Background: Patients with bicuspid aortic stenosis who receive transcatheter aortic valve replacement (TAVR) may require subsequent valve interventions in their lifetime; however, the feasibility of redo-TAVR in this population is uncertain. We aimed to assess redo-TAVR feasibility in bicuspid patients and develop a predictive virtual valve planning algorithm.
Methods: We studied computed tomography scans of bicuspid patients who received a balloon-expandable transcatheter heart valve (THV) in the LRT trial (Low Risk TAVR). Redo-TAVR feasibility, determined by valve-to-coronary and valve-to-aorta measurements on 30-day computed tomography, was assessed according to raphe location and calcification. A virtual valve planning algorithm was developed using baseline and 30-day computed tomography scans.
Results: Among 42 patients (left/right cusp fusion: n=34; right/noncusp fusion: n=4; 2-sinus: n=4), redo-TAVR was feasible in 64%, while 36% would likely require leaflet modification to prevent coronary obstruction. Patients with left/right fusion and calcified raphe had higher redo-TAVR feasibility (88% versus 35%, P<0.001) due to favorable shifting of the THV away from the coronary ostia. A bicuspid virtual planning algorithm accounting for 83.4% THV underexpansion, resulting in an 11.9% taller frame and translation of the THV away from the calcified raphe (mean valve shift 6.6 mm) achieved 86.7% sensitivity and 88.9% specificity for predicting redo-TAVR feasibility.
Conclusions: Calcified raphe in left/right cusp fusion shifts the THV away from the coronary ostia, reducing coronary obstruction risk during redo-TAVR. Underexpansion causing increased THV frame height and valve shifting is common in bicuspid patients; a virtual planning algorithm accounting for these aspects can accurately assess redo-TAVR risk.
Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02628899.
Keywords: aorta; aortic valve; humans; tomography; transcatheter aortic valve replacement.