Regional long-term analysis of dietary isotopes in Neolithic southeastern Italy: new patterns and research directions.

Isotopic analyses of prehistoric diet have only recently reached the threshold of going beyond site-focused reports to provide regional syntheses showing larger trends. In this work we present the first regional analysis for Neolithic southeastern Italy as a whole, including both substantial original data and a review of the available published data. The results show that dietary isotopes can shed new light on a number of traditional and important questions about Neolithic foodways. First, we observe regional variations in the distribution of stable isotope values across the area, suggesting variability in the Neolithic diet. Secondly, we show that, although the plant food calorific intake was primary for these communities, animal products were also important, representing on average 40% of the total calories. Third, we note that marine fish was only minorly consumed, but that this could be an underestimation, and we observe some variability in the regions considered, suggesting differences in local human-environment interactions. People in different regions of southeastern Italy may have consumed different versions of a common Neolithic diet. Regional synthesis also allows us to take stock of gaps and new directions in the field, suggesting an agenda for Neolithic isotopic research for the 2020s.

Baseline concussion assessment performance by sex in military service academy rugby players: findings from the CARE Consortium.

BACKGROUND: Normative student-athlete concussion assessment data may not be appropriate for service academy members (SAMs), particularly rugby players, because of the uniqueness of their academic/military training environment. Having accurate baseline data for this population is important because of their high risk for concussion and frequent lack of assigned sports medicine professional. The primary purpose of this study was to characterise baseline performance on a concussion assessment battery, with secondary purpose to determine effect of sex and concussion history on these measures among SAM rugby players. METHODS: 601 rugby-playing SAMs (19.3±1.5 years, 37.9% female) completed baseline concussion assessments: the Sport Concussion Assessment Tool (SCAT) Symptom and Symptom Severity Checklist, Standard Assessment of Concussion (SAC) and a neuropsychological test (either ImPACT (Immediate Post Concussion Assessment and Cognitive Testing) or ANAM (Automated Neuropsychological Assessment Metrics)). Groups were compared using an independent samples t-test or Mann-Whitney U test. A 2 (sex) × 2 (concussion history) ANOVA was conducted to determine the effects of sex and concussion history on outcomes. RESULTS: Women reported greater SCAT total symptoms (3.3 vs 2.8, p<0.001, r=0.143) and symptom severities (5.7 vs 4.3, p<0.001, r=0.139), and performed worse on ImPACT Visual Memory (79.3 vs 82.6, p=0.002, r=0.144) than men. Women performed better than men on SAC (28.0 vs 27.7, p=0.03, r=0.088), ImPACT Reaction Time Composite (0.59 vs 0.61, p=0.04, r=0.092) and ANAM Code Substitution Delayed (64.3 vs 61.5, p=0.04, d=0.433). Individuals with a history of concussion reported lower ImPACT Symptom Severity (2.6 vs 4.2, p=0.02, r=0.110). There was no interaction between concussion history and sex on outcomes. CONCLUSIONS: These findings provide reference data for SAM rugby players on baseline assessments and to help in clinical decision-making when managing sports-related concussion in absence of baseline data.

Residential Water Meters as Edge Computing Nodes: Disaggregating End Uses and Creating Actionable Information at the Edge.

We present a new, open source, computationally capable datalogger for collecting and analyzing high temporal resolution residential water use data. Using this device, execution of water end use disaggregation algorithms or other data analytics can be performed directly on existing, analog residential water meters without disrupting their operation, effectively transforming existing water meters into smart, edge computing devices. Computation of water use summaries and classified water end use events directly on the meter minimizes data transmission requirements, reduces requirements for centralized data storage and processing, and reduces latency between data collection and generation of decision-relevant information. The datalogger couples an Arduino microcontroller board for data acquisition with a Raspberry Pi computer that serves as a computational resource. The computational node was developed and calibrated at the Utah Water Research Laboratory (UWRL) and was deployed for testing on the water meter for a single-family residential home in Providence City, UT, USA. Results from field deployments are presented to demonstrate the data collection accuracy, computational functionality, power requirements, communication capabilities, and applicability of the system. The computational node's hardware design and software are open source, available for potential reuse, and can be adapted to specific research needs.

