Diagnosis Of Cardiac Sarcoidosis Research Articles

Role of Multimodality Imaging in Cardiac Sarcoidosis: A Retrospective Single-Center Experience

Background/Objectives: Cardiac sarcoidosis (CS) is a rare entity characterized by granulomatous infiltration of the myocardium, which can lead to myocardial fibrosis, conduction abnormalities, and the development of heart failure, thereby elevating the risk of sudden cardiac death (SCD). While endomyocardial biopsy (EMBx) is regarded as the gold standard for diagnosis, its low sensitivity and inherent procedural risks may limit its practical application. Methods: This study retrospectively explored the role of advanced imaging modalities, specifically cardiovascular magnetic resonance imaging (CMR) and fluorodeoxyglucose positron emission tomography (FDG-PET), in the diagnosis and management of CS within a single center. In this retrospective study, we aimed to assess the utility of advanced imaging modalities in the clinical diagnosis of CS and the monitoring of treatment. Results: A total of 92 patients were identified as having cardiac sarcoidosis, with males constituting 66.3% of the sample and a mean age of 62 years (±11.9). Among these patients, 80 (87%) underwent FDG-PET. Here, the basal inferolateral segment was the most frequently observed segment of the heart with FDG uptake. A total of 77 patients (84%) underwent CMR, with 51 demonstrating late gadolinium enhancement (LGE). The basal inferolateral segment exhibited the highest frequency of LGE (26%). Logistic regression analysis indicated that patients presenting with a combination of LGE, FDG uptake on PET, and a “mismatch pattern” faced a two-fold increase in the risk of experiencing major adverse cardiac events (odds ratio = 2.311, p = 0.077). Conclusions: This study underscores the importance of multimodality imaging as a non-invasive alternative for CS diagnosis and management, reducing reliance on EMBx.

Hospitalizations and cardiac sarcoidosis: insights into presentation and diagnosis from the nationwide readmission database.

Cardiac sarcoidosis (CS) is an increasingly recognized cause of cardiac disease. Because the clinical presentation of CS is non-specific, the diagnosis is often delayed. Early detection is essential to initiate treatments that reduce the risk of heart failure (HF) and arrhythmic death. We therefore aimed to describe the features of CS hospitalizations during which the initial diagnosis of CS is made. We performed a retrospective analysis of hospitalizations from 2016 to 2019 in the Nationwide Readmission Database (NRD). Hospitalizations with a primary diagnosis suggestive of CS (HF/cardiomyopathy, cardiac arrest, arrhythmias, or heart block) were categorized into cases with and without CS as a secondary diagnosis (CS+ and CS-, respectively). One-to-one propensity score matching (PSM) was performed. The CS+ cohort comprised 1,146 hospitalizations and the CS- cohort 3,250,696 hospitalizations. The CS+ cohort included patients who were younger and more often male. PSM resulted in highly matched cohorts (absolute standardized mean difference <0.1). Primary diagnoses of ventricular arrhythmias (VA) or heart block were more frequent in matched CS+ hospitalizations, whereas primary diagnosis of HF/cardiomyopathy was more frequent in matched CS- hospitalizations. The matched CS+ group exhibited higher rates of in-hospital procedures and longer length of stay. In-hospital mortality and 30-day readmission were similar between matched cohorts. These findings highlight increased rates of CS in younger males with primary diagnoses of VA and heart block, and increased use of diagnostic and therapeutic interventions such as pacemaker and left ventricular assist device implantation, and could aid clinicians in more timely diagnosis and treatment of CS.

A Pharmacist Medication Titration Program for Patients with Cardiac Sarcoidosis and Systolic Heart Failure: A Retrospective Cohort Study

Background A multidisciplinary approach improves guideline‐directed medical therapy (GDMT) in systolic heart failure (HF), but its efficacy in patients with HF due to cardiac sarcoidosis (CS) is unreported. Methods and Results In a retrospective cohort study, we reviewed 848 patients from our institutional CS clinics, identifying those with a CS diagnosis, HF (LVEF &lt; 50%) at index evaluation, and echocardiograms within 90 days and 11‐36 months. Patients were stratified by participation in a pharmacist‐led medication therapy management (MTM) program for GDMT optimization (MTM vs non‐MTM [NMTM]) without randomization. Demographics, LVEF, GDMT (quantified by Kansas City Medical Optimization [KCMO] score), and immunosuppressive therapy were assessed. Primary outcomes included changes in KCMO score, LVEF, and cardiovascular event‐free survival (unplanned HF hospitalization, LVAD/heart transplant, or death). The final cohort included 111 patients (median age 57 years, 34% female, 64% NYHA Class I‐II); 43 (39%) were MTM and 68 (61%) were NMTM. Mean KCMO score was similar at index evaluation (MTM: 23.2; NMTM: 29.6, p=0.83). At follow‐up (median 16 months), the KCMO score increased significantly in both groups (MTM: 23.2 to 74.8, p&lt;0.001; NMTM: 29.6 to 58.7, p&lt;0.001), but was higher in MTM (p=0.001). Mean LVEF trended towards higher values in MTM (44.4% vs 40.0%, p=0.05). The primary clinical outcome occurred in 1 MTM (2.3%) and 16 NMTM (23.5%) patients, with higher risk in NMTM (HR 11.97 [95%CI 1.58 ‐ 90.54], p=0.002). Conclusions In this retrospective cohort study, a pharmacist‐led MTM program was associated with favorable GDMT optimization and lower risk of adverse cardiovascular outcomes in CS patients with HF.

