From the Guidelines
Non-caseating granulomas are a hallmark of cardiac sarcoidosis, and their presence puts patients at risk of developing both atrioventricular (AV) block and ventricular arrhythmias (VA), particularly in the presence of left ventricular (LV) dysfunction. The management of non-caseating granulomas in cardiac sarcoidosis involves a multidisciplinary approach, including the use of immunosuppression, cardiac pacing, and implantable cardioverter-defibrillators (ICDs) 1.
Key Considerations
- The presence of myocardial noncaseating granulomas and inflammation increases the risk of AV block and VA, especially with LV dysfunction 1.
- ICD implantation is recommended in patients with cardiac sarcoidosis presenting with syncope and documented spontaneous sustained VA 1.
- Immunosuppression can result in transient reversal of AV block, but the reversibility is unpredictable, and pacing should be performed according to the most recent guidelines 1.
- EPS is reasonable in patients with cardiac sarcoidosis and syncope of suspected arrhythmic etiology to identify patients at risk of having VA 1.
Treatment Approach
- ICD implantation is reasonable in patients with cardiac sarcoidosis and syncope of suspected arrhythmic origin, particularly with LV dysfunction or pacing indication 1.
- Immunosuppression, such as corticosteroids, may be used to manage symptomatic disease, but its effectiveness in preventing VA is controversial 1.
- Cardiac pacing should be performed according to the most recent guidelines for patients with conduction abnormalities 1.
- Management should address both the underlying condition and any organ dysfunction resulting from granulomatous inflammation 1.
From the Research
Definition and Characteristics
- Non-caseating granulomas are a type of granulomatous inflammation characterized by the presence of granulomas without caseous necrosis 2.
- They are a hallmark of sarcoidosis, a systemic disease of unknown etiology that can affect any organ, but most commonly manifests in the lungs and intrathoracic lymph nodes 2.
Clinical Implications
- Non-caseating granulomas can be found in various conditions, including sarcoidosis, Crohn's disease, and metastatic Crohn's disease 3, 4.
- In patients with ileal pouches, non-caseating granulomas on histology may indicate clinical or histologic Crohn's disease of the pouch, but one-third of patients may not develop clinical Crohn's disease 3.
- Ocular sarcoidosis can present with non-caseating granulomas and may require treatment with corticosteroids, immunosuppressants, or biologic agents such as adalimumab 5.
Treatment and Management
- Treatment of non-caseating granulomas depends on the underlying condition and may involve corticosteroids, immunosuppressants, or biologic agents such as infliximab 2, 5, 6.
- Infliximab has been shown to be effective in treating refractory neurosarcoidosis, but relapses can occur during follow-up 6.
- Metastatic Crohn's disease, which can present with non-caseating granulomas, often requires unsatisfactory treatment, and randomized controlled trials are lacking 4.