Differences in Valve Morphology and Aortopathy Between Patients with Bicuspid and Tricuspid Aortic Valves: A Computed Tomography Study

Background: Transcatheter aortic valve implantation (TAVI) has been shown safe and feasible in patients with bicuspid aortic valve (BAV) morphology. Evaluation of differences in valve morphology and aortic root dimensions in patients with BAV in comparison to patients with tricuspid aortic valve (TAV) is important for the spread of TAVI in patients with BAV.

Objectives: The present study evaluated the prevalence of BAV subtypes and the differences in valve morphology and aortic root dimensions between BAV and TAV in patients undergoing computed tomography (CT) before TAVI.

Methods: In three medical centers in Israel, 78 patients (70 ± 13.5 years) with BAV and 78 patients (81 ± 8.22 years) with TAV underwent 256-slice CT. BAV morphology was defined according to the number of commissures and raphe: type 0 = no raphe and two commissures, type 1 = one raphe and two commissures, type 2 = two raphes and one commissure. Functional BAV was defined as 3 cusps with focal fusion of 1, 2, or 3 commissures.

Results: Type 0 account for 14%, type IA for 51%, Type IC for 16%, functional BAV for 19%. Type IB and II were not found in the studied population. As compared with TAV patients with BAV have larger aortic annulus area (mean difference 75.8 ± 156 mm/m²; P < 0.001), SOV area (mean difference 205 ± 311 mm/m²; P = < 0.001), STJ area (mean difference 211.79 ± 320.35 mm/m²; < 0.001) and AA Area (mean difference 317 ± 407 mm; P < 0.001); however, the ellipticity index of aortic annulus, sinus of Valsalva, sinotubular junction, and ascending aorta were similar.

Conclusion: In Israel patients with BAV showed more frequently type 1A BAV. BAV patients have larger aortic root dimensions than patients with TAV without difference in regard to the ellipticity index.