objective of this study was to identify the electrocardiographic abnormalities in patients with pulmonary sarcoidosis.

RESULTS

A detailed analysis of 12-lead ECGs obtained from sixty patients with histopathologically proven pulmonary sarcoidosis and no overt cardiac involvement was done. The findings were compared with those of an age-matched control group. Varying degrees of intraventricular conduction defects were common in the study group [67%], as well as the control group [57%] [P = 0.23]. There was a higher prevalence of biphasic P wave [P = 0.003] and bifid P wave [P = 0.029] in lead III and rsr' in lead aVF [P = 0.03] in the study group as compared to the control group.

CONCLUSIONS

Our study demonstrates a greater prevalence of subtle ECG abnormalities in patients with pulmonary sarcoidosis as compared to patients with other forms of pulmonary disease. Atrial depolarization abnormalities were commoner in patients with pulmonary sarcoidosis.

The prognostic value of positron emission tomography in the evaluation of suspected cardiac sarcoidosis

OBJECTIVES

To assess the prognostic value of positron emission tomography (PET) imaging in patients undergoing evaluation for known or suspected cardiac sarcoidosis (CS) while not on active immunotherapy.

BACKGROUND

Previous studies have attempted to identify the value of PET imaging to aid in risk stratification of patients with CS, however, most cohorts have included patients currently on immunosuppression, which may confound scan results by suppressing positive findings.

METHODS

We retrospectively analyzed 197 patients not on immunosuppression who underwent 18F-fluorodeoxyglucose (FDG) PET scans for evaluation of known or suspected CS. The primary endpoint of the study was time to ventricular arrhythmia (VT/VF), or death. Candidate predictors were identified by univariable Cox proportional hazards regression. Independent predictors were identified by performing multivariable Cox regression with stepwise forward selection.

RESULTS

Median follow-up time was 531 [IQR 309, 748] days. 41 patients met the primary endpoint. After stepwise forward selection, left ventricular ejection fraction (LVEF) (HR 0.98, 95% CI 0.96-0.99, P = 0.02), history of VT/VF (HR 4.19, 95% CI 2.15-8.17, P < 0.001), and summed rest score (SRS) (HR 1.06, 95% CI 1.02-1.12, P = 0.01) were predictive of the primary endpoint. Quantitative and qualitative measures of FDG uptake on PET were not predictive of clinical events.

CONCLUSIONS

Among untreated patients who underwent PET scans to evaluate known or suspected CS, LVEF, history of VT/VF, and SRS were associated with adverse clinical outcomes.

Long-term, real world experience of ventricular tachycardia and granulomatous cardiomyopathy

BACKGROUND

Granulomatous cardiomyopathy(GCM) is relatively uncommon in patients presenting with ventricular tachycardia(VT). Sarcoidosis and tuberculosis are the most common causes of GCM with VT. The aim of study was to evaluate their clinical characteristics and the long-term outcomes.

METHODS

We retrospectively analyzed patients from March 2004 to January 2020, presenting with VT and subsequently diagnosed to have GCM. Patients were divided into three groups (sarcoid, tuberculosis and indeterminate) based on serologic tests, imaging and histopathology. The response to anti-arrhythmic and disease specific therapy on long-term follow-up were analysed.

RESULTS

There were 52 patients, comprising 27 males and 25 females, age 40 ± 10 years. The follow-up period was 5.9 ± 3.9 years. Sarcoidosis was diagnosed in 20(38%); tuberculosis(TB) in 15(29%) and 17(33%) patients were indeterminate. Left ventricular ejection fraction(LVEF) of the entire cohort was 0.45 ± 0.14. Erythrocyte Sedimentation Rate(ESR) was found to be significantly higher in TB(43.6 ± 18.4) patients vs sarcoid(18.9 ± 6.7)p < 0.0001, but not the indeterminate group(36.2 ± 21.1), p = 0.3. Implantable Cardioverter Defibrillator(ICD) implantation was performed in 12/20(60%) patients in the sarcoid group, in 4/15(27%) patients in the TB group and in 10/17(59%) patients in the indeterminate group. At a mean follow-up of six years, VT recurrences were noted in 6, 2, and 7 patients in the sarcoid, TB and indeterminate groups respectively.

CONCLUSION

Despite the advances in diagnostic modalities for tuberculosis and sarcoidosis, in real-world practice, almost one-third of the patients with VT and GCM have uncertain etiology. Long term outcomes of patients presenting with GCM and VT with mild left ventricle dysfunction treated appropriately seems favorable.

Phenotypic and HLA-DRB1 allele characterization of Swedish cardiac sarcoidosis patients

BACKGROUND

Early detection and initiation of treatment in cardiac sarcoidosis (CS) is believed to be crucial to reduce morbidity and mortality. The diagnosis of CS is challenging, especially in isolated CS (ICS). Certain human leukocyte antigen (HLA-DRB1) alleles associate with different phenotypes of sarcoidosis. Phenotypic and genotypic characterization of patients with CS may improve our ability to identify patients being at risk for developing CS.

