The publisher apologises for errors in the author affiliations. The authors Israel Valverde and Mari Nieves Velasco Forte should have affliations numbers 1, 2, and 3:
1. Division of Imaging Sciences and Biomedical Engineering, King’s College, London, UK;
2. Cardiovascular Pathology Unit, Institute of Biomedicine of Seville, IBIS, Virgen del Rocio University Hospital/CSIC/University of Seville, Sevilla, Spain;
3. Department of Congenital Heart Disease, Evelina London Children’s Hospital, Guy’s and St Thomas’ NHS Foundation Trust, London, UK;
4. Department of Pediatrics, UT Southwestern Medical Center, 1935 Medical District Drive, Dallas, TX, USA;
5. Department of Pediatric Cardiology, Leiden University Medical Center, Leiden, The Netherlands