Diagnosis of isolated cardiac sarcoidosis based on new guidelines

Comparison of prognosis in isolated versus systemic manifestations of cardiac sarcoidosis

BACKGROUND

Isolated cardiac sarcoidosis (iCS) is a poorly understood and under-recognised entity. Previous research has postulated that those with iCS have worsened outcomes compared to those with other manifestations of the disease, however, there have been studies which both support and refute this hypothesis.

PURPOSE OF REVIEW

This review will summarise the literature which focuses on differences in the epidemiology, imaging findings and patient outcome of those with isolated cardiac sarcoidosis (iCS) versus 'systemic' cardiac sarcoidosis (sCS) which is not isolated to the heart.

SUMMARY

Variations in study design make accurate comparison between current papers challenging, and that the factors which indicate poor prognosis in patients with iCS is not yet fully understood. Current literature suggests those with iCS are more likely to be male, have higher numbers of abnormal uptake patterns on cardiac imaging, and may have poorer prognosis than sCS patients. Multi-centre, prospective studies analysing isolated cardiac sarcoidosis across geographical regions are needed to improve our understanding of this phenomenon and ultimately improve patient outcome.

Utility of new FDG-PET/CT guidelines for diagnosing cardiac sarcoidosis in patients with implanted cardiac pacemakers for atrioventricular block

Diagnosing cardiac sarcoidosis (CS), especially in isolated cases, is challenging, particularly due to the limitations of endomyocardial biopsy, leading to potential undiagnosed cases in pacemaker-implanted patients. This study aims to provide real world findings to support new guideline for CS using 18F-fluoro-deoxyglucose positron-emission tomography computed tomography (FDG-PET/CT) which give a definite diagnosis of isolated CS (iCS) without histological findings. We examined consecutive patients with cardiac pacemakers for atrioventricular block (AV-b) attending our outpatient pacemaker clinic. The patients underwent periodical follow-up echocardiography and were divided into two groups according to echocardiographic findings: those with suspected CS and those without suspected CS. Patients suspected of having nonischemic cardiomyopathy underwent FDG-PET/CT for CS diagnosis. We investigated the utility of the new guideline for CS using FDG-PET/CT. Among the 272 patients enrolled, 97 patients were implanted with cardiac pacemakers for AV-b. Twenty-two patients were suspected of having CS during a median observation period of 5.4 years after pacemaker implantation. Of these, one did not consent, and nine of 21 cases (43%) were diagnosed with definite CS according to the new guidelines. Five of these nine patients were diagnosed with iCS using FDG-PET/CT. The number of patients diagnosed with definite CS using the new guidelines tended to be approximately 2.3 times that of the conventional criteria (p = 0.074). Three of the nine patients underwent steroid treatment. The composite outcome, comprising all-cause death, heart failure hospitalization, and a substantial reduction in left ventricular ejection fraction, were significantly lower in patients receiving steroid treatment compared to those without steroid treatment (p = 0.048). The utilization of FDG-PET/CT in accordance with the new guidelines facilitates the diagnosis of CS, including iCS, resulting in approximately 2.3 times as many diagnoses of CS compared to the conventional criteria. This guideline has the potential to support the early identification of iCS and may contribute to enhancing patient clinical outcomes.

Cardiac Sarcoidosis

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

[Régurgitation mitrale sévère due à la sarcoïdose cardiaque : une présentation clinique inhabituelle ; une étude de cas et des recherches antérieures]

Sarcoidosis is a granulomatous inflammatory disease that may involve multiple organ systems, including the heart. Cardiac manifestations are not rare and include atrial and ventricular arrhythmias, conduction abnormalities, congestive heart failure, valvular dysfunction, pericarditis, and sudden death. Although, cardiac sarcoidosis (CS) remains a diagnostic and therapeutic challenge. This article describes a case of a patient with a history of pulmonary sarcoidosis who presented with congestive heart failure, on the basis of severe mitral regurgitation secondary to cardiac infiltration and summarizes the published evidence regarding CS and mitral regurgitation.

Clinical characteristics and prognosis of patients with isolated cardiac sarcoidosis: Insights from the ILLUMINATE-CS study

AIM

Data on the clinical features and prognosis of patients with isolated cardiac sarcoidosis (iCS) are limited. This study evaluated the clinical characteristics and prognostic impact of iCS.

