Mechanical Versus Bioprosthetic Valve Replacement in the Tricuspid Valve Position: A Systematic Review and Meta-Analysis

Background The ideal prosthesis for tricuspid valve replacement (TVR) continues to be debated. There are few published data comparing mechanical and bioprosthetic valves, and all are retrospective studies with relatively small sample sizes. Aim This study was conducted to compare mechanical and bioprosthetic valves for TVR. Method A literature search of six databases (PubMed, EMBASE, Ovid, ScienceDirect, JSTOR, and Wiley Blackwell's online library) was performed with the keywords "tricuspid valve disease, tricuspid valve replacement and (bioprosthetic or mechanical)". Primary outcomes were hospital mortality, long-term survival, tricuspid valve reoperation, valve failure, thrombosis, and thrombo-embolism. Risk ratio (RR) was used to compare dichotomous parameters and time-to-event outcomes. "Survival and re-interventions" were pooled using a meta-analysis of hazard ratios (HR). Publication bias was accessed using a funnel plot. Results A total of 23 retrospective studies involving 945 mechanical and 1,332 biological tricuspid prostheses were included. The studies were published between January 2002 and September 2019. Hospital mortality (30-day mortality) did not differ between groups (RR, 0.83; 95% confidence interval [CI], 0.66-1.05; p=0.12). Long-term survival was evaluated in 15 studies, and it was not significantly different between patients with mechanical compared with those with bioprosthetic valves (pooled HR, 0.97; 95% CI, 0.61-1.54; p=0.88). Freedom from tricuspid valve reoperation was assessed in eight studies, and no difference was found between the groups (pooled HR, 1.03; 95% CI, 0.63-1.69; p=0.89). Valve failure in the 5-year postoperative period was evaluated by seven studies, and there was no statistically significant difference between the two groups (pooled RR, 1.33; 95% CI, 0.42-4.27; p=0.63). Conclusions The results of this meta-analysis suggest an equal risk of 30-day and late mortality, reoperation, and 5-year valve failure in patients with mechanical versus biological TVR. The choice of the prosthesis in the tricuspid position should depend mainly on the patient's risk factors and no superiority of one prosthesis over the other in this position.