METHODS

87 patients with CS, identified at two Swedish university hospitals were included. Phenotypic characteristics were extracted from the medical records and the patients were HLA-DRB1 typed.

RESULTS

Median age at diagnosis was 55 years, 37% were women. HLA-DRB1 distribution was similar to a general sarcoidosis population. A majority of patients (51/87) had CS as the first sarcoidosis presentation. They were younger (p = 0.04), more often presenting with ventricular tachycardia (VT) or atrioventricular block (AVB) grade II or III (p < 0.001), had lower left ventricular ejection fraction (LVEF) (p = 0.002), lower serum angiotensin converting enzyme (s-ACE) (p = 0.025), and fewer extra cardiac manifestations (ECM) (p = 0.02) than those presenting with CS later.

CONCLUSIONS

Of Swedish CS patients, 59% presented with cardiac involvement as first manifestation. They had more severe cardiac symptoms than patients presenting with CS later. This phenotype disclosed less ECM and lower s-ACE thus diagnosis can be missed or delayed. We did not observe significant differences in HLA-DRB1 allele frequency between patients with CS compared to sarcoidosis in general. Awareness of CS as a primary manifestation can enable early detection and adequate intervention.

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.

Clinical Presentation and Treatment of High-Risk Sarcoidosis

Sarcoidosis is a multisystem disease of unknown cause with heterogenous clinical manifestations and variable course. Spontaneous remissions occur in some patients while others have progressive disease impacting survival, organ function, and quality of life. Four high-risk sarcoidosis phenotypes associated with chronic inflammation have recently been identified as high-priority areas for research. These include treatment-refractory pulmonary disease, cardiac sarcoidosis, neurosarcoidosis and multiorgan sarcoidosis. Significant gaps currently exist in understanding of these high-risk manifestations of sarcoidosis, including their natural history, diagnostic criteria, biomarkers, and the treatment strategy such as the ideal agent, optimal dose and treatment duration. The use of registries with well-phenotyped patients is a critical first step to study high-risk sarcoidosis manifestations systematically. We review the diagnostic and treatment approach to high-risk sarcoidosis manifestations. Appropriately identifying these disease sub-groups will help enroll well-phenotyped patients in sarcoidosis registries and clinical trials, a necessary step to narrow existing gaps in understanding of this enigmatic disease.

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.

Management of ventricular tachycardia in patients with cardiac sarcoidosis

Sarcoidosis is a multisystem granulomatous disease with 2 different phases (inflammation and scar). In the current era of targeted use of implantable cardioverter-defibrillators and modern heart failure therapy, recent data indicate the prognosis of cardiac sarcoidosis (CS) is much improved, and hence more patients are presenting with recurrent ventricular tachycardia (VT). This review highlights our current understanding of the pathophysiology and management of ventricular arrhythmias in CS with the major focus on indications, techniques, and outcomes of ablation. It is likely macroreentry phenomena around areas of fibrosis is the most frequent mechanism of ventricular arrhythmia in CS. It is also possible that inflammation may play a role in initiating reentry with ventricular ectopy in CS patients, or by slowing conduction in diseased tissue. The best available data would suggest annual rates of VT of perhaps 1%-2% and 10%-15% in patients with initially clinically silent and clinically manifest disease, respectively. Current guidelines recommend a stepwise approach to VT management. The first suggested step is treatment with immunosuppression if there is evidence of active inflammation. Antiarrhythmic medications are often started at the same time, with catheter ablation considered if VT cannot be controlled. Activation and entrainment mapping and ablation are favored in the setting of hemodynamically tolerated VT. Substrate ablation targets areas of abnormal electrogram and favorable pace mapping using linear and/or cluster lesion sets with the goal of abolishing critical isthmuses and/or blocking VT exit sites. Epicardial mapping ablation is required in 20%-35% of cases. In general, more morphologies of VT are induced (often 3-4) and subsequent outcomes (recurrence rates 40%-50%) are less favorable than in other forms of nonischemic cardiomyopathy. The prognosis of CS is much improved and, as a result, more patients are developing VT during follow-up. Likely principally related to the complex disease substrate, VT ablation is technically challenging, with moderate outcomes, and much remains to be learned.

