[1] Univ Florence, Sch Med, Vasc Surg, Dept Cardiothorac & Vasc Surg,Careggi Univ,Teachi, Largo Brambilla 3, I-50134 Florence, Italy
[2] Univ Insubria, Sch Med, Vasc Surg, Dept Surg & Morphol Sci,Circolo Univ,Teaching Hos, Varese, Italy
[3] Univ Messina, Sch Med, Vasc Surg, Dept Cardiovasc & Thorac Sci,G Martino Univ Teach, Messina, Italy