OBJECTIVES The aims of the study were to assess the prognostic significance of cardiac magnetic resonance myocardial feature tracking (CMR-FT) in a cohort of patients with Brugada syndrome (BrS) to detect subclinical alterations and evaluate CMR-FT predictors of major adverse events (MAE).

BACKGROUND BrS is an inherited arrhythmogenic disease with a risk of sudden cardiac death (SCD), especially in young men. The presence of a spontaneous type 1 ECG (sECG) is known as predictor for arrhythmogenic events, but risk stratification still remains a demanding task. BrS has been considered as a primary electrical disease in the absence of structural changes. However, CMR-FT may be able to detect subclinical alterations.

METHODS and RESULTS CMR was performed in 106 consecutive patients (pts) with BrS and 25 healthy controls (HC). Biventricular strain analysis was assessed using FT. Pts were followed for a mean of 11.1 ± 3.5 years.

The study cohort was subdivided and analyzed according to the presence of a sECG, into spontaneous ,s’ (34 (32.1%)) and drug-induced ,di’ (72 (67.9%)). Pts with BrS and sECG revealed both a reduced left and right ventricular ejection fraction within the normal range compared to BrS- and HC. CMR-FT revealed morphological differences in right ventricular (RV) strain (circumferential (,s’ (-)7.9 ± 2.9 vs ,di’ (-)9.5 ± 3.1, p=0.02) and radial strain (,s’ 12.0 ± 4.3 vs ,di’ 15.4 ± 5.4, p<0.01)) between patients with BrS and sECG and those without. During FU, MAE (defined as ventricular tachyarrhythmia, adequate ICD therapy, syncope, cardiac death or grand mal seizure) were noted in 12 cases (11.3%). The presence of sECG revealed the strongest prediction for MAE. CMR-FT could detect reduced RV circumferential strain as another predictor for MAE.

CONCLUSION Our findings suggest that myocardial strain analysis may detect early subclinical alterations, prior to apparent changes in myocardial function, in patients with BrS. Moreover, CMR-FT derived parameters, especially right ventricular circumferential strain, provided superior prognostic information on the occurrence of major adverse events (MAE).