The aortic interleaflet triangles annuloplasty : a multidisciplinary appraisal

Objective: Aortic interleaflets triangles annuloplasty (AITA) reduces interleaflet triangles’ circumferential extent through properly placed sutures. To achieve aortic root functional unit (ARFU) stabilization, we aimed at quantifying the effect of suture extent (SE) on aortic valve function and at finding general optimization criteria. Methods: A previously published ARFU finite element model was modified to simulate ARFU dilation and AITA, systematically varying the SE and quantifying the corresponding regurgitant orifice (RO), leaflets co-aptation area (CA) and annular diameter (Da). Computational outcomes were tested by comparison with postoperative virtual basal ring echo data of 105 successfully corrected ARFUs. Results: According to our finite element simulations of AITA, RA and CA depended linearly on SE, through a relationship that predicted optimal surgical results when SE was equal to 48% of the interleaflet triangle height (ITH). Follow-up data showed that, after AITA, ARFU diameter decreased from 23.4 ± 3.93 to 20.1 ± 1.8 mm, (p < 0.05) at the annulus, from 41.53 ± 6.347 to 38.2 ± 4.0 mm, (p < 0.01) at the sinuses, and from 41.3 ± 6.47 to 35.25 ± 5.95 mm (p = ns) at the sinotubular junction (STJ). The mean ITH was 11.18 ± 1.74 mm and the mean SE predicted by our model was 5.34 ± 0.6 mm, that is, 47.76% of the ITH, comparable to 48% of the computational model. Leaflet co-aptation length (CL) increased from 2.73 ± 1.25 to 7.56 ± 2.36 mm (p < 0.001), while the CA evaluated via finite element modeling changed from 8% to 48%. Conclusions: So far, the AITA seems to be a valuable technique to increase leaflet CL in aortic valve repair and in silico models seem to be able to predict the principles of the phenomena but not the individual complexity.