Abstract 10382: Impact of Late Gadolinium Enhancement in Differentiating Cardiac Sarcoidosis with Left Ventricular Dysfunction from Dilated Cardiomyopathy
Introduction: Differentiating between cardiac sarcoidosis (CS) and idiopathic dilated cardiomyopathy (DCM) in patients with left ventricular (LV) dysfunction is a diagnostic dilemma, and appropriate treatment may be delayed. Few studies have examined the morphological characteristics of late gadolinium enhancement (LGE) on cardiovascular magnetic resonance (CMR) in patients with CS, and the relationship between LGE and cardiac function is unknown.
Hypothesis: We wished to identify the morphological characteristics of LGE on CMR that differentiate patients with CS with LV dysfunction from those with DCM.
Methods: CMR was performed on 20 patients with histologically proven CS and 20 patients with DCM using a 1.5 T MR system. The heart was divided into 29 segments, and each was assessed for LGE morphology and distribution. Regions of interest were outlined on both LGE positive and normal myocardium, and the LGE-to-normal signal intensity (SI) ratio (SIR) was calculated. The correlation between the number of LGE-positive segments and biventricular function was assessed.
Results: LGE of the right ventricle (RV) was only observed in patients with CS (p<0.0001), and, in CS patients, the cardiac regions most commonly demonstrating LGE were the RV outflow tract and anteroseptal LV wall. LGE was found in a transmurally distributed patchy pattern or localized to the epicardial layer of the LV wall. In contrast, in patients with DCM, LGE was demonstrated a linear pattern in the middle layer of the interventricular septum. The SIR was markedly higher in patients with CS than those with DCM (5 ± 1.6 vs. 1.6 ± 0.3, p<0.0001). Additionally, the number of LGE-positive segments significantly correlated with LV end-diastolic volume index, LV end-systolic volume index, LV ejection fraction (EF) and RVEF (r=0.62, r = 0.72, r = −0.8, r = −0.67, all p<0.05) in patients with CS. No such correlations were seen in patients with DCM.
Conclusions: In patients with CS, LGE demonstrates a transmurally distributed patchy pattern or is localized to the epicardial layer including the anteroseptal LV or RV outflow regions. The extent of LGE correlates with LV dysfunction. Thus, the presence and distribution of LGE on CMR can be used to help distinguish between CS with LV dysfunction and DCM.
- © 2010 by American Heart Association, Inc.