Abstract 14443: Aortic Root Rotational Position Associates With Aortic Valve Incompetence and Aortic Dilation After Arterial Switch Operation for Transposition of the Great Arteries

Introduction: Variation in aortic root (AoR) rotational position affects flow dynamics in normal patients. Complications of arterial switch operation (ASO) for transposition of the great arteries (TGA) include aortic dilation and neo-aortic regurgitation (AR). We sought to assess the association of neo-AoR rotational position with neo-AoR and ascending aorta (AA) dilation and neo-AR in TGA after ASO. Methods: Patients after ASO for TGA who underwent cardiac magnetic resonance (CMR) from 2005-2020 were retrospectively reviewed. Neo-AoR rotational angle, indexed (to height) neo-AoR and AA dimensions, indexed left ventricular end diastolic volume (LVEDVi), and neo-aortic regurgitant fraction (RF) were obtained from CMR. Multivariable regression analysis for neo-AoR and AA dilation, RF, and LVEDVi were performed. Results: A total of 36 patients (78% male) were included. Median age at ASO was 5 days (3, 7) and at CMR was 17.1 years (12.3, 21.9). Rotational angle was 25% counterclockwise (<-9°), 25% central (-9 to +14°), and 50% clockwise (>+15°). There was no material association of neo-AoR and AA size with sex, age, and coronary artery anatomy. A quadratic term for neo-AoR rotational angle - increasing extremes of counterclockwise and clockwise angles - was significantly associated with neo-AoR dilation (p=0.03), AA dilation (p<0.02), and LVEDVi (p<0.01) (Figure 1) and remained significant in multivariable model of neo-AoR dilation (p<0.02), AA dilation (p<0.01), and LVEDVi (p<0.02). Rotational angle was negatively associated with neo-aortic RF (p<0.05) and remained significant in multivariable model (p<0.02). Conclusions: In conclusion, both clockwise and counterclockwise neo-AoR rotational position in TGA after ASO are associated with neo-AoR and AA dilation and LVEDVi. Counterclockwise rotational angle was associated with RF. Neo-AoR rotational position likely affects valve function and hemodynamics, leading to risk of neo-AR and aortic dilation.

Understanding the Rotational Positioning of the Bones in the Medial Column of the Foot: A Weightbearing CT Analysis

Category: Bunion; Midfoot/Forefoot Introduction/Purpose: Rotational deformities of the first ray have been described as essential components of hallux valgus (HV) deformity, influencing its severity and progression. The exact deformity location along the medial column, as well as the typical rotational pattern of each bone, is yet to be fully understood. The objective of this study was to evaluate the rotational position of the navicular, medial cuneiform, first metatarsal and proximal phalanx using three-dimensional weightbearing CT (WBCT) images of a diversity of patients with foot pathologies. Our goal was to describe the rotational profile of medial column bones, serving as a reference for future studies. Methods: A retrospective review of patients that underwent WBCT assessment of multiple foot and ankle pathologies was conducted in a single Institution. A blinded and independent Fellowship-Trained Foot and Ankle Orthopedic Surgeon performed measurements in Multiplanar Reconstruction (MPR) WBCT images assessing the rotational profile of each bone of the medial column (navicular, medial cuneiform, first metatarsal and proximal phalanx of the great toe), as demonstrated in the attached figure. The first metatarsal, representing a long bone, was evaluated on its proximal and distal ends. A total of 110 patients were included. As standard, we considered pronation as positive values and supination as negative values. Comparisons were performed using independent t-tests or Wilcoxon tests. P-values of <0.05 were considered significant. Results: The mean values and 95% Confidence Interval for the rotational profile of the medial column bones were found to be respectively: Navicular, pronated 43.2o (41.1 to 45.2); Medial Cuneiform, supinated -2.5o (-4.3 to -0.7); Proximal First Metatarsal, supinated -28.1o (-32 to -24.1); Distal Metatarsal, pronated 18.5o (16.3 to 20.7); First Toe Proximal Phalanx, pronated of 21.6o (18.7 to 24.5). Significant differences were found in the rotational position of each bone/segment (p<0.0001), with the exception of the distal metatarsal/proximal phalanx (p=0.11), that demonstrated similar amounts of pronation. When considering each segment/joint in isolation, the highest rotational deformity was found to exist within the first metatarsal (pronated 46.6o), naviculo-cuneiform joint (supinated 45.7o), first tarsometatarsal joint (supinated 25.5o) and first metatarsophalangeal joint (pronated 3.1 o). Conclusion: Our study described the rotational profile of the medial column bones using WBCT images, in a population of patients with diverse foot and ankle pathologies. We found significant differences in the rotational position of most of the bones along the medial column. The greatest amount of rotation was found to happen within the first metatarsal, which undergoes an average of 46o of pronation from proximal to distal, probably compensating a considerable amount of supination of the naviculo- cuneiform and first tarsometatarsal joints. Further studies comparing hallux valgus patients and controls are needed.

Decomposition-Based Tracking Control with Particles

In this paper, a new control scheme, called\emph{additive-state-decomposition-based tracking control}, is proposed tosolve the tracking (rejection) problem for rotational position of the TORA (anonlinear nonminimum phase system). By the additive state decomposition, thetracking (rejection) task for the considered nonlinear system is decomposedinto two independent subtasks: a tracking (rejection) subtask for a lineartime invariant (LTI) system, leaving a stabilization subtask for a derivednonlinear system. By the decomposition, the proposed tracking control schemeavoids solving regulation equations and can tackle the tracking (rejection)problem in the presence of any external signal (except for the frequencies at$\pm1$) generated by a marginally stable autonomous LTI system. To demonstratethe effectiveness, numerical simulation is given.

Performance and Nutritional Properties of Einkorn, Emmer and Rivet Wheat in Response to Different Rotational Position and Soil Tillage

Einkorn, emmer, and rivet are three species of wheat that have largely been neglected in modern agriculture. There is a revived interest in these species as potentially successful alternatives to mainstream wheat in organic and low-input cropping systems and as sources of highly nutritious food. However, the availability of literature studies concerning rotational positions and soil tillage management is still scarce. The aim of this study was to explore the field (cover, disease resistance, yield) and quality performance (protein, fats, fiber, polyphenols, flavonoids, and antioxidant activity) of these species when organically grown in the United Kingdom. As part of the H2020 DIVERSIFOOD project, different cultivars of each species, including landraces, populations, old varieties, and where available, commercial varieties, were included in the experiment. Rotational position and tillage systems significantly affected the main agronomic performance of the minor cereals investigated, suggesting that low fertility and shallow-non-inversion tillage might be suitable options to manage tall species. Emmer showed the highest incidence of foliar diseases, whereas einkorn and rivet wheat appeared quasi-immune to the main fungal diseases (stripe rust, septoria). In addition, nutritional and nutraceutical investigation showed that the rotational position and soil management also affect metabolic pathways differently by species and within species, by genotype. Our results suggest a good potential to introduce these species in sustainable cropping systems. Furthermore, the interesting species and cultivar-by-management interactions observed can pave the way for future, better focused, research on these underutilized and underexplored species.