Risk and predictors of sudden death in cardiac sarcoidosis: A systematic review and meta-analysis

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.

Cardiac Magnetic Resonance and Cardiac Implantable Electronic Devices: Are They Truly Still "Enemies"?

The application of cardiac magnetic resonance (CMR) imaging in clinical practice has grown due to technological advancements and expanded clinical indications, highlighting its superior capabilities when compared to echocardiography for the assessment of myocardial tissue. Similarly, the utilization of implantable cardiac electronic devices (CIEDs) has significantly increased in cardiac arrhythmia management, and the requirements of CMR examinations in patients with CIEDs has become more common. However, this type of exam often presents challenges due to safety concerns and image artifacts. Until a few years ago, the presence of CIED was considered an absolute contraindication to CMR. To address these challenges, various technical improvements in CIED technology, like the reduction of the ferromagnetic components, and in CMR examinations, such as the introduction of new sequences, have been developed. Moreover, a rigorous protocol involving multidisciplinary collaboration is recommended for safe CMR examinations in patients with CIEDs, emphasizing risk assessment, careful monitoring during CMR, and post-scan device evaluation. Alternative methods to CMR, such as computed tomography coronary angiography with tissue characterization techniques like dual-energy and photon-counting, offer alternative potential solutions, although their diagnostic accuracy and availability do limit their use. Despite technological advancements, close collaboration and specialized staff training remain crucial for obtaining safe diagnostic CMR images in patients with CIEDs, thus justifying the presence of specialized centers that are equipped to handle these type of exams.

Relationship of Mild to Moderate Impairment of Left Ventricular Ejection Fraction With Fatal Ventricular Arrhythmic Events in Cardiac Sarcoidosis

BACKGROUND

Current guidelines recommend placing an implantable cardiac defibrillator for patients with cardiac sarcoidosis and a severely impaired left ventricular ejection fraction (LVEF) of ≤35%. In this study, we determined the association between mild or moderate LVEF impairment and fatal ventricular arrhythmic event (FVAE).

METHODS AND RESULTS

We retrospectively analyzed 401 patients with cardiac sarcoidosis without sustained ventricular arrhythmia at diagnosis. The primary end point was an FVAE, defined as the combined endpoint of documented ventricular tachycardia or ventricular fibrillation and sudden cardiac death. Two cutoff points for LVEF were used: a sex-specific lower threshold of normal range of LVEF (52% for men and 54% for women) and an LVEF of 35%, which is used in the current guidelines. During a median follow-up of 3.2 years, 58 FVAEs were observed, and the 5- and 10-year estimated incidences of FVAEs were 16.8% and 23.0%, respectively. All patients were classified into 3 groups according to LVEF: impaired LVEF group, mild to moderate impairment of LVEF group, and maintained LVEF group. Multivariable competing risk analysis showed that both the impaired LVEF group (hazard ratio [HR], 3.24 [95% CI, 1.49-7.04]) and the mild to moderate impairment of LVEF group (HR, 2.16 [95% CI, 1.04-4.46]) were associated with a higher incidence of FVAEs than the maintained LVEF group after adjustment for covariates.

CONCLUSIONS

Patients with cardiac sarcoidosis are at a high risk of FVAEs, regardless of documented ventricular arrhythmia at the time of diagnosis. In patients with cardiac sarcoidosis, mild to moderate impairment of LVEF is associated with FVAEs.

Sex differences in clinical characteristics and prognosis of patients with cardiac sarcoidosis

OBJECTIVE

Owing to the paucity of data, this study aimed to investigate sex differences in clinical features and prognosis of patients with cardiac sarcoidosis (CS).

METHODS

This study was a secondary analysis of the ILLUstration of the Management and prognosIs of JapaNese PATiEnts with Cardiac Sarcoidosis registry-a retrospective multicentre registry that enrolled patients with CS between 2001 and 2017. The primary outcome was potentially fatal ventricular arrhythmia events (pFVAEs)-a composite of sudden cardiac death, sustained ventricular tachycardia lasting >30 s, ventricular fibrillation or the requirement for implantable cardioverter defibrillator therapy.

RESULTS

Of the 512 participants (mean age±SD 61.6±11.4 years), 329 (64.2%) were females. Both sexes had peak ages of 60-64 years at diagnosis. Male patients were younger and had a higher prevalence of coronary artery disease and lower left ventricular ejection fraction than female patients. During a median follow-up of 3 years (IQR 1.6-5.6), pFVAEs were observed in 99 patients, with males having a significantly higher risk than females (p=0.002). This association was retained even after adjustment for other risk factors for pFVAEs, including left ventricular ejection fraction (adjusted HR 1.80; 95% CI 1.08 to 3.01, p=0.025).

