Force results
Segmental force results for the aortic annulus and STJ from MS–MD are presented in Fig. 4 and summarized in Table 2. The total force acting in the STJ from MS–MD was significantly reduced in the double-ring group compared with the single-ring group from 1.7 ± 0.6 to 0.04 ± 1.1 N (P = 0.001). There was no significant difference in the total force at the aortic annulus (single ring: 6.7 ± 3.3 N; double ring: 6.6 ± 2.2 N, P = 0.94), nor any difference in the segmental forces in the aortic annulus. In the STJ, there was a reduced force in the RN and LR segments, but not in the LN segment after double ring compared with single ring. There was a significantly higher force in the LR segment compared with the 2 other segments in the aortic annulus within each group. In the STJ, there was no significant difference in force between segments within each group.
Figure 4:  Segmental force for each of the 3 segments (LN, RN, LR) for single and double ring (mid-systole–mid-diastole). (A) Level of the annulus. (B) Level of the STJ (mean ± standard deviation). LN: left/non-coronary segment; LR: left/right-coronary segment; RN: right/non-coronary segment; STJ: Sinotubular junction.
Table 2:  Segmental force at the level of the annulus and STJ from MD to MS for both groups
Force (N)  Single ring  Double ring   P-value between groups
Annulus LN segment  0.7 ± 1.4  0.6 ± 1.0  NS
Annulus RN segment  1.3 ± 1.0  1.3 ± 1.0  NS
Annulus LR segment  4.3 ± 1.5  4.2 ± 1.1  NS
STJ LN segment  0.2 ± 0.3  0.1 ± 0.3  NS
STJ RN segment  0.7 ± 0.6  0.0 ± 0.3  0.001
STJ LR segment  0.8 ± 0.7  0.0 ± 0.9  0.041
All data are presented as mean ± standard deviation.
LN: left/non-coronary segment; LR: left/right-coronary segment; MD: mid-diastole; MS: mid-systole; NS: non-significant; RN: right/non-coronary segment; STJ: Sinotubular junction.