Comparison of pulmonary and aortic root and cusp dimensions in normal adults using computed tomography: potential implications for Ross procedure planning
Abstract OBJECTIVES The Ross procedure is currently receiving renewed interest. Its function and durability depend on preservation of pulmonary valve anatomy; limited data exist on normal pulmonary valve geometry. The objective was to compare aortic and pulmonary root and cusp dimensions in adults with normal tricuspid aortic and pulmonary valves. METHODS We reviewed 507 coronary computed tomography studies, selecting those with adequate visibility of both pulmonary and aortic roots for further analysis. Diastolic aortic and pulmonary root and cusp dimensions were measured. Root dimensions at different phases of the cardiac cycle were measured in 3 patients. RESULTS We analysed studies of 50 patients with the mean age of 54 years [standard deviation (SD): 16]. In end-diastole, pulmonary root had a smaller sinutubular to basal ring ratio than the aortic root [0.82 (SD: 0.09) vs 1.14 (SD: 0.12), P < 0.001]. Aortic and pulmonary cusps had similar dimensions; however, pulmonary cusp effective height was lower [5.9 mm (SD: 1.6) vs 8.4 mm (SD: 1.2), P < 0.001]. Pulmonary basal ring perimeter was largest at end-diastole and smallest at end-systole, with the relative difference of 23.5% (SD: 2.7). CONCLUSIONS The pulmonary root has a similar cusp size compared to the aortic root, but a different shape, resulting in a lower pulmonary cusp effective height. The perimeter of the pulmonary basal ring changes during the cardiac cycle. These findings suggest that stabilizing the autograft to normal aortic, rather than pulmonary, root dimensions should result in normal autograft cusp configuration. Computed tomography angiography could become a tool for personalized planning of the Ross procedure.
Segmental analysis of aortic basal ring dimensions in normal and dilated tricuspid aortic roots
Abstract OBJECTIVES In patients with aortic root aneurysm, the aortic basal ring is frequently dilated. It has been speculated that the muscular part of the basal ring dilates most. The purpose of this study was to analyse the segmental dilatation of the basal ring, comparing normal and dilated roots in patients with tricuspid aortic valves. METHODS Retrospective analysis of computed tomography studies in patients with normal and dilated aortic roots was performed. Lengths of segments of the basal ring corresponding to each of the 3 sinuses, and to the muscular and fibrous parts were measured. Fractions of these segments relative to the total basal ring perimeter were calculated. RESULTS We analysed 152 normal and 126 dilated aortic roots and 86 propensity-matched pairs. Basal ring dilatation was present in all segments of dilated aortic roots with subtle differences between the segments corresponding to the 3 sinuses. The muscular part of the basal ring dilated proportionately to its fibrous part, with no difference in fractions of measured muscular part in normal and dilated roots [42.2% (interquartile range 4.3%) vs 42.1% (interquartile range 6.3%)]. CONCLUSIONS Basal ring dilatation was present in all segments corresponding to the 3 sinuses in dilated aortic roots. Both muscular and fibrous parts dilated equally, supporting the need to stabilize the entire basal ring when performing aortic valve repair surgery.