Sarcoidosis-Related Cardiomyopathy: Current Knowledge, Challenges, and Future Perspectives State-of-the-Art Review

The prevalence of sarcoidosis-related cardiomyopathy is increasing. Sarcoidosis impacts cardiac function through granulomatous infiltration of the heart, resulting in conduction disease, arrhythmia, and/or heart failure. The diagnosis of cardiac sarcoidosis (CS) can be challenging and requires clinician awareness as well as differentiation from overlapping diagnostic phenotypes, such as other forms of myocarditis and arrhythmogenic cardiomyopathy. Clinical manifestations, extracardiac involvement, histopathology, and advanced cardiac imaging can all lend support to a diagnosis of CS. The mainstay of therapy for CS is immunosuppression; however, no prospective clinical trials exist to guide management. Patients may progress to developing advanced heart failure or ventricular arrhythmia, for which ventricular assist device therapies or heart transplantation may be considered. The existing knowledge gaps in CS call for an interdisciplinary approach to both patient care and future investigation to improve mechanistic understanding and therapeutic strategies.

The harm of delayed diagnosis of arrhythmogenic cardiac sarcoidosis: a case series

Aims

Cardiac sarcoidosis (CS) is a known cause of ventricular tachycardia (VT). However, an arrhythmogenic presentation may not prompt immediate comprehensive evaluation. We aimed to assess the diagnostic and disease course of patients with arrhythmogenic cardiac sarcoidosis (ACS).

Methods and results

From the Leiden VT-ablation-registry, consecutive patients with CS as underlying aetiology were retrospectively included. Data on clinical presentation, time-to-diagnosis, cardiac function, and clinical outcomes were collected. Patients were divided in early (<6 months from first cardiac presentation) and late diagnosis. After exclusion of patients with known causes of non-ischaemic cardiomyopathy (NICM), 15 (12%) out of 129 patients with idiopathic NICM were ultimately diagnosed with CS and included. Five patients were diagnosed early; all had early presentation with VTs. Ten patients had a late diagnosis with a median delay of 24 (IQR 15–44) months, despite presentation with VT (n = 5) and atrioventricular block (n = 4). In 6 of 10 patients, reason for suspicion of ACS was the electroanatomical scar pattern. In patients with early diagnosis, immunosuppressive therapy was immediately initiated with stable cardiac function during follow-up. Adversely, in 7 of 10 patients with late diagnosis, cardiac function deteriorated before diagnosis, and in only one cardiac function recovered with immunosuppressive therapy. Six (40%) patients died (five of six with late diagnosis).

Conclusion

Arrhythmogenic cardiac sarcoidosis is an important differential diagnosis in NICM patients referred for VT ablation. Importantly, the diagnosis is frequently delayed, which leads to a severe disease course, including irreversible cardiac dysfunction and death. Early recognition, which can be facilitated by electroanatomical mapping, is crucial.

Ten Questions Cardiologists Should Be Able to Answer About Cardiac Sarcoidosis: Case-Based Approach and Contemporary Review

Sarcoidosis is an inflammatory multisystemic disease of unknown etiology characterized by the formation of noncaseating epithelioid cell granulomas. Cardiac sarcoidosis might be life-threatening and its diagnosis and treatment remain a challenge nowadays. The aim of this review is to provide an updated overview of cardiac sarcoidosis and, through 10 practical clinical questions and real-life challenging case scenarios, summarize the main clinical presentation, diagnostic criteria, imaging findings, and contemporary treatment.

Heart Failure, Atrioventricular Block, and Ventricular Tachycardia in Sarcoidosis

Background Sarcoidosis is a granulomatous disease usually affecting the lungs, although cardiac morbidity may be common. The risk of these outcomes and the characteristics that predict them remain largely unknown. This study investigates the epidemiology of heart failure, atrioventricular block, and ventricular tachycardia among patients with and without sarcoidosis. Methods and Results We identified California residents aged ≥21 years using the Office of Statewide Health Planning and Development ambulatory surgery, emergency, or inpatient databases from 2005 to 2015. The risk of sarcoidosis on incident heart failure, atrioventricular block, and ventricular tachycardia were each determined. Linkage to the Social Security Death Index was used to ascertain overall mortality. Among 22 527 964 California residents, 19 762 patients with sarcoidosis (0.09%) were identified. Sarcoidosis was the strongest predictor of heart failure (hazard ratio [HR], 11.2; 95% CI, 10.7-11.7), atrioventricular block (HR, 117.7; 95% CI, 103.3-134.0), and ventricular tachycardia (HR, 26.1; 95% CI, 24.2-28.1) identified among all risk factors. The presence of any cardiac involvement best predicted each outcome. Approximately 22% (95% CI, 18%-26%) of the relationship between sarcoidosis and increased mortality was explained by the presence of at least 1 of these cardiovascular outcomes. Conclusions The magnitude of risk associated with sarcoidosis as a predictor of heart failure, atrioventricular block, and ventricular tachycardia, exceeds all established risk factors. Surveillance for and anticipation of these outcomes among patients with sarcoidosis is indicated, and consideration of a sarcoidosis diagnosis may be prudent among patients with heart failure, atrioventricular block, or ventricular tachycardia.

