Mid-term impact of underfilling and overfilling of the SAPIEN 3 balloon-expandable transcatheter aortic valve implantation on mortality and valve function

Deformation in transcatheter heart valves: Clinical implications and considerations

Transcatheter aortic valve replacement (TAVR) has emerged as a preferred treatment modality for aortic stenosis, marking a significant advancement in cardiac interventions. Transcatheter heart valves (THVs) have also received approval for treating failed bioprosthetic valves and rings across aortic, mitral, tricuspid, and pulmonic positions. Unlike surgically implanted valves, which are sewn into the annulus, THVs are anchored through relative oversizing. Although THVs are designed to function optimally in a fully expanded state, they exhibit a certain degree of tolerance to underexpansion. However, significant deformation beyond this tolerance can adversely affect the valve's hemodynamics and durability, ultimately impacting patient outcomes. Such post-implantation deviations from the valve's intended three-dimensional design are influenced by a variety of physiological and anatomical factors unique to each patient and procedure, leading to underexpansion, eccentric expansion, and vertical deformation. These deformation patterns increase leaflet stress and strain, potentially causing fatigue and damage. This review article delves into the extent of THV deformation, its impact on leaflet function, hypoattenuating leaflet thickening, and structural valve degeneration. It provides an in-depth analysis of deformation specifics in different procedural contexts, including TAVR in native aortic stenosis, aortic and mitral valve-in-valve procedures, and redo-TAVR. Additionally, the review discusses strategies to mitigate THV deformation during the procedure, offering insights into potential solutions to these challenges.

Assessing Potential Risks of Future Redo Transcatheter Aortic Valve Replacement in Asian Patients

Background

In the Asian cohort, data are limited on the risk for coronary obstruction due to sinus of Valsalva (SOV) sequestration in redo transcatheter aortic valve replacement (TAVR) procedures.

Objectives

The aim of this study was to assess the potential risk for coronary obstruction in simulated redo TAVR in Asian patients.

Methods

Post-TAVR computed tomographic data from 788 patients who received balloon-expandable (BE) SAPIEN 3 transcatheter aortic valves (TAVs) and 334 patients who received self-expanding (SE) Evolut R or Evolut PRO TAVs were analyzed. The risk for coronary obstruction due to SOV sequestration in redo TAVR, defined as the TAV commissure level above the sinotubular junction (STJ) and a TAV-to-STJ distance <2.0 mm in each coronary sinus, was retrospectively evaluated.

Results

The potential risks for coronary obstruction due to SOV sequestration at 1 or both coronary arteries were identified in 52.1% of the BE TAV group and 71.3% of the SE TAV group (P < 0.001). After adjusting for multiple covariates, STJ diameter, STJ height, TAV oversizing degree by area, and implantation depth were independently associated with SOV sequestration risk in the BE TAV group, whereas STJ diameter and implantation depth were independently associated with SOV sequestration risk in the SE TAV group.

Conclusions

Coronary obstruction due to SOV sequestration in redo TAVR may occur in a substantial number of Asian patients. This finding suggests the importance of considering the structural feasibility of future redo TAVR when implanting the first TAV, especially in Asian patients with long life expectancy.