1. Cardiovascular Center, Azienda Sanitaria-Universitaria Integrata of Trieste, Trieste, Italy
2. Department of Cardiology, Villa Bianca Hospital, Trento, Italy
3. Department of Cardiology, Azienda Sanitaria-Universitaria Integrata of Trieste, Trieste, Italy
4. Department of Statistics, University of Trieste, Trieste, Italy