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.

FDG-PET in possible cardiac sarcoidosis: Right ventricular uptake and high total cardiac metabolic activity predict cardiovascular events

BACKGROUND

Cardiac involvement accounts for the majority of morbidity and mortality in sarcoidosis. Pathological myocardial fluorodeoxyglucose (FDG)-uptake in positron emission tomography (PET) has been associated with cardiovascular events and quantitative metabolic parameters have been shown to add prognostic value. Our aim was to study whether the pattern of pathological cardiac FDG-uptake and quantitative parameters are able to predict cardiovascular events in patients with suspected cardiac sarcoidosis (CS).

METHODS

137 FDG-PET examinations performed in Tampere University Hospital were retrospectively analyzed visually and quantitatively. Location of pathological uptake was noted and pathological metabolic volume, average standardized uptake value (SUV), and total cardiac metabolic activity (tCMA) were calculated. Patients were followed for ventricular tachycardia, decrease in left ventricular ejection fraction, and death.

RESULTS

Eleven patients had one or more cardiovascular events during the follow-up. Five patients out of 12 with uptake in both ventricles had an event during follow-up. Eight patients had high tCMA (> 900 MBq) and three of them had a cardiovascular event. Right ventricular uptake and tCMA were significantly associated with cardiovascular events during follow-up (P-value .001 and .018, respectively).

CONCLUSIONS

High tCMA and right ventricular uptake were significant risk markers for cardiac events among patient with suspected CS.

Arrhythmias Associated with Inflammatory Cardiomyopathies

Purpose of review

To provide an approach to the diagnosis and treatment of arrhythmias associated with inflammatory cardiomyopathies.

Recent findings

Inflammatory cardiomyopathies are increasingly recognized as the etiology of both ventricular and supraventricular arrhythmias. There have been recent studies providing novel insights into the pathogenesis of arrhythmias in inflammatory cardiomyopathies and exploring the role of various diagnostic tools and treatment strategies.

Summary

Patients with inflammatory cardiomyopathies often present with one or more arrhythmias, including atrioventricular block, atrial and ventricular tachyarrhythmias, and occasionally sudden cardiac death. Given dynamic pathophysiology and heterogeneous presentation, the management of arrhythmias in these patients presents unique challenges. We review the current approach to the diagnosis and treatment of arrhythmias in this challenging cohort of patients with an emphasis on cardiac sarcoidosis.

Supplementary Information

The online version of this article (10.1007/s11936-020-00871-5) contains supplementary material, which is available to authorized users.

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.

Cardiac sarcoidosis: A long term follow up study

BACKGROUND

Prognostic factors are lacking in cardiac sarcoidosis (CS), and the effects of immunosuppressive treatments are unclear.

OBJECTIVES

To identify prognostic factors and to assess the effects of immunosuppressive drugs on relapse risk in patients presenting with CS.

METHODS

From a cohort of 157 patients with CS with a median follow-up of 7 years, we analysed all cardiac and extra-cardiac data and treatments, and assessed relapse-free and overall survival.

RESULTS

The 10-year survival rate was 90% (95% CI, 84-96). Baseline factors associated with mortality were the presence of high degree atrioventricular block (HR, 5.56, 95% CI 1.7-18.2, p = 0.005), left ventricular ejection fraction below 40% (HR, 4.88, 95% CI 1.26-18.9, p = 0.022), hypertension (HR, 4.79, 95% CI 1.06-21.7, p = 0.042), abnormal pulmonary function test (HR, 3.27, 95% CI 1.07-10.0, p = 0.038), areas of late gadolinium enhancement on cardiac magnetic resonance (HR, 2.26, 95% CI 0.25-20.4, p = 0.003), and older age (HR per 10 years 1.69, 95% CI 1.13-2.52, p = 0.01). The 10-year relapse-free survival rate for cardiac relapses was 53% (95% CI, 44-63). Baseline factors that were independently associated with cardiac relapse were kidney involvement (HR, 3.35, 95% CI 1.39-8.07, p = 0.007), wall motion abnormalities (HR, 2.30, 95% CI 1.22-4.32, p = 0.010), and left heart failure (HR 2.23, 95% CI 1.12-4.45, p = 0.023). After adjustment for cardiac involvement severity, treatment with intravenous cyclophosphamide was associated with a lower risk of cardiac relapse (HR 0.16, 95% CI 0.033-0.78, p = 0.024).

CONCLUSIONS

Our study identifies putative factors affecting morbidity and mortality in cardiac sarcoidosis patients. Intravenous cyclophosphamide is associated with lower relapse rates.

