Thursday, April 25, 2024: 5:38 PM - 7:00 PM
Sheraton Times Square
Room: Central Park
Objective: Valve-preserving root replacement aims at normalizing valve form through restoration of root dimensions. In patients with aortic root aneurysm, the cusps may change in size and shape due to stress imposed by root dilatation. The purpose of this study was to quantify the differences in cusp size and shape in patients with normal and dilated tricuspid aortic roots and in dilated roots with or without aortic regurgitation.
Methods: Retrospective analysis of computed tomography studies in patients with normal and dilated tricuspid aortic roots was performed. Normal root size was defined as sinuses of Valsalva diameter less than 40 mm, dilated root as diameter equal or larger than 45 mm. Aortic root and aortic valve cusp measurements were analyzed to assess the size. Root measurements normalized to basal ring diameter and cusp measurements normalized to geometric height were analyzed to assess the shape of the root and the cusps. Additionally, comparison of dilated roots with or without aortic regurgitation was made.
Results: We analyzed 146 normal and 104 dilated aortic roots and 73 propensity-matched pairs. Dilated roots were larger in all measured dimensions and had a different shape, with increased ratio between commissural and basal ring diameter (1.58 (SD 0.23) vs. 1.11 (SD 0.10), p<0.001) and higher normalized root height (0.92 (SD 0.11) vs. 0.79 (SD 0.07), p<0.001). Cusps in dilated roots were bigger in all measured dimensions (cusp insertion, geometric height, estimated free margin length). The shape of the cusps was elongated with increased normalized cusp insertion length (3.64 (SD 0.39) vs. 3.26 (SD 0.20), p<0.001) and normalized free margin length (2.53 (SD 0.30) vs. 2.16 (SD 0.19), p<0.001). The effective cusp height was higher in dilated roots (13.6 mm (IQR 2.9 mm) vs. 8.7 mm (IQR 1.6 mm), p<0.001). Multivariable linear regression model with geometric height as the dependent variable was constructed using all (unmatched) patient data (adjusted R2 = 0.847). Commissural diameter was the strongest positive predictor of cusp geometric height, followed by basal ring diameter, body height and male gender. Age had a small negative correlation with geometric height. In the dilated root group, we selected patients without any cusp prolapse (n = 83) and compared patients with no or mild (grade 0-1) versus moderate to severe (grade 2-4) aortic regurgitation. The commissural diameter and effective cusp height were significantly larger in patients with aortic regurgitation, however the cusp dimensions were similar in both groups.
Conclusions: In the dilated roots most of the dilatation occurred at the level of the sinuses of Valsalva and the commissures, and it was associated with mild root elongation. The cusps in dilated roots were elongated transversely (increasing free margin lengths and cusp insertion length) and to a lesser degree radially (increasing the cusp geometric height). The most important predictor of cusp geometric height was commissural diameter, which was significantly larger in dilated roots. In patients with dilated roots and no cusp prolapse the functional aortic regurgitation was caused by extensive commissural dilatation and not by inadequate cusp growth. Thus, marked changes of cusp dimensions exist in correlation with root size which will have to be accommodated in valve-preserving surgery to produce normal aortic valve form.
Authors
Matija Jelenc (1), Blaž Jelenc (2), Sara Habjan (1), Thomas Foley (3), Peter Fries (4), Hector Michelena (3), Hans-Joachim Schäfers (4)
Institutions
(1) University Medical Center Ljubljana, Slovenia, (2) University of Ljubljana, Slovenia, (3) Mayo Clinic, Rochester, Minnesota, United States, (4) Saarland University Medical Centre, Homburg/Saar, Germany
PODS will be on display in the exhibit hall for the duration of the meeting during exhibit hall hours. PODS will also be available for viewing on the meeting website. There is no formal presentation associated with your POD, but we encourage you to visit the PODS area during breaks to connect with those viewing.