The head shaft angle is associated with hip displacement in children at GMFCS levels III-V - a population based study.

BACKGROUND: An increased Head Shaft Angle (HSA) has been reported as a risk factor for hip displacement in children with cerebral palsy (CP) but opinions differ in the literature. The purpose of this study was to re-evaluate the relationship between HSA and hip displacement in a different population of children with CP. METHODS: The Cerebral Palsy Integrated Pathway Scotland surveillance programme includes 95% of all children with CP in Scotland. The pelvic radiographs from 640 children in GMFCS levels III-V were chosen. The most displaced hip was analysed and the radiographs used were those taken at the child's first registration in the database to avoid the potential effects of surveillance on subsequent hip centration. A logistic regression model was used with hip displacement (migration percentage [MP] ≥40%) as outcome and HSA, GMFCS, age and sex as covariates. RESULTS: The MP was ≥40% in 118 hips with a mean HSA of 164° (range 121-180°) and < 40% in 522 hips with a mean HSA of 160° (range 111-180°). The logistic regression analysis showed no significant influence of age and sex on MP in this population but a high GMFCS level was strongly associated with hip displacement. An increased HSA was also associated with hip displacement, a 10° difference in HSA for children adjusted for age, sex, and GMFCS gave an odds ratio of 1.26 for hip displacement equal or above 40% (p = 0.009) and hips with HSA above 164.5 degrees had an odds ratio of 1.96 compared with hips with HSA below 164.5 degrees (p = 0.002). CONCLUSION: These findings confirm that HSA is associated with hip displacement in children in GMFCS levels III-V.

Hip displacement in children with cerebral palsy in Scotland: a total population study.

PURPOSE: The purpose of this study is to report the number of children from a total population of children with cerebral palsy (CP) in Scotland who had a displaced or dislocated hip at first registration in a national surveillance programme. METHODS: Migration percentage (MP), laterality, Gross Motor Function Classification System (GMFCS) level, CP subtype, distribution of CP and age were analyzed in 1171 children. Relative risk was calculated with 95% confidence intervals. Hip displacement and dislocation were defined as a MP of 40 to 99 and > 100 respectively. RESULTS: Radiographs were available from the first assessment of 1171 children out of 1933 children registered on the system. In all, 2.5% of children had either one or both hips dislocated (29/1171) and dislocation only occurred in children of GMFCS levels IV and V. A total of 10% of children had a MP 40 to 99 in one or both hips (117/1171). An increasing GMFCS level was strongly associated with an abnormal MP. Hip dislocation was unusual in patients under the age of seven years. A MP of 40 to 99 was not seen in children with isolated dystonia. Displacement was more frequent in children with bilateral involvement and dislocation was only seen in spastic and mixed tone groups. CONCLUSION: This data gives an overview of the number of CP children who have hip displacement/dislocation in Scotland and who will possibly require surgery. LEVEL OF EVIDENCE: I.

Epistatic influence in tomato Ve1-mediated resistance.

Resistance to Verticillium wilt disease is associated with the tomato Ve-locus; however, the individual functional roles of Ve1 and Ve2 in host plants remain controversial. As a first step towards Ve mutational analyses in planta, the Ve1 coding region from a resistant tomato near-isoline (cv. Craigella GCR218) was introduced into a susceptible near-isoline (cv. Craigella GCR26). 35S:Ve1 plants segregated into two distinct classes; roughly half were resistant and half were susceptible. Ve1 transcript levels were up-regulated in both classes compared to wild-type plants, showing stable transgenic expression. Expression analysis of Ve2 revealed that mRNA levels were similar between 35S:Ve1 and wild-type tomatoes, demonstrating that Ve1 transgene introduction does not alter endogenous Ve2 expression. Overall, the results of this study confirm the functional role of Ve1 protein in resistance to the vascular fungal pathogen V. dahliae race 1 (Vd1), but suggest that a yet undefined factor exerts an epistatic influence on the Ve1 gene.