The ECG in sarcoidosis - a marker of cardiac involvement? Current evidence and clinical implications

Sarcoidosis is a multisystem granulomatous disease of unknown etiology characterized by noncaseating granulomas. Cardiac involvement is often limiting patients' prognosis. Cardiac sarcoidosis can manifest with variant cardiac arrhythmias, of which atrioventricular (AV)-block-related bradycardia and ventricular tachycardias are the most common. Although cardiac sarcoidosis remains a histopathological diagnosis, the significance of imaging modalities, especially cardiac magnetic resonance imaging is increasing rapidly but mainly remains reserved for patients with a high suspicion due to a previous arrhythmia or unknown cardiomyopathy. Thus, there is a need for screening in daily clinical practice so that possible characteristic electrocardiographic (ECG) findings may guide the way to detect the disease. We therefore evaluated the ECG as a potential tool for screening of cardiac sarcoidosis and present different electrophysiological manifestations of cardiac sarcoidosis based on a literature review. The ECG is a valuable tool for screening of cardiac involvement in patients with sarcoidosis. Several parameters have been shown to be associated with cardiac involvement in sarcoidosis such as higher-degree AV-block, QRS complex fragmentation and widening, as well as certain T wave abnormalities that may indicate cardiac involvement, of which the latter two are most promising and specific. However, prospective studies examining a large number of trials are desirable.

A Patient with Atrioventricular Block and Ventricular Tachycardia: Think Sarcoid!

Cardiac involvement in sarcoidosis is often difficult to diagnose, and most alarmingly can lead to sudden cardiac arrest as its first manifestation. We report the case of a 45-year-old Indian woman with an implanted permanent pacemaker for atrioventricular block, who presented with haemodynamically stable ventricular tachycardia and was found to have impaired left ventricular function. Subsequent investigations established the diagnosis of cardiac sarcoidosis. The patient was treated with prednisolone initially at 40 mg a day for 3 months. Left ventricular function improved over 3 months of treatment and there was no further recurrence of ventricular tachycardia. Screening for cardiac sarcoidosis should be considered in a patient with unexplained atrioventricular block and ventricular tachycardia, particularly if young, even in the absence of clinical findings of extracardiac sarcoidosis. Treatment of the cardiac sarcoidosis could control ventricular tachycardia and improve left ventricular function.

Reproducibility of cardiac magnetic resonance imaging in patients referred for the assessment of cardiac sarcoidosis; implications for clinical practice

Cardiac sarcoidosis (CS) is an increasingly recognized condition, but cardiac magnetic resonance (CMR) image interpretation in these patients may be challenging as findings are often non-specific. The main objective of this study was to investigate the inter-reader agreement for the overall interpretation of CMR for the diagnosis of CS in an experienced reference center and investigate factors that may lead to discrepancies between readers. Consecutive patients undergoing CMR imaging to investigate for CS were included. CMR images were independently reviewed by two readers, blinded to all clinical, imaging and demographic information. The readers classified each scan as "consistent with cardiac sarcoidosis", "not consistent with cardiac sarcoidosis" or "indeterminate". Inter-reader agreement was assessed using κ-statistics. When there was disagreement on the overall interpretation, a third reader reviewed the images. Also, two readers independently commented on the presence of edema, presence of LGE (both ventricles) and quantified the extent of left ventricular LGE. 87 patients (43 women, mean age 54.3 ± 12.2 years) were included in the study. There was agreement regarding the overall interpretation in 72 of 87 (83%) CMR scans. The κ value was 0.64, indicating moderate agreement. There was similar moderate agreement in the interpretation of LGE parameters. In an experienced referral center, we found moderate agreement between readers in the interpretation of CMR in patients with suspected CS. Physicians should be aware of this inter-observer variability in interpretation of CMR studies in patients with suspected CS.

Cardiac Sarcoidosis

Approximately 5% of patients with sarcoidosis will have clinically manifest cardiac involvement presenting with one or more of ventricular arrhythmias, conduction abnormalities, and heart failure. It is estimated that another 20 to 25% of pulmonary/systemic sarcoidosis patients have asymptomatic cardiac involvement (clinically silent disease). Cardiac presentations can be the first (and/or an unrecognized) manifestation of sarcoidosis in a variety of circumstances. Immunosuppression therapy (usually with corticosteroids) has been suggested for the treatment of clinically manifest cardiac sarcoidosis (CS) despite minimal data supporting it. Positron emission tomography imaging is often used to detect active disease and guide immunosuppression. Patients with clinically manifest disease often need device therapy, typically with implantable cardioverter defibrillators (ICDs). The extent of left ventricular dysfunction seems to be the most important predictor of prognosis among patients with clinically manifest CS. In the current era of earlier diagnosis, modern heart failure treatment, and use of ICD therapy, the prognosis from CS is much improved. In a recent Finnish nationwide study, 10-year cardiac survival was 92.5% in 102 patients.

