Annular versus supra-annular sizing for transcatheter aortic valve replacement in bicuspid aortic valve disease

BackgroundCT measurement of supra-annular area (SA) has been proposed as an alternative to annular area (AA) for sizing of trancatheter valves in biscuspid aortic valves (BAV). This study examines the reproducibility of SA and AA measurements and their potential impact on downstream transcatheter heart valve sizing and clinical outcomes.Methods44 consecutive patients (mean age: 73 ± 15 years, 57% male) undergoing CTA with subsequent SAPIEN 3 valve insertion for severe bicuspid aortic stenosis (AS) were included. AA was measured at the basal ring. SA was measured by generating a circle defined by the intercommisural distance. AA and SA were measured by 2 independent observers. Baseline characteristics, TAVR procedural data, and discharge echocardiography data were collected.ResultsThe SA was significantly larger than the AA (562 ± 146mm2 vs. 518 ± 112mm2,p = 0.013). Interobserver agreement was high using both techniques (ICC AA = 0.98,p < 0.001; SA = 0.80,p < 0.001), but with narrower limits of agreement with AA measurements (mean difference (limits of agreement): AA = −3mm2 (22; 19), SA = −16mm2 (−92; 76)). AA-based device sizing demonstrated substantial agreement with final valve inserted (κ = 0.72,p < 0.001), while SA demonstrated fair agreement (κ = 0.40,p < 0.001). There was no difference in post TAVR gradients, paravalvular leakage or valve success between patients with concordant sizing between AA and SA, and those in whom SA would have suggested an alternate valve size.ConclusionsSupra-annular sizing is less reproducible than annular sizing, with no difference in procedural complication rates in patients in whom supra-annular sizing would have altered the device size used. These results suggest no role for supra-annular sizing in current clinical practice.     

In utero DDT exposure and breast density before age 50

Prior studies in the Child Health and Development Studies (CHDS) found in utero exposure to the pesticide, dichlorodiphenyltrichloroethane (DDT), increased breast cancer risk by age 52. Mammographic density is considered a primary risk factor for breast cancer. We conducted a study of 309 daughters from the CHDS to examine in utero DDT exposure and mammographic density in midlife. Among daughters with high (>75th percentile) exposure to p,p’-Dichlorodiphenyldichloroethylene (DDE), p,p’-DDT was significantly correlated with increased dense area and percent density regardless of her body mass in midlife. In the subset of women with lower (<75th percentile) p,p-DDE, p,p’-DDT was associated with increased non-dense breast area. This was explained by adjustment for midlife BMI suggesting that p,p’-DDT may be obesogenic. In aggregate our findings indicate that early life p,p’-DDT exposure impacts breast density in a complex way that depends on the hosts biological ability to sequester and process DDT and levels of exposure.     

人工智能在医学领域应用浅析

医疗与人工智能相结合,是医学发展的重要方向。作者综述了人工智能在诊断、治疗、预防、科研、教学等医学领域的应用情况,分析了人工智能发展面临的问题和挑战,对人工智能的应用前景进行了展望。     

新冠肺炎疫情下我国农村基层卫生防控能力建设分析

在新冠肺炎的疫情防控中,基层医疗卫生机构对社区防控和关口前移产生重要基础作用。但针对农村基层而言,还存在着人员结构老化、人员素质较低、防控意识不足、信息化基础薄弱等问题。为进一步推动我国农村基层卫生防控能力建设,未来建议加大专业人才队伍建设、将公共卫生机构纳入县域医共体网络、完善农村联防联控体系建设、建立健全信息化互联互通平台、加强对群众的健康教育与宣传、促进地方典型经验的交流。