Adolescents with bicuspid aortic valve: Which criteria should we use for aortic dilatation?

Background: Criteria to define aortic dilatation in bicuspid aortic valve (BAV) patients are different for children and adults. The objective of this study was to find the best reference tool to define dilation of the aortic root (AR) and the ascending aorta (AA) in BAV adolescents with an adult body surface area (BSA).

Methods: Patients recruited were ≥10-years-old with a BSA ≥1.5 m2. Three measurements of the AR and AA were compared: z-score, the BSA-indexed value (BSA-IV) and the absolute value (AV), with thresholds in +2/+3, 21 mm/m2 and 40 mm, respectively.

Results: 231 subjects were collected from the Pediatric REVAB database, with a median age and BSA of 14-year-old and 1.67 m2. Significant differences were reported in the AA: 109 (47%) patients had a z-score ≥2 and 67 (29%) a Z ≥ 3, but only 9 (3%) a BSA-IV ≥21 mm/m2 (p < 0.01 and p < 0.01) and 2 (0.9%) an AV ≥40 mm (p = 0.22 and p = 0.08).

Conclusion: Our results indicate that in the AA there are a significant number of patients in which it would be recommendable changing to BSA-IV when children are older than 10-year-old and BSA ≥1.5 m2. Regarding the AR, criteria for dilatation seems not to be influenced by the reference chosen.