Cardiac Sarcoidosis Causing Ventricular Tachycardia After Myocardial Infarction: A Shocking Diagnosis

Scar-mediated ventricular tachycardia (VT) commonly results from ischemic heart disease. We present a case of recurrent VT, which was initially attributed to ischemic disease; however, the scar location pointed to an alternate pathology. This case demonstrates the utility of multimodality imaging in diagnosing sarcoidosis as a cause of VT. (Level of Difficulty: Intermediate.)

Cardiac Sarcoidosis multi-center randomized controlled trial (CHASM CS- RCT)

Approximately 5% of patients with sarcoidosis have clinically manifest cardiac involvement. Clinical features of Cardiac Sarcoidosis are dependent on the location, extent, and activity of the disease. First line therapy is usually with prednisone and this is recommended based on clinician experience, expert opinion and small observational cohorts. There are no published clinical trials in cardiac sarcoidosis and multiple experts in the field have called for randomized clinical trials to answer important patient care questions. Corticosteroid are associated with multiple adverse effects including hypertension, diabetes, weight gain, osteoporosis, and increased risk of infections. In contrast Methotrexate is generally well tolerated and is increasingly used in other forms of sarcoidosis.

OBJECTIVES

The Cardiac Sarcoidosis Multi-Center Randomized Controlled Trial (CHASM CS-RCT; NCT03593759) is a multicenter randomized controlled trial designed to evaluate the optimal initial treatment strategy for patients with active cardiac sarcoidosis. We hypothesize that (1) a low dose prednisone/methotrexate combination will have non-inferior efficacy to standard dose prednisone and that (2) the low dose prednisone/ methotrexate combination will result in significantly better quality of life than standard dose prednisone, as a result of reduced burden of side effects.

METHODS/DESIGN

Eligible study subjects will have active clinically manifest cardiac sarcoidosis presenting with one or more of the following clinical findings: advanced conduction system disease, significant sinus node dysfunction, non-sustained or sustained ventricular arrhythmia, left ventricular dysfunction or right ventricular dysfunction. Subjects will be randomized in a 1:1 ratio to prednisone 0.5 mg/kg/day for 6 months (maximum dose 30 mg daily) OR to prednisone 20 mg daily for 1 month, then 10 mg daily for 1 month, then 5 mg daily for one month then stop AND methotrexate 15-20 mg once weekly for 6 months. The primary endpoint is summed perfusion rest score on 6-month PET (blinded core-lab review). The summed perfusion rest score is measure of myocardial fibrosis/scar. The design is non-inferiority with a sample size of 97 per group.

DISCUSSION

Given the multiorgan system potential adverse side effects of prednisone, proving noninferiority of an alternate regimen would be sufficient to make the alternative compare favorably to standard dose steroids. This is the first ever clinical trial in cardiac sarcoidosis and thus in addition to the listed goals of the trial, we will also establish a multi-center, multinational cardiac sarcoidosis clinical trials network. Such a collaborative infrastructure will enable a new era of high quality data to guide physicians when treating cardiac sarcoidosis patients.

Long-Term Corticosteroid-Sparing Immunosuppression for Cardiac Sarcoidosis

Background

Long‐term corticosteroid therapy is the standard of care for treatment of cardiac sarcoidosis (CS). The efficacy of long‐term corticosteroid‐sparing immunosuppression in CS is unknown. The goal of this study was to assess the efficacy of methotrexate with or without adalimumab for long‐term disease suppression in CS, and to assess recurrence and adverse event rates after immunosuppression discontinuation.

Methods and Results

Retrospective chart review identified treatment‐naive CS patients at a single academic medical center who received corticosteroid‐sparing maintenance therapy. Demographics, cardiac uptake of 18‐fluorodeoxyglucose, and adverse cardiac events were compared before and during treatment and between those with persistent or interrupted immunosuppression. Twenty‐eight CS patients were followed for a mean 4.1 (SD 1.5) years. Twenty‐five patients received 4 to 8 weeks of high‐dose prednisone (>30 mg/day), followed by taper and maintenance therapy with methotrexate±low‐dose prednisone (low‐dose prednisone, <10 mg/day). Adalimumab was added in 19 patients with persistently active CS or in those with intolerance to methotrexate. Methotrexate±low‐dose prednisone resulted in initial reduction (88%) or elimination (60%) of 18‐fluorodeoxyglucose uptake, and patients receiving adalimumab‐containing regimens experienced improved (84%) or resolved (63%) 18‐fluorodeoxyglucose uptake. Radiologic relapse occurred in 8 of 9 patients after immunosuppression cessation, 4 patients on methotrexate‐containing regimens, and in no patients on adalimumab‐containing regimens.

Conclusions

Corticosteroid‐sparing regimens containing methotrexate with or without adalimumab is an effective maintenance therapy in patients after an initial response is confirmed. Disease recurrence in patients on and off immunosuppression support need for ongoing radiologic surveillance regardless of immunosuppression regimen.

