Capability of three-dimensional speckle tracking radial strain for identification of patients with cardiac sarcoidosis

Since cardiac sarcoidosis (CS) leads to substantial morbidity and sudden death, early diagnosis and appropriate management are crucial for patients with CS. Echocardiography used to be considered a useful diagnostic tool for patients with CS, but CS may clinically present as dilated cardiomyopathy (DCM). Our objective was to investigate whether a novel three-dimensional (3-D) speckle-tracking strain can identify patients with CS more accurately. We studied 23 CS patients with an ejection fraction (EF) of 46 ± 10 %, and 16 EF-matched patients with DCM (EF 45 ± 11 %). Global radial (GRS), circumferential (GCS) and longitudinal (GLS) strain was assessed using 3-D speckle-tracking system. GRS of patients with CS was significantly lower than that of patients with DCM (18.5 ± 8.4 vs. 28.5 ± 8.3 %, p < 0.01), but GCS and GLS in patients with CS and DCM were similar. GRS ≦ 21.1 could differentiate CS from DCM with a sensitivity of 70 %, specificity of 88 % and area under the curve of 0.79. An additional noteworthy findings was that, patients with CS showed more negative radial strain curves than did those with DCM (1.7 ± 2.3 vs. 0.1 ± 0.5, p < 0.01). In conclusion, 3-D speckle-tracking radial strain shows good potential to distinguish CS from DCM. Our observations can thus be expected to have clinical implications for management of CS patients.