After graduating in Medicine and Surgery at the University of Turin and specialising in Cardiac Surgery at the University of Genoa, he has been working as a cardiac surgeon at the European Hospital in Rome and, since 2024, as an Associate Professor of Cardiac Surgery at the Saint Camillus International University for Health Sciences.

For more than fifteen years he has coordinated the clinical and technological trials laboratory at the European Hospital and has published more than 120 international papers, some of which have become part of international guidelines in the reference fields.

Peer reviewer and associate editor for several scientific journals in the field, Professor Weltert is editor of the European guidelines for Patient Blood Management, as well as an expert in coronary beating heart surgery, VEST external support for saphenous vein bypasses, mitral surgery, minimally invasive replacement and repair surgery of the ascending aorta and aortic valve, and transcatheter aortic valve implantation (TAVI).

In his spare time he enjoys sailing and flying aeroplanes.