A cohort study of tibialis anterior tendon shortening in combination with calf muscle lengthening in spastic equinus in cerebral palsy.

The aim of this study was to evaluate the outcome of combined tibialis anterior tendon shortening (TATS) and calf muscle-tendon lengthening (CMTL) in spastic equinus. Prospectively collected data was analysed in 26 patients with hemiplegic (n=13) and diplegic (n=13) cerebral palsy (CP) (GMFCS level I or II, 14 males, 12 females, age range 10-35 years; mean 16.8 years). All patients had pre-operative 3D gait analysis and a further analysis at a mean of 17.1 months (±5.6months) after surgery. None was lost to follow-up. Twenty-eight combined TATS and CMTL were undertaken and 19 patients had additional synchronous multilevel surgery. At follow-up 79% of patients had improved foot positioning at initial contact, whilst 68% reported improved fitting or reduced requirement of orthotic support. Statistically significant improvements were seen in the Movement Analysis Profile for ankle dorsi-/plantarflexion (4.15°, p=0.032), maximum ankle dorsiflexion during swing phase (11.68°, p<0.001), and Edinburgh Visual Gait Score (EVGS) (4.85, p=0.014). Diplegic patients had a greater improvement in the EVGS than hemiplegics (6.27 -vs- 2.21, p=0.024). The originators of combined TATS and CMTL showed that it improved foot positioning during gait. The present study has independently confirmed favourable outcomes in a similar patient population and added additional outcome measures, the EVGS, foot positioning at initial contact, and maximum ankle dorsiflexion during swing phase. Study limitations include short term follow-up in a heterogeneous population and that 19 patients had additional surgery. TATS combined with CMTL is a recommended option for spastic equinus in ambulatory patients with CP.

Using a goal attainment scale in the evaluation of outcomes in patients with diplegic cerebral palsy.

A goal attainment scale (GAS) was used to evaluate outcomes of surgical and non-surgical interventions to improve gait in 45 children with diplegic cerebral palsy. Personal goals were recorded during pre-intervention gait analysis in two groups. Twenty children underwent orthopaedic surgery (Group 1) and 25 children received a non-operative intervention (Group 2). Children and/or their carers were contacted post-intervention by telephone to complete a GAS questionnaire, rating the achievement of goals on a 5-point scale. The goals were similar in both groups. The composite GAS was transformed into a standardised measure (T-score) for each patient. Both groups on average achieved their goals (mean T-score for Group 2 was 56.3, versus 47.1 for Group 1). The difference between these two means was significant (p=0.010). Additionally, 16 children had undergone a follow-up gait analysis during the study period, but the relationship between their Gait Profile Score and GAS was not statistically significant. Both surgical and non-surgical interventions enabled children to achieve their goals, although Group 1 reported higher achievements. The GAS reflects patient's/parent's/carer's aspirations and may be as relevant as post-intervention kinematic or kinetic outcomes.

Hemiarch replacement with concomitant antegrade stent grafting of the descending thoracic aorta versus total arch replacement for treatment of acute DeBakey I aortic dissection with arch tear†.

