From the Guidelines
An electrocardiogram (EKG) can detect abnormalities associated with cardiac sarcoidosis but cannot definitively diagnose the condition on its own. EKG findings in cardiac sarcoidosis may include conduction disturbances such as bundle branch blocks, atrioventricular blocks, ventricular arrhythmias, or nonspecific ST-segment and T-wave changes. However, these findings are not specific to sarcoidosis and can occur in many other cardiac conditions. For a definitive diagnosis of cardiac sarcoidosis, additional testing is necessary, including cardiac MRI with gadolinium enhancement, PET scans, or in some cases, endomyocardial biopsy.
Key Points to Consider
- The sensitivity of EKG in detecting cardiac sarcoidosis is limited, with a combined sensitivity of ECG plus echocardiography being only 32% 1.
- EKG is valuable as an initial screening tool and for monitoring cardiac involvement in patients with known sarcoidosis, but its limitations stem from the patchy nature of sarcoid granulomas in the heart, which may not always cause detectable electrical abnormalities.
- Patients with suspected cardiac sarcoidosis should undergo comprehensive cardiac evaluation beyond just an EKG, especially if they have symptoms like palpitations, syncope, or heart failure.
- Baseline ECG is recommended to identify patients who may warrant additional evaluation, given its availability, non-invasiveness, harmlessness, and relatively low cost 1.
Diagnostic Approach
- Cardiac MRI with late gadolinium enhancement has emerged as a valuable imaging tool for the diagnosis of cardiac involvement in sarcoidosis 1.
- Positron emission tomography imaging with fluorodeoxyglucose can also identify inflammation and has better diagnostic accuracy than older techniques 1.
Management Considerations
- Immune-modulating therapy can be useful to treat sarcoidosis, and ICD implantation is reasonable for patients with cardiac sarcoidosis 1.
- The prognosis of patients with symptomatic cardiac sarcoidosis is variable, with important predictors of mortality including LV end-diastolic diameter, NHYA functional class, and sustained ventricular tachycardia 1.
From the Research
Detection of Cardiac Sarcoidosis using EKG
- An electrocardiogram (EKG) can be a valuable tool for screening cardiac involvement in patients with sarcoidosis 2.
- Several EKG parameters have been associated with cardiac involvement in sarcoidosis, including:
- Higher-degree atrioventricular (AV) block
- QRS complex fragmentation and widening
- Certain T wave abnormalities
- These EKG findings may indicate cardiac involvement and guide further diagnosis 2.
- However, it is essential to note that EKG is not a definitive diagnostic tool for cardiac sarcoidosis, and other imaging modalities like cardiac magnetic resonance imaging (MRI) and positron emission tomography (PET) may be necessary for confirmation 3, 4, 5, 6.
- The use of EKG as a screening tool can help identify patients who may require further evaluation and treatment, potentially improving outcomes for those with cardiac sarcoidosis 2.