1 Department of Paediatric and Congenital Cardiac Surgery and Cardiology, Azienda Ospedaliero Universitaria, Ospedali Riuniti Ancona (Umberto I, GM Lancisi, G Salesi), Ancona, Italy.
2 Department of Cardiothoracic and Vascular Surgery, Kenyatta National Hospital and University of Nairobi, Nairobi, Kenya.