OBJECTIVES: For acute DeBakey I aortic dissection with arch tear, conventional distal reconstruction entails total arch replacement (TAR). Some surgeons at our institution have utilized an alternative reconstructive strategy-primary arch tear repair and transverse hemiarch reconstruction (THR) with concomitant antegrade thoracic endovascular aortic repair (TEVAR). We assessed early and mid-term outcomes comparing these two surgical strategies for arch tear management. METHODS: A retrospective review of a prospectively maintained institutional aortic dissection database was carried out to compare early and mid-term outcomes for patients undergoing intervention for DeBakey I aortic dissection with arch tear. Hemiarch reconstruction with concomitant antegrade TEVAR was compared against conventional TAR. Arch tear at the origin of great vessels or greater curve was primarily repaired with interrupted sutures in TEVAR patients. RESULTS: From 2006 to 2013, 61 of 284 DeBakey I aortic dissection patients undergoing intervention for arch tear were retrospectively reviewed. Thirty-one patients had TAR (TAR group) and 30 patients had hemiarch + TEVAR (TEVAR group). Demographics and clinical presentation were similar. TEVAR group had more patients presenting in cardiogenic shock [3% (n = 1) vs 13% (n = 4), P = 0.2] and tamponade [10% (n = 3) vs 23% (n = 7), P = 0.2]. Intraoperatively, TEVAR group had lower cardiopulmonary bypass (239 ± 34 vs 313 ± 80 min, p0.001) and circulatory arrest (60 ± 15 vs 78 ± 45 min, P = 0.04) times. TAR group had higher in-hospital/30-day mortality [26% (n = 8) vs 13% (n = 4), P = 0.3], but stroke rates were similar [6% (n = 2) vs 7% (n = 2), P = 1]. One-year (80 ± 7.3 vs 71 ± 8.3%), 3-year (73 ± 8.3 vs 67 ± 8.6%) and 5-year (73 ± 8.3 vs 67 ± 8.6%) actuarial survival were improved in TEVAR group, although not significantly (log-rank, P = 0.56). TEVAR promoted increased false lumen thrombosis (43 vs 85%, P = 0.002). CONCLUSION: In treating DeBakey I aortic dissection with arch tear, hemiarch replacement with primary tear repair and concomitant TEVAR is a safe alternative to conventional TAR, with improved distal aortic remodelling.

The relationship between the Edinburgh Visual Gait Score, the Gait Profile Score and GMFCS levels I-III.

OBJECTIVE: To determine the relationship between the Edinburgh Visual Gait Score (EVGS) and the Gait Profile Score (GPS). METHOD: Three dimensional gait data and EVGS scores from 151 diplegic children (Gross Motor Function Classification System (GMFCS) levels I-III) were used for analysis. RESULTS: The EVGS correlated strongly with GPS (r=0.816). There was a significant difference in both gait scores between each level of the GMFCS. CONCLUSIONS: The strong correlation of GPS with EVGS implies that any advantages of using GPS can also be applied to centres without 3-dimensional gait analysis facilities if the EVGS is used.

A meta-analysis assessing the benefits of concomitant pleural tent procedure after upper lobectomy.

A meta-analysis comparing outcomes of upper lobectomies with or without pleural tenting was performed. Five trials comprising 396 patients were selected. There was significantly reduced duration of hospital stay, chest drain use, and air leak in the pleural tenting group compared with the group without the pleural tent. There was also a significant reduction in number of patients with prolonged air leak more than 7 days in pleural tenting group. No other difference was noted in other outcomes such as total drainage, operative time, or hospital costs. In patients at high-risk of air leak, we advocate concomitant use of the pleural tent after upper lobectomies.

A meta-analysis comparing muscle-sparing and posterolateral thoracotomy.

We compared outcomes of posterolateral thoracotomy vs muscle-sparing thoracotomy after open thoracic operations. Twelve trials were included, comprising 571 patients in the muscle-sparing thoracotomy group and 512 patients in the posterolateral thoracotomy group. There was significantly improved shoulder internal rotation (weighted mean difference, -1.28; 95% confidence interval, -2.45 to -0.11; p = 0.03) and pain scores on day 7 (weighted mean difference, -0.76; 95% confidence interval, -1.26 to -0.27; p = 0.002) but higher seroma rates (odds ratio, 8.26; 95% confidence interval, 2.16 to 31.56; p = 0.002) in the muscle-sparing thoracotomy group compared with the posterolateral thoracotomy group. We advocate using muscle-sparing thoracotomy, especially on patients dependant on quicker recovery of shoulder function.

