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Background: Direct transcatheter aortic valve replacement (TAVR) is regarded as having potential advantages over TAVR with balloon aortic valve predilatation (BAVP) in reducing procedural complications, but there are few data to support this approach., Methods and Results: Patients included in the Brazilian TAVR registry with CoreValve and Sapien-XT prosthesis were compared according to the implantation technique, with or without BAVP. Clinical and echocardiographic data were analyzed in overall population and after propensity score matching. A total of 761 consecutive patients (BAVP=372; direct-TAVR=389) were included. Direct-TAVR was possible in 99% of patients, whereas device success was similar between groups (BAVP=81.2% versus direct-TAVR=78.1%; P=0.3). No differences in clinical outcomes at 30 days and 1 year were observed, including all-cause mortality (7.6% versus 10%; P=0.25 and 18.1% versus 24.5%; P=0.07, respectively) and stroke (2.8% versus 3.8%; P=0.85 and 5.5% versus 6.8%; P=0.56, respectively). Nonetheless, TAVR with BAVP was associated with a higher rate of new onset persistent left bundle branch block with the CoreValve (47.7% versus 35.1%; P=0.01 at 1 year). Mean gradient and incidence of moderate/severe aortic regurgitation were similar in both groups at 1 year (11% versus 13.3%; P=0.57 and 9.8±5.5 versus 8.7±4.3; P=0.09, respectively). After propensity score matching analysis, all-cause mortality and stroke remained similar. By multivariable analysis, BAVP and the use of CoreValve were independent predictors of new onset persistent left bundle branch block., Conclusions: The 2 TAVR strategies, with or without BAVP, provided similar clinical and echocardiographic outcomes over a midterm follow-up although BAVP was associated with a higher rate of new onset persistent left bundle branch block, particularly in patients receiving a CoreValve., (© 2016 American Heart Association, Inc.)

Background: It has been speculated that the immediate decrease in body fat following liposuction may affect body composition by feedback mechanisms of body fat regain. Physical activity has both short- and long-term impacts on health. Although the lay public often associates higher levels of physical activity with body fat distribution changes, studies on the association between physical activity and body fat distribution present inconsistent results. The aim of this study was to investigate the cross-sectional and prospective associations between physical activity and body mass index following liposuction., Methods: This is a prospective, bidirectional, cross-sectional study, including 526 liposuction patients, who were followed up at a mean of 11.7 and 24.3 months after surgery., Results: The sum of skinfolds at 11.7 months was highly correlated with skinfolds at 24.3 months (rho = 0.74, p < 0.001). More than 85 percent of participants remained in the same quintile or changed by not more than one quintile during the 13.6-month period. Tracking of physical activity was considerably lower but still significant; the correlation was 0.24 (p < 0.001), and 61.4 percent of the patients moved one or less quintiles. In fully adjusted models, no significant cross-sectional or longitudinal associations were found between physical activity and body mass index., Conclusions: The authors provide evidence of tracking of physical activity and particularly body mass index following liposuction. The authors' results do not support the hypothesis that physical activity and fatness are strongly related following liposuction.

Objective: Hostility is associated with cardiovascular mortality and morbidity, and one of the mechanisms may involve heightened reactivity to mental stress. However, little research has been conducted in populations at high risk for cardiovascular disease. The aim of the present study was to assess the relationship between hostility and acute stress responsivity in individuals with Type 2 diabetes., Methods: A total of 140 individuals (median age [standard deviation] 63.71 [7.00] years) with Type 2 diabetes took part in laboratory-based experimental stress testing. Systolic blood pressure, diastolic blood pressure, heart rate, plasma interleukin-6 (IL-6), and salivary cortisol were assessed at baseline, during two stress tasks, and 45 and 75 minutes later. Cynical hostility was assessed using the Cook Medley Cynical Hostility Scale., Results: Participants with greater hostility scores had heightened increases in IL-6 induced by the acute stress tasks (B = 0.082, p = .002), independent of age, sex, body mass index, smoking, household income, time of testing, medication, and baseline IL-6. Hostility was inversely associated with cortisol output poststress (B = -0.017, p = .002), independent of covariates. No associations between hostility and blood pressure or heart rate responses were observed., Conclusions: Hostile individuals with Type 2 diabetes may be susceptible to stress-induced increases in inflammation. Further research is needed to understand if such changes increase the risk of cardiovascular disease in this population.

