ABSTRACT

BACKGROUND- Transcatheter aortic valve replacement (TAVR) has emerged as a safe and effective therapeutic option for patients with severe aortic stenosis (AS) who are at prohibitive, high, or intermediate risk for surgical aortic valve replacement (SAVR). However, in low-risk patients, SAVR remains the standard therapy in current clinical practice.

OBJECTIVES - This study sought to perform a meta-analysis of randomized controlled trials (RCTs) comparing TAVR versus SAVR in low-risk patients.

METHODS - Electronic databases were searched from inception to March 20, 2019. RCTs comparing TAVR versus SAVR in low-risk patients (Society of Thoracic Surgeons Predicted Risk of Mortality [STS-PROM] score <4%) were included. Primary outcome was all-cause death at 1 year. Random-effects models were used to calculate pooled risk ratio (RR) and corresponding 95% confidence interval (CI).

RESULTS- The meta-analysis included 4 RCTs that randomized 2,887 patients (1,497 to TAVR and 1,390 to SAVR). The mean age of patients was 75.4 years, and the mean STS-PROM score was 2.3%. Compared with SAVR, TAVR was associated with significantly lower risk of all-cause death (2.1% vs. 3.5%; RR: 0.61; 95% CI: 0.39 to 0.96; p = 0.03; I2 = 0%) and cardiovascular death (1.6% vs. 2.9%; RR: 0.55; 95% CI: 0.33 to 0.90; p = 0.02; I2 = 0%) at 1 year. Rates of new/worsening atrial fibrillation, life-threatening/disabling bleeding, and acute kidney injury stage 2/3 were lower, whereas those of permanent pacemaker implantation and moderate/severe paravalvular leak were higher after TAVR versus SAVR. There were no significant differences between TAVR versus SAVR for major vascular complications, endocarditis, aortic valve re-intervention, and New York Heart Association functional class ≥II.

CONCLUSIONS- In this meta-analysis of RCTs comparing TAVR versus SAVR in low-risk patients, TAVR was associated with significantly lower risk of all-cause death and cardiovascular death at 1 year. These findings suggest that TAVR may be the preferred option over SAVR in low-risk patients with severe AS who are candidates for bioprosthetic AVR.