Abstract 4123956: Upgrade to Implantable Cardioverter-Defibrillator in Patients Diagnosed with Cardiac Sarcoidosis after Permanent Pacemaker Implantation for High-Grade Atrioventricular Block

Introduction: Unexplained high-grade AV block (AVB) in patients age &lt;65 years is among the salient features of cardiac sarcoidosis (CS). Guidelines recommend that CS patients with high-grade AVB should receive an implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy-defibrillator (CRT-D) rather than a permanent pacemaker (PPM). However, in clinical practice, CS may be recognized after PPM implantation for high-grade AVB. Aims: To evaluate the characteristics and outcomes of patients diagnosed with CS after PPM implantation for high-grade AVB and assess the decision-making and rationale for upgrade to ICD/CRT-D. Methods: Retrospective review of the Mayo Clinic Sarcoid Registry (n=848) was performed to identify all patients for which a PPM was implanted for high-grade AVB prior to the diagnosis of CS. Baseline clinical and imaging characteristics were collected during index evaluation at our institution. Decision-making for ICD upgrade, lead management strategy, immunosuppression initiation, and outcomes were assessed. Results: Overall, 29 of 848 (3.4%) of CS patients (62% probable/definite CS; 77% male; median (IQR) age 56 (48-61) years; and median (IQR) LVEF 58% (50-62) received a PPM for high-grade AVB prior to a CS diagnosis. Median (IQR) interval between PPM implant and index evaluation was 10 (3-23) months. Eight of 29 patients underwent upgrade to ICD (n=4) or CRT-D (n=4). Among them, the pacing lead was extracted in 4. All patients were upgraded for primary prevention of sudden cardiac death (SCD), with 3 of them also having LVEF&lt;50% requiring upgrade to CRT-D. Twenty-two (79%) patients in the total cohort were treated with immunosuppression. During median (IQR) follow-up 37 months (11-74), 1 patient in the upgrade group had sustained VT appropriately treated with anti-tachycardia pacing. No events were documented among patients in the non-upgrade group. At last follow-up, 6 (75%) patients in the upgrade group and 12 (57%) in the non-upgrade group were pacemaker dependent. Median LVEF change was 0% in patients who underwent upgrade to CRT-D and –0.2% in those who underwent upgrade to ICD or no upgrade. Conclusions: In this cohort of patients diagnosed with CS several months after a PPM had been implanted for high-grade AVB, incident VT/VF was infrequent with contemporary CS management. In the absence of other SCD risk factors, CS patients who received a PPM for high-grade AVB prior to their CS diagnosis may not require ICD upgrade.

Abstract 4136412: Quantitative Cardiac Magnetic Resonance Standardized Signal Intensity Comparison in Dilated Cardiomyopathy versus Cardiac Sarcoidosis

Introduction/Background: Dilated cardiomyopathy (DCM) and cardiac sarcoidosis (CS) manifest unique late gadolinium enhancement (LGE) patterns on cardiac magnetic resonance (CMR), indicative of differing distributions of myocardial scar tissue. Nevertheless, these LGE patterns lack specificity, leading to significant overlap between the two conditions. Goals/Aims: This study seeks to introduce a novel quantitative method employing z-score analysis of LGE-CMR signal intensity to objectively evaluate and compare the spatial distribution of LGE intensity between DCM and CS. Methods/Approach: The retrospective cohort included 22 NICM patients (13 DCM, 9 CS) that underwent pre-procedural CMR prior to ventricular tachycardia (VT) ablation between November 2018 to May 2023. LGE images were delineated into sub-endocardial, mid-myocardial, and sub-epicardial layers, categorized into anterior, lateral, inferior, and septal walls based on the AHA 17 segment model for LV myocardial segmentation. CMR signal intensities were standardized as z-scores: z = (x−μ)/σ, where x is the MRI signal intensity for a specific myocardial segment and layer, and μ and σ are the mean and standard deviation across all myocardial segments and layers of the LV, to characterize regional intensity variations. Results/Data: Compared to patients with DCM, those with CS exhibited significantly higher CMR signal intensity z-scores in the septum (β=0.32, p=0.009), particularly in the endocardial third of the right ventricular side (β=0.56, p=0.001). A z-score greater than 0.40 in this area was associated with a CS diagnosis, with an area under the ROC curve of 0.692 in 5-fold cross-validation. Conclusions: Patients with CS exhibit higher affinity for contrast in the septum, particularly on the RV endocardium. Standardized analysis of CMR signal intensities provides a novel, quantitative method for distinguishing CS from DCM, with the former exhibiting higher CMR signal intensity z-scores in the septum.