A model of ischemic mitral regurgitation in pigs with three-dimensional echocardiographic assessment.

BACKGROUND AND AIM OF THE STUDY: Ischemic mitral regurgitation (IMR), the incidence of which is increasing, results from annular and subvalvular remodeling after myocardial infarction (MI). Although a sheep model of IMR has been used extensively over the past two decades, the ventricular, coronary and leaflet anatomy in sheep is significantly different from that in humans. In contrast, pigs are more similar to humans with regard to these parameters, and therefore may serve as a better animal to test emerging new technologies designed to treat IMR. METHODS: Twenty-nine pigs (body weight 30-35 kg) underwent left thoracotomy and ligation of the mid main circumflex and distal right posterior descending coronary arteries to create a posterolateral MI. Of these pigs, 18 were used for acute data acquisition, while 11 surviving animals in the chronic group were assessed at eight weeks after MI. Real-time three-dimensional echocardiography was performed at baseline, and at 30 min and eight weeks after MI, to assess geometric changes in the mitral annulus, mitral leaflets and left ventricle. RESULTS: Compared to baseline, the MR grade was increased significantly at eight weeks (0.7 + 0.5 versus 2.0 +/- 1.2), together with a significant decrease in left ventricular ejection fraction (40.3 +/- 6.6% versus 25.8 +/- 7.7%). Significant increases were also noted at eight weeks in the commissural width (30.1 +/- 3.2 mm versus 35.1 +/- 2.9 mm) and septolateral diameter (25.0 +/- 2.0 mm versus 33.8 +/- 5.9 mm), with a resultant increase in mitral annular area (596 +/- 85 versus 931 +/- 181 mm3) and a decrease in the annular height to commissural width ratio (15.7 +/- 2.6% versus 13.7 +/- 1.9%). The mitral valve tenting volume was also increased significantly (1577 +/- 645 versus 2440 +/- 755 mm3). The distance between the papillary muscle tips at baseline and at eight weeks was increased significantly (23.9 +/- 2.5 versus 30.9 +/- 5.2 mm), as was the distance between the posterior papillary muscle tip and the posterior commissure (20.9 +/- 2.7 versus 24.1 +/- 2.8 mm). CONCLUSION: The surgical model described here reliably replicates the changes seen in humans with IMR. Hence, this model can be used for further studies of the pathophysiology of IMR, and of any novel interventions in this challenging clinical area.

Sutureless mitral valve replacement: initial steps toward a percutaneous procedure.

PURPOSE: Transcatheter mitral valve replacement would represent a major advance in heart valve therapy. Such a device requires a specialized anchoring and sealing technology. This study was designed to test the feasibility of a novel mitral valve replacement device (the sutureless mitral valve [SMV]) designed to anchor and seal in the mitral position without need for sutures. DESCRIPTION: The SMV is a self-expanding device consisting of a custom-designed nitinol framework and a pericardial leaflet valve mechanism. EVALUATION: Ten sheep underwent successful surgical SMV device implantation. All animals underwent cardiac catheterization 6 hours postoperatively. Hemodynamic, angiographic, echocardiographic and necroscopic data were recorded. The mean aortic cross-clamp time was 9.5 ± 3.1 minutes. Echocardiography and angiography revealed excellent left ventricular systolic function, no significant perivalvular leak, no mitral valve stenosis, no left ventricular outflow tract obstruction, and no aortic valve insufficiency. Necropsy demonstrated that the SMV devices were anchored securely. CONCLUSIONS: This study demonstrates the feasibility and short-term success of sutureless mitral valve replacement using a novel SMV device.

Hip surveillance and management of the displaced hip in cerebral palsy.

