Abstract
BACKGROUND: In patients with isolated cardiac sarcoidosis, endomyocardial biopsy is required to confirm the diagnosis. However, endomyocardial biopsy has low sensitivity due to the patchy nature of cardiac inflammation in cardiac sarcoidosis, revealing noncaseating granulomas in <25% of patients. CASE SUMMARY: A 38-year-old healthy man developed cardiac arrest while he was exercising. Cardiac sarcoidosis or arrhythmogenic right ventricular cardiomyopathy was suspected based on electrocardiogram, echocardiography, and cardiac magnetic resonance findings. Using unipolar mapping on 3-dimensional electroanatomic mapping, the tip of the biopsy catheter was visualized, allowing targeted tissue sampling from the scar area. Histopathologic analysis confirmed a diagnosis of sarcoidosis. DISCUSSION: A novel unipolar ventricular mapping technique using electroanatomic mapping may improve the diagnostic yield for clinically isolated cardiac sarcoidosis, in which the disease is solely involving the heart. TAKE-HOME MESSAGE: Unipolar mapping integrated with 3-dimensional electroanatomic mapping allows for targeted visualization of biopsy sites, which may enhance diagnostic accuracy in cases of cardiac sarcoidosis.