Abstract 4137113: The Effectiveness of Cardiac Resynchronization Therapy in Patients with Cardiac Sarcoidosis: A Retrospective Analysis

Background: Cardiac sarcoidosis (CS) manifests in a wide range of clinical presentations, including conduction system abnormalities, ventricular arrhythmias, and systolic heart failure. Although cardiac resynchronization therapy (CRT) has shown efficacy in treating select nonischemic cardiomyopathy patients, its specific impact on CS patients remains less explored. This study aimed to evaluate the outcomes of CRT therapy in CS patients, focusing on implantable cardioverter defibrillator (ICD) therapies, heart failure (HF) hospitalizations and mortality. Methods: We retrospectively reviewed all patients with a clinical or histological diagnosis of CS who underwent device implantation (ICD or Permanent Pacemaker (PPM)) with or without CRT therapy at Johns Hopkins Hospital between 2004 and 2024. Baseline characteristics and echocardiographic parameters were assessed. Heart failure hospitalizations, the frequency of ATP (Anti-Tachycardia Pacing) or ICD shocks, and all-cause mortality were also evaluated as the outcomes. Results: The study included 212 patients (40.1% female, average age 52.8 ± 11.1 years). Eighty-five patients underwent CRT implantation (82 CRT-D and 3 CRT-P), whereas the rest received either an ICD or a PPM without CRT therapy. Most CRT devices (58.82%) were upgrades from an initial PPM or ICD. Over a follow-up of 6.15 ± 4.43 years, 27 (12.74%) patients were hospitalized for heart failure (HF), 86 (40.56%) experienced ATP or ICD shocks, and 17 (8.02%) died. The composite outcome was observed in 103 patients (48.5%), with no significant differences between CRT and non-CRT groups ( P = .51). Survival analysis indicated significantly reduced freedom from HF hospitalizations in the CRT group compared to non-CRT group ( P = .01). However, ATP/ICD shocks did not have a significant difference. CRT recipients showed an improvement in left ventricular ejection fraction (LVEF) from 35.3 ± 12.6% to 38.9 ± 13.6% at 6 months ( P = .01). Non-recipients showed no significant change in LVEF ( P = .43). Conclusions: Over an average six-year follow-up period, CRT upgrade does not appear to affect ATP/ICD shock and mortality in CS patients, although it is associated with significantly higher rates of heart failure (HF) hospitalizations compared to CS patients with an ICD or PPM alone. These findings underscore the complex response of CS patients to CRT, highlighting the need for further research to optimize treatment strategies within this subgroup.

The role of 18fluorine-fluorodeoxyglucose positron emission tomography in the diagnosis, follow-up, and regulation of treatment in patients with cardiac sarcoidosis.

Abstract Background Cardiac sarcoidosis (CS) is a potentially fatal disease, commonly presenting with arrhythmias, heart failure, or sudden death. Diagnostic challenges persist, particularly due to limited sensitivity of endomyocardial biopsy (20-25%). Alternative diagnostic approaches, such as criteria-based diagnosis, have emerged. 18fluorine-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) has gained prominence in diagnosing CS, monitoring treatment, and serving as a follow-up tool, although its precise role and efficacy remain unclear. Purpose This retrospective cohort study sought to characterize patients with CS who underwent at least one 118F-FDG-PET scan. Primary objectives were to explore the impact of 18F-FDG-PET on both the diagnosis and management of CS. Additionally, this study aimed to investigate any differences in patient outcomes based on the results of their first follow-up 18F-FDG-PET scan. Methods Medical records of 69 patients with CS who underwent at least one 18F-FDG-PET scan were analyzed. The study calculated the proportion of 18F-FDG PET scans influencing CS treatment and diagnosis, with 56 patients undergoing at least two scans. Among these, 53 patients were categorized into two groups based on their first follow-up scan results (group 1:no change/progress, group 2:regress). Statistical analyses included independent t-tests, the Mann-Whitney test, and Fisher's exact test. Outcome measures included death, heart transplantation or aborted cardiac death, with survival analyzed by Kaplan-Meier statistics. Results Among 69 patients, 204 18F-FDG-PET scans were conducted, with 47% directly influencing treatment decisions. Twenty-five patients were diagnosed with CS through 18F-FDG-PET. While no significant differences were observed regarding demographics and clinical features, the results suggested potential differences in event-free survival (p=0.084;Figure 1) and sex (p=0.08) between the groups. Conclusions 18F-FDG-PET has emerged as a pivotal tool in regulating treatment, diagnosing, and monitoring CS patients, playing a fundamental role in assessing treatment response. However, further studies are needed.

