Optimal Delineation of Ambulatory Holter ECG Events via False-Alarm Bounded Segmentation of a Wavelet-Based Principal Components Analyzed Decision Statistic

The aim of this study is to develop and describe a new ambulatory holter electrocardiogram (ECG) events detection-delineation algorithm with the major focus on the bounded false-alarm probability (FAP) segmentation of an information-optimized decision statistic. After implementation of appropriate preprocessing methods to the discrete wavelet transform (DWT) of the original ECG data, a uniform length sliding window is applied to the obtained signal and in each slid, six feature vectors namely as summation of the nonlinearly amplified Hilbert transform, summation of absolute first order differentiation, summation of absolute second order differentiation, curve length, area and variance of the excerpted segment are calculated to construct a newly proposed principal components analyzed geometric index (PCAGI) by application of a linear orthonormal projection. In the next step, the α-level Neyman-Pearson classifier (which is a FAP controlled tester) is implemented to detect and delineate QRS complexes. The presented method was applied to MIT-BIH Arrhythmia Database, QT Database, and T-Wave Alternans Database and as a result, the average values of sensitivity and positive predictivity Se = 99.96% and P+ = 99.96% are obtained for the detection of QRS complexes, with the average maximum delineation error of 5.7, 3.8 and 6.1 m for P-wave, QRS complex and T-wave, respectively. Also, the proposed method was applied to DAY general hospital high resolution holter data (more than 1,500,000 beats including Bundle Branch Blocks-BBB, Premature Ventricular Complex-PVC and Premature Atrial Complex-PAC) and average values of Se = 99.98% and P+ = 99.97% are obtained for QRS detection. In summary, marginal performance improvement of ECG events detection-delineation process in a widespread values of signal to noise ratio (SNR), reliable robustness against strong noise, artifacts and probable severe arrhythmia(s) of high resolution holter data and the processing speed 155,000 samples/s can be mentioned as important merits and capabilities of the proposed algorithm.     

Determination of Impact Damage in CFRP via PVDF Signal Analysis with Support Vector Machine

Carbon fiber reinforced plastics (CFRPs) have high specific stiffness and strength, but they are vulnerable to transverse loading, especially low-velocity impact loadings. The impact damage may cause serious strength reduction in CFRP structure, but the damage in a CFRP is mainly internal and microscopic, that it is barely visible. Therefore, this study proposes a method of determining impact damage in CFRP via poly(vinylidene fluoride) (PVDF) sensor, which is convenient and has high mechanical and electrical performance. In total, 114 drop impact tests were performed to investigate on impact responses and PVDF signals due to impacts. The test results were analyzed to determine the damage of specimens and signal features, which are relevant to failure mechanisms were extracted from PVDF signals by means of discrete wavelet transform (DWT). Support vector machine (SVM) was used for optimal classification of damage state, and the model using radial basis function (RBF) kernel showed the best performance. The model was validated through a 4-fold cross-validation, and the accuracy was reported to be 92.30%. In conclusion, impact damage in CFRP structures can be effectively determined using the spectral analysis and the machine learning-based classification on PVDF signals.     

Ambulatory Monitoring of Heart Sounds via an Implanted Device Is Superior to Auscultation for Prediction of Heart Failure Events

BackgroundWe compared the relationship between the third heart sound (S3) measured by an implantable cardiac device (devS3) and auscultation (ausS3) and evaluated their prognostic powers for predicting heart failure events (HFEs).Methods and ResultsIn the MultiSENSE study, devS3 was measured daily with continuous values, whereas ausS3 was assessed at study visits with discrete grades. They were compared among patients with and without HFEs at baseline and against each other directly. Cox proportional hazard models were developed between follow-up visits and over the whole study. Simulations were performed on devS3 to match the limitations of auscultation. We studied 900 patients, of whom 106 patients experienced 192 HFEs. Two S3 sensing modalities correlated with each other, but at baseline, only devS3 differentiated patients with or without HFEs (P < 0.0001). The prognostic power of devS3 was superior to that of ausS3 both between follow-up visits (HR = 5.7, P < 0.0001, and 1.7, P = 0.047, respectively) and over the whole study (HR = 2.9, P < 0.0001, and 1.4, P = 0.216, respectively). Simulation results suggested this superiority may be attributed to continuous monitoring and to subaudible measuring capability.ConclusionsS3 measured by implantable cardiac devices has stronger prognostic power to predict episodes of future HFEs than that of auscultation.     

