原发性高血压患者动态脉压对心脏、血肌酐及颈动脉的影响

目的 通过对原发性高血压(EH)患者动态脉压的临床资料分析,探讨动态脉压对心脏、血肌酐及颈动脉的影响.方法 对EH患者183例进行24 h无创动态血压监测,按动态脉压分为脉压<60 mmHg(1 mmHg=0.133 kPa)组61例,60～80 mmHg组75例,>80 mmHg组47例.所有入选患者行以下检查:血肌酐、心电图、超声心动图、颈动脉超声,24 h动态血压.结果 脉压>80 mmHg组颈动脉斑块指数、左心室质量指数、左心室舒张末径及血肌酐均高于其他两组;脉压60～80 mmHg次之;提示颈动脉内膜厚度、左心室肥厚及血肌酐与脉压显著相关.结论 EH患者心脏、肾脏及颈动脉损害与增大的脉压有关,脉压是左心室肥厚和颈动脉内膜增厚的预测危险因素.     

原发性高血压患者动态脉压对心脏、血肌酐及颈动脉的影响

目的通过对原发性高血压(EH)患者动态脉压的临床资料分析,探讨动态脉压对心脏、血肌酐及颈动脉的影响。方法对 EH 患者183例进行24 h 无创动态血压监测,按动态脉压分为脉压<60 mmHg(1 mmHg=0.133 kPa)组61例,60～80 mmHg 组75例,>80 mmHg 组47例。所有人选患者行以下检查:血肌酐、心电图、超声心动图、颈动脉超声、24 h 动态血压。结果脉压>80 mmHg 组颈动脉斑块指数、左心室质量指数、左心室舒张末径及血肌酐均高于其他两组;脉压60～80 mmHg 次之;提示颈动脉内膜厚度、左心窒肥厚及血肌酐与脉压显著相关。结论 EH 患者心脏、肾脏及颈动脉损害与增大的脉压有关,脉压是左心室肥厚和颈动脉内膜增厚的预测危险因素。     

老年原发性高血压患者动态脉压与靶器官损害的相关性研究

目的通过对老年原发性高血压患者临床资料分析,探讨老年原发性高血压患者动态脉压与靶器官损害的关系.方法入选老年原发性高血压患者96例,按动态脉压分为脉压40～60mmHg(1 mmHg=0.133kPa)组45例和脉压＞60mmHg组51例.对入选患者做以下检查心电图、超声心动图、24小时动态血压、头颅计算机断层摄影术、颈动脉超声,并查血肌酐、尿白蛋白.结果脉压＞60mmHg组左心室重量指数、颈动脉内膜厚度、尿白蛋白定量、左心室舒张末期内径、颈动脉斑块指数均高于脉压40～60mmHg组(P＜0.05～0.01),靶器官损害发生率高于脉压40～60mmHg组(P均＜0.05);直线相关分析示颈动脉内膜厚度与收缩压、脉压、脉压变异相关.左心室重量指数与收缩压、收缩压变异、舒张压、脉压、脉压变异相关;多因素逐步回归分析得到逐步回归方程,提示颈动脉内膜厚度与脉压呈正相关,左心室重量指数与脉压及脉压变异成正相关.结论老年原发性高血压患者靶器官损害与增大的脉压有关,脉压是颈动脉内膜增厚和左心室肥厚的危险因素之一.     

老年原发性高血压患者动态脉压与左室质量指数的相关性

目的研究老年原发性高血压患者动态脉压与左室质量指数（LVMI）的相关性。方法选择153例老年原发性高血压患者,均行24h动态血压监测,根据平均脉压（ABPP）分为≥60mmHg组和〈60mmHg组,采用多普勒超声心动图测量室间隔厚度、左室后壁厚度及左室舒张末内径,并计算LVMI,将两组的临床资料进行分析。结果≥60mmHg组24h平均收缩压、日间平均收缩压、夜间平均收缩压、日间平均收缩压负荷值、夜间平均收缩压负荷值、24h平均收缩压负荷值及LVMI明显高于ABPP〈60mmHg组;24hABPP增大,与LVMI呈显著正相关（r=0．949,P=0．00）。结论脉压增大与LVMI呈显著正相关,治疗老年原发性高血压时,不仅要控制血压在理想水平,还要尽可能缩小脉压。     

