4088Diagnostic specificity of triangular basal inferoseptal late gadolinium enhancement for identification of cardiac sarcoidosis
Authors: Kuo L , Yuchi Han Y.C.,H , David Mui D M , Ying Zhang Y Z , Robert D Schaller R S , David S Frankel D F , Francis E Marchlinski F M , Benoit Desjardins B D , Saman Nazarian S N 
Published: October 2019

Abstract

Background/Introduction
Sarcoidosis, a multisystem disorder characterized by infiltration of noncaseating granulomas, can manifest as left ventricular (LV) dysfunction and fatal ventricular arrhythmias. The clinical diagnosis of cardiac sarcoidosis (CS) can be challenging and often requires multiple imaging modalities including cardiac magnetic resonance (CMR). The characterization of unique late gadolinium enhancement (LGE) patterns may assist in the diagnosis on CMR.

Purpose
We sought to examine the diagnostic value of inferoseptal triangular LGE for CS.

Methods
The retrospective cohort included 149 non-ischemic cardiomyopathy (NICM) patients referred to our hospital for a CMR from January 2012 to December 2018. Left ventricular LGE was identified in 86 patients (56.4±10.4 years, 84.9% male). Amongst them, 73 patients with septal LGE. We classified the various septal LGE patterns into four categories: (A) Mid-wall septal and basal inferoseptal triangular LGE; (B) Endocardial right ventricular (RV) septal LGE; (C) Basal inferoseptal triangular with endocardial RV septal LGE; (D) Mid-wall septal LGE (Figure). The diagnosis of sarcoidosis was confirmed by the Japanese Circulation Society/Japanese Society of Nuclear Cardiology guidelines.

Results
Individual diagnoses and imaging characteristics of non-ischemic cardiomyopathy types with septal LGE are summarized in the Table. LV ejection fraction, LV end-diastolic volume index (EDVI) and end-systolic volume index (ESVI) did not significantly differ between sarcoidosis and non-sarcoidosis patients. Pattern A and Pattern B were highly specific but insensitive (Specificity/Sensitivity- A: 98.4/8.3%, p=0.19; B: 95.1%/8.3%, p=0.64) for CS. The only pattern with statistically significantly diagnostic indices was pattern C: specificity of 100% and sensitivity of 58.3% (p<0.001). Pattern D revealed both low specificity of 6.6% and sensitivity of 25% (p<0.001).
Imaging characteristics and diagnosis Septal LGE/Diagnosis Sarcoidosis Idiopathic Pulmonary hypertension Giant cell myocarditis Amyloidosis Systemic lupus erythematous Myeloproliferative neoplasm Large cell lymphoma Mid-wall septal and basal inferoseptal triangular LGE 1 1 0 0 0 0 0 0 Endocardial RV septal LGE 1 2 0 1 0 0 0 0 Basal inferoseptal triangular andendocardial RV septal LGE 7 0 0 0 0 0 0 0 Mid-wall septal LGE 3 50 3 0 1 1 1 1 Individual diagnosis and patterns of septal late gadolinium enhancement.
Septal LGE patterns

Conclusions
The presence of basal inferoseptal triangular LGE pattern with endocardial RV involvement enables an accurate diagnosis of CS. The absence of this triangular septal LGE pattern, however, cannot exclude the diagnosis of CS.

Acknowledgement/Funding
Taipei Veterans General Hospital-National Yang-Ming University Excellent Physician Scientists Cultivation Program, No. 106-V-A-009