Meta-analysis of transcatheter aortic valve implantation versus surgical aortic valve replacement in patients at low surgical risk

Aims: Although transcatheter aortic valve implantation (TAVI) is officially indicated for severe aortic stenosis (AS) patients at intermediate or higher surgical risk, the procedure is now increasingly being performed in patients who are at low surgical risk. Data on the benefit of TAVI in this patient population are limited. We therefore aimed to perform an updated meta-analysis of all published randomised controlled trials (RCTs) and propensity score-matched studies comparing TAVI versus surgical aortic valve replacement (SAVR) in patients at low surgical risk. Methods and results: We conducted a systematic review and meta-analysis of RCTs and observational studies with propensity score matching (PSM) of TAVI versus SAVR in patients who are at low surgical risk (mean STS score <4% and/or logistic EuroSCORE <10%). The primary outcome was mortality (examined at 30 days, one year and the longest available follow-up). The secondary outcomes included procedural complications. Nine studies (n=6,124) were included. TAVI was associated with a numerically, but not statistically, significant reduced mortality at 30 days (1.45% vs 2.1%, p=0.05), and similar mortality at one year (5.1% vs 5.0%, p=0.74) and a median of two years (10.8% vs 9.8%, p=0.15). For both time points, there was significant heterogeneity between RCT/PSM studies, with the former suggesting survival advantage for TAVI and the latter for SAVR. In terms of periprocedural complications, TAVI was associated with reduced risk for stroke, bleeding and renal failure and an increase in vascular complications and pacemaker implantation. Conclusions: In patients who are at low surgical risk, TAVI seems to be associated with equivalent mortality up to a median follow-up of two years compared to SAVR. More data are required before TAVI can be routinely considered as an alternative to SAVR in low-risk patients.