Abstract 4242: Variability in the Shape of Balloon-expandable Transcatheter Aortic Valve Prostheses and its Association with Native Valve Morphology and Subsequent Prosthetic Aortic Regurgitation
Background: Percutaneous aortic valve implantation (PAVI) is a promising new treatment for high risk surgical patients with severe aortic stenosis (AS). A recent study suggested that self-expanding transcatheter aortic prostheses may have non-circular orifices but the shape of balloon-expanded prostheses has not been studied.
Methods: Patients with severe, symptomatic AS had real-time 3-D and 2-D transesophageal echo performed during implantation of an Edwards Sapien transcatheter aortic valve (AV). Off-line analysis of 3-D datasets was used determine native AV area by planimetry (AVAPlan) and PAVI orthogonal diameters (labeled D1 and D2). PAVI area was calculated by Doppler. The D1/D2 ratio was determined in order to characterize the PAVI as circular (ratio > 0.9) or noncircular (ratio < 0.9). The morphology of native AV opening was characterized as being symmetric (<33% of commissural fusion in a “star” pattern) or asymmetric (>33% of asymmetric commissural fusion) based on a previously described classification. Aortic regurgitation (AR) was classified as trace/mild or greater than mild.
Results: A total of 8 patients (5 males, age of 82 ± 7 yrs) underwent successful PAVI with reduction in pressure gradient from 71 ± 28 to 21 ± 12 mmHg (p<0.001). When grouped by valve morphology (Table 1⇓) there is a significant difference between AVAPlan, D1/D2 ratio and PAVI area. All patients with asymmetric native valve opening had more than trace/mild AR whereas no patient with a symmetric valve opening had significant AR (p < 0.02).
Conclusion: In this population of severe, symptomatic AS patients, asymmetrically calcified aortic valves have smaller anatomic AV areas and noncircular, often irregularly-shaped PAVI. The resulting noncircular prosthetic valves have a smaller areas and more aortic regurgitation than valves that are circular suggesting that the morphology of the native calcified AV may determine whether balloon-expanded prostheses can be maximally deployed.