Structural valve deterioration after transcatheter aortic valve implantation

BACKGROUND: Transcatheter aortic valve implantation (TAVI), widely used to treat high-risk patients with severe symptomatic aortic stenosis, has recently been extended to younger patients at lower operative risk in whom long-term durability of TAVI devices is an important concern. Therefore, we conducted a systematic review and meta-analysis of observational studies addressing the frequency of structural valve deterioration (SVD) after TAVI. METHODS: We searched Medline, Embase, Cochrane Database of Systematic Reviews, and Cochrane CENTRAL from 2002 to September 2016. We included observational studies following patients with TAVI for at least 2 years. Independently and in duplicate, we evaluated study eligibility, extracted data, and assessed risk of bias for SVD post-TAVI. Our review used the GRADE system to assess quality of evidence. We pooled incidence rates using a random effects model. RESULTS: Thirteen studies including 8914 patients, with a median follow-up between 1.6 and 5 years, reported an incidence of SVD post-TAVI between 0 to 1.34 per 100 patient years. The pooled incidence of SVD was 28.08 per 10 000 patients/year (95% CI 2.46 to 73.44 per 100 patient years). Of those who developed SVD, 12% underwent valve re-intervention. Confidence in the evidence was moderate due to inconsistency among studies. CONCLUSION: Structural valve deterioration is probably an infrequent event within the first 5 years after TAVI. Ascertaining the impact of SVD and the need for valve-related re-interventions to inform recommendations for patients with a longer life-expectancy will require studies including a large number of patients with longer follow-up (>10 years).