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 two medical centers in Israel, 49 patients (67 ± 16 years) with BAV and 49 patients (80 ± 7 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 (1A: raphe between left and right cusp, 1B: raphe between left and non-coronary cusp, 1C: raphe between non-coronary and right cusp), type 2 = two raphes and one commissure. Functional BAV was defined as 3 cusps with focal fusion of 1, 2, or 3 commissures. Aortic root dimensions were measured at the level of the aortic annulus, sinus of Valsalva (SOV), sinotubular junction (STJ), and ascending aorta (AA). The distance of coronary artery ostia to the aortic annulus plane was also determined.
RESULTS: Type 0 account for 12% (6/49), type IA for 53% (26/49), Type IC for 14% (7/49), functional BAV for 20% (10/49). 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 97.8 ± 107mm/m2; P = 0.002), SOV mean diameter (mean difference 8.9 ± 6.2mm; P = 0.011), STJ mean diameter (mean difference 4.7 ± 7.5mm; P = 0.006) and AA mean diameter (mean difference 6.3 ± 7.8 mm; P < 0.001); however, the ellipticity index of aortic annulus, SOV, STJ, and AA were similar. No differences were found between BAV and TAV in regard to the distances of coronary artery ostia to the aortic annulus plane.
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. These findings have important implications for prosthesis type and size selection for TAVI.