Predictive value of cardiac 18F-fluorodeoxyglucose positron emission tomography for fatal ventricular arrhythmic events in patients with cardiac sarcoidosis

Abstract Background Patients with cardiac sarcoidosis (CS) face an elevated risk of fatal ventricular arrhythmic events (FVAE), including sudden cardiac death. Late gadolinium enhancement (LGE) from contrast-enhanced cardiac magnetic resonance is used for diagnosis of CS and estimation of FVAE risk. However, its application is limited in cases with cardiac devices, renal failure or contrast agent allergies. 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) emerges as a diagnostic tool for CS, even in cases where LGE is not feasible. Purpose This study aimed to investigate the potential utility of FDG-PET in predicting FVAE in patients with CS by hypothesizing that higher or lower percent FDG uptake could predict the FVAE risk. Methods Cardiac FDG-PET data from 121 patients with CS, acquired at our university hospital between March 2008 and November 2020, were analyzed. A polar-map model was used to calculate percent uptake relative to maximal cardiac FDG uptake in each of the American Heart Association (AHA) 17 segments (Figure A). Percent uptakes of the AHA 17 segments were compared between groups with and without future FVAE. LGE information was available in 82 patients and was used to assess the presence of LGE in regions where percent FDG uptake differed between the two groups. Results Among enrolled patients (mean age 59.5 ± 10.0 years, 67.8% women), 43 experienced FVAE following FDG-PET image acquisition. The group with future FVAE had a higher history of FVAE (7.7% vs. 37.2%) and beta-blocker administration (38.5% vs. 60.5%), larger left ventricular diastolic diameter (LVDd) (49.3 ± 7.3 mm vs. 57.4 ± 9.5 mm) and lower ejection fraction (LVEF) (56.6 ± 13.6% vs. 42.0 ± 15.2%) compared to the group without it (P &amp;lt; 0.05 all). Percent FDG uptake in the basal interventricular septum part (segment 3) (Figure A) was lower in patients with future FVAE compared to those without it (54.4 ± 13.8% vs. 41.8 ± 15.2%, P &amp;lt; 0.001 corrected for multiple comparisons). Kaplan-Meier analysis with a median split of percent FDG uptake in segment 3 showed that patients with lower uptake (&amp;lt;49%, N= 62) had lower FVAE-free survival compared to those with higher uptake (≥49%, N = 59) (P = 0.007) (Figure B). A Cox hazard model also demonstrated an association between percent FDG uptake in segment 3 and FVAE onset (hazard ratio 0.972 [95% CI 0.951, 0.995], P = 0.015) after adjusting for previous FVAE, beta-blocker administration, LVDd and LVEF. Similarly, analysis within the subgroup with LGE in the septum (N = 58) revealed a higher risk of FVAE in the group with lower percent FDG uptake compared to those with higher uptake (P = 0.020) (Figure C(a)). However, this association was not evident in patients without LGE in the septum (N = 24) (P = 0.821) (Figure C(b)). Conclusions Reduced percent FDG uptake with LGE in the basal intraventricular septum may serve as a valuable predictor of future FVAE occurrence in patients with CS.

Association of left ventricular ejection fraction improvement with prognosis in patients with cardiac sarcoidosis: insights from the ILLUMINATE-CS study

Abstract Introduction While the beneficial impact of enhancing left ventricular ejection fraction (LVEF) is well-documented in patients with heart failure with reduced LVEF, its relevance in cardiac sarcoidosis (CS) remains unclear. Purpose This study aimed to identify predictive factors for LVEF improvement and explore its association with prognosis in patients with CS. Methods A post-hoc analysis of the ILLUMINATE-CS registry, a retrospective observational study across multiple centers, was conducted. CS diagnosis adhered to either the 2016 Japanese Circulation Society guidelines or the 2014 Heart Rhythm Society expert consensus statement. Patients with baseline LVEF ≥50% were excluded in the current analysis. LVEF improvement was quantified as the variance between baseline and follow-up echocardiography. Patients were categorized into tertiles based on LVEF improvement: 1st tertile (≤0%, least improved), 2nd tertile (0–9%), and 3rd tertile (&amp;gt;9%, most improved) groups. The primary outcome was all-cause mortality after follow-up echocardiography. Results Among 188 enrolled patients (mean age 62.1±10.7 years; 42.6% male), 65, 60, and 63 were allocated to the 1st, 2nd, and 3rd tertile groups, respectively. Multivariate linear regression analysis revealed that narrower QRS duration, lower baseline LVEF, and absence of beta-blocker prescription at baseline were independently associated with greater LVEF improvement. Over a median follow-up of 407 days, 26 all-cause deaths occurred. Kaplan–Meier curves exhibited significant difference among the tertile groups (log-rank, P=0.002). Cox proportional hazard analysis, adjusted for possible prognostic factors including LVEF, demonstrated significantly higher mortality in the 1st and 2nd tertile groups compared to the 3rd tertile group (vs. 1st tertile: hazard ratio [HR] 22.14, 95% confidence interval [CI] 2.73–179.50, P=0.004; vs. 2nd tertile: HR 8.17, 95% CI 1.02–65.71, P=0.048). Additionally, treating LVEF improvement as a continuous variable revealed an independent association with increased mortality (LVEF improvement per 5%: HR 0.69, 95% CI 0.54–0.87, P=0.002). Conclusions Improvement LVEF in patients with CS is significantly associated with improved outcomes, highlighting its clinical importance in managing CS.Kaplan–Meier curves for all-cause death

Cardiac sarcoidosis: diagnosis and management.