INTRODUCTION: This article provides an overview of the management of a displaced hip in children with cerebral palsy and considers surveillance programmes, principles of surgical reconstruction and options for the salvage of an unreconstructable hip in these children. CONCLUSION: Hip dislocation in CP is potentially preventable if children are included from an early age in a surveillance programme that includes repeat radiographic and clinical examinations, and preventive treatment for hips that are displacing. A surveillance programme should be based on the child's age, GMFCS level and migration percentage (MP), and surgical prevention may be considered in children with a MP exceeding 33 %.

Posterior leaflet augmentation in ischemic mitral regurgitation increases leaflet coaptation and mobility.

BACKGROUND: Restoring leaflet coaptation is the primary objective in repair of ischemic mitral regurgitation (IMR). The common practice of placing an undersized annuloplasty ring partially achieves this goal by correcting annular dilation; however, annular reduction has been demonstrated to exacerbate posterior leaflet tethering. Using a sheep model of IMR, we tested the hypothesis that posterior leaflet augmentation (PLA) combined with standard annuloplasty sizing increases leaflet coaptation more effectively than undersized annuloplasty alone. METHODS: Eight weeks after posterobasal myocardial infarction, 15 sheep with 2+ or greater IMR underwent annuloplasty with either a 24-mm annuloplasty ring (24-mm group, n = 5), 30-mm ring (30-mm group, n = 5), or 30-mm ring with concomitant augmentation of the posterior leaflet (PLA group, n = 5). Using three-dimensional echocardiography, postrepair coaptation zone and posterior leaflet mobility were assessed. RESULTS: Leaflet coaptation length after repair was greater in the PLA group (4.1 ± 0.3 mm) and the 24-mm group (3.8 ± 0.5 mm) as compared with the 30-mm group (2.7 ± 0.6 mm, p < 0.01). Leaflet coaptation area was significantly greater in the PLA group (121.5 ± 6.6 mm(2)) as compared with the 30-mm group (77.5 ± 17.0 mm(2)) or the 24-mm group (92.5 ± 17.9 mm(2), p < 0.01). Posterior leaflet mobility was significantly greater in the PLA group as compared with the 30-mm group or the 24-mm group. CONCLUSIONS: Posterior leaflet augmentation combined with standard-sized annuloplasty enhances leaflet coaptation more effectively than either standard-sized annuloplasty or undersized annuloplasty alone. Increased leaflet coaptation after PLA provides redundancy to IMR repair, and may decrease incidence of both recurrent IMR and mitral stenosis.

An ovine model of pulmonary insufficiency and right ventricular outflow tract dilatation.

BACKGROUND AND AIM OF THE STUDY: The treatment of pulmonary insufficiency (PI) following reconstructive surgery of the right ventricular outflow tract (RVOT) in repair of the tetralogy of Fallot remains a significant challenge. The study aim was to establish an ovine model of dilated RVOT and PI, and to quantify the degree of PI and right ventricular remodeling over an eight-week period, using magnetic resonance imaging (MRI). METHODS: Five sheep underwent baseline MRI scanning and catheterization. The weight-indexed right and left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF) and pulmonary regurgitant fraction (RF) were measured at baseline. The animals then underwent pulmonary valvectomy and transannular patch repair of the RVOT. Repeat MRI and hemodynamic measurements were obtained after an eight-week period. RESULTS: The indexed RVEDV increased from 49 +/- 4.0 ml/m2 at baseline to 80 +/- 10.3 ml/m2 at eight weeks after valvectomy (p = 0.01), while the indexed RVESV increased from 13 +/- 3.4 ml/m2 to 33 +/- 8.8 ml/m2 (p = 0.01). The indexed RVSV increased from 36 +/- 3.7 ml/m2 to 47 +/- 1.7 ml/m2 (p = 0.01). The RVEF at baseline was 74 +/- 6%, and this decreased to 59 +/- 5% at follow up (p = 0.02). The RF at baseline was 0 +/- 0% and was increased to 37 +/- 3% at eight weeks after valvectomy (p < 0.001). The left ventricular (LV) function was also diminished: LVEF at baseline was 67 +/- 2%, versus 49 +/- 10% at follow up (p = 0.01). Both, the RV and LV end-diastolic pressures were significantly elevated at follow up. CONCLUSION: All five animals developed pulmonary regurgitation sufficient to cause significant RV dilatation and diminished RV and LV functions. This model may be used to investigate novel therapeutic approaches in the treatment of this difficult clinical problem.