Purpose: The hardware and software of a novel wavefront sensor was developed (The sensor presented here is patent pending.). It has the same principal of the Hartmann-Shack (HS) and other sensors that are based on slope information for recovery of wavefront surface, but a different symmetry, and does not use individual microlenses. This polar symmetry might offer differences during practical measurements that may add value to current and well-established "gold standard" techniques., Methods: The sensor consists of a set of concentric "half-donut" surfaces (longitudinally sectioned toroids) molded on an acrylic surface with a CCD located at the focal plane. When illuminated with a plane wavefront, it focuses a symmetric pattern of concentric discs on the CCD plane; for a distorted wavefront, a nonsymmetric disc pattern is formed (similar to images of a placido-based videokeratographer). From detection of shift in the radial direction, radial slopes are computed for a maximum of 2880 points, and the traditional least-squares procedure is used to fit these partial derivatives to a set of 15 conventional OSA-VSIA Zernike polynomials. Theoretical computations for several synthetic surfaces containing low-order aberration (LOA) and high-order aberration (HOA) were implemented for both the HS and the new sensor., Results: Root mean square error (RMSE) in microns when theoretical data was taken as control, for HS sensor and new sensor, was 0.02 and 0.00003 for LOA (defocus, astigmatism) and 0.07 and 0.06 for HOA (coma, spherical, and higher terms), respectively. After this, practical preliminary measurements on a mechanical eye with a 5-mm pupil and 10 different defocus aberrations ranging from -5 D to 5 D, in steps of 1 D, were compared between sensors. RMSE for difference in measurements for HS and new sensor for sphere, cylinder, and axis, was 0.13 D, 0.07 D, and 11. Measurements were taken only on defocus aberrations. Qualitative images for astigmatism are shown., Discussion: Although practical in vivo tests were not conducted in this first study, we also discuss certain possible alignment differences that may arise as a result of the different symmetry of the new sensor. To take any conclusive assumption regarding the accuracy and/or precision of this new sensor, when compared with other well-established sensors, statistically significant in vivo measurements will need to be conducted.

Purpose: Our main goal in this work was to develop an artificial neural network (NN) that could classify specific types of corneal shapes using Zernike coefficients as input. Other authors have implemented successful NN systems in the past and have demonstrated their efficiency using different parameters. Our claim is that, given the increasing popularity of Zernike polynomials among the eye care community, this may be an interesting choice to add complementing value and precision to existing methods. By using a simple and well-documented corneal surface representation scheme, which relies on corneal elevation information, one can generate simple NN input parameters that are independent of curvature definition and that are also efficient., Methods: We have used the Matlab Neural Network Toolbox (MathWorks, Natick, MA) to implement a three-layer feed-forward NN with 15 inputs and 5 outputs. A database from an EyeSys System 2000 (EyeSys Vision, Houston, TX) videokeratograph installed at the Escola Paulista de Medicina-Sao Paulo was used. This database contained an unknown number of corneal types. From this database, two specialists selected 80 corneas that could be clearly classified into five distinct categories: (1) normal, (2) with-the-rule astigmatism, (3) against-the-rule astigmatism, (4) keratoconus, and (5) post-laser-assisted in situ keratomileusis. The corneal height (SAG) information of the 80 data files was fit with the first 15 Vision Science and it Applications (VSIA) standard Zernike coefficients, which were individually used to feed the 15 neurons of the input layer. The five output neurons were associated with the five typical corneal shapes. A group of 40 cases was randomly selected from the larger group of 80 corneas and used as the training set., Results: The NN responses were statistically analyzed in terms of sensitivity [true positive/(true positive + false negative)], specificity [true negative/(true negative + false positive)], and precision [(true positive + true negative)/total number of cases]. The mean values for these parameters were, respectively, 78.75, 97.81, and 94%., Conclusion: Although we have used a relatively small training and testing set, results presented here should be considered promising. They are certainly an indication of the potential of Zernike polynomials as reliable parameters, at least in the cases presented here, as input data for artificial intelligence automation of the diagnosis process of videokeratography examinations. This technique should facilitate the implementation and add value to the classification methods already available. We also discuss briefly certain special properties of Zernike polynomials that are what we think make them suitable as NN inputs for this type of application.

Advances in excimer laser spot size and ablation pattern capabilities, together with the development of Hartmann-Shack sensors for high-resolution eye aberration measurements, have taken refractive surgery to a new stage. Nevertheless, studies have shown that the lens contributes differently to total aberration and depends on accommodation and age factors. Therefore, the choice of which aberrations to correct is also related to the internal optics of the eye, although only the cornea undergoes surface changes. A simple model is to subtract the total aberrations of the eye from the aberrations of only the cornea, which are calculated based on its three-dimensional profile. This has been done successfully, in practice, for certain commercial videokeratographs (VKS), but it is important to analyze the consequences of general flaws associated with VKS systems when used to estimate the corneal aberrations. A computer simulation of Placido-based VKS has been developed and applied to several theoretical surfaces resembling corneal profiles. The resulting Placido images were used to retrieve the corneal profiles. Corneal surface data were input into an algorithm that calculates the wave-front aberration as the difference in optical path length of the principal ray of an on-axis object point and several marginal rays. Wave aberration was then fit by a set of Zernike polynomials using the least-square method. From the Zernike coefficients, the correlation of different corneal profiles to their optical aberrations could be estimated. Misalignment (decentralization), improper focusing, and tilt were also implemented to the VKS simulation, and a quantitative analysis of the consequences on precision of wave aberration estimation was undertaken.