Transcatheter versus surgical aortic valve replacement in low-risk patients for the treatment of severe aortic stenosis

Recently, two randomized trials, the PARTNER 3 and the Evolut Low Risk Trial, independently demonstrated that transcatheter aortic valve replacement (TAVR) is non-inferior to surgical aortic valve replacement (SAVR) for the treatment of severe aortic stenosis in patients at low surgical risk, paving the way to a progressive extension of clinical indications to TAVR. We designed a meta-analysis to compare TAVR versus SAVR in patients with severe aortic stenosis at low surgical risk. The study protocol was registered in PROSPERO (CRD42019131125). Randomized studies comparing one-year outcomes of TAVR or SAVR were searched for within Medline, Scholar and Scopus electronic databases. A total of three randomized studies were selected, including nearly 3000 patients. After one year, the risk of cardiovascular death was significantly lower with TAVR compared to SAVR (Risk Ratio (RR) = 0.56; 95% CI 0.33–0.95; p = 0.03). Conversely, no differences were observed between the groups for one-year all-cause mortality (RR = 0.67; 95% CI 0.42–1.07; p = 0.10). Among the secondary endpoints, patients undergoing TAVR have lower risk of new-onset of atrial fibrillation compared to SAVR (RR = 0.26; 95% CI 0.17–0.39; p < 0.00001), major bleeding (RR = 0.30; 95% CI 0.14–0.65; p < 0.002) and acute kidney injury stage II or III (RR = 0.28; 95% CI 0.14– 0.58; p = 0.0005). Conversely, TAVR was associated to a higher risk of aortic regurgitation (RR = 3.96; 95% CI 1.31–11.99; p = 0.01) and permanent pacemaker implantation (RR = 3.47; 95% CI 1.33–9.07; p = 0.01) compared to SAVR. No differences were observed between the groups in the risks of stroke (RR= 0.71; 95% CI 0.41–1.25; p = 0.24), transient ischemic attack (TIA; RR = 0.98; 95% CI 0.53–1.83; p = 0.96), and MI (RR = 0.75; 95% CI 0.43–1.29; p = 0.29). In conclusion, the present meta-analysis, including three randomized studies and nearly 3000 patients with severe aortic stenosis at low surgical risk, shows that TAVR is associated with lower CV death compared to SAVR at one-year follow-up. Nevertheless, paravalvular aortic regurgitation and pacemaker implantation still represent two weak spots that should be solved.