Tp-Te间期、Tp-Te/QT比值预测冠状动脉慢血流现象的临床价值

目的:探讨T波峰末间期(Tp-Te间期)、Tp-Te间期与QT间期的比值(Tp-Te/QT比值)与冠状动脉慢血流(CSF)的关系及预测价值.方法:选取2017年1月至2019年10月于郴州市第一人民医院就诊并行冠状动脉造影的患者230例,分为CSF组(n=118)和对照组(n=112),记录患者基础数据;通过心肌梗死溶...     

急性病毒性心肌炎患者复极跨壁离散度与前脑钠肽的相关性

目的探索急性心肌炎患者复极跨壁离散度的特点,分析T波峰末(Tp-Te)间期与前脑钠肽的相关性。方法纳入80例病毒性心肌炎患者作为实验组,收集性别、年龄、肌钙蛋白(c Tn I)、肌酸激酶同工酶(CK-MB)、前脑钠肽(BNP)等数据,测量心电图的心率、QT间期、Tp-Te间期。另外收集与实验组性别、年龄几乎匹配的78例诊断为室上性心动过速(入院时未发作)患者作为对照组,收集对照组上述数据。结果两组QT间期比较无统计学差异(P>0.05);实验组Tp-Te间期延长(P<0.05),BNP较对照组高(P<0.05)。另外,对急性心肌炎患者进行心律失常亚组分析,心律失常组与未发生心律失常组相比,Tp-Te间期无统计学差异(P>0.05),BNP水平差异显著(P<0.05);Tp-Te间期与BNP无相关性(r=0.201,P=0.254)。结论急性病毒性心肌炎患者Tp-Te间期延长,BNP水平升高,发生心律失常的患者BNP水平更高,但两者无相关性。     

心肌梗死患者QTd、Tp-Te和Tp-Te/QT的观察

目的观察心肌梗死后3~6个月患者心电图QTd、Tp-Te和Tp-Te/QT与对照组之间有无差异。方法选取自2011年1月至9月行心电图检查的心梗后3~6个月患者30例,男14例,女16例,平均年龄(51.2±11.94)岁;收集年龄、性别相匹配的对照组30例,男15例,女15例,平均年龄(50.4±9.45)岁,测量各组心电图QTd、Tp-Te间期并计算Tp-Te/QT值。结果心梗组Tp-Te和Tp-Te/QT比值均大于对照组,差异具有统计学意义(心梗组Tp-Te:101.9±14.5ms;Tp-Te/QT:0.287±0.04;对照组Tp-Te:75.7±12.4ms;Tp-Te/QT:0.193±0.03;p<0.05);QTd在两组之间无差异(心梗组:40.5±3.9ms;对照组:37.9±3.8ms;p>0.05)。结论心梗患者Tp-Te,Tp-Te/QT比值增高,可反映跨室壁复极离散度的变化,与心律失常的发生关系密切。     

心电图Tp-Te间期、Tp-Te/QT比值与恶性室性心律失常的关系

目的探讨心电图T波峰末间期(Tp-Te)、Tp-Te/QT比值对恶性室性心律失常(MVA)的诊断价值。方法连续入选2017年1月1日至2018年1月1日于保定市第一中心医院西院心电图、脑电图二室行24 h 12导联动态心电图检查的患者412例为研究对象。根据是否发生恶性室性心律失常分为两组:恶性室性心律失常组72例;无恶性室性心律失常组340例。分别测定两组患者Tp-Te间期、QT间期,计算出Tp-Te间期、QTc间期及Tp-Te/QT比值,并对两组患者Tp-Te间期、QTc间期及Tp-Te/QT比值进行统计学分析。结果恶性室性心律失常组的Tp-Te间期、Tp-Te/QT比值均较非恶性室性心律失常组明显增加(P0.001)。结论 Tp-Te间期、Tp-Te/QT比值增加对于恶性室性心律失常的发生均有预测价值。     

