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1.
Catheter ablation is currently the only curative treatment for scar-related ventricular tachycardias (VTs). However, not only are ablation procedures long, with relatively high risk, but success rates are punitively low, with frequent VT recurrence. Personalized in-silico approaches have the opportunity to address these limitations. However, state-of-the-art reaction diffusion (R-D) simulations of VT induction and subsequent circuits used for in-silico ablation target identification require long execution times, along with vast computational resources, which are incompatible with the clinical workflow. Here, we present the Virtual Induction and Treatment of Arrhythmias (VITA), a novel, rapid and fully automated computational approach that uses reaction-Eikonal methodology to induce VT and identify subsequent ablation targets. The rationale for VITA is based on finding isosurfaces associated with an activation wavefront that splits in the ventricles due to the presence of an isolated isthmus of conduction within the scar; once identified, each isthmus may be assessed for their vulnerability to sustain a reentrant circuit, and the corresponding exit site automatically identified for potential ablation targeting. VITA was tested on a virtual cohort of 7 post-infarcted porcine hearts and the results compared to R-D simulations. Using only a standard desktop machine, VITA could detect all scar-related VTs, simulating activation time maps and ECGs (for clinical comparison) as well as computing ablation targets in 48 minutes. The comparable VTs probed by the R-D simulations took 68.5 hours on 256 cores of high-performance computing infrastructure. The set of lesions computed by VITA was shown to render the ventricular model VT-free. VITA could be used in near real-time as a complementary modality aiding in clinical decision-making in the treatment of post-infarction VTs. 相似文献
2.
《Acta histochemica》2022,124(2):151860
Objective To explore the preliminary application method and diagnostic value of virtual touch tissue imaging quantification (VTIQ) in diffuse testicular diseases of male infertility. A total of 70 male examiners in our hospital from June 2019 to March 2020 were selected as the research objects. According to whether the subjects are sick (testicular microlithiasis, varicocele), all subjects are divided into three groups: normal group, testicular microlithiasis group, and varicocele group. Whether there is a difference between the groups, and analyze whether there is a correlation between the index reflecting the quality of the semen and the testicular shear wave velocity. The measurement of different positions in the testis will affect the magnitude of the shear wave velocity (P < 0.05). The shear wave velocities of the testes of different diseases are obviously different from the normal side. At the same time, postural changes will have a certain impact on the shear wave velocities of both testes (all P < 0.05). There is a certain correlation between the testicular shear wave velocity and the conventional semen quality index (total sperm motility (P < 0.05)) of the subjects. Acoustic palpation tissue imaging quantitative technology can be applied to the diagnosis of male testes and testicular-related diseases (especially diffuse testicular diseases), and is more suitable for male infertility, which can provide clinical diagnosis and treatment options certain imaging basis. 相似文献
3.
目的:观察银杏叶胶囊对脑卒中后轻度认知障碍患者认知功能及预后的影响。方法:选择100例脑卒中后轻度认知障碍患者,按随机数字表法分为观察组和对照组各50例。对照组给予西医对症治疗,观察组在对照组基础上给予银杏叶胶囊治疗。比较2组治疗前后蒙特利尔认知评估量表(MoCA)评分、脑部动脉血流速度、脑动脉硬化发生率、血管痉挛发生率以及血管狭窄发生率。结果:治疗前,2组MoCA评分比较,差异无统计学意义(P>0.05)。治疗后,2组MoCA评分均较治疗前升高(P<0.05),且观察组MoCA评分高于对照组(P<0.05)。治疗后,观察组大脑前动脉(ACA)、大脑中动脉(MCA)、大脑后动脉(PCA)、椎动脉(VA)、基底动脉(BA)的血流速度明显快于对照组(P<0.05)。治疗后,观察组脑动脉硬化发生率、血管痉挛发生率以及血管狭窄发生率均低于对照组(P<0.05)。结论:银杏叶胶囊可以改善脑卒中后轻度认知障碍患者的认知功能和脑部血流,降低血管狭窄发生率,临床疗效较好。 相似文献
4.
《Clinical neurophysiology》2021,132(4):967-974
ObjectiveChronic fatigue syndrome (CFS) and fibromyalgia (FM) are disorders of unknown etiology and unclear pathophysiology, with overlapping symptoms of – especially muscular –fatigue and pain. Studies have shown increased muscle fiber conduction velocity (CV) in the non-painful muscles of FM patients. We investigated whether CFS patients also show CV abnormalities.MethodsFemales with CFS (n = 25), with FM (n = 22), and healthy controls (n = 21) underwent surface electromyography of the biceps brachii, loaded up to 20% of maximum strength, during short static contractions. The mean CV and motor unit potential (MUP) velocities with their statistical distribution were measured.ResultsThe CV changes with force differed between CFS-group and both FM-group and controls (P = 0.01). The CV of the CFS-group increased excessively with force (P < 0.001), whereas that of the controls increased only slightly and non-significantly, and that of the FM-group did not increase at all. In the CFS-group, the number of MUPs conveying very high conduction velocities increased abundantly with force and the MUPs narrowed.ConclusionOur results suggest disturbed muscle membrane function in CFS patients, in their motor units involved in low force generation. Central neural deregulation may contribute to this disturbance.SignificanceThese findings help to detangle the underlying mechanisms of CFS. 相似文献
5.