Treatment of cardiac sarcoidosis

PURPOSE OF REVIEW

In sarcoidosis, the appropriate management strategy remains challenging especially because of the lack of confident diagnosis, considerable variability in initial presentation, disease evolution, and outcome. Although asymptomatic patients with limited cardiac involvement have been described to have a benign outcome, cardiac sarcoidosis is associated with high morbidity and mortality and even sudden cardiac death in a significant proportion of patients. Higher morbidity and mortality can be related with both the disease activity and extent of fibrosis.

RECENT FINDINGS

Historical series suggested a 5-year mortality rate of 60% in patients with cardiac sarcoidosis. This has definitely improved with the appropriate use of anti-inflammatory medications as well as heart failure treatment, antiarrhythmic medication and device implantation. Timely recognition and vigorous initial approach is essential in avoiding life-threatening arrhythmias and sudden cardiac death. Advanced imaging modalities have proven to be helpful in the diagnostic approach and guiding treatment decisions. However, there is no optimal screening and risk stratification strategy available and further studies are required to determine, which patients would benefit from the available treatments.

SUMMARY

This review concentrates on the broad principles of management in cardiac sarcoidosis and the efficacy of sarcoidosis-specific medication and cardiac-specific therapies for cardiac dysfunction and rhythm disturbances.

Sensitivity and specificity of chest imaging for sarcoidosis screening in patients with cardiac presentations

Background

Patients with sarcoidosis can present with cardiac symptoms as the first manifestation of disease in any organ. In these patients, the use of chest imaging modalities may serve as an initial screening tool towards the diagnosis of sarcoidosis through identification of pulmonary/mediastinal involvement; however, the use of chest imaging for this purpose has not been well studied. We assessed the utility of different chest imaging modalities for initial screening for cardiac sarcoidosis (CS).

Methods and Results

All patients were investigated with chest x-ray, chest computed tomography (CT) and/or cardiac/thorax magnetic resonance imaging (MRI). We then used the final diagnosis (CS versus no CS) and adjudicated imaging reports (normal versus abnormal) to calculate the sensitivity and specificity of individual and combinations of chest imaging modalities. We identified 44 patients (mean age 54 (±8) years, 35.4% female) and a diagnosis of CS was made in 18/44 patients (41%). The sensitivity and specificity for screening for sarcoidosis were 35% and 85% for chest x-ray, respectively (AUC 0.60; 95%CI 0.42-0.78; p value=0.27); 94% and 86% for chest CT (AUC 0.90; 95%CI 0.80-1.00; p value <0.001); 100% and 50% for cardiac/thorax MRI (AUC 0.75; 95%CI 0.56-0.94; p value=0.04).

Conclusions

During the initial diagnostic workup of patients with suspected CS, chest x-ray was suboptimal as a screening test. In contrast CT chest and cardiac/thorax MRI had excellent sensitivity. Chest CT has the highest specificity among imaging modalities. Cardiac/thorax MRI or chest CT could be used as an initial screening test, depending on local availability.

18F-FDG-PET in Finnish patients with clinical suspicion of cardiac sarcoidosis: Female sex and history of atrioventricular block increase the prevalence of positive PET findings

INTRODUCTION

Fluorodeoxyglucose positron emission tomography (FDG-PET) is a non-invasive imaging modality that has been shown to be a feasible method to demonstrate myocardial inflammation. The aim of this study was to identify the patients suspected of having cardiac sarcoidosis (CS), who are most likely to benefit from PET imaging.

MATERIALS AND METHODS

137 patients suspected of having CS underwent a dedicated cardiac FDG-PET examination at Tampere University Hospital between August 2012 and September 2015. These examinations were retrospectively analyzed.

RESULTS

33 and 12 of the 137 patients had abnormal left and right ventricular (LV and RV) FDG-uptake, respectively. Abnormal LV-uptake and RV-uptake were significantly associated with female sex and a history of advanced AV-block (P < 0.05). Abnormal RV-uptake was also associated with ventricular tachycardia and atrial fibrillation (P < 0.05). 56% of the 27 female patients with a history of AV-block had a pathological PET finding compared to only 6% of the 49 male patients without a history of AV-block. There were 17 female patients with history of both AV-block and ventricular tachycardia, 71% of them had abnormal PET finding.

CONCLUSIONS

Abnormal FDG-PET findings were associated with female sex, AV-block, and arrhythmias in this clinical cohort.