Tp-Te间期的细胞电生理基础和临床价值

T波峰末间期(Tp-Te间期)是指心电图T波顶点至T波终末的时间间期。Tp-Te间期与中层心肌细胞独特的电生理特性有关。Tp相当于心外膜复极结束,Te相当于中层心肌细胞复极结束。最新研究显示,Tp-Te间期反映了跨室壁复极离散度,该指标在一些疾病如Brugada综合征、长QT综合征、短QT综合征等发生恶性心律失常的预测评估中有临床价值。     

院前急救心力衰竭患者血浆BNP与心电图QRS波时限及Tp-Te间期的相关性

目的研究院前急救心力衰竭患者血浆脑钠肽(BNP)与心电图磁QRS波时限及T波峰-末(Tp-Te)间期的相关性。方法 120例院前心力衰竭急救患者按心功能分级分为观察A组(n=40)、观察B组(n=30)和对照组(n=50),对照组采取常规心力衰竭处理措施,观察组进行心电图QRS波时限、Tp-Te间期和血浆脑钠肽(BNP)检测,在对照组的基础上实施预见性治疗抢救措施,对比血浆BNP、心电图QRS波时限及Tp-Te间期指标及3组院前生存率、住院生存率和出院后6个月复住率。结果观察A组的血浆BNP水平、心电图QRS波时限和Tp-Te间期均显著低于观察B组(P0.05);观察A组的院前生存率和住院生存率均显著高于其他两组,6个月复住率显著低于其他两组(P0.05),观察B组的院前生存率和住院生存率均显著高于对照组,6个月复住率显著低于对照组(P0.05)。结论血浆BNP水平作为心力衰竭的分层和预后的重要指标,随着心功能分级的增加而显著上升,心电图QRS波时限及Tp-Te间期随着血浆BNP的增加逐渐延长,血浆BNP、心电图QRS波时限及Tp-Te间期的变化能够为恶性心律失常等不良事件的预测提供科学依据。     

AMI病人心电图Tp-Te、Tp-Te/QT与室性心律失常及心功能的关系

目的 分析急性心肌梗死(AMI)病人心电图Tp-Te、Tp-Te/QT与室性心律失常发生及心功能的关系。方法 选取2017年12月—2020年8月徐州市丰县人民医院收治的89例AMI病人作为研究对象,并依照病人是否出现室性心律失常分为室性心律失常组(51例)和无室性心律失常组(38例)。入组后测定其心功能,采用日本福田十二导联同步心电图机对病人心电图进行检查,入院后行24 h十二导联同步动态心电图检查;采用Pearson相关性分析心电图Tp-Te、Tp-Te/QT与心功能指标的相关性,采用线性回归模型分析Tp-Te、Tp-Te/QT与AMI并发室性心律失常的关系。结果 室性心律失常组急性期Tp-Te、Tp-Te/QT水平明显高于无室性心律失常组,差异有统计学意义(P<0.05),两组恢复期Tp-Te、Tp-Te/QT水平比较差异无统计学意义(P>0.05);室性心律失常组每搏量、左室射血分数水平明显低于无室性心律失常组,血清肌钙蛋白I(cTnI)和N末端脑钠肽前体(NT-proBNP)水平明显高于无室性心律失常组,差异均有统计学意义(P<0.05)。高Tp-Te和高T...     

Tp-Te间期和Tp-Ted在急性心肌梗死患者发生室性心律失常中的临床价值

目的探讨T波峰-末间期(Tp-Te间期)和Tp-Te间期离散度(Tp-Ted)在急性心肌梗死患者发生室性心律失常中的意义。方法收集该院2011年8月至2013年7月已收治的140例确诊急性ST段抬高型心肌梗死心内科住院患者,按照心律失常类型分为三组,室性心动过速组42例,室性早搏组72例,无室性心律失常组26例,分析比较各组Tp-Te间期及Tp-Ted情况。结果三组之间性别、年龄、BMI、Killip分级、吸烟、饮酒、高血压情况差异无统计学意义(P>0.05)。急性期FPG、Tp-Te、Tp-Ted高于恢复期(P<0.05);急性期与恢复期之间TG、CHOL、LDL-C、K+、Na+水平差异无统计学意义(P>0.05)。结论 Tp-Te间期和Tp-Ted可用于区分急性心肌梗死患者室性心律失常类型。     