METHODS AND RESULTS

This was a secondary analysis of the ILLUMINATE-CS study, a multicentre, retrospective registry investigating the clinical characteristics and prognosis of cardiac sarcoidosis. iCS was diagnosed according to the 2016 Japanese Circulation Society (JCS) guidelines. Clinical characteristics and prognosis were compared between patients with iCS and systemic cardiac sarcoidosis (sCS). The primary outcome was a combined endpoint of all-cause death, hospitalization for heart failure, or fatal ventricular arrhythmia events. Among 475 patients with CS (mean age, 62.0 ± 10.9 years; female ratio, 59%) diagnosed by the JCS guidelines, 119 (25.1%) were diagnosed with iCS. Patients with iCS had a higher prevalence of a history of atrial fibrillation or hospitalization for heart failure, or lower left ventricular ejection fraction than those with sCS. During a median follow-up of 42.3 (interquartile range, 22.8-72.5) months, 141 primary outcomes (29.7%) occurred. Cox proportional hazard analysis revealed that iCS was a significant risk factor for the primary outcome in the unadjusted model (hazard ratio [HR] 1.62; 95% confidence interval [CI] 1.12-2.34; p = 0.011). However, this association was not retained after adjustment for other covariates (adjusted HR 1.27; 95% CI 0.86-1.88; p = 0.226).

CONCLUSIONS

Patients with iCS had more impaired cardiovascular function at the time of diagnosis than those with sCS. However, iCS was not independently associated with poor prognosis after adjustment for prognostic factors.

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.

Long-Term Outcomes of Cardiac Sarcoid: Prognostic Implications of Isolated Cardiac Involvement and Impact of Diagnostic Delays

Background Isolated cardiac sarcoid (iCS) is reported to have more severe clinical presentation and greater risk of adverse events compared with cardiac sarcoid (CS) with extracardiac involvement (nonisolated CS). Delays in diagnosing specific organ involvement may play a role in these described differences. Methods and Results A retrospective observational study of patients with CS over a 20-year period was conducted. Objective evidence of organ involvement and time of onset based on consensus criteria were identified. CS was confirmed by histology in all patients from myocardium only (iCS) or extracardiac tissue (nonisolated CS). The primary end point was a composite of mortality, orthotopic heart transplant, and durable left ventricular assist device implantation. CS was isolated in 9 of 50 patients (18%). Among baseline characteristics, iCS and nonisolated CS differed significantly only in the frequency of sustained ventricular tachycardia at presentation (78% versus 37%; P=0.03) and delay in CS diagnosis >6 months (67% versus 5%; P<0.01). A nonsignificant trend toward lower left ventricular ejection fraction and more frequent heart failure in iCS was observed. Over a median follow-up of 9.7 years (95% CI, 6.8-10.8), 18 patients reached the primary end point (13 deaths, 2 orthotopic heart transplants, and 3 durable left ventricular assist device implantations). The 1-, 5-, and 10-year event-free survival rates were 96% (95% CI, 85%-99%), 79% (95% CI, 64%-88%), and 58% (95% CI, 40%-73%), respectively, without differences between groups. There were no significant predictors of the primary end point, including delayed CS diagnosis. Conclusions Long-term outcomes were similar between iCS and nonisolated CS in patients with histologically documented sarcoid. Diagnostic delays may contribute to differences in the dominant clinical presentation, despite similar outcomes.

Update on cardiac sarcoidosis

Cardiac sarcoidosis is an inflammatory myocardial disease of unknown etiology. It is characterized by the deposition of non-caseating granulomas that may involve any part of the heart. Cardiac sarcoidosis is often under-diagnosed or recognized partly due to the heterogeneous clinical presentation of the disease. The three most frequent clinical manifestations of cardiac sarcoidosis are atrioventricular block, ventricular arrhythmias, and heart failure. A definitive diagnosis of cardiac sarcoidosis can be made with histology findings from an endomyocardial biopsy. However, the diagnosis in the majority of cases is based on findings from the clinical presentation and advanced imaging due to the low sensitivity of endomyocardial biopsy. The Heart Rhythm Society (HRS) 2014 expert consensus statement and the Japanese Ministry of Health and Welfare criteria are the two most commonly used diagnostic criteria sets. This review article summarizes the available evidence on cardiac sarcoidosis, focusing on the diagnostic criteria and stepwise approach to its management.

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.

Is Imaging Bacteria with PET a Realistic Option or an Illusion?