Delineation of an Octopus‐Like Thrombus Attached to the Eustachian Valve

Eustachian valve (EV) is a vestige of the valve of the inferior vena cava which directs the umbilical vein blood through open foramen ovale in fetal life. Following birth it gradually regresses, but it may persist in variable size, shape, and thickness as a functionless and benign structure. However, there are reports suggesting that persistent EV may not be completely innocent. It has been accused of being a predisposing cause of patent foramen ovale and paradoxical embolism and also interfering with transseptal interventional procedures. It may serve as a site of infective vegetations and be mistaken as a tumor or thrombus. In the present case, an octopus‐like thrombus attached to the EV was delineated with the utility of two‐dimensional and real time three‐dimensional transesophageal echocardiography. EV was considered to play an essential role in preventing potential pulmonary embolism.     

Inflammatory Bowel Disease Is Associated With an Increased Risk of Incident Acute Arterial Events: Analysis of the United Kingdom Biobank

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A Decision Analysis for Treatment of Clinically Localized Prostate Cancer

OBJECTIVE: To determine the preferred treatment of clinically localized prostate cancer. DESIGN: Cancer grade, patient age, and comorbidities are considered in a Markov model with Monte Carlo sensitivity analyses. Large and recent pooled analyses and patient-derived utilities are included. RESULTS: Principal findings suggest benefit for radical prostatectomy relative to watchful waiting for men under 70 years of age with low to moderate comorbidity. Men older than 70 with high comorbidity and disease of low to moderate grade do better with watchful waiting. CONCLUSIONS: Cohort-level sensitivity analyses suggest a quality-adjusted treatment benefit for radical prostatectomy for younger men and treatment harm for older men. Tailored patient and clinician decisions remain necessary, especially for men older than 70 in good health but with aggressive cancers.     

Cardiovascular Events in Patients with Increased Lipoprotein (a) – Retrospective Data Analysis in an Outpatient Department of Lipid Disorders

IntroductionThe role of lipoprotein (a) (Lp(a)) in atherogenesis has been previously demonstrated in several trials reporting various and sometimes contradictory findings. Our retrospective study analyzed the incidence of cardiovascular events in patients with Lp(a) plasma level of more than 250 mg/l, which has been defined as a threshold in previous publications.MethodsThe files of 303 patients with Lp(a) of more than 250 mg/l were divided into 5 groups categorized by Lp(a) level increase and reviewed regarding age, sex, BMI, dyslipidemias, arterial hypertension, diabetes mellitus, family history of cardiovascular events, fatty liver and incidence of vascular events in coronaries, carotids and lower extremities.ResultsNo significant differences were observed with respect to sex, age, BMI, dyslipidemias, diabetes mellitus, arterial hypertension and hepatic steatosis. The likely occurrence of at least one event was 2.77 times more in the fourth (Lp(a) 1235 ± 82 mg/l) and 6.2 times more in the fifth (Lp(a) 2068 ± 471 mg/l) than in the first group (Lp(a) 322 ± 48 mg/l). The 5 groups differed with respect to average “events per patient” (p < 0.001). The magnitude of increased Lp (a) exceeded that of other risk factors.ConclusionA substantially (more than 1100 mg/l) elevated Lp(a) plasma level seems to be an important predictor for the occurrence of cardiovascular events. It makes sense in clinical practice to consider patients exhibiting this elevation as having a high cardiovascular risk. In case of progression of atherosclerotic complications the patients should be assigned for lipid apheresis.     