术前心电图表现预测慢性心衰患者心脏再同步化治疗效果的临床价值

目的 探讨术前心电图表现对慢性心衰（Chronic heart failure,CHF）患者心脏再同步化治疗（Cardiac resynchronization therapy,CRT）疗效的预测价值。方法 纳入我院2015年10月～2017年10月收治的慢性心衰患者80例,所有患者均接受CRT治疗,根据治疗效果分成有效组、无效组。其中有效指术后6个月患者心功能（NYHA分级）改善≥1级,或超声心动图提示左室收缩末容积（end-systolic volume,ESV）下降>15%,或左室射血分数（Left ventricular ejection fraction,LVEF）绝对值上升>5%,未达上述标准及死亡均视为无效。所有纳入者均在术前接受心电图检查,比较两组临床特征,包括性别、年龄、病程、体质指数、基础病因、心功能分级、房颤、高血压、冠脉问题、糖尿病、术前心电图指标（心率、Tp-Te间期、QRS波时限）。通过绘制ROC曲线模型分析术前心电图指标对CRT治疗无效的预测价值,采用Logistic回归性分析明确CRT治疗无效的独立危险因素。结果 在术后6个月,有23例CHF患者CRT治疗无效,占28.75%,57例有效,占71.25%。无效组病程≥3年、NYHAⅣ级、有房颤、有冠脉问题占比分别为78.26%、47.83%、52.17%、47.83%,较有效组的49.12%、10.53%、12.28%、10.53%更高,且无效组心率、Tp-Te间期、QRS波时限均高于有效组,差异有统计学意义（P<0.05）。经ROC曲线模型提示心率、Tp-Te间期、QRS波时限预测CHF患者CRT治疗无效的曲线下面积分别为0.710、0.764、0.742。经Logistic回归性分析提示病程、NYHA分级、房颤、冠脉问题以及心率、Tp-Te间期、QRS波时限是CHF患者CRT治疗无效的独立危险因素（P<0.05）。结论 术前心电图检查能明确CHF患者心率、Tp-Te间期以及QRS波时限,三者对CRT治疗效果具有一定预测价值,且均为CRT无效的危险因素。     

高血压左心室肥大患者T波峰-末间期的检测

目的:检测高血压左心室肥大患者的T波峰一末间期(Tp-Te间期)TL心率校正的Tp-Te/√R-R间期,并探讨其可能的临床意义.方法:依据超声心动图测定的左室重量指数(LVMI)分为正常组和左室肥大组.比较正常组与高血压左室肥大组Tp-Te间期及Tp-Te/√R-R间期的差异.结果:正常组男性Tp-Te间期及Tp-Te/√R-R间期长于女性(P＜0.05);左室肥大组男、女性Tp-Te间期及Tp-Te/√R-R间期均比正常组明显延长(P＜0.05,P＜0.01).结论:高血压左心室肥大患者的Tp-Te间期及Tp-Te/√R-R间期比正常人明显延长,可能成为预测此类患者发生心律失常事件的临床指标之一.     

阿立哌唑对心电图Tp-Te间期的影响

目的观察抗精神病药阿立派唑对精神分裂症患者Tp-Te间期的影响。方法收集35例应用抗精神病药阿立派唑和26例应用氯氮平治疗的首发精神分裂症患者,氯氮平组给予氯氮平200~400mg口服,阿立哌唑组给予阿立哌唑20~30mg口服,治疗前及治疗4周后分别记录同步12导联心电图,对Tp-Te间期进行手工测量,计算校正的TP-TE间期(Tp-Te/√RR),并进行组间比较。结果治疗4周后,氯氮平组的Tp-Te间期及Tp-Tec间期与治疗前相比较明显延长,且与阿立哌唑组相比较具有统计学意义(p<0.05)。结论与氯氮平相比,阿立哌唑对心电图Tp-Te间期及Tp-Tec间期的影响较小,安全性相对较大。     

The meaning of the Tp-Te interval and its diagnostic value

Background

The interval between T peak (Tp) and T end (Te) has been proposed as a measure of transmural dispersion of repolarization, but experimental and clinical studies to validate Tp-Te have given conflicting results. We have investigated the meaning of Tp-Te and its diagnostic potential.

