This study aimed to investigate the rate of severe structural valve deterioration (SVD) and long-term outcomes of patients with severe symptomatic aortic stenosis undergoing transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (SAVR). Propensity score matched analysis of patients who underwent TAVI (n = 216) and SAVR (n = 216) between 2008 and 2012. Long-term echocardiographic parameters and clinical outcomes were assessed after more than 6 years after TAVI/SAVR. Rate of severe SVD was 10.5% versus 4.5% in the TAVI and SAVR groups, respectively, but the difference was not statistically significant (hazard ratio [HR] 2.5; 95% confidence interval [CI] 0.7 to 8.3; p = 0.159). This was largely driven by higher rates of mean transprosthetic gradient ≥40 mm Hg (7.0 vs 3.4%; p = 0.327) and aortic regurgitation (4.7% vs 0%; p = 0.058). TAVI patients had lower survival rates at 6 years than SAVR patients (40.7% vs 59.6%, respectively, p <0.001, HR 2.15; 95% CI 1.45 to 3.20). Rate of cardiovascular events (14.4% TAVI vs 18.2% SAVR, HR 0.8; 95% CI 0.4 to 1.3; p = 0.347) and permanent pacemaker implantation (PPI; 16.0% TAVI vs 9.2% SAVR, p = 0.234) was similar between the 2 groups. In conclusion, incidence of moderate and severe SVD was not statistically different between TAVI and SAVR. Rate of moderate or severe aortic regurgitation was significantly higher in the TAVI group with predominant use of first-generation valves. Reintervention rate was low in both groups. Survival rate was lower after TAVI, probably because of higher frailty index, but incidence of cardiovascular events, PPI, and SVD was similar in both groups.