1 Division of Pediatric Cardiology, Department of Pediatrics, Stanford University School of Medicine, Lucile Packard Children's Hospital, Stanford, California, USA.
2 Division of Cardiology, Department of Medicine, London Health Sciences Centre, Western University, London, Ontario, Canada. Electronic address: zachary.singer@lhsc.on.ca.
3 Division of Cardiac Surgery, Institut Universitaire de Cardiologie, et de Pneumologie, de Québec, Laval University, Québec City, Québec, Canada.
4 Division of Cardiology and Critical Care Medicine, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Laval University, Québec City, Québec, Canada.