Diagnosis and Therapy of Cardiac Sarcoidosis: A Clinical Perspective

Cardiac sarcoidosis, either as part of a systemic process or in its isolated form, is an important and increasingly recognized disorder. It is associated with high rates of morbidity and mortality, including sudden cardiac death. Early recognition and prompt initiation of treatment is life-saving. A team approach, involving general cardiologists, cardiac electrophysiologists, cardiac imaging specialists and radiologists, is the key to best diagnose and manage this complex disorder. Advanced cardiac imaging with PET and MRI is useful for both diagnosis and managment of therapy. Treatment for this disorder involves immunosuppresant therapy, ICDs, and guideline-directed medical therapy of congestive heart failure.

Sarcoidosis from Head to Toe: What the Radiologist Needs to Know

Sarcoidosis is a multisystem granulomatous disorder characterized by development of noncaseating granulomas in various organs. Although the etiology of this condition is unclear, environmental and genetic factors may be substantial in its pathogenesis. Clinical features are often nonspecific, and imaging is essential to diagnosis. Abnormalities may be seen on chest radiographs in more than 90% of patients with thoracic sarcoidosis. Symmetric hilar and mediastinal adenopathy and pulmonary micronodules in a perilymphatic distribution are characteristic features of sarcoidosis. Irreversible pulmonary fibrosis may be seen in 25% of patients with the disease. Although sarcoidosis commonly involves the lungs, it can affect virtually any organ in the body. Computed tomography (CT), magnetic resonance imaging, and positron emission tomography/CT are useful in the diagnosis of extrapulmonary sarcoidosis, but imaging features may overlap with those of other conditions. Familiarity with the spectrum of multimodality imaging findings of sarcoidosis can help to suggest the diagnosis and guide appropriate management. ^©RSNA, 2018.

Cardiac sarcoidosis - an expert review for the chest physician

Introduction: Sarcoidosis is a multisystem granulomatous disease predominantly affecting the lungs, with increased risk of cardiovascular disease, pulmonary hypertension and cardiac sarcoidosis (CS), the latter due to direct granuloma infiltration. Sarcoidosis is often managed by chest physicians who need to understand the diagnostic pathways and initial management plans for patients with cardiac involvement. Areas covered: The most serious consequence of CS is sudden cardiac death due to ventricular tachyarrhythmias or complete atrioventricular block. Additional complications include atrial arrhythmias and congestive cardiac failure. There are no internationally accepted screening pathways, but a combination of history, clinical examination and ECG detects up to 85% of cases. Newer modalities including signal-averaged ECG and speckle-tracking echocardiography increase identification of patients who require a definitive diagnosis. Early immunosuppression reduces the risk of conduction abnormalities and incidence of supraventricular arrhythmias. Management of ventricular arrhythmias requires antiarrhythmic medications followed by possible catheter ablation and device (ICD) implantation. Expert commentary: Prospective trials are underway to identify the optimum methods for screening, which will guide future international statements on indications for and methods of screening in CS.

Isolated cardiac sarcoidosis: A focused review of an under-recognized entity

There is accumulating evidence for the existence of a phenotype of isolated cardiac sarcoidosis (ICS), or sarcoidosis that only involves the heart. In the absence of biopsy-confirmed cardiac sarcoidosis (CS), existing diagnostic criteria require the presence of extra-cardiac sarcoidosis as an inclusion criterion for the diagnosis of CS. Consequently, in the absence of a positive endomyocardial biopsy, ICS is not diagnosable by current guidelines. Therefore, there is uncertainty regarding the epidemiology, pathobiology, clinical characteristics, prognosis, and optimal treatment of ICS. This review will summarize the available data related to the prevalence and prognosis of ICS and will discuss challenges surrounding the diagnosis and management of this under-recognized entity.

Cardiac manifestations of sarcoidosis: diagnosis and management

Approximately 5% of patients with sarcoidosis will have clinically manifest cardiac involvement presenting with one or more of ventricular arrhythmias, conduction abnormalities, and heart failure. Cardiac presentations can be the first (and/or an unrecognized) manifestation of sarcoidosis in a variety of circumstances. Cardiac symptoms are usually dominant over extra-cardiac as most patients with clinically manifest disease have minimal extra-cardiac disease and up to two-thirds have isolated cardiac sarcoidosis (CS). It is estimated that another 20-25% of pulmonary/systemic sarcoidosis patients have asymptomatic cardiac involvement (clinically silent disease). The extent of left ventricular dysfunction seems to be the most important predictor of prognosis among patients with clinically manifest CS. In addition, the extent of myocardial late gadolinium enhancement is emerging as an important prognostic factor. The literature shows some controversy regarding outcomes for patients with clinically silent CS and larger studies are needed. Immunosuppression therapy (usually with corticosteroids) has been suggested for the treatment of clinically manifest CS despite minimal data supporting it. Fluorodeoxyglucose Positron Emission Tomography imaging is often used to detect active disease and guide immunosuppression. Patients with clinically manifest disease often need device therapy, typically with implantable cardioverter defibrillators.