《Gait & posture》2021
BackgroundIndividuals with lower limb amputation are routinely assessed with a variety outcome measures, however there is a lack of published data to indicate minimal clinically important differences (MCID) for many of these outcome measures. Three such important gait-specific outcome measures include walking velocity, gait profile score (GPS) and the two minute walk test (2MWT).Research questionDetermine the MCIDs for walking velocity, GPS and 2MWT for individuals with lower limb amputation.MethodsWalking velocity and GPS (n = 60), and 2MWT (n = 119) data for individuals with unilateral transfemoral or knee disarticulation were identified retrospectively from a database held at the study centre. An anchor-based method was used with Medicare functional classification level (MFCL) acting as the impairment-related criterion, and a least-squares linear regression approach was used to calculate the gradient required for a change between MFCL levels.ResultsAn increase of 0.21 m/s (95 % CI: 0.13,0.29) for walking velocity, a reduction of 1.7° (95 % CI: -2.449,-1.097) for GPS and an increase of 37.2 m (95 % CI: 28.8,45.5) for 2MWT were found to correspond to an increase in MFCL of one level. Walking velocity, GPS and 2MWT correlated with MFCL with R2 values of 0.333, 0.322 and 0.398 respectively (p < 0.00001). The authors propose that 0.21 m/s for walking velocity, 1.7° for GPS and 37.2 m for 2MWT be used as MCID values for individuals with lower limb amputation.SignificanceThe results of this study can be used to help both researchers and clinicians to objectively evaluate if interventions for individuals with lower limb amputation are effective. 相似文献
6.
目的:探索加味大黄?虫颗粒对精索静脉曲张模型大鼠精子线粒体结构的影响。方法:40只雄性大鼠随机选出10只作为假手术组,剩余30按照Turner方法制造左侧精索静脉曲张模型大鼠,造模完成后,按照随机数字表法分为加味大黄?虫颗粒组、模型组、迈之灵组,每组各10只。加味大黄?虫颗粒组给予加味大黄?虫颗粒灌胃; 迈之灵组予迈之灵片,假手术组和模型组分别予等剂量0.9%生理盐水灌胃。8周后处死所有大鼠,取出左侧睾丸组织,完成精液质量分析、睾丸组织病理检测。结果:灌胃8周后,加味大黄?虫颗粒组精子浓度、总活率、前向运动精子、精子直线速度(VSL)、精子曲线速度(VCL)、平均路径速度(VAP)、精子头侧摆幅度(ALH),明显高于模型组(P<0.05)。模型组睾丸组织病理报告生精小管管腔空化,各级生精细胞破坏严重,精子膜结构破坏,精子线粒体肿胀、溶解。而加味大黄?虫颗粒组中睾丸组织的病理损伤得到不同程度的改善,精子线粒体结构完整,形态大小规则。结论:加味大黄?虫颗粒在一定程度上修复精索静脉曲张大鼠睾丸组织的病理损伤,进而起到保护精子线粒体结构与功能的作用,为精子的发育、活动提供稳定的能量代谢环境,有助提高精子活力及增加受精能力。 相似文献
7.
8.
There is evidence that serum 25-hydroxyvitamin D [25-(OH) D] levels may be associated with cardiovascular disease and its risk factors. This study aimed to investigate the relationship between 25-(OH) D levels and blood pressure (BP), blood lipids, and arterial elasticity in middle-aged and elderly cadres in China.In this retrospective study, we included 401 civil servants and cadres aged >42 years who underwent medical examinations at Guiyang Municipal First People''s Hospital, China in 2018. The participants were assigned to deficiency (≤20 ng/mL), insufficiency (20–30 ng/mL), and sufficiency (≥30 ng/mL) groups according to 25-(OH) D levels in their blood. Demographics, brachial–ankle pulse wave velocity (baPWV), BP, ankle–brachial index (ABI), and blood lipids were compared among groups. The associations between 25-(OH) D and other parameters were evaluated using linear regression analysis.Median (range) 25-(OH) D levels in the deficiency (n = 162), insufficiency (n = 162), and sufficiency (n = 77) groups were 15.32 (2.93–19.88), 25.12 (20.07–29.91), and 33.91 (30.23–82.42) ng/mL, respectively. There were significant differences in systolic BP, pulse pressure, baPWV (left and right sides), ABI (left side), high-density lipoprotein-cholesterol, and triglycerides (TGs; all P < .05) among groups. Multivariate linear regression revealed that TG, left baPWV, and right baPWV were significantly negatively correlated with 25-(OH) D levels (all P < .05).In this study, 25-(OH) D levels were found to be associated with TG, left baPWV, and right baPWV values. 25-(OH) D deficiency may be associated with reduced arterial elasticity. 相似文献
9.