The application of [¹⁸F]-fluorodeoxyglucose ([¹⁸F]FDG) as a radiotracer to detect sites of inflammation (either due to bacterial infection or primary inflammation) has led to exploring the role of PET in visualizing bacteria directly at sites of infection. However, the results from such efforts are controversial and inconclusive so far. We aimed to assess the limitations of PET as an effective modality in the diagnosis of bacterial infections. Inflammation due to bacterial infections can be visualized by using [¹⁸F]FDG-PET. However, the non-specificity of [¹⁸F]FDG makes it undesirable to visualize bacteria as the underlying cause of inflammation. Hence, more specific radiotracers that possibly bind to or accumulate in bacteria-specific receptors or enzymes are being explored. Several radiotracers, including 2-deoxy-2-[¹⁸F]fluorosorbitol ([¹⁸F]FDS), 6-[¹⁸F]-fluoromaltose, [¹¹C]para-aminobenzoic acid ([¹¹C]PABA), radiolabeled trimethoprim (¹¹C-TMP) and its analog fluoropropyl-trimethoprim (¹⁸F-FPTMP), other radiolabeled sugars, and antimicrobial drugs have been used to image microorganisms. Unfortunately, no progress has been made in translating the results to routine human use; feasibility and other factors have constrained their success in clinical settings. In the current article, we discuss the limitations of direct bacterial visualization with PET tracers, but emphasize the important role of [¹⁸F]FDG-PET as the only option for detecting evidence of infection.

Pathophysiological Gaps, Diagnostic Challenges, and Uncertainties in Cardiac Sarcoidosis

Cardiac sarcoidosis can mimic any cardiomyopathy in different stages. Noncaseating granulomatous inflammation can be missed, because of the nonhomogeneous distribution in the heart. The current diagnostic criteria show discrepancies and are partly nonspecific and insensitive. Besides the diagnostic pitfalls, there are controversies in the understanding of the causes, genetic and environmental background, and the natural evolution of the disease. Here, we review the current pathophysiological aspects and gaps that are relevant for future cardiac sarcoidosis diagnostics and research.

Cardiac Sarcoidosis With Elevated Cardiac Troponin Mimicking Acute Myocardial Ischemia: A Case Report

Cardiac sarcoidosis (CS) is a disease entity with variable presentation causing significant morbidity and mortality. Concurrent signs of myocardial injury as evidenced by troponin elevation add to the complexity of an already challenging diagnosis. We present an unusual case of CS with elevated troponin I mimicking an acute ischemic cardiac event. A 48-year-old female presented with a two-month history of presyncope.  Electrocardiogram showed a bifascicular block with concomitant significant troponin I elevation. Two-dimensional echocardiography showed new-onset left ventricular systolic dysfunction with an ejection fraction of 40-45%. A heparin drip was initiated for possible non-ST-elevation myocardial infarction. Coronary angiography showed no evidence of epicardial coronary artery disease but did show an anomalous right coronary artery; however, CT angiography did not reveal any significant stenosis. Further, the telemetry monitor captured intermittent complete atrioventricular blocks. Due to concerns for an infiltrative cardiac disease, a cardiac magnetic resonance was done showing findings consistent with possible CS.  CT scan of the chest showed no radiographic evidence of pulmonary sarcoidosis. Fluorodeoxyglucose-positron emission tomography scan showed findings of active inflammation in the myocardium consistent with possible CS. The patient was treated for clinical CS with systemic corticosteroids and methotrexate. Follow-up six weeks later showed clinical improvement of symptoms. Our clinical case encompasses the unique variable presentation of CS including cardiac conduction abnormalities and left ventricular systolic dysfunction. Concomitant troponin I elevation can mimic myocardial ischemia, making the diagnosis more challenging. Treatment strategies aim to mitigate the long-term effects of CS on the heart; however, there is a paucity of data for appropriate pharmacological regimens.

FDG PET/CT Imaging of Sarcoidosis

Sarcoidosis is a multisystemic granulomatous disease of unknown etiology. The diagnostic can be made by histological identification of non-caseous granuloma or by a combination of clinical criteria. Active inflammatory granuloma can lead to fibrotic damage. Although 50% of cases resolve spontaneously, systemic treatments are often necessary to decrease symptoms and avoid permanent organ dysfunction, notably in cardiac sarcoidosis. The course of the disease can be punctuated by exacerbations and relapses and the prognostic depends mainly on affected sites and patient management. FDG-PET/CT along with newer FDG-PET/MR have emerged as key imaging modalities in sarcoidosis, namely for certain diagnostic purposes, staging and biopsy guiding. By identifying with a high sensitivity inflammatory active granuloma, FDG hybrid imaging is a main prognostic tool and therapeutic ally in sarcoidosis. This review aims to highlight the actual critical roles of hybrid PET imaging in sarcoidosis and display a brief perspective for the future which appears to include other radiotracers and artificial intelligence applications.

