Does the pattern of bicuspid aortic valve leaflet fusion determine the success of the Ross procedure?

Background: In addition to being associated with aortopathy, a bicuspid aortic valve (BAV) has been posed to be a risk factor for the dilation of the pulmonary autograft in the aortic position. The aim of this study is to assess the association between the subtype of native aortic valve leaflet fusion (right and noncoronary leaflets [R/N] vs right and left leaflets [R/L]) and autograft dilation and valve dysfunction after the Ross procedure.

Methods: We performed a retrospective review of 43 patients with BAV who underwent a Ross procedure in our center from 1993 to 2013. Serial transthoracic echocardiography was used to measure changes in autograft and ascending aortic diameter over time. The aortic diameter was measured at four levels, and Z values were computed. Aortic dilation was defined as a Z value greater than 3.

Results: The mean age at the time of the Ross procedure was 13.5 ± 9.2 years. R/L was the most prevalent native aortic valve subtype (R/L, n = 26, 61% vs R/N, n = 17, 39%). PreRoss procedure, aortic dilation was more frequent in patients with R/N fusion (P = .02), whereas the initial aortic valve gradient and grade of aortic insufficiency (AI) did not differ between the subgroups. At follow-up, (mean = 9.6 ± 4.3 years) dilation of the autograft and ascending aorta was seen more often in patients with R/N leaflet fusion (P = .03). Conversely, the prevalence of more than moderate AI was significantly higher in patients with R/L leaflet fusion (P = .03). There was no significant difference between groups among numbers of late reintervention on the aortic valve or root (P = .75); however the type of intervention varied by morphologic subtype. Patients with R/L fusion underwent more aortic valve replacements (AVRs) while patients with R/N fusion underwent more valve-sparing aortic root replacements.

Conclusions: After Ross procedure, both groups of patients were likely to have a combination of dilation of the aortic root and the tubular portion of the ascending aorta at follow-up. Patients with R/L fusion were more likely to have a prevalence of root dilation, while patients with R/N fusion were more likely to have tubular ascending aorta dilation. The R/L phenotype is associated with a slightly more rapid dilation at follow-up and is more likely to have postoperative autograft insufficiency. This information may serve to guide patient and procedure selection for AVR.