Jacob C. Jentzer Brandon M. Wiley Nandan S. Anavekar Sorin V. Pislaru Sunil V. Mankad Courtney E. Bennett Gregory W. Barsness Steven M. Hollenberg David R. Holmes Jae K. Oh 《JACC: Cardiovascular Imaging》2021,14(2):321-332
ObjectivesThis study sought to define the 2-dimensional and Doppler echocardiographic hemodynamics associated with each Society for Cardiovascular Angiography and Interventions (SCAI) stage, and to determine their association with mortality.BackgroundThe SCAI shock stages classification stratifies mortality risk in cardiac intensive care unit (CICU) patients, but the echocardiographic and hemodynamic parameters that define these SCAI shock stages are unknown.MethodsUnique CICU patients admitted from 2007 to 2015 who had a transthoracic echocardiogram within 1 day of CICU admission were included. Echocardiographic variables were evaluated as a function of SCAI shock stage. Multivariable logistic regression determined the association between echocardiographic parameters with adjusted hospital mortality.ResultsWe included 5,453 patients with a median age of 69.3 years (interquartile range: 58.2 to 79.0 years) (37% women), and a median left ventricular ejection fraction (LVEF) of 50% (interquartile range: 35% to 61%). Higher SCAI shock stages were associated with lower LVEF and worse systemic hemodynamics. Hospital mortality was higher in patients with LVEF <40%, cardiac index <1.8 l/min/m2, stroke volume index <35 ml/m2, cardiac power output <0.6 W, or medial early mitral valve inflow velocity to early diastolic annular velocity (E/e′) ratio >15 (particularly in SCAI shock Stages A to C). After multivariable adjustment, only stroke volume index <35 ml/m2 (adjusted odds ratio: 2.0; 95% confidence interval: 1.4 to 3.0; p < 0.001) and E/e′ ratio >15 (adjusted odds ratio: 1.52; 95% confidence interval: 1.04 to 2.23; p = 0.03) remained associated with higher hospital mortality.ConclusionsNoninvasive 2-dimensional and Doppler echocardiographic parameters correlate with the SCAI shock stages and improve risk stratification for hospital mortality in CICU patients. Low stroke volume index and high E/e′ ratio demonstrated the strongest association with hospital mortality. 相似文献
10.
探讨血尿酸水平与超极速脉搏波传导速度(ufPWV)的相关性及其在性别间的差异。方法 选取2016年3月~2020年12月在南京中医药大学附属医院体检人群130例,具有动脉粥样硬化危险因素患者226例,共356例,分别根据男女血尿酸水平的四分位数将全部人群分为Q1、Q2、Q3、Q4共4组。利用ufPWV技术检测颈动脉收缩起始脉搏波速度(PWV-BS)和收缩末期脉搏波速度(PWV-ES)。比较不同尿酸水平间及男性女性间PWV-BS、PWV-ES差异。分析血尿酸水平与年龄、BMI、eGFR等临床资料间的相关性。应用Logistic回归分析血尿酸水平与ufPWV增高的关系。结果 随着血尿酸水平增高,年龄、BMI、TC、Scr、PWV-ES及高血压患病率显著增高, eGFR、HDL显著降低。男性血尿酸、PWV-BS及PWV-ES均显著高于女性(P分别为<0.001、0.0024、0.0018),男性血尿酸与PWV-BS、PWV-ES均不相关,女性血尿酸仅与PWV-ES呈正相关(r=0.265,P<0.05)。男性与女性血尿酸均与BMI、TC、Scr成显著正相关,与HDL、eGFR成显著负相关,并且女性相关程度大于男性。Logistic回归显示以Q1组为对照,在矫正了年龄、BMI 、SBP、DBP、TC、TG、HDL、LDL、FBG、Scr、吸烟、高血压、糖尿病等混杂因素后,血尿酸Q4组可独立于上述因素成功预测PWV-ES增高的风险,女性(OR:5.15,95% CI:1.20~22.10,P=0.027),全体人群(OR:2.41,95% CI:1.42~5.69,P=0.042),但该因子预测价值不能独立于eGFR而存在。结论 血尿酸可间接反应动脉硬化的进展,同时PWV-ES可作为血尿酸对血管功能损伤早期无创性评估的指标;血尿酸是女性动脉粥样硬化的独立危险因素,但其预测价值具有一定的eGFR依赖性。 相似文献