CONCLUSION

Approximately two-thirds of patients with CS were females, with a peak age of approximately 60 years at clinical diagnosis in both sexes; male patients were younger than female patients. Male patients had a significantly higher risk of pFVAEs than female patients.

TRIAL REGISTRATION NUMBER

UMIN000034974.

Prognostic Value of RV Abnormalities on CMR in Patients With Known or Suspected Cardiac Sarcoidosis

BACKGROUND

Left ventricular abnormalities in cardiac sarcoidosis (CS) are associated with adverse cardiovascular events, whereas the prognostic value of right ventricular (RV) involvement found on cardiac magnetic resonance is unclear.

OBJECTIVES

This study aimed to systematically assess the prognostic value of right ventricular ejection fraction (RVEF) and RV late gadolinium enhancement (LGE) in known or suspected CS.

METHODS

This study was prospectively registered in PROSPERO (CRD42022302579). PubMed, Embase, and Web of Science were searched to identify studies that evaluated the association between RVEF or RV LGE on clinical outcomes in CS. A composite endpoint of all-cause death, cardiovascular events, or sudden cardiac death (SCD) was used. A meta-analysis was performed to determine the pooled risk ratio (RR) for these adverse events. The calculated sensitivity, specificity, and area under the curve with 95% CIs were weighted and summarized.

RESULTS

Eight studies including a total of 899 patients with a mean follow-up duration of 3.2 ± 0.7 years were included. The pooled RR of RV systolic dysfunction was 3.1 (95% CI: 1.7-5.5; P < 0.01) for composite events and 3.0 (95% CI: 1.3-7.0; P < 0.01) for SCD events. In addition, CS patients with RV LGE had a significant risk for composite events (RR: 4.8 [95% CI: 2.4-9.6]; P < 0.01) and a higher risk for SCD (RR: 9.5 [95% CI: 4.4-20.5]; P < 0.01) than patients without RV LGE. Furthermore, the pooled area under the curve, sensitivity, and specificity of RV LGE for identifying patients with CS who were at highest SCD risk were 0.8 (95% CI: 0.8-0.9), 69% (95% CI: 50%-84%), and 90% (95% CI: 70%-97%), respectively.

CONCLUSIONS

In patients with known or suspected CS, RVEF and RV LGE were both associated with adverse events. Furthermore, RV LGE shows good discrimination in identifying CS patients at high risk of SCD.

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.

Evaluation and Catheter Ablation of Ventricular Arrhythmias in Cardiac Sarcoidosis

Ventricular arrhythmias are a common clinical manifestation in patients with cardiac sarcoidosis (CS) and other arrhythmogenic inflammatory cardiomyopathies (AIC). The management of sustained ventricular arrhythmias in these patients presents unique challenges. Current therapies include immunosuppressive, antiarrhythmic agents, and catheter ablation. Significant progress has been made in deciphering the importance of patient selection for ablation, systematic preablation evaluation, and optimal ablation timing, as well as ablation approaches and techniques. In this overview, we discuss the evaluation and management of ventricular arrhythmias in patients with CS, focusing on catheter ablation, which has evolved into an effective approach in reducing the burden of ventricular arrhythmias in these patients in the context of multifaceted treatment along with medical therapies.

Cardiovascular Magnetic Resonance Imaging Phenotypes and Long-term Outcomes in Patients With Suspected Cardiac Sarcoidosis

Importance

In patients with sarcoidosis with suspected cardiac involvement, late gadolinium enhancement (LGE) on cardiovascular magnetic resonance imaging (CMR) identifies those with an increased risk of adverse outcomes. However, these outcomes are experienced by only a minority of patients with LGE, and identifying this subgroup may improve treatment and outcomes in these patients.

Objective

To assess whether CMR phenotypes based on left ventricular ejection fraction (LVEF) and LGE in patients with suspected cardiac sarcoidosis (CS) are associated with adverse outcomes during follow-up.

Design, Setting, and Participants

This cohort study included consecutive patients with histologically proven sarcoidosis who underwent CMR for the evaluation of suspected CS from 2004 to 2020 with a median follow-up of 4.3 years at an academic medical center in Minnesota. Demographic data, medical history, comorbidities, medications, and outcome data were collected blinded to CMR data.

Exposures

CMR phenotypes were identified based on LVEF and LGE presence and features. LGE was classified as pathology-frequent or pathology-rare based on the frequency of cardiac damage features on gross pathology assessment of the hearts of patients with CS who had sudden cardiac death or cardiac transplant.