Clinical features and prognosis of isolated cardiac sarcoidosis diagnosed using new guidelines with dedicated FDG PET/CT

BACKGROUND

Diagnostic guidelines for isolated cardiac sarcoidosis (iCS) were first proposed in 2016, but there are few reports on the imaging and prognosis of iCS. This study aimed to evaluate the use of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging in predicting iCS prognosis.

METHODS AND RESULTS

We retrospectively reviewed the clinical and imaging data of 306 consecutive patients with suspected CS who underwent FDG PET/CT with a dedicated preparation protocol and included 82 patients (55 with systemic sarcoidosis including cardiac involvement [sCS], 27 with iCS) in the study. We compared the FDG PET/CT findings between the two groups. We examined the relationship between the CS type and the rate of adverse cardiac events. The iCS group had a significantly lower target-to-background ratio than the sCS group (P = 0.0010). The event-free survival rate was significantly lower in the iCS group than the sCS group (log-rank test, P < 0.0001). iCS was identified as an independent prognostic factor for adverse events (hazard ratio 3.82, P = 0.0059).

CONCLUSION

iCS was an independent prognostic factor for adverse cardiac events in patients with CS. The clinical diagnosis of iCS based on FDG PET/CT and new guidelines may be important.

Cardiac Sarcoidosis: Current Approaches to Diagnosis and Management

PURPOSE OF REVIEW

Cardiac sarcoidosis (CS) is an important cause of non-ischemic cardiomyopathy and has specific diagnostic and therapeutic considerations. With advances in imaging techniques and treatment approaches, the approach to monitoring disease progression and management of CS continues to evolve. The purpose of this review is to highlight advances in CS diagnosis and treatment and present a center's multidisciplinary approach to CS care.

RECENT FINDINGS

In this review, we highlight advances in granuloma biology along with contemporary diagnostic approaches. Moreover, we expand on current targets of immunosuppression focused on granuloma biology and concurrent advances in the cardiovascular care of CS in light of recent guideline recommendations. Here, we review advances in the understanding of the sarcoidosis granuloma along with contemporary diagnostic and therapeutic considerations for CS. Additionally, we highlight knowledge gaps and areas for future research in CS treatment.

State-of-the-Art Treatments for Sarcoidosis

Sarcoidosis is a heterogeneous disease with various treatment indications. Although it affects mainly the lungs, sarcoidosis can affect every organ, especially when the disease course is chronic and protracted. Regular patient follow-up is recommended for early recognition of active, ongoing organ-specific granulomatous inflammation to avoid progression to irreversible fibrosis. In this review, we elaborate on treatment indications and various anti-sarcoidosis regimens proven useful in clinical trials. We also review specialized treatment of specific disease manifestations, with a focus on cardiac sarcoidosis. We also report on treatment for special conditions such as fatigue and small fiber neuropathy. Treatment for sarcoidosis is an emerging landscape, with new data complementing the existing knowledge.

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.

The characteristics of Japanese guidelines on diagnosis and treatment of cardiac sarcoidosis compared with the previous guidelines

Sarcoidosis in Japanese sarcoidosis is characterized by a high prevalence of cardiac involvement. In this regard, cardiac sarcoidosis (CS) continues to be an important focus of study among physicians caring for sarcoidosis in Japan. The Japanese Ministry of Health, Labor and Welfare (MHLW) and Japan Society of Sarcoidosis and other Granulomatous Disorders (JSSOG) have published clinical guidelines aiming to assist clinical practices. Recently, the Japanese Circulation Society (JCS) has published new clinical guidelines for the diagnosis and treatment of CS that contain several new insights compared to previously published guidelines in Japan and other countries.

Clinical outcomes of patients with isolated cardiac sarcoidosis confirmed by clinical diagnostic criteria

BACKGROUND

Although isolated cardiac sarcoidosis (CS) is not uncommon, little is known about the prognosis. We aimed to clarify clinical features and clinical outcomes in patients with isolated CS.

