Impact of prosthesis-patient mismatch on survival after mitral valve replacement： a systematic review

Objective To determine whether the prosthesis-patient mismatch has a deleterious impact on survival after mitral valve replacement.Data sources A comprehensive literature search of PubMed,Embase,and ScienceDirect was carried out.References and cited papers of relevant articles were also checked.Study selection All articles published after January 1980 was initially considered.Non-English and non-human studies,case reports,and reviews were excluded from the initial search.References and cited papers of relevant articles were also checked.Results A total of 8 retrospective cohort studies were identified for this review.The overall incidence of prosthesis-patient mismatch （〈1.3 to 〈1.2 cm2/m2） after mitral valve replacement ranged from 3.7% to 85.9% （moderate prosthesis-patient mismatch （0.9 to 1.2 cm2/m2） in 37.4% to 69.5%,severe prosthesis-patient mismatch （〈0.9 cm2/m2） in 8.7% to 16.4%）.Four studies demonstrated an association of prosthesis-patient mismatch with reduced long-term survival,but the other four studies found no significant deleterious impact of prosthesis-patient mismatch after mitral valve replacement.No definite conclusion could be derived from these conflicting results.Conclusions Current evidence is insufficient to derive a definite conclusion whether mitral prosthesis-patient mismatch affects long-term survival because of the biases and confounding factors that interfere with late clinical outcomes.Good-quality prospective studies are warranted to evaluate the impact of mitral prosthesis-patient mismatch after mitral valve replacement in the future.

Transcatheter aortic valve implantation versus surgical aortic valve replacement for severe aortic stenosis： a meta analysis

Background Transcatheter aortic valve implantation （TAVI） has emerged as the treatment choice for non-operable patients with severe symptomatic aortic stenosis （AS） and may be a good alternative to surgery for those at very high or prohibitive surgical risk. We performed a meta-analysis to evaluate the comparative benefits of TAVI versus surgical aortic valve replacement （SAVR） in patients with severe AS. Methods A comprehensive literature search of PubMed, Embase, ScienceDirect and Cochrane Central Register of Codtrolled trials was performed, and randomized trials as well as cohort studies with propensity score analysis were included. Results One randomized trial （n=699） and six retrospective cohort studies （n=781） were selected for meta-analysis. Mortality at 30-day and 1-year follow-up was comparable between TAVI and SAVR. Despite similar incidences of stroke, myocardial infarction, re-operation for bleeding, and renal failure requiring dialysis, TAVI was associated with a lower occurrence rate of new-onset atrial fibrillation （OR 0.51,95% CI 0.33-0.78） and shorter procedural time （mean difference -67.50 minutes, 95% CI -87.20 to -47.81 minutes）. Post-operative aortic regurgitation and permanent pacemaker implantation were more common in patients after TAVI than in those with SAVR （OR 5.53, 95% CI 3.41-8.97; OR 1.71, 95% CI 1.02-2.84, respectively）. Conclusion In patients with severe symptomatic AS, TAVI and SAVR did not differ with respect to short- and mid-term survival, but the incidence of permanent pacemaker implantation and post-procedural aortic regurgitation remain relatively high after TAVI.