老年高血压病病人脉压与靶器官损害的关系

目的探讨脉压(PP)与高血压病靶器官损害的关系.方法 120例药物规则治疗下的老年高血压病病人,根据脉压水平的不同,分为PP＜60 mmHg和PP≥60 mmHg两组,颈动脉超声检测颈动脉粥样斑块发生率(CAPR)、颈总动脉内膜中层厚度(IMT)及内径(LD),超声心动图检测主动脉根部内径(AOD)、左心房内径(LAD)、左心室重量指数(LVMI)、左心室射血分数(LVEF)、左心房收缩期充盈峰值流速与左心室舒张早期充盈峰值流速比值(A/E),生化测定血清尿素氮(BUN)、肌酐(Scr)、内生肌酐清除率(Ccr).评价不同脉压水平的靶器官损害.结果与PP＜60 mmHg组比较,PP≥60 mmHg组CAPR、IMT、LD、AOD、LAD、LVMI、A/E、BUN、Scr均显著升高(P＜0.05),LVEF、Ccr均显著降低(P＜0.05).结论老年高血压病病人脉压增大,可促进心脏、血管及肾脏等靶器官损害,控制脉压可以减轻靶器官损害程度.     

老年人高血压患者脉压与左室肥厚的临床探讨

目的探讨老年高血压患者24h脉压(PP)与左心室肥厚的关系。方法对175例老年高血压患者分别用动态血压记录仪监测动态血压,根据血压检测结果按24h平均脉压(ABPP)分为≥60mmHg组和<60mmHg组,采用多普勒超声心动图(UCG)测量左室内径(EDd),室间隔厚度(IVST),左室后壁厚度(LVPWT),计算射血分数(EF)、左室重量(LVM)及重量指数(LVMI),并将两组年龄、性别及发生室性心律失常、心力衰竭的临床资料进行分析。结果(1)在年龄、性别上两组差异无显著意义。(2)ABPP≥60mmHg组的LVMI及影响LVMI的3大因素EDd、IVST、LVPWT的值高于ABPP<60mmHg组,EF则低于<60mmHg组(P<0.01)。(3)对两组发生室性心律失常、心力衰竭的例数有显著性意义(P<0.01)。结论老年人24h平均脉压增大与左心室肥厚呈正相关,易发生左心室肥厚、室性心律失常及心力衰竭,有一定的临床意义。     

老年原发性高血压患者脉压与靶器官损害的相关性研究

目的探讨老年原发性高血压患者脉压与靶器官损害的严重程度及其相关性.方法将98例老年原发性高血压患者分为脉压＜60mm Hg和脉压≥60mmHg两组,均做心电图、超声心动图、头颅CT、颈动脉超声,血尿素氮（BUN）、血肌酐（Cr）、尿肌酐和尿白蛋白检查.结果脉压≥60 mm Hg组与脉压＜60 mm Hg组比较,其左心室重量指数（LVMI）、左心室舒张末期内径（LVDd）、颈动脉内膜厚度（IMT）、颈动脉斑块发生率（CAPR）、BUN、Cr、尿白蛋白定量等指标均高于脉压＜60 mm Hg组（P＜0.05）,靶器官损害发生率高于脉压＜60 mm Hg组（P均＜0.05）.结论老年原发性高血压患者靶器官损害与增大的脉压有关,控制脉压可以减轻靶器官损害程度.     

老年高血压病患者高脉压与靶器官损害

目的观察在药物规则治疗下的老年高血压病患者脉压(PP)与心脏、血管和肾脏等靶器官损害的关系,为临床更好地控制血压,防治靶器官损害提供依据.方法用24小时动态血压仪监测263例老年高血压病患者全天平均脉压(ABPP),多普勒超声检查颈动脉粥样斑块发生率(CAPR)、颈总动脉分叉处内膜-中膜厚度(IMT)及内径(CAD)、左室重量指数(LVMI)、左室舒张早期充盈峰值流速与心房收缩期充盈峰值流速比值(E/A值)、射血分数(EF),生化测定内生肌酐清除率(Ccr)及24小时尿微量白蛋白排泄量(MAU).评价不同ABPP值对心脏、颈动脉、肾脏结构或功能的影响.结果老年高血压病患者PP≥60 mmHg与P\%P\%<60 mmHg比较,E/A值、EF和Ccr均下降(P<0.05),而LVMI、CAD、CAPR、IMT、MAU升高(P<0.05).结论老年高血压病患者脉压增大,可促进心脏、血管及肾脏等靶器官损害,提示在老年高血压病患者中脉压也是预测心脏、血管及肾脏损害有价值的指标,控制脉压可以减轻老年高血压病患者靶器官损害.     

