Systematic review and meta-analysis to compare outcomes between intermediate- and high-risk patients undergoing transcatheter aortic valve implantation.

Aims: Recent studies have reported non-inferior outcomes for transcatheter aortic valve implantation (TAVI) compared with surgical aortic valve replacement (SAVR) in intermediate-risk patients. However, a comparison of outcomes among TAVI patients depending upon the surgical risk score has not been performed in a large study. Our aim was to compare the outcomes of TAVI in low-, intermediate-, and high-risk patients, to ascertain if the morbidity and mortality is related to the patient's risk profile or the procedure itself.

Methods and results: A thorough computer-based search was performed using Ovid MEDLINE, EMBASE, Google Scholar, and PubMed databases. We included original research studies reporting data on TAVI in the low-, intermediate-, and high-risk groups. Patients in intermediate-risk group were compared to the high-risk cohort for device success, mortality, and complications. A total of 2414 patients in the intermediate-risk group were compared with 1597 high-risk patients. On meta-analysis, intermediate-risk group demonstrated similar device success [odds ratio (OR) 1.29, 95% confidence interval (CI) 0.87-1.90, I2 = 0%, P = 0.2) but a lower 30-day mortality OR 0.54, 95% CI 0.34-0.86, I2 = 49%, P = 0.009). There was no difference in the incidence of stroke (OR 1.17, 95% CI 0.80-1.71, I2 = 36%, P = 0.42) or permanent pacemaker implantation between the two groups (OR 1.04, 95% CI 0.82-1.32, I2 = 41%, P = 0.74).

Conclusion: Transcatheter aortic valve implantation in intermediate-risk patients carries a low mortality and high success. Incidence of pacemaker and stroke remains high in the lower risk group.