Risk stratification of patients with Brugada syndrome: the impact of myocardial strain analysis using cardiac magnetic resonance feature tracking

Objective: This study evaluated the prognostic significance of cardiac magnetic resonance myocardial feature tracking (CMR-FT) in patients with Brugada syndrome (BrS) to detect subclinical alterations and predict major adverse events (MAE). Methods: CMR was performed in 106 patients with BrS and 25 healthy controls. Biventricular global strain analysis was assessed using CMR-FT. Patients were followed over a median of 11.6 [8.8 +/- 13.8] years. Results: The study cohort was subdivided according to the presence of a spontaneous type 1 ECG (sECG) into sBrS (BrS with sECG, n = 34 (32.1%)) and diBrS (BrS with drug-induced type 1 ECG, n = 72 (67.9%)). CMR-FT revealed morphological differences between sBrS and diBrS patients with regard to right ventricular (RV) strain (circumferential (%) (sBrS-7.9 +/- 2.9 vs diBrS -9.5 +/- 3.1, p = 0.02) and radial (%) (sBrS 12.0 +/- 4.3 vs diBrS 15.4 +/- 5.4, p = 0.004)). During follow-up, MAE occurred in 11 patients (10.4%). Multivariable analysis was performed to identify independent pre-dictors for the occurrence of events during follow-up. The strongest predictive value was found for RV circumferential strain (OR 3.2 (95% CI 1.4 -6.9), p = 0.02) and RVOT/BSA (OR 3.1 (95% CI 1.0 -7.0), p = 0.03). Conclusions: Myocardial strain analysis detected early subclinical alterations, prior to apparent changes in myocardial function, in patients with BrS. While usual functional parameters were within the normal range, CMR-FT revealed pathological results in patients with an sECG. Moreover, RV circumferential strain and RVOT size provided additional prognostic information on the occurrence of MAE during follow-up, which reflects electrical vulnerability. (c) 2021 Hellenic Society of Cardiology. Publishing services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).