Reoperations for acute prosthetic thrombosis and pannus: an assessment of rates, relationship and risk. - Rizzoli,G.; Guglielmi,C.; Toscano,G.; Pistorio,V.; Vendramin,I.; Bottio,T.; Thoene,G.; Casarotto,D. (Eur J Cardiothorac Surg, 1999)