The Effect of Computerized Physician Order Entry with Clinical Decision Support on the Rates of Adverse Drug Events: A Systematic Review

Context Computerized physician order entry (CPOE) with clinical decision support (CDS) has been promoted as an effective strategy to prevent the development of a drug injury defined as an adverse drug event (ADE). Objective To systematically review studies evaluating the effects of CPOE with CDS on the development of an ADE as an outcome measure. Data Sources PUBMED versions of MEDLINE (from inception through March 2007) were searched to identify relevant studies. Reference lists of included studies were also searched. Methods We searched for original investigations, randomized and nonrandomized clinical trials, and observational studies that evaluated the effect of CPOE with CDS on the rates of ADEs. The studies identified were assessed to determine the type of computer system used, drug categories being evaluated, types of ADEs measured, and clinical outcomes assessed. Results Of the 543 citations identified, 10 studies met our inclusion criteria. These studies were grouped into categories based on their setting: hospital or ambulatory; no studies related to the long-term care setting were identified. CPOE with CDS contributed to a statistically significant (P ≤ .05) decrease in ADEs in 5 (50.0%) of the 10 studies. Four studies (40.0%) reported a nonstatistically significant reduction in ADE rates, and 1 study (10.0%) demonstrated no change in ADE rates. Conclusions Few studies have measured the effect of CPOE with CDS on the rates of ADEs, and none were randomized controlled trials. Further research is needed to evaluate the efficacy of CPOE with CDS across the various clinical settings.     

Placement of an intracoronary stent via translumbar puncture

Translumbar puncture for access to the central arterial tree has been used for aortography and for selective coronary angiography in selected patients where conventional peripheral access is not possible. A single case report of coronary angioplasty through this access technique is available in the literature. We report a case of coronary stent placement using the translumbar approach to access the coronary arteries. Cathet. Cardiovasc. Intervent. 46:340–342, 1999. © 1999 Wiley-Liss, Inc.     

Discrete phase of calcium excess in the process of deterioration in an individual rat myocyte

While there have been many reports of the significant role of cytoplasmic free calcium ion in myocardial injury, these have been carried out in multicellular preparations. Since cell injury may occur inhomogeneously, it is necessary to observe the 'history' of an individual myocyte in order to investigate the detailed role of the calcium ion in the process of myocardial injury. We have observed the natural history of individual myocytes isolated from the left ventricle of rats with respect to changes in shape and cytoplasmic free calcium concentration ([Ca2+]i) measured with fura-2. We can discriminate four phases in the time course of cell deterioration. In the first phase (phase O), the myocyte is rod shaped, quiescent and responsive to electrical stimulation. The [Ca2+]i is stable. In the next phase (Phase 1), once initiated, the myocyte exhibits an asynchronous wavy contraction and gradually decreases in length. The [Ca2+]i gradually increases with some fluctuation. Phase 2 is characterized by rapid development of contracture with a marked increase in [Ca2+]i. In the period following establishment of contracture (Phase 3), changes in [Ca2+]i vary from cell to cell, possibly because of leakage of the dye caused by loss of cell membrane integrity. Our results indicate that, during naturally occurring cell deterioration, loss of [Ca2+]i control at the membrane of the sarcoplasmic reticulum precedes contracture and catastrophic increase in [Ca2+]i.     

对新疆洛浦县农业区1972年人间鼠疫流行的回顾剖析

在新疆洛浦县玉龙喀什乡(约N37°07′,E80°)平原农业区,1972年7月15日～9月12日发生一次人间鼠疫流行。共发病27人,女18人,男9人。年龄在1.5～92岁之间,20～60岁者占15名。腺型19人,肺型4人,败血型4人,共病死12人,治愈15人。从4名病人体内分离出鼠疫菌,7名病人间接血凝试验(IHA)阳性。当时对此次流行的传染源及传播途径未能查明。有人推测是从毗邻平原荒漠鼠间鼠疫传入的。有人认为是昆仑山地旱獭(Marmota hymalayana)鼠疫传入的。经过1973年的调查,在昆仑山地查出了旱獭鼠疫疫源地。1973～1988年期间,虽然对洛浦一带平原荒漠进行多次调查,但均未查到鼠疫阳性材料。根据1972年以来的流行病学资料综合分析认为:1972年玉龙喀什乡人间鼠疫流行,是首发病人在昆仑山地(约N36°11′,E79°42′)被染疫旱獭染疫后,返回农业区发病、同时感染了室内游离蚤(Pulex irritans),染疫的游离蚤再去感染接触者所引起的。亦即通过人→蚤→人的传播途径使疫情蔓延开来。由于当时采取了疫区处理措施,从而控制了疫情流行。     

Non-Isothermal Kinetic Analysis of the Crystallization of Metallic Glasses Using the Master Curve Method