Non-caseating granulomatous infiltration of the myocardium is the hallmark of cardiac sarcoidosis (CS). CS manifests clinically as conduction disturbance, ventricular arrhythmia, sudden cardiac death and/or heart failure with reduced ejection fraction. Other than confirmation through endomyocardial biopsy, a diagnosis of probable CS can be established by histological evidence of systemic sarcoidosis in addition to characteristic clinical or advanced imaging findings. Cardiac Magnetic Resonance imaging (CMR) and 18F-flurodeoxyglycose positron emission tomography (FDG-PET) are imaging modalities indispensable in the diagnosis and monitoring of CS. FDG-PET is the method of choice for identifying the active inflammatory phase of CS and in the monitoring and modifying of immunosuppressive treatment. CMR is better suited for assessing cardiac morphology and function. Both modalities are more effective in detecting CS when used in combination than either is alone. Management of CS is primarily based upon observational data of low quality due to a paucity of randomized controlled trials. Corticosteroid therapy and/or tiered-immunosuppression are the mainstays of treatment in reducing myocardial inflammation. Steroid-sparing agents aim to limit the unfavorable side-effects of a significant steroid burden. Antiarrhythmics and guideline-directed medical therapies are utilized for control of ventricular arrhythmia and left ventricular dysfunction respectively. CS necessitates multidisciplinary care in specialized centers to most effectively diagnose and manage the disease. Additional randomized trials are warranted to further our understanding of medical optimization in CS.

Can FDG-PET Imaging Identify Cardiac Sarcoidosis Disease Phenotypes?

Despite the scarcity of data, most guidelines have advocated for the treatment of cardiac sarcoidosis with corticosteroids. However, there is heterogeneity in disease presentation and response to treatment, which can make treatment challenging. The ability to identify disease phenotypes to allow for tailored therapy is therefore highly desirable. This review will seek to outline the disease phenotypes of cardiac sarcoidosis and the role that FDG-PET imaging can play in identifying these phenotypes to optimize disease diagnosis and treatment management. FDG PET can identify cardiac sarcoidosis and is being increasingly used to monitor therapeutic response to immunosuppressive therapy, to follow treatment response after discontinuation of corticosteroid therapy, and to evaluate for disease relapse. Modern quantitative techniques using FDG PET imaging may allow for even better phenotypic disease characterization and the ability to track the response to immunosuppression more accurately. FDG PET currently plays an important role in cardiac sarcoidosis diagnosis. However, it also affords us the opportunity to offer insights into cardiac sarcoidosis disease phenotypes to better understand the underlying disease process and in the future may allows us to tailor therapies accordingly.

Current Practices and Emerging Therapies to Optimize Heart Failure Management in Cardiac Sarcoidosis: A Systematic Review.

Cardiac sarcoidosis (CS) is a distinctive manifestation of sarcoidosis, a multisystemic inflammatory disorder that is characterized by non-necrotizing granulomas. CS can lead to arrhythmias, heart failure (HF), and sudden cardiac death. The diagnosis of CS involves imaging in the form of a two-dimensional echocardiogram, cardiac magnetic resonance imaging (MRI), an 18-fluoro-deoxyglucose positron emission tomography (FDG-PET) scan, and an endomyocardial biopsy. Treatment of CS entails corticosteroids, immunosuppressive agents, monoclonal antibodies, and, in advanced cases, heart transplantation (HTx). This systematic review follows Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines, focusing on HF in sarcoidosis patients. Eligibility criteria include recent (2019-2024) research papers on sarcoidosis-induced heart failure, excluding other causes. The databases searched were PubMed, Google Scholar, and ScienceDirect. From 36,755 initial articles, 2,060 remained after filtering, and 17 were selected for quality assessment. Based on quality assessment, 11 studies were included in the final review. In CS, a variety of treatment strategies can be implemented. Corticosteroids are the first-line therapeutic options, and in the majority of cases, they are very successful in controlling the disease progression. Immunosuppressive agents like methotrexate and azathioprine are used to avoid long-term steroid use. Both corticosteroids and immunosuppressives act by reducing inflammation and preventing myocardial scarring. Biological agents like infliximab and adalimumab prevent disease progression by targeting specific inflammatory pathways and are used in refractory cases. Regular HF management drugs like angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), sodium-glucose transport protein 2 (SGLT2) inhibitors, beta-blockers, and diuretics help in optimizing cardiac function. In severe cases, a left ventricular assist device (LVAD) may be required. The ultimate treatment for end-stage CS is HTx, which has to be supplemented with a strong, individualized regimen of glucocorticoids and immunosuppressives to avoid graft rejection and to control sarcoidosis. Due to a lack of standard protocols for management and limited knowledge about CS, the ideal treatment of HF is still a matter of debate. Hence, further research and clinical trials need to be performed to optimize patient outcomes.