Methods

We used a digital model of the left ventricular wall to simulate the effect of varying action potential durations on the timing of Tp and Te. Furthermore, we used the vectorcardiogram to explain the relationships between Tp locations in the precordial electrocardiogram leads.

Results

Prolongation or ischemic shortening of action potentials in our model did not result in substantial Tp shifts. The phase relationships revealed by the vectorcardiogram showed that Tp-Te in the precordial leads is a derivative of T loop morphology.

Conclusion

Tp-Te is the resultant of the global distribution of the repolarization process and is a surrogate diagnostic parameter.     

International Hemoglobin Information Center Policies - Ihic

Abstract

The levels of the inactive hemoglobin (Hb) pigments [such as methemoglobin (metHb), carboxyhemoglobin (HbCO) and sulfohemoglobin (SHb)] and the active Hb [in the oxyhemoglobin (oxyHb) form] as well as the blood Hb concentration in healthy non pregnant female volunteers were determined using a newly developed multi-component spectrophotometric method. The results of this method revealed values of SHb% in the range (0.0727–0.370%), metHb% (0.43–1.0%), HbCO% (0.4–1.52%) and oxyHb% (97.06–98.62%). Furthermore, the results of this method revealed values of blood Hb concentration in the range (12.608–15.777?g/dL). The method is highly sensitive, accurate and reproducible.     

慢型、潜在型克山病患者的血管内皮功能观察

目的观察山东省慢型、潜在型克山病患者的临床特点和血管内皮功能,探讨机体内皮功能失调与克山病发生发展的关系。方法选择慢型、潜在型克山病患者57人、病区健康人34人,分别采集清晨空腹血检测ET、NO、NOS、iNOS及cNOS含量及活性。结果(1)克山病患者ET水平明显高于病区健康人(P<0.01);心功能越差,ET升高越明显(P<0.01);(2)NO和NOS含量,潜在型、慢型克山病均明显高于病区健康人(P<0.01);慢型高于潜在型(P<0.01);iN-OS含量克山病患者也高于病区健康人(P<0.05);慢型克山病高于潜在型克山病(P<0.05)。结论ET、NO水平的变化可能作为一种中间环节参与了克山病的发病机制;心功能不同,血浆ET、NO升高的程度也不同;ET、NO可作为克山病病情严重程度的预测指标。     

The Mitochondrial Permeability Transition: Role in Ischemia/Reperfusion Injury

The mitochondrial permeability transition (MPT) occurs when a non-specific pore opens in the inner mitochondrial membrane and converts the mitochondrion from an organelle whose ATP production sustains the normal function of the cell to an instrument of death. Conditions favouring the MPT including high [Ca2+], oxidative stress and adenine nucleotide depletion, all of which occur when a tissue is reperfused following a period of ischemia. Cyclosporin A (CsA) and low pH (<7.0) are potent inhibitors of the MPT. Methods have been devised to demonstrate directly that the MPT pores open upon reperfusion but not during ischemia. The mechanism of the MPT appears to involve binding of mitochondrial cyclophilin (CyP) to the adenine nucleotide translocase (ANT) followed by a calcium-mediated conformational change that converts the ANT into a non-specific pore. Understanding the molecular mechanism has assisted in devising strategies that can be used to protect tissues from damage caused by reperfusion injury. These might also be of benefit in the prevention of multiple organ failure for which reperfusion injury of the gut is thought to be the initial trigger. Protective regimes include the pretreatment of tissues prior to ischemia/reperfusion with CsA (binds to CyP), free radical scavengers that reduce oxidative stress (e.g., pyruvate and propofol) and agents that decrease pHi (e.g., pyruvate or amelioride derivatives). Reperfusion injury can produce both immediate cell death by necrosis or delayed apoptotic cell death and it appears that the mitochondria determine which route is taken. Prolonged opening leads to rapid cell death by necrosis, whilst transient opening leads to cytochrome c release and subsequent apoptosis hours or days later.     

