Optimal pre-TAVR annulus sizing in patients with bicuspid aortic valve: area-derived perimeter by CT is the best-correlated measure with intraoperative sizing.

OBJECTIVE: To clarify the optimal measurements for patients with bicuspid aortic valve (BAV) preferred for transcatheter aortic valve replacement (TAVR), our study compared intraoperative sizing with five different approaches by transthoracic echocardiography (TTE), three-dimensional transesophageal echocardiography (3DTEE) and computed tomography (CT). METHODS: We enrolled 104 BAV patients prescreened for TAVR but who underwent surgery with direct intraoperative annulus sizing. All five approaches [2DTTE, 3DTEE, area-derived perimeter (CTarea), perimeter-derived diameter (CTperi) and mean diameter (CTmean)] were compared with intraoperative sizing, respectively. Agreements on theoretical valve selections by five methods with those by intraoperative sizing were analyzed. RESULTS: CTarea showed the highest correlation (r = 0.932) and the best agreement with intraoperative sizing. Agreement for theoretical surgical and TAVR prosthesis selection was found in 84.6% and 74.0% BAVs by CTarea (κ = 0.791, κ = 0.585). CTperi-based prosthesis selection led to overestimation of 26.9% for surgical valves (κ = 0.589) and 36.5% for TAVR valves (κ = 0.425). Good correlations were observed between CT measurements and intraoperative sizing regardless of the predominant site of aortic valve calcification (r = 0.860-0.953). CONCLUSION: The CTarea, which demonstrated the optimal approach to annulus sizing and prosthesis choice of BAVs with high eccentricity, should be included into the BAV-specific annulus sizing recommendation. The insufficiency of CTperi lay in overestimation of surgical or TAVR valve selections. Good agreement of 3DTEE sizing proved its superiority in annulus sizing for BAVs unsuitable for CT, but it should be used with caution for patients with a calcified annulus, where partial acoustic shadowing could lead to image inaccuracy. KEY POINTS: • The area-derived perimeter by CT is the optimal approach to annulus sizing of BAVs. • The perimeter-derived approach is prone to overestimation of BAVs. • 3DTEE showed its superiority in annulus sizing for BAVs unsuitable for CT, but it should be used with caution in patients with a calcified annulus.

Characteristics of aorto-iliofemoral arterial tree according to aortic valve morphology in chinese patients considered for TAVR.

To characterize the anatomy of aorto-iliofemoral arterial tree according to aortic valve phenotype by CT in patients referred for transcatheter aortic valve replacement (TAVR). We retrospectively enrolled 215 patients screened for TAVR who underwent CT. Dimensions, calcification, vascular tortuosity index score and other putative risk features of 13 different regions were evaluated for bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) morphology. The study consisted of 44% BAVs with younger age than TAVs. The dimensions of the annulus, sinus of Valsalva, ascending aorta and aortic arch were consistently larger in BAVs. The prevalence of calcification of aortic arch was significantly higher in TAVs even after adjustment for atherosclerotic risk factors. BAVs was associated with two-fold higher odds of having over I degree AA calcification (odds ratio 2.02; 95% CI 1.60-5.31; p < 0.001). The prevalence of severe iliac tortuosity was higher among BAVs (11.7 vs. 2.5%, p = 0.015). BAVs had a trend to more atheroma than TAVs in the abdominal aortic artery and iliofemoral artery. BAV anatomy is common in Chinese AS patients screened for TAVR. Aorto-iliofemoral pathology varies according to aortic valve phenotype, which may contribute to technical challenges in BAV vs. TAV anatomy and support the need for the integrated risk assessment for each valve phenotype.