Heart valve sizing and clinical outcomes in patients undergoing transcatheter aortic valve implantation

Objectives: To investigate the impact of transcatheter heart valve (THV) sizing on procedural results and clinical outcomes following transcatheter aortic valve implantation (TAVI).

Background: The impact of individual THV sizing for patients with borderline aortic annulus anatomy remains unclear.

Methods: In the prospective BernTAVI registry, THV sizing conditions were retrospectively evaluated, and patients were categorized into three groups based on the recommendations and the sizing chart of the manufacturers: optimal sizing, borderline sizing (THV size located within 5% to each border of the optimal sizing recommendation), and suboptimal sizing (THV size outside the recommended range). The latter two groups were further subcategorized into THV-oversizing and THV-undersizing. The primary endpoint was a composite of all-cause death and unplanned repeat intervention at 1 year.

Results: Out of a total of 1,638 patients who underwent TAVI, 9.5 and 15.6% of patients were categorized into the borderline and suboptimal sizing group, respectively. Device success was achieved in 87.4, 88.9, and 83.6% of patients with optimal, borderline, and suboptimal sizing, respectively. The primary endpoint occurred in 12.3% of patients with optimal sizing, 14.9% of patients with borderline sizing (HR_adj 1.35, 95%CI 0.87-2.09), and in 17.4% of patients with suboptimal sizing (HR_adj 1.42, 95%CI 1.01-1.99). Within the suboptimal sizing cohort, unfavorable outcomes were mainly associated with THV undersizing (device success: 76.4%, primary endpoint: 23.9%, HR_adj 1.98, 95%CI 1.36-2.87).

Conclusion: Suboptimal TAVI prosthesis sizing is associated with an increased risk of all-cause death and unplanned repeat intervention within 1 year largely attributable to undersized THV prostheses.