Usefulness of procalcitonin for diagnosis of infective endocarditis

The aim of this study was to evaluate the accuracy of procalcitonin (PCT) in predicting infective endocarditis (IE). 23 adult patients with IE, 30 patients with sepsis and 30 with tick-borne encephalitis were included in this prospective study. The PCT serum level, C-reactive protein (CRP), total leukocyte, and immature polymorphonuclear (PMN) cell counts were determined on admission, prior to the institution of antibiotic therapy, and compared according to the diagnosis. The median PCT level in patients with IE endocarditis was 0.81 ng/ml, in patients with sepsis it was 43.74 ng/ml, and in the group with viral infection it was 0.25 ng/ml (P < 0.001). The highest PCT level was found in patients with Staphylococcus aureus endocarditis. The area under the receiver operating characteristic curve that used PCT to predict IE was 0.722 (95% CI 0.572–0.873), compared with 0.909 (95% CI 0.829–0.989) for CRP, 0.699 (95% CI 0.551–0.846) for immature PMN cell count, and 0.619 (95% CI 0.468–0.770) for leukocyte count. Our study fails to demonstrate superiority of PCT as a diagnostic laboratorial parameter in predicting IE compared to CRP.     

Linear affine transformations between 3-lead (Frank XYZ leads) vectorcardiogram and 12-lead electrocardiogram signals

Background

Recent advances in computer graphics and wireless technologies have renewed interest in vectorcardiogram (VCG) signals that use fewer leads than the conventional 12-lead electrocardiogram (ECG) signals for medical diagnostic applications. However, most cardiologists are accustomed to the 12-lead ECG even though some of the leads are either nearly aligned with or derived from the others and consequently contain redundant information. The ability to transform from orthogonal 3-lead VCG to 12-lead ECG enables the use of fewer leads for signal analysis, computer visualization, and wireless transmission of signals. This can also improve mobility, albeit limited, to the patients.

Materials and Methods

We present a statistical approach to transform 3-lead Frank VCG to 12-lead ECG signals and vice versa, based on Dower's pioneering work on lead tranformation. This approach enables compensation of baseline shifts and other constant biases present in long ECG data streams, so that the resulting statistical transforms can be more consistent and accurate. We compare the performance of the affine transform with that of Dower transform (from 3 to 12 and from 12 to 3) using the data from the PhysioNet PTB database.

Results

The results show that for both myocardial infarction (MI) and healthy control (HC) subjects, the statistical affine transform presented here maps 3-lead VCG to12-lead ECG more accurately than Dower or other lead transformation matrices of the ECG recordings.

Discussion

This investigation also shows the limitations associated with single dipole assumption that underlies Dower's geometric transformation. The results also indicate that lead transformation accuracy can be improved using separate customized transforms to, for example, age or pathologic conditions (here, MI vs HC) than a single statistical or geometric transform. Pertinently, we find that the affine transform coefficients can serve as discriminating features for classification/discrimination of MI patients from HC subjects.     

Expression of membrane-type matrix metalloproteinases in synovial tissue from patients with rheumatoid arthritis or osteoarthritis

We investigated the expression of membrane-type matrix metalloproteinase (MT-MMP) and matrix metalloproteinase (MMP) mRNAs in synovial tissue from patients with rheumatoid arthritis (RA, n = 5) or osteoarthritis (OA, n = 5) by Northern blot analysis. Northern analysis demonstrated strong expression of MT1-MMP, MT3-MMP, MMP-1, and MMP-3 and weak expression of MT2-MMP and MMP-8 in synovial tissue from patients with RA or OA. MT4-MMP was not detected. No significant difference was shown in the expression of MT-MMP mRNAs between RA and OA. Synovial tissue of RA or OA patients expressed MT-MMPs as well as MMPs. These results indicate that, in addition to MMPs, MT1-MMP, MT3-MMP, and probably MT2-MMP may play a role in the degradation of bone and cartilage matrix in RA and OA. Such information may provide a clue to the development of a novel therapeutic approach targeted on the prevention of joint destruction. Received: April 30, 2000 / Accepted: September 19, 2000