原发性高血压患者动态脉压与靶器官损害的关系

对183例原发性高血压患者行24 h无创动态血压监测,按动态脉压分为A组(脉压＜60 mmHg)61例、B组(脉压60～80眦Hg)75例、C组(脉压＞80mmHg)47例,分别行血肌酐、心电图、超声心动图、颈动脉超声检查.发现C组患者左心室重量指数、颈动脉斑块指数、左心室舒张末径均高于其他两组,靶器官损害发生率最高.认为脉压增大是左心室肥厚和颈动脉内膜增厚的危险因素.     

高血压左心室肥厚与脉压关系的临床观察

目的　探讨高血压病（essentialhypertension,EH）左心室肥厚（leftventricularhypertrophy,LVH)与脉压（pulsepressure,PP)和大动脉内径变化的关系。方法　应用诊所血压测量和超声心动图检查,测量并计算92例高血压患者脉压,左室重量指数及大动脉内径。分左室肥厚组和无左室肥厚组,分别进行统计学比较。结果　脉压和主动脉根部内径在高血压左室肥厚组和无左室肥厚组之间均有显著性差异（P<0.01）,左室重量指数与脉压（r=0.3,P<0.01）和主动脉根部内径（r=0.5,P<0.01)之间存在一定的正相关。结论　脉压和大动脉内径增大,提示大动脉顺应性下降,在高血压左室肥厚中起重要作用。     

Change of bilateral difference in radial artery pulse morphology with one-side arm movement

Previous studies have demonstrated that the compliance of peripheral artery changes with arm movement. This study aimed to quantify the bilateral difference in radial artery pulse morphology with one-side arm movement. Twenty-four healthy subjects were recruited. Radial artery pulses were synchronously recorded from both arms, with one arm (left or right) at five different positions (90°, 45°, 0°, −45° and −90°) and the other arm at horizontal level (0°) as reference. Two types of indices of arterial pulse morphology were derived from the normalized arterial pulse signals: the waveform width corresponding to the 50%, 60% and 70% pulse amplitude (W₅₀, W₆₀, W₇₀) and the total area of normalized pulse waveform (A_pulse). No matter whether the moving arm was left or right arm, when compared with the other side reference arm, all the waveform widths decreased with arm moving from 90°, 45°, 0°, −45°, and −90°. The bilateral difference of W₅₀, W₆₀ and W₇₀ with the moving arm (either left or right) at 90°, 45° were significantly positive (both p < 0.01) and significantly negative at −90° (both p < 0.05). Meanwhile, no matter whether the moving arm is left or right, A_pulse decreased with arm moving from 90°, 45°, 0°, −45°, and −90°. The bilateral difference of A_pulse with the left moving arm were significantly positive at 45°, 90° (both p < 0.05). Meanwhile, the bilateral difference of A_pulse from the moving right arm was significantly positive at 90° and significantly negative at −45° and −90° (all p < 0.05). In summary, this study quantified the bilateral arterial pulse morphology between arteries with different compliances induced by a simple arm positioning procedure.     

中心脉压水平与颈动脉粥样硬化狭窄程度的相关性研究

目的:探讨脉压、收缩压、舒张压水平与颈动脉粥样硬化(CAS)狭窄程度的关系。方法:对80例入选病例均行彩色多普勒超声测定颈总动脉内中膜厚度及斑块积分,根据颈动脉超声结果将患者分为斑块组、非斑块组,测量中心及外周收缩压、舒张压及脉压,应用统计学方法评定其与CAS的关系。结果:斑块组脉压显著高于非斑块组(P<0.01),CAS发生率在脉压≥50mmHg(1mmHg=0.133kPa)患者显著高于脉压<50mmHg患者(P<0.01),多元线性回归分析表明脉压是CAS发生发展的独立危险因素,且中心脉压较肱动脉脉压预测心血管事件的危险性更好。结论:中心脉压可作为CAS狭窄程度的高危预测指标之一。     

Arterial stiffness is associated with increase in blood pressure over time in treated hypertensives