Cardiac Sarcoidosis: Utilizing Cardiac MRI and PET-CT.

Cardiac sarcoidosis is an inflammatory condition that has been associated with deleterious cardiac manifestations. The diagnosis of cardiac sarcoidosis is challenging and can be guided by advanced cardiac imaging. Endomyocardial biopsy lacks sensitivity in confirming a diagnosis of cardiac sarcoidosis. Studies have shown that the use of cardiac magnetic resonance imaging (MRI) and cardiac Positron Emission Testing (PET) are associated with increased sensitivity and specificity in the diagnosis of cardiac sarcoidosis. Cardiac MRI and cardiac PET CT, although distinct entities, are complimentary in the diagnosis, prognostication of major cardiac events, and aid in the treatment algorithm in patients with cardiac sarcoidosis.

Role of Textural Analysis Parameters Derived from FDG PET/CT in Diagnosing Cardiac Sarcoidosis

Abstract Introduction Texture and radiomic analysis characterize the lesion's phenotype and evaluate its microenvironment in quantitative terms. The aim of this study was to investigate the role of textural features of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography–computed tomography (PET/CT) images in differentiating patients with cardiac sarcoidosis (CS) from patients with physiologic myocardial uptake. Methods This is a retrospective, single-center study of 67 patients, 17 diagnosed CS patients, and 50 non-CS patients. These patients underwent FDG PET/CT for the diagnosis of CS. The non-CS group underwent 18F-FDG PET/CT for other oncological indications. The PET/CT images were then processed in a commercially available textural analysis software. Region of interest was drawn over primary tumor with a 40% threshold and was processed further to derive 92 textural and radiomic parameters. These parameters were then compared between the CS group and the non-CS group. Receiver operating characteristics (ROC) curves were used to identify cutoff values for textural features with a p-value &lt; 0.05 for statistical significance. These parameters were then passed through a principle component analysis algorithm. Five different machine learning classifiers were then tested on the derived parameters. Results A retrospective study of 67 patients, 17 diagnosed CS patients, and 50 non-CS patients, was done. Twelve textural analysis parameters were significant in differentiating between the CS group and the non-CS group. Cutoff values were calculated for these parameters according to the ROC curves. The parameters were Discretized_HISTO_Entropy, GLCM_Homogeneity, GLCM_Energy, GLRLM_LRE, GLRLM_LGRE, GLRLM_SRLGE, GLRLM_LRLGE, NGLDM_Coarseness, GLZLM_LZE, GLZLM_LGZE, GLZLM_SZLGE, and GLZLM_LZLGE. The gradient boosting classifier gave best results on these parameters with 85.71% accuracy and an F1 score of 0.86 (max 1.0) on both classes, indicating the classifier is performing well on both classes. Conclusion Textural analysis parameters could successfully differentiate between the CS and non-CS groups noninvasively. Larger multicenter studies are needed for better clinical prognostication of these parameters.

Cardiac sarcoidosis and neurosarcoidosis - multidisciplinary approach for diagnosis.

The current review aims to highlight the role of multidisciplinary approach in the diagnosis of patients with cardiac and neurosarcoidosis. Multidisciplinary approach integrates the available clinical information, imaging and histopathological results aiming to reach a definite or at least provisional diagnosis and allow appropriate management. Multidisciplinary approach is the reference standard for diagnosis of interstitial lung disease and should be strongly considered in complex clinical conditions such as cardiac sarcoidosis (CS) and neurosarcoidosis. Histopathological confirmation of noncaseating granulomatous inflammation provides a definite diagnosis of sarcoidosis involving any organ. However, a provisional high confidence or even definite clinical diagnosis can be reached using multidisciplinary evaluation of all available evidence. The diagnosis of cardiac sarcoidosis and neurosarcoidosis requires the integration of different expertise based on the current diagnostic criteria sets. Identifying typical or at least compatible patterns on advanced imaging modalities (CMR and Fluro-Deoxy-Glucose Positron Emission Tomography (FDG-PET)) seems key for the diagnosis of CS, while a confident diagnosis of extra-cardiac disease supports an at least provisional diagnosis. Similarly, in neurosarcoidosis integrating compatible MRI appearances and cerebrospinal fluid results in patients with systemic sarcoidosis allows an at least provisional diagnosis. Exclusion of alternative differential diagnoses is crucial and requires high clinical suspicion, imaging review expertise and appropriate tests performance. There have been considerable advances in the diagnostic approach of patients with cardiac and neurosarcoidosis. Multidisciplinary approach for both diagnosis and management is required to reach a confident clinical diagnosis and should be applied when possible.

