BEST ORAL ABSTRACTS1575Extracellular volume associates with outcomes more strongly than native or post-contrast myocardial T11507Cardiac Magnetic Resonance measured Extracellular Volume Independently Predicts Adverse Outcome in Heart Failure with Preserved Ejection Fraction1457Cardiac MRI Under Percussive Ventilation: A New Promising Technique1644Histological Validation of Cardiac Magnetic Resonance for the Evaluation of Myocardial Fibrosis after Heart Transplantation in Children1493First Pass Perfusion Reserve Index in Paediatric Patients with Arterial Switch for Transposition of Great Arteries1652Myocardial Fibrosis is Prevalent in Obstructive Sleep Apnea and Associated with Hospitalization for Heart Failure or Death