A novel method for quantifying the in-vivo mechanical effect of material injected into a myocardial infarction.

BACKGROUND: Infarcted regions of myocardium exhibit functional impairment ranging in severity from hypokinesis to dyskinesis. We sought to quantify the effects of injecting a calcium hydroxyapatite-based tissue filler on the passive material response of infarcted left ventricles. METHODS: Three-dimensional finite element models of the left ventricle were developed using three-dimensional echocardiography data from sheep with a treated and untreated anteroapical infarct, to estimate the material properties (stiffness) in the infarct and remote regions. This was accomplished by matching experimentally determined left ventricular volumes, and minimizing radial strain in the treated infarct, which is indicative of akinesia. The nonlinear stress-strain relationship for the diastolic myocardium was anisotropic with respect to the local muscle fiber direction, and an elastance model for active fiber stress was incorporated. RESULTS: It was found that the passive stiffness parameter, C, in the treated infarct region is increased by nearly 345 times the healthy remote value. Additionally, the average myofiber stress in the treated left ventricle was significantly reduced in both the remote and infarct regions. CONCLUSIONS: Overall, injection of tissue filler into the infarct was found to render it akinetic and reduce stress in the left ventricle, which could limit the adverse remodeling that leads to heart failure.

Posterior leaflet augmentation improves leaflet tethering in repair of ischemic mitral regurgitation.

OBJECTIVES: Ischemic mitral regurgitation results from annular dilatation, leaflet tethering and leaflet flattening. Undersized annuloplasty corrects annular dilatation but worsens leaflet tethering and flattening. This exacerbation of abnormal leaflet geometry may contribute to poor repair results for ischemic mitral regurgitation (IMR). Using a sheep model of IMR, we hypothesized that posterior leaflet augmentation and less-extreme annular undersizing would relieve tethering and increase leaflet curvature. METHODS: Eight weeks after posterolateral infarct, 10 sheep with ≥ 2+ IMR underwent either a 24-mm planar ring annuloplasty (n = 5) or a 30-mm planar ring annuloplasty with concomitant posterior leaflet augmentation (n = 5). Real-time three-dimensional echocardiography allowed measurement of indices of leaflet curvature and tethering before and after annuloplasty. RESULTS: Comparing pre- and post-repair values in the P1, P2, and P3 leaflet regions, undersized 24-mm ring annuloplasty made no significant difference to mean septolateral curvature (0.23-0.26, 0.33-0.29, and 0.27-0.37 cm(-1), respectively), whereas leaflet augmentation in combination with a 30-mm ring annuloplasty increased septolateral curvature (P1 0.30-1.02, P2 0.31-1.23, and P3 0.35-0.84 cm(-1), p-values<0.05). The mean tethering angle formed between the annular plane and the posterior leaflet increased in all three posterior regions for the 24-mm ring group (P1 12-23°, P2 26-31°, and P3 16-25°), but decreased in all regions for the group undergoing leaflet augmentation (P1 +5 to -6°, P2 +13 to -13°, P3 +16-15°, all p-values < 0.05). CONCLUSIONS: Undersized annuloplasty exacerbates leaflet tethering. Posterior leaflet augmentation with less severe annular reduction increases leaflet curvature and decreases tethering; this technique more completely addresses the pathogenic mechanism of IMR and may improve repair durability.