Arrhythmia in Cardiac Sarcoidosis

Abstract

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

An mTORC1‐Dependent Mouse Model for Cardiac Sarcoidosis

“…A high proportion of sarcoidosis‐related hospitalizations—one‐fifth reported in 1 population study 23 —involve patients who suffer from arrhythmias, and there are many overlaps in clinical presentation between cardiac sarcoidosis patients and patients with ACM, including a higher risk for sudden cardiac death. 24 , 25 Therefore, we analyzed the expression and distribution of the desmosomal protein plakoglobin and connexin 43, the main protein in cardiac ventricular gap junctions. The housekeeping protein N‐Cadherin was used as a tissue quality control, and its expression levels and distribution pattern were similar between controls and TSC2 KO animals.…”

Arrhythmias in Cardiac Sarcoidosis: Management and Prognostic Implications

“… Those with persistent severe LV systolic dysfunction (LVEF < 35%) despite optimal medical therapy and immunosuppression, if active inflammation is demonstrated, are candidates for ICD implantation for primary prevention (class I). Expert opinion suggests proceeding with ICD implantation without a waiting period in those with severely depressed EF of less than 25% due to low likelihood of EF recovery [ 69 , 70 ]. Patients with mild to moderate LV systolic dysfunction (35 < EF < 50%) and concomitant RV dysfunction with RV EF < 40%, despite optimal medical therapy and immunosuppression, if active inflammation is demonstrated, might be considered for ICD (class IIb).…”

“…Those with persistent severe LV systolic dysfunction (LVEF < 35%) despite optimal medical therapy and immunosuppression, if active inflammation is demonstrated, are candidates for ICD implantation for primary prevention (class I). Expert opinion suggests proceeding with ICD implantation without a waiting period in those with severely depressed EF of less than 25% due to low likelihood of EF recovery [69,70]. 4.…”

Cardiac Sarcoidosis: A Comprehensive Clinical Review

“…Isolated CS is a more serious disease than CS associated with extracardiac sarcoidosis [ 11 , 32 ]. Cardiac manifestations of CS include ventricular and atrial arrhythmias, AV or intraventricular conduction disturbance, sinus node dysfunction, heart failure, sudden cardiac death (SCD) and less commonly valvular heart disease, ischemia, pericardial disease with or without pericardial effusion.…”

“…The most common symptoms of CS related to these cardiac manifestations are palpitation, presyncope, syncope, breathlessness disproportionate to the extent of pulmonary involvement, angina-like chest pain, edema or cardiac arrest, sudden cardiac death as a first presentation of the disease. Approximately 20–25% of patients with CS are asymptomatic [ 9 , 32 ]. The manifestations of CS mainly depend on the location and extent of granulomas and fibrosis.…”