Biological or mechanical prostheses in tricuspid position? A meta-analysis of intra-institutional results

Background Tricuspid valve replacement (TVR) is an uncommon procedure. The use of biological vs mechanical prostheses in TVR has pros and cons. Therefore, we debate the choice between the different types of valves by means of a meta-analysis of studies of the last decade. Methods The heading "tricuspid valve replacement and (bio* or mec*)" was used to retrieve studies from Medline, Current Contents, and Embase. Eight out of 11 studies met the preset strict criteria: intra-institutional comparison of results of biological or mechanical TVR. Survival of hospital-discharged patients was recalculated to reduce the effect of unbalanced perioperative risk factors on overall survival. Hazard ratio was obtained from actuarial survival graphics comparison and at-risk groups, according to the method described by Parmar . If missing, the number of patients at risk was approximated assuming constant and noninformative censoring. Hazard pooling was done according to study heterogeneity. Bioprostheses were assumed as the gold standard and mechanical prostheses assumed as the challenging device. Therefore, a hazard more than 1 pointed to a higher risk of mechanical prostheses. Our 1998 study was updated for this analysis. Results In this study, 1,160 prostheses and 6,046 follow-up years were analyzed. The pooled survival hazard ratio of mechanical prostheses versus bioprostheses was 1.07 (0.84 to 1.35, p = 0.60). The pooled freedom from reoperation hazard ratio was 1.24 (0.67 to 2.31, p = 0.67). Pooled survival differences were trivial, favoring mechanical prostheses at 1 (-0.04%) and 15 years (-1.1%) and favoring bioprostheses (+1.8%) at 10 years. Conclusions There is not a gold standard in tricuspid prostheses replacement. Prosthetic choice is left to the surgeon's clinical judgment, taking into consideration each patient's characteristics and needs. © 2004 by The Society of Thoracic Surgeons.