ObjectiveTo compare the outcomes of mechanical prosthetic versus bioprosthetic replacement of tricuspid valve. Methods We retrospectively analyzed the clinical data of 344 patients underwent tricuspid valve replacement (TVR) in Guangdong General Hospital between January 2000 and December 2010. There were 227 female and 117 male patients with their age of 8-74 (42.0±13.3) years. We allocated the patients into two groups: 168 patients (48.8%) at age of 37.0±11.6 years underwent mechanical tricuspid valve replacement (the MTVR group) and 176 (51.2%) patients at age of 46.0±13.4 years underwent biological tricuspid valve replacement (the BTVR group). Follow-up data were obtained via patients' visiting the outpatient clinic, telephone or mail contacts. ResultsThe mean follow-up time was 5.7 years (ranged from 2 months to 12.6 years). In the BTVR group, 149 patients survived to discharge from hospital, and 144 patients were followed-up successfully, giving a 96.6% follow-up rate. Early mortality (within 30 days post-operation) occurred in 29 patients (16.5%), and 14 patients (7.9%) died after 30 days post-operation. Eighteen bioprosthetic valve degeneration was found during follow-up, and infective endocarditis in 3 patients. In the MTVR group, 152 patients survived to discharge from hospital, 142 patients (93.4%) were followed-up. Early mortality in 13 patients (7.7%), and 14 patients (8.3%) died after 30 days post-operation. Nineteen patients suffered from mechanical prosthesis obstruction, no infective endocarditis patients was found in the MTVR group. There was no statistical difference between the BTVR group and the MTVR group in mortality rate (24.4% versus 16.1%, P=0.054) and in reoperation rate (4.2% versus 9.9%, P=0.051), respectively．There were statistical differences in long-term survival rates between the BTVR group and the MTVR group with 1 year survival rate(78% vs. 89%), 5 years survival rate(74% vs. 86%), and 10 years survival rate (66% versus 78%) with P value at 0.003. ConclusionsThis study suggests that the type of implanted prosthesis in tricuspid replacement does not affect long-term outcomes or the reoperation rate. The survival rate is higher in the MTVR group than that in the BTVR group, which may contribute to younger age in the MTVR group. There is a tendency in higher infective endocarditis incidence in the BTVR group than that in the MTVR group.