METHODS

Two-hundred eighty-six patients with suspected CS were enrolled. Systemic CS (SCS) was diagnosed by histological or clinical confirmation of sarcoidosis according to the guidelines. Isolated CS was diagnosed by histological or clinical confirmation in the heart alone. The endpoint was cardiac death, hospitalization for heart failure, or fatal ventricular arrhythmia.

RESULTS

Twenty-one patients were diagnosed with isolated CS, and 63 were diagnosed with SCS. The frequencies of diagnostic criteria, such as high-grade atrioventricular block or fatal ventricular arrhythmia, basal thinning of the ventricular septum, left ventricular contractile dysfunction, positive myocardial uptake of gallium-67 citrate scintigraphy or fluorine-18 fluorodeoxyglucose positron emission tomography, and delayed contrast enhancement of cardiac magnetic resonance, were higher or equivalent in patients with isolated CS, compared to those with SCS. Over a median follow-up of 31 months (range: 1-175 months), cardiac death, hospitalization for heart failure, or fatal ventricular arrhythmia occurred in 14 (67%) patients with isolated CS, 24 (38%) patients with SCS, and 63 (31%) patients without CS. The rate of cardiac events was higher in patients with isolated CS (log-rank test, p = 0.01). Cox proportional hazard analysis showed that isolated CS, age, and New York Heart Association functional class were independently associated with cardiac events.

CONCLUSIONS

Patients with isolated CS have clinical features compatible with SCS, and have cardiac events at a higher rate.

Prognosis and Outcomes of Clinically Diagnosed Cardiac Sarcoidosis Without Positive Endomyocardial Biopsy Findings

Background

Diagnosis of cardiac sarcoidosis (CS) is sometimes difficult due to a low positive rate of epithelioid granulomas by endomyocardial biopsy (EMB). Accordingly, Japanese guidelines can allow the CS diagnosis using clinical data alone without EMB results (clinical CS) since 2006. However, little is known about prognosis and outcome of clinical CS.

Objectives

Purpose of this study was to analyze the prognosis, outcomes, and response to corticosteroid of clinical CS using large-scale cohort survey.

Methods

Overall, 422 CS patients (mean age 60 ± 13 years, 68% female, median follow-up period of 5 years), including 345 clinical CS and 77 EMB-positive patients, histologically diagnosed CS (histological CS) by Japanese guidelines, were enrolled and examined.

Results

Clinical profile (age, sex, initial cardiac arrhythmias, and abnormal uptake of gallium-67 scintigraphy or ¹⁸F-fluorodeoxyglucose positron emission tomography in heart) was similar in both groups. Although clinical CS had better prognosis (P = 0.018) and outcome (all-cause death, appropriate defibrillator therapy, and heart transplantation; P = 0.008), multivariate Cox hazard analysis revealed that left ventricular ejection fraction (LVEF) and sustained ventricular tachycardia history were independently associated with outcome (P < 0.001 and P = 0.002, respectively), but not with the diagnosed CS category. Moreover, similar LVEF recovery after corticosteroid was observed in both groups with low LVEF (≤35%) at the 1-year follow-up period (P < 0.001).

Conclusions

In clinical CS according to the Japanese guideline, prophylactic implantable-cardioverter-defibrillator and immunosuppressive therapy are important in patients with low LVEF or ventricular tachycardia history, similar to histological CS.

Isolated Cardiac Sarcoidosis with High-Grade Heart Block: Utilization of New Diagnostic Guidelines

Cardiac sarcoidosis can present with heart failure and conduction disease. This is a case of a 58-year-old male who presented for dyspnea, edema, and varying degrees of heart block. Using new updated diagnostic guidelines and multimodal cardiac imaging, he was diagnosed with isolated cardiac sarcoidosis.

The Role of Multimodality Imaging in Cardiac Sarcoidosis

The etiology and the progression of sarcoidosis remain unknown. However, cardiac sarcoidosis (CS) is significantly associated with a poor prognosis due to the associated congestive heart failure, arrhythmias (such as an advanced atrioventricular block), and ventricular tachyarrhythmia. Novel imaging modalities are now available to detect CS lesions secondary to active inflammation, granuloma formation, and fibrotic changes. ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) and cardiac magnetic resonance imaging (CMR) play essential roles in diagnosing and monitoring patients with confirmed or suspected CS. The following focused review will highlight the emerging role of non-invasive cardiac imaging techniques, including FDG PET/CT and CMR.