The non-isothermal transformation rate curves of metallic glasses are analyzed with the Master Curve method grounded in the Kolmogorov-Johnson-Mehl-Avrami theory. The method is applied to the study of two different metallic glasses determining the activation energy of the transformation and the experimental kinetic function that is analyzed using Avrami kinetics. The analysis of the crystallization of Cu₄₇Ti₃₃Zr₁₁Ni₈Si₁ metallic glassy powders gives E_a = 3.8 eV, in good agreement with the calculation by other methods, and a transformation initiated by an accelerating nucleation and diffusion-controlled growth. The other studied alloy is a Nanoperm-type Fe₇₇Nb₇B₁₅Cu₁ metallic glass with a primary crystallization of bcc-Fe. An activation energy of E_a = 5.7 eV is obtained from the Master Curve analysis. It is shown that the use of Avrami kinetics is not able to explain the crystallization mechanisms in this alloy giving an Avrami exponent of n = 1.     

地方性甲状腺肿流行区智力低下儿童头发中14种元素分析

本文用ICP-AES法测定了地甲肿流行区63名儿童(其中智力低下患儿41名)头发中Zn、Pb、Fe、Cu、Mn、Ca、Mg、Al、Sr、Ni、Cr、Sn、Se、I等14种常、微量元素的含量。结果表明智力低下儿童头发中Zn、Pb、Ca、Ni、Cr明显低于非病区对照组,而Fe、Mn、Al则明显高于非病区对照组。提示地甲肿流行区智力低下的发生,碘缺乏不是唯一的病因,而是多种元素作用的结果。     

Food as Medicine for Secondary Prevention of Cardiovascular Events Following an Acute Coronary Syndrome

Cardiovascular disease is the leading cause of death in men and women in the USA. Once a patient experiences an acute coronary syndrome (ACS), they are at increased risk for hospital readmission within 30 days and 6 months after discharge and more importantly, they have worse survival. Hospital readmissions lead to poor clinical outcomes for the patient and also significantly increase healthcare costs due to repeat diagnostic evaluation, imaging, and coronary interventions. The goal after hospital discharge is to modify cardiovascular (CV) risk factors including hypertension, hyperlipidemia, and diabetes to prevent repeat coronary events; however, drug therapy is only one aspect. Several diets have been shown to decrease weight and reduce these risk factors over short durations; however, most people typically cannot sustain their diet and regain the weight. The Intelligent Quisine (IQ) diet is a prepared meal plan that was designed to meet the American Heart Association and American Diabetes Association nutritional guidelines and simplify the daily consumption of a nutritionally complete, calorie conscious meal. The IQ diet has been shown to significantly reduce blood pressure, cholesterol levels, glucose levels, and weight over a 10-week period. Additional studies have shown that patients are able to remain compliant on the diet for a year and maintain the reduction of their CV risk factors. If patients are consistent with a healthy calorie conscious and nutritionally complete diet modifying CV risk factors long term, then food could be as powerful in reducing CV events as evidence-based drug therapy. There is a need to begin conceptualizing food as medicine. To this end, it is time for a randomized control trial implementing the IQ diet versus current standard dietary recommendations in a large number of patients and measuring hard CV endpoints. Many readmissions can be avoided with proper patient education and support emphasizing lifestyle modifications such as eating healthy and smoking cessation on a foundation of optimal medical therapy.     

The Risk of Cardiovascular Events in Primary Care Patients Following an Episode of Severe Hypertension

This retrospective study of office and hospital electronic medical records from June 1991 to June 2007 examines the occurrence of severe blood pressure (BP) elevation (>180/110 mm Hg) and the subsequent risk of cardiovascular events in a diverse set of primary care practices. A total of 18,747 patients were categorized according to BP using 3 methodologies based on the highest historical value, the first recorded value, and time-averaged antecedent values. During the follow-up period (median 3.8 years) there were 949 cardiovascular events and 80 cardiovascular-related deaths. Severe BP elevation occurred in 1566 (8.4%) patients. The age-adjusted incidence of cardiovascular events per 1000 patient-years was 5.9 in the normal BP group, 10.1 in the mild group, 15.1 in the moderate group, and 25.0 in the severe group. An episode of severe BP elevation is common in primary care practice and is associated with substantial excess cardiovascular morbidity.