Main Outcomes and Measures

Composite of ventricular arrhythmic events and composite of heart failure events.

Results

Among 504 patients (mean [SD] age, 54.1 [12.5] years; 242 [48.0%] female and 262 [52.0%] male; 2 [0.4%] American Indian or Alaska Native, 6 [1.2%] Asian, 90 [17.9%] Black or African American, 399 [79.2%] White, 5 [1.0%] of 2 or more races (including the above-mentioned categories and Native Hawaiian or Other Pacific Islander), and 2 [0.4%] of unknown race; 4 [0.8%] Hispanic or Latino, 498 [98.8%] not Hispanic or Latino, and 2 [0.4%] of unknown ethnicity), 4 distinct CMR phenotypes were identified: normal LVEF and no LGE (n = 290; 57.5%), abnormal LVEF and no LGE (n = 53; 10.5%), pathology-frequent LGE (n = 103; 20.4%), and pathology-rare LGE (n = 58; 11.5%). The phenotype with pathology-frequent LGE was associated with a high risk of arrhythmic events (hazard ratio [HR], 12.12; 95% CI, 3.62-40.57; P < .001) independent of LVEF and extent of left ventricular late gadolinium enhancement (LVLGE). It was also associated with a high risk of heart failure events (HR, 2.49; 95% CI, 1.19-5.22; P = .02) independent of age, pulmonary hypertension, LVEF, right ventricular ejection fraction, and LVLGE extent. Risk of arrhythmic events was greater with an increasing number of pathology-frequent LGE features. The absence of the pathology-frequent LGE phenotype was associated with a low risk of arrhythmic events, even in the presence of LGE or abnormal LVEF.

Conclusions and Relevance

This cohort study found that a CMR phenotype involving pathology-frequent LGE features was associated with a high risk of arrhythmic and heart failure events in patients with sarcoidosis. The findings indicate that CMR phenotypes could be used to optimize clinical decision-making for treatment options, such as implantable cardioverter-defibrillators.

Risk stratification of patients with cardiac sarcoidosis: the ILLUMINATE-CS registry

AIMS

This study evaluated the prognosis and prognostic factors of patients with cardiac sarcoidosis (CS), an underdiagnosed disease.

METHODS AND RESULTS

Patients from a retrospective multicentre registry, diagnosed with CS between 2001 and 2017 based on the 2016 Japanese Circulation Society or 2014 Heart Rhythm Society criteria, were included. The primary endpoint was a composite of all-cause death, hospitalization for heart failure, and documented fatal ventricular arrhythmia events (FVAE), each constituting exploratory endpoints. Among 512 registered patients, 148 combined events (56 heart failure hospitalizations, 99 documented FVAE, and 49 all-cause deaths) were observed during a median follow-up of 1042 (interquartile range: 518-1917) days. The 10-year estimated event rates for the primary endpoint, all-cause death, heart failure hospitalizations, and FVAE were 48.1, 18.0, 21.1, and 31.9%, respectively. On multivariable Cox regression, a history of ventricular tachycardia (VT) or fibrillation [hazard ratio (HR) 2.53, 95% confidence interval (CI) 1.59-4.00, P < 0.001], log-transformed brain natriuretic peptide (BNP) levels (HR 1.28, 95% CI 1.07-1.53, P = 0.008), left ventricular ejection fraction (LVEF) (HR 0.94 per 5% increase, 95% CI 0.88-1.00, P = 0.046), and post-diagnosis radiofrequency ablation for VT (HR 2.65, 95% CI 1.02-6.86, P = 0.045) independently predicted the primary endpoint.

CONCLUSION

Although mortality is relatively low in CS, adverse events are common, mainly due to FVAE. Patients with low LVEF, with high BNP levels, with VT/fibrillation history, and requiring ablation to treat VT are at high risk.

Non-invasive Imaging in Women With Heart Failure - Diagnosis and Insights Into Disease Mechanisms

PURPOSE OF REVIEW

To summarise the role of different imaging techniques for diagnosis and investigation of heart failure in women.

RECENT FINDINGS

Although sex differences in heart failure are well recognised, and the scope of imaging techniques is expanding, there are currently no specific guidelines for imaging of heart failure in women. Diagnosis and stratification of heart failure is generally performed first line using transthoracic echocardiography. Understanding the aetiology of heart failure is central to ongoing management, and with non-ischaemic causes more common in women, a multimodality approach is generally required using advanced imaging techniques including cardiovascular magnetic resonance imaging, nuclear imaging techniques, and cardiac computed tomography. There are specific considerations for imaging in women including radiation risks and challenges during pregnancy, highlighting the clear unmet need for cardiology and imaging societies to provide imaging guidelines specifically for women with heart failure.