Manifestations and Outcome of Cardiac Sarcoidosis and Idiopathic Giant Cell Myocarditis by 25-Year Nationwide Cohorts

Background Cardiac sarcoidosis (CS) and giant cell myocarditis (GCM) share many histopathologic and clinical features. Whether they are parts of a one-disease continuum has been discussed. Methods and Results We compared medical record data of 351 CS and 28 GCM cases diagnosed in Finland since the late 1980s and followed until February 2018 for a composite end point of cardiac death, aborted sudden death, and heart transplantation. Heart failure was the presenting manifestation in 50% versus 15% (P<0.001), and high-grade atrioventricular block in 21% versus 43% (P=0.044), of GCM and CS, respectively. At presentation, left ventricular ejection fraction was ≤50% in 81% of cases of GCM versus in 48% of CS (P=0.004). The median (interquartile range) of plasma NT-proBNP (N-terminal pro-B-type natriuretic peptide) was 5273 (2782-11309) ng/L on admission in GCM versus 859 (290-1950) ng/L in CS (P<0.001), and cardiac troponin T exceeded 50 ng/L in 17 of 19 cases of GCM versus in 48 of 239 cases of CS (P<0.001). The 5-year estimate of event-free survival was 77% (95% CI, 72%-82%) in CS versus 27% (95% CI, 10%-45%) in GCM (P<0.001). By Cox regression analysis, GCM predicted cardiac events with a hazard ratio of 5.16 (95% CI, 2.82-9.45), which, however, decreased to 1.58 (95% CI, 0.71-3.52) after inclusion of markers of myocardial injury and dysfunction in the model. Conclusions GCM differs from CS in presenting with more extensive myocardial injury and having worse long-term outcome. Yet the key determinant of prognosis appears to be the extent of myocardial injury rather than the histopathologic diagnosis.

The Importance of Multimodality Imaging in the Diagnosis and Management of Patients with Infiltrative Cardiomyopathies: An Update

Infiltrative cardiomyopathies (ICMs) comprise a broad spectrum of inherited and acquired conditions (mainly amyloidosis, sarcoidosis, and hemochromatosis), where the progressive buildup of abnormal substances within the myocardium results in left ventricular hypertrophy and manifests as restrictive physiology. Noninvasive multimodality imaging has gradually eliminated endomyocardial biopsy from the diagnostic workup of infiltrative cardiac deposition diseases. However, even with modern imaging techniques’ widespread availability, these pathologies persist in being largely under- or misdiagnosed. Considering the advent of novel, revolutionary pharmacotherapies for cardiac amyloidosis, the archetypal example of ICM, a standardized diagnostic approach is warranted. Therefore, this review aims to emphasize the importance of contemporary cardiac imaging in identifying specific ICM and improving outcomes via the prompt initiation of a targeted treatment.

Diagnosis of isolated cardiac sarcoidosis based on new guidelines

Aims

In the updated guidelines for cardiac sarcoidosis (CS) proposed by the Japanese Circulation Society (JCS), the definition of isolated CS (iCS) was established for the first time. This prompted us to examine the characteristics of patients with CS including iCS according to them by reviewing patients undergoing ¹⁸F‐fluoro‐2‐deoxyglucose positron‐emission tomography/computerized tomography (FDG‐PET/CT), compared with those with CS determined by the conventional international criteria.

Methods and results

From 2013 to 2019, 94 patients (61 ± 15 years, 50 female patients) with suspected CS underwent whole‐body and cardiac FDG‐PET/CT scanning. In contrast to 22 patients with CS based on the international criteria, 34 [27 with systemic sarcoidosis including cardiac involvement (sCS) and 7 with definitive iCS] were diagnosed with CS according to the new JCS guidelines (P = 0.012), and 60 were not (4 suspected iCS, 13 systematic sarcoidosis without cardiac involvement, and 43 no sarcoidosis). In addition to 26 of 34 patients with CS, corticosteroids were also started in 6 of 60 without CS according to clinical need.

Conclusions

Diagnostic yield with the new JCS guidelines was higher, with approximately 1.5‐fold of the patients diagnosed with CS compared with the previous international criteria and definitive iCS accounting for approximately 20% of the whole CS cohort. In addition to 75% of the patients with sCS or definitive iCS in the updated guidelines, 10% in whom CS was not documented were also started on corticosteroids for clinical indications such as reduced cardiac function or arrhythmia.