Isolated cardiac sarcoidosis: a case report

Introduction. Ventricular arrhythmias are a risk factor for sudden cardiac death. Abnormalities of cardiac rhythm and conduction may be the only subjective manifestation of isolated cardiac sarcoidosis, which occurs in 25% of the total number of patients with this disease.Brief description. We present a case of isolated cardiac sarcoidosis in a young female patient, the main clinical manifestation of which was attacks of palpitations caused by ventricular tachycardia and episodes of cardiogenic shock without a cardiovascular history. Echocardiography and contrast-enhanced cardiac magnetic resonance imaging (MRI) revealed asymmetric left ventricular hypertrophy and focal myocardial masses. Cardiac tumor and sarcoidosis were suspected. The final diagnosis was based on the results of histological and immunohistochemical analysis of endomyocardial biopsies documenting sarcoidosis. No systemic manifestations of sarcoidosis were found.Discussion. The case demonstrates the potential of a comprehensive paraclinical study in the diagnosis of cardiac sarcoidosis and its differential diagnosis with other cardiac pathologies.Conclusion. Cardiac sarcoidosis is difficult to diagnose and requires histological verification in patients with LV hypertrophy and arrhythmias, and physicians should be aware about this rare disease with unfavorable prognosis without specific treatment.

Use of 18F-fluorodeoxyglucose positron emission tomography in the differential diagnosis of arrhythmogenic right ventricular cardiomyopathy and cardiac sarcoidosis

Abstract Introduction Arrhythmogenic Cardiomyopathy (ACM) is defined as an arrhythmogenic heart muscle disorder not explained by ischemic, hypertensive, or valvular heart disease, which ranges from a systemic immunologic disorder such as cardiac sarcoidosis (CS), to a genetically determined one (arrhythmogenic right ventricular cardiomyopathy=ARVC). The aim of this study was to assess the utility of 18F-fluordeoxyglucose positron emission tomography /computer tomography (18F-FDG-PET/CT) in the differential diagnosis of ACM. Methods This study included 45 patients with a definite diagnosis of ARVC, in whom 18F-FDG-PET/CT was performed to screen for CS. Following a positive PET, diagnosis of CS was pursued according to the 2014 HRS consensus document. The patients were divided into two cohorts: the ARVC Cohort (ARVC-C) and the Cardiac Sarcoidosis Cohort (CS-C). Results All 45 patients received an 18F-FDG-PET/CT, of these 5 had a positive PET showing myocardial hypermetabolism. All 5 patients with a positive PET had a final diagnosis of histologically confirmed CS, as such the 18F-FDG-PET/CT had a negative predictive value (NPV) of 100%. All 45 patients also received genetic testing (cardiomyopathy panel). In the ARVC-C, 23 (58%) patients harbored a pathogenic (P)/likely pathogenic (LP) variant (40% in PKP2). In the CS-C, 1 (20%) patient with histologically confirmed CS harbored a LP DSG2 variant. Nine (23%) subjects in the ARVC-C presented with atrioventricular block (AVB) (grade I) and 7 (18%) with QRS fragmentation, whereas 5 (100%) patients in the CS-C presented with AVB (grade I and higher) and 4 (80%) with QRS fragmentation. On TTE, left ventricular (LV) involvement was less frequent in the ARVC-C (LVEF 52.2 +/- 8.7%; wall motion abnormalities in 19 patients (48%)), while LV-involvement in the CS-C was more frequent (LVEF 44.0 +/- 16.2%; wall motion abnormalities in 3 (60%). On cardiac magnetic resonance imaging (cMRI), late gadolinium enhancement was present in the ARVC-C in 14 (35%) in the RV and 15 (38%) in the LV, while it was present in 3 (60%) patients in the RV and 3 (60%) in the LV in the CS-C. Conclusions CS is an underdiagnosed clinical entity, which can be challenging to differentiate from ARVC. 18F-FDG-PET/CT has a high NPV to exclude CS in patients fulfilling definite ARVC criteria. Hence, we recommend to offer 18F-FDG-PET/CT to patients fulfilling definite ARVC criteria who present with AVB, QRS fragmentation, or biventricular involvement to screen for CS, especially to those who do not have an LP/P variant in the PKP2 gene.

