At the Mediterranean Hospital of Athens, Prof. Mauro Cassese undertook proctoring in the use of Symetis valve systems and aortic valve replacement through right side mini-thoracotomy. Increasing the skills of cardiac surgeons around the world is one of the missions of Prof. Cassese, always at the service of colleagues and patients, to ensure excellent performance. Every year, his scientific research and training includes dozens of proctoring sessions on every continent and, in so doing, he has launched hundreds of surgeons along the path of new techniques in minimally invasive and nano-invasive valve replacement.