Arterial stiffness is associated with incident hypertension. We hypothesized that measures of arterial stiffness would predict increases in systolic (SBP), mean (MAP), and pulse pressure (PP) over time in treated hypertensives. Blood pressure (BP) was measured a mean of 8.5 ± 0.9 years apart in 414 non-Hispanic white hypertensives (mean age, 60 ± 8 years; 55% women). The average of three supine right brachial BPs was recorded. Measures of arterial stiffness, including carotid-femoral pulse wave velocity (cfPWV), aortic augmentation index (AIx), and central pulse pressure (CPP), were obtained at baseline by applanation tonometry. We performed stepwise multivariable linear regression analyses adjusting for potential confounders to assess the associations of arterial stiffness parameters with BP changes over time. SBP, MAP, and PP increased in 80% of participants. After adjustment for covariates listed, cfPWV (m/s) was associated with increases in SBP (β ± standard error [SE], 0.71 ± 0.31) and PP (β ± SE, 1.09 ± 0.27); AIx (%) was associated with increases in SBP (β ± SE, 0.23 ± 0.10) and MAP (β ± SE, 0.27 ± 0.07); and CPP (mmHg) was associated with increases in SBP (β ± SE, 0.44 ± 0.07), MAP (β ± SE, 0.24 ± 0.05), and PP (β ± SE, 0.42 ± 0.06) over time (P ≤ .02 for each). In conclusion, arterial stiffness measures were associated with longitudinal increases in SBP, MAP, and PP in treated hypertensives.     

Spatial Decomposition of a Broadband Pulse Caused by Strong Frequency Dispersion of Sound in Acoustic Metamaterial Superlattice

An acoustic metamaterial superlattice is used for the spatial and spectral deconvolution of a broadband acoustic pulse into narrowband signals with different central frequencies. The operating frequency range is located on the second transmission band of the superlattice. The decomposition of the broadband pulse was achieved by the frequency-dependent refraction angle in the superlattice. The refracted angle within the acoustic superlattice was larger at higher operating frequency and verified by numerical calculated and experimental mapped sound fields between the layers. The spatial dispersion and the spectral decomposition of a broadband pulse were studied using lateral position-dependent frequency spectra experimentally with and without the superlattice structure along the direction of the propagating acoustic wave. In the absence of the superlattice, the acoustic propagation was influenced by the usual divergence of the beam, and the frequency spectrum was unaffected. The decomposition of the broadband wave in the superlattice’s presence was measured by two-dimensional spatial mapping of the acoustic spectra along the superlattice’s in-plane direction to characterize the propagation of the beam through the crystal. About 80% of the frequency range of the second transmission band showed exceptional performance on decomposition.     

Surface Roughness Analysis of H13 Steel during Electrical Discharge Machining Process Using Cu–TiC Sintered Electrode

In electrical discharge machining (EDM), the machined surface quality can be affected by the excessive temperature generation during the machining process. To achieve a longer life of the finished part, the machined surface quality plays a key role in maintaining its overall integrity. Surface roughness is an important quality evaluation of a material’s surface that has considerable influence on mechanical performance of the material. Herein, a sintered cermet tooltip with 75% copper and 25% titanium carbide was used as tool electrode for processing H13 steel. The experiments have been performed to investigate the effects of EDM parameters on the machined surface roughness. The findings show that, as the pulse current, pulse length, and pulse interval are increased, the surface roughness tends to rise. The most significant determinant for surface roughness was found to be pulse current. A semi-empirical surface roughness model was created using the characteristics of the EDM technique. Buckingham’s theorem was used to develop a semi-empirical surface roughness prediction model. The semi-empirical model’s predictions were in good agreement with the experimental studies, and the built empirical model based on physical features of the cermet tooltip was tested using dimensional analysis.     

Standard Terminologies for Photoplethysmogram Signals

Photoplethysmography is one of the optical techniques has been developed for experimental use in vascular disease. It has several advantages over other traditional experimental approaches. Because of its non-invasive, safe, costeffective and easy-to-use properties, it is considered as a useful diagnostic tool. The further developments in the Photoplethysmograph may replace it among other tools used in the assessment of vascular diseases such as blood test and ultrasound. This overview discusses the different terminologies used for the photoplethysmograph and reveals the research discontinuity among different disciplines. Moreover, it suggests standard terminologies as a resolution for a confusion persisted for more than 50 years.     