Enhanced oxidative stress and presence of ventricular aneurysm for risk prediction in cardiac sarcoidosis

OBJECTIVE

Sudden cardiac death (SCD) is the major cause of death in cardiac sarcoidosis (CS). We aimed to identify the prognostic markers for sustained ventricular tachycardia (sVT) and SCD in patients with CS.

METHODS

We performed a prospective observational cohort study for patients with CS diagnosed according to the Japanese or Heart Rhythm Society guidelines between June 2008 and March 2020 in our hospital. The primary endpoint was a composite of the first sVT and SCD. The levels of urinary 8-hydroxy-2'-deoxyguanosine (U-8-OHdG), a marker of oxidative DNA damage that reflects the inflammatory activity of CS, other biomarkers, and indices of cardiac function and renal function were measured on admission.

RESULTS

Eighty-nine consecutive patients with CS were enrolled; 28 patients with no abnormal 18F-fluorodeoxyglucose (18F-FDG) accumulation in the heart were excluded and 61 patients with abnormal 18F-FDG accumulation were followed up for a median of 46 months (IQR: 20-84). During the follow-up period, 15 of 61 patients showed sVT (n=12) or SCD (n=3). A Cox proportional hazard model showed that U-8-OHdG concentration and presence of ventricular aneurysm (VA) were independent predictors of first sVT/SCD. The cut-off U-8-OHdG concentration for predicting first sVT/SCD was 14.9 ng/mg·Cr. Patients with U-8-OHdG concentration ≥14.9 ng/mg·Cr and VA showed a significantly increased risk of sVT/SCD.

CONCLUSIONS

U-8-OHdG and presence of VA were powerful predictors of first sVT/SCD in patients with CS, facilitating the stratification of cardiac events and providing relevant information about the substrates of ventricular tachycardia.

Biodegradable, Breathable Leaf Vein-Based Tactile Sensors with Tunable Sensitivity and Sensing Range

Resistive pressure sensors have been widely studied for application in flexible wearable devices due to their outstanding pressure-sensitive characteristics. In addition to the outstanding electrical performance, environmental friendliness, breathability, and wearable comfortability also deserve more attention. Here, a biodegradable, breathable multilayer pressure sensor based piezoresistive effect is presented. This pressure sensor is designed with all biodegradable materials, which show excellent biodegradability and breathability with a three-dimensional porous hierarchical structure. Moreover, due to the multilayer structure, the contact area of the pressure sensitive layers is greatly increased and the loading pressure can be distributed to each layer, so the pressure sensor shows excellent pressure-sensitive characteristics over a wide pressure sensing range (0.03-11.60 kPa) with a high sensitivity (6.33 kPa^-1 ). Furthermore, the sensor is used as a human health monitoring equipment to monitor the human physiological signals and main joint movements, as well as be developed to detect different levels of pressure and further integrated into arrays for pressure imaging and a flexible musical keyboard. Considering the simple manufacturing process, the low cost, and the excellent performance, leaf vein-based pressure sensors provide a good concept for environmentally friendly wearable devices.

Predicting risk of sudden cardiac death in patients with cardiac sarcoidosis using multimodality imaging and personalized heart modeling in a multivariable classifier

Cardiac sarcoidosis (CS), an inflammatory disease characterized by formation of granulomas in the heart, is associated with high risk of sudden cardiac death (SCD) from ventricular arrhythmias. Current "one-size-fits-all" guidelines for SCD risk assessment in CS result in insufficient appropriate primary prevention. Here, we present a two-step precision risk prediction technology for patients with CS. First, a patient's arrhythmogenic propensity arising from heterogeneous CS-induced ventricular remodeling is assessed using a novel personalized magnetic-resonance imaging and positron-emission tomography fusion mechanistic model. The resulting simulations of arrhythmogenesis are fed, together with a set of imaging and clinical biomarkers, into a supervised classifier. In a retrospective study of 45 patients, the technology achieved testing results of 60% sensitivity [95% confidence interval (CI): 57-63%], 72% specificity [95% CI: 70-74%], and 0.754 area under the receiver operating characteristic curve [95% CI: 0.710-0.797]. It outperformed clinical metrics, highlighting its potential to transform CS risk stratification.

Cardiac sarcoidosis: Two case reports

The clinical presentation of cardiac sarcoidosis is variable. We report two cases of cardiac sarcoidosis to highlight the varied clinical presentations and diagnostic challenges in our setting, and encourage the consideration of sarcoidosis as a differential in unexplained arrhythmias and heart failure.