Cardiac MRI Imaging Protocol

All CMR scans were performed on a 3-Tesla scanner (Siemens Skyra, Erlangen, Germany) with an 18-channel cardiac coil as previously detailed [7 (link), 10 (link)]. Retrospective ECG gating was nominally used for image acquisition. In cases of arrhythmia, prospective gating was employed. In brief, the protocol comprised: standard long- and short-axis cine imaging; basal, mid-ventricular and apical short-axis T1 mapping pre- and post-contrast and late gadolinium enhancement (LGE) imaging at least 10 min after the final injection of contrast (Gadovist, Bayer Healthcare, Germany-total dose 0.15 mmol/kg). All cine images were acquired using balanced steady state free precession (SSFP) sequences and the following parameters: slice thickness 8 mm; distance factor 25%; image matrix 256 × 204 and segments amended according to heart rate ( < 70 b.p.m = 15 segments; 70–80 b.p.m = 12 segments; 80–100 b.p.m = 11 segments).