Relationship between brachial‐ankle pulse wave velocity and invasively measured aortic pulse pressure

Although brachial‐ankle pulse wave velocity (baPWV) has been widely used as an index of arterial stiffness, no consensus exists about whether baPWV can reflect central aortic stiffness. The authors investigated the association between baPWV and invasively measured aortic pulse pressure (APP) in a total of 109 consecutive patients (mean age, 62.3 ± 11.3 years; 67.9% men). Most patients (91%) had obstructive coronary artery disease, and mean baPWV and APP values were 1535 ± 303 cm/s and 66.8 ± 22.5 mm Hg, respectively. In univariate analysis, there was a significant linear correlation between baPWV and APP (r = .635, P < .001). The correlation between baPWV and APP remained significant even after controlling for potential confounders (β = 0.574, P < .001; R² = .469). Arterial stiffness measured by baPWV showed a strong positive correlation with invasively measured APP, independent of clinical confounders. Therefore, baPWV can be a good marker of central aortic stiffness.     

Mechanism of pulmonary venous pressure and flow waves

Summary The pulmonary venous systolic flow wave has been attributed both to left heart phenomena, such as left atrial relaxation and descent of the mitral annulus, and to propagation of the pulmonary artery pressure pulse through the pulmonary bed from the right ventricle. In this study we hypothesized that all waves in the pulmonary veins originate in the left heart, and that the gross wave features observed in measurements can be explained simply by wave propagation and reflection. A mathematical model of the pulmonary vein was developed; the pulmonary vein was modeled as a lossless transmission line and the pulmonary bed by a three-element lumped parameter model accounting for viscous losses, compliance, and inertia. We assumed that all pulsations originate in the left atrium (LA), the pressure in the pulmonary bed being constant. The model was validated using pulmonary vein pressure and flow recorded 1 cm proximal to the junction of the vein with the left atrium during aortocoronary bypass surgery. For a pressure drop of 6 mmHg across the pulmonary bed, we found a transit time from the left atrium to the pulmonary bed ofτ ≈ 150ms, a compliance of the pulmonary bed ofC ≈ 0.4ml/mmHg, and an inertance of the pulmonary bed of 1.1mmHgs²/ml. The pulse wave velocity of the pulmonary vein was estimated to bec ≈ 1 m/s. Waves, however, travel both towards the left atrium and towards the pulmonary bed. Waves traveling towards the left atrium are attributed to the reflections caused by the mismatch of impedance of line (pulmonary vein) and load (pulmonary bed). Wave intensity analysis was used to identify a period in systole of net wave propagation towards the left atrium for both measurements and model. The linear separation technique was used to split the pressure into one component traveling from the left atrium to the pulmonary bed and a reflected component propagating from the pulmonary bed to the left atrium. The peak of the reflected pressure wave corresponded well with the positive peak in wave intensity in systole. We conclude that the gross features of the pressure and flow waves in the pulmonary vein can be explained in the following manner: the waves originate in the LA and travel towards the pulmonary bed, where reflections give rise to waves traveling back to the LA. Although the gross features of the measured pressure were captured well by the model predicted pressure, there was still some discrepancy between the two. Thus, other factors initiating or influencing waves traveling towards the LA cannot be excluded.     

脉压及脉压指数与冠状动脉病变严重程度的相关性研究

目的:探讨脉压、脉压指数与冠心病严重程度的相关性,并比较脉压与脉压指数用以评价冠脉病变严重程度的相对优越性。方法:经冠脉造影（CAG）确诊的冠心病患者154例,其中ACS患者104例,包括急性心肌梗死（AMI）44例,不稳定型心绞痛（UAP）60例;稳定型心绞痛（SAP）50例;另设冠脉造影排除冠心病患者43例作为正常对照组。冠心病病变的严重程度分别用冠状动脉病变的血管支数、冠状动脉病变评分和冠状动脉狭窄程度表示。结果:脉压及脉压指数与冠心病患者冠脉病变的严重程度密切相关,而与血脂、血糖、体重指数等无明显关系。结论:脉压及脉压指数是较为方便的反映大动脉弹性的参数,与冠状动脉病变的严重程度密切相关,可作为全身心血管病的一个危险信号,指导早期干预,且脉压指数在一定程度上较之脉压有更大的优势。