Coexistence of cardiac sarcoidosis and genetic cardiomyopathies: a conundrum

Abstract Introduction Cardiac sarcoidosis (CS) is a chronic inflammatory disease characterized histologically by the formation of non-caseating granuloma in the myocardium, however, causes remain largely unknown. Genetic arrhythmogenic cardiomyopathy (ACM) is an important differential diagnosis of CS. Until now, few data are available about the coexistence of CS in a patient with genetic ACM harboring a desmoglein-2 (DSG2) variant. Purpose We report a case series of patients who demonstrate coexistence of histologically proven CS and genetic ACM. Methods This is a multicentric study, which included patients from four high-volume cardiology referral centres for heart failure and ACM in Switzerland, Italy, and Austria. Patients with both a biopsy-proven diagnosis of sarcoidosis with cardiac involvement (according to the 2014 HRS criteria) also harboring a pathogenic/likely pathogenic (P/LP) variant for cardiomyopathy-associated genes were 1:1 matched for age, gender and genetic variant with patients with genetic ACM without CS (Gen-only). Clinical and imaging data (echocardiography (TTE), cardiac magnetic resonance (CMR) and positron-emission tomography (18FFDG-PET/CT) were collected. Results Each group included 5 patients (Gen+CS: age 48 ± 11 years, Gen only: age 52 ± 13.7 years, n=3 (60%) female in both groups). For each group, the following genes with P/LP variants were found: PKP2: n=2 (40%), DSG2: n=1 (20%), DSP: n=1 (20%), TTN: n=1 (20%). In patients with Gen+CS, atrio-ventricular block (AVB) I° (80% vs 20%, p=0.05) and paroxysmal atrial fibrillation (80% vs 0%, p=0.004) were more frequent, and median NT-proBNP levels (1346ng/l, IQR:103-4276 vs. 214ng/l, IQR:131-326, p=0.046), as well as high-sensitive C-reactive protein levels were higher (3.1g/dl, IQR:1.1-24.2 vs. 0.7g/dl, IQR:0.3-0.95, p=0.016). On imaging, Gen+CS patients were more likely to have septal involvement (60% vs 0%, p=0.021), as highlighted by positive late-gadolinium enhancement on CMR, metabolic activity on PET, or focal wall motion anomalies on TTE. Conclusions CS and genetic ACM can coexist. Hence, detection of a P/LP genetic variant associated with ACM should not lead to exclusion of CS, which more frequently presents with AVB, septal involvement, heart failure, and metabolic activity on imaging. On the contrary, CS can be associated with genetic variants in cardiomyopathy-associated genes.FDG-PET/CT

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

Papillary muscle (PM) activity may demonstrate true active cardiac sarcoidosis (CS) or mimic CS in 18FDG-PET/CT if adequate myocardial suppression (MS) is not achieved. We aim to examine whether PM uptake can be used as a marker of failed MS and measure the rate of PM activity presence in active CS with different dietary preparations. We retrospectively reviewed PET/CTs obtained with three different dietary preparations. Diet-A: 24-h ketogenic diet with overnight fasting (n = 94); Diet-B: 18-h fasting (n = 44); and Diet-C: 72-h daytime ketogenic diet with 3-day overnight fasting (n = 98). Each case was evaluated regarding CS diagnosis (negative, positive, and indeterminant) and presence of PM activity. MaxSUV was measured from bloodpool, liver, and the most suppressed normal myocardium. Linear mixed-effects models were used to compare these factors between those with PM activity and those without. PM activity was markedly lower in the Diet-C group compared with others: Diet-C: 6 (6.1%), Diet-A: 36 (38.3%), and Diet-B: 26 (59.1%) (p < 0.001). MyocardiumMaxSUV was higher, and MyocardiummaxSUV/BloodpoolmaxSUV, MyocardiummaxSUV/LivermaxSUV ratios were significantly higher in the cases with PM activity (p < 0.001). Among cases that used Diet-C and had PM activity, 66.7% were positive and 16.7% were indeterminate. If Diet-A or Diet-B was used, those with PM activity had a higher proportion of indeterminate cases (Diet-A: 61.1%, Diet-B: 61.5%) than positive cases (Diet-A: 36.1%, Diet-B: 38.5%). Lack of PM activity can be a sign of appropriate MS. PM activity is less common with a specific dietary preparation (72-h daytime ketogenic diet with 3-day overnight fasting), and if it is present with this particular preparation, the likelihood that the case being true active CS might be higher than the other traditional dietary preparations.

The usefulness of speckle tracking echocardiography for the prediction of cardiac involvement in patients with biopsy-proven sarcoidosis.

Cardiac sarcoidosis (CS) is commonly diagnosed based on clinical criteria and abnormalities in noninvasive imaging reported in patients with biopsy-proven extracardiac sarcoidosis. Electrocardiogram and two-dimensional echocardiography have a low sensitivity for CS detection. Cardiovascular magnetic resonance imaging (CMR) and positron emission tomography (PET) have limitations in terms of cost and availability. This study aimed to assess the usefulness of left ventricular longitudinal strain, measured using two-dimensional speckle tracking echocardiography (STE), for the prediction of late gadolinium enhancement (LGE) presence in CMR in patients with biopsy-proven sarcoidosis. A total of 119 patients with biopsy-proven extracardiac sarcoidosis were divided, according to the clinical criteria proposed by the 2014 Heart Rhythm Society expert consensus statement (HRS 2014), into two groups: 43 individuals with "probable cardiac sarcoidosis", CS(+) and 76 individuals without cardiac sarcoidosis, CS (-). Data from echocardiography, CMR, 12-lead ECG and 24h Holter monitoring were analyzed. Left ventricular global longitudinal strain (LV-GLS) was slightly reduced in the entire sarcoidosis group (-18.61±2.96), no difference between the CS (+) and CS (-) subgroups was found (-18.0%±3.2% and -18.9%±2.8%, respectively; p=.223). No cut-off value for LV-GLS was identified that could predict the presence of LGE. Segmental longitudinal strain impairment partially correlated with the presence of LGE on CMR. In our cohort of sarcoidosis patients, segmental longitudinal strain proved more helpful in the diagnostic process than LV-GLS. The ultimate role of STE in the diagnosis of CS remains to be established.