CHA2DS2-VASc评分对急性心肌梗死患者行冠状动脉介入治疗无复流现象预测

目的 本研究旨在验证CHA2DS2 VASc评分对直接经皮冠状动脉介入治疗（PCI）的ST段抬高型心肌梗死（STEMI）患者无复流现象的临床预测价值。方法 将我院收治接受原发性PCI治疗的300例STEMI患者分为两组：将27例无复流患者作为第一组，将其余273例患者作为对照组。计算每例患者CHA2DS2 VASc风险评分。结果 CHA2DS2 VASc评分与无复流相关性的多变量分析差异有统计学意义（P<0.05）。CHA2DS2 VASc评分中各个成分对无复流预测能力差异有统计学意义（P<0.05）。结论 在接受PCI治疗的STEMI患者中，较高的CA2DS2 VASc评分与无复流现象风险和住院病死率相关。     

Augmented Vector Right ST-Segment Elevation: Pearls and Pitfalls

ST-segment elevation myocardial infarction (STEMI) is characterized by ST-segment elevation in at least 2 contiguous leads, chest discomfort, and the release of biomarkers requiring emergent revascularization. In 2013, the American College of Cardiology Foundation/American Heart Association revised STEMI guidelines to include augmented vector right (aVR) ST-segment elevation to be treated as a STEMI equivalent. However, aVR ST-segment elevation with multilead ST depression can occur in presentations other than occlusive myocardial infarctions. The purpose of this clinical feature is to provide a brief review of aVR ST-segment elevation, explore approaches to clinical decision making, and provide tools to support nurse practitioners caring for patients with cardiac issues.     

两种负荷心电图试验对冠心病的诊断价值研究

目的 评价运动心电图试验(EET)、双嘧达莫心电图负荷试验(DPET)及联合应用(联合试验AD对冠心病的诊断价值。方法 选择183例冠状动脉造影(CAG)检查的患者，并在同期内(间隔小于1周)接受。EET、DPET检查。将CAG结果分别与EET、DPET和AT结果进行对比分析。结果 这两种无伤检查和联合检查诊断冠心病的敏感性分别为67．2％、60．3％和55．2％，特异性分别为：70．4％、74．4％和92．8％，准确性分别为：69．4％、69．9％和85．3％。结论 EET和DPET联合应用对冠心病的诊断具有较高的特异性和准确性，且费用低、无创伤，适宜基层医院推广。     

Pyramid Electrode Location in a Cardiac Micropotential Study

There are several electrode systems dealing with low noise, body surface, and ECG recordings that have been suggested by various investigators. In the last few years, the most developed system for late potential detection has been related to the uncorrected Frank XYZ leads. However, for His bundle detection many different electrode networks have been used. A pyramid-type electrode system has been used previously for His-Purkinje signal measurement and, with some modifications, for late ventricular activity recordings. This pyramid-type system was used to evaluate 300 adult patients with coronary heart disease (CHD) or cardiomyopathy. In the proposed system, electrodes are located near the myocardium with their configuration consisting of three electrode pairs forming a pyramidal shape. Each electrode can also play the role of the top of the pyramid, with all measurement directions converging to a point. By changing the pyramidal top, signals can be detected in various chosen measurement directions. The pyramid system provides spatial averaging facility, allowing the whole measuring system (consisting of low noise multi-input amplifiers) to detect signals in the range of 1 microVp-p on a beat-to-beat basis. In the majority of cases in hospital environments, however, a number of digital averaging cycles is still necessary. Using this system, late potentials (LP) were found in 29% of the patients without myocardial infarction (MI) and in 86% of cases with remote MI and sustained ventricular tachycardia (VT) and/or ventricular fibrillation (VF). Waveforms suspected to be of His-Purkinje System (HPS) origin were detected in 71% of subjects with normal or prolonged P-R segment.     

心电图P波宽度在优化双腔起搏器房室间期中的价值

目的:探索以心电图P波宽度优化双腔起搏器房室间期(AV间期)的方法,以期获得良好的血流动力学效果。方法:选择63例因Ⅲ度或高度房室传导阻滞植入Medtronic双腔起搏器的患者,测量其心电图自身P波宽度,或从心房起搏脉冲至起搏P波末端的宽度,在此测量值上加100ms,设定为双腔起搏器的感知AV间期(SAV)和起搏AV间期(PAV)。每例患者分别在出厂常规设置的AV间期和根据心电图优化的AV间期设定值下进行超声心动图检查,比较即刻血流动力学参数。结果:经心电图优化AV间期后,患者左室舒张末容积(LVEDV)、左室收缩末期容积(LVESV)和左室射血分数(LVEF)均较常规出厂设置的AV间期有显著改善(69.5±11.2比72.3±12.7;29.5±9.5比27.88±10.07;63.6±5.3比67.2±6.2,P<0.05)。结论:根据心电图P波宽度优化双腔起搏器AV间期,可获得良好的血流动力学效果,左室充盈改善,LVEF上升;且该法简单易行,具广泛的临床实用价值。     

Comparison of Polar® RS800G3™ heart rate monitor with Polar® S810i™ and electrocardiogram to obtain the series of RR intervals and analysis of heart rate variability at rest

The Polar^® RS800G3^? rate monitor was released in the market to replace the Polar^® S810i^?, and few studies have assessed that the RR series obtained by this equipment is reliable for analysis of heart rate variability (HRV). We compared HRV indexes among the devices Polar^® RS800G3^?, Polar^® S810i^? and eletrocardiogram (ECG) to know whether the series of Polar^® RS800G3^? are as reliable as those devices already validated. We analysed data from 30 healthy young adults, male, with an average age of 20·66 ± 1·40 years, which had captured the heart rate beat to beat in the three devices simultaneously with spontaneously breathing, first in the supine position and subsequently sit both for 30 min. The obtained series of RR intervals was used to calculate the indexes of HRV in the time domain (SDNN and RMSSD) and in the frequency domain (LF, HF and LF/HF). There were no significant differences in HRV indexes calculated from series obtained by the three devices, regardless of the position analysed, and a high correlation coefficient was observed. The results suggest that the Polar^® RS800G3^? is able to capture series of RR intervals for analysis of HRV indexes as reliable as those obtained by ECG and Polar^® S810i^?.     

QT interval dispersion in the patients with central serous chorioretinopathy

AIM: To evaluate QT dispersion (QTD) in patients with central serous chorioretinopathy (CSC). METHODS: This clinical, comperative, case-control study included 30 patients with CSC at acute phase (Group 1) and 30 age- and sex-matched healthy subjects (Group 2, the control group). From all subjects, a 12-lead surface electrocardiography was obtained. The heart rate (HR), QT maximum (QTmax), QT minimum (QTmin), QT corrected (QTc), QTD and Tmean were manually measured and analyzed. Student’s t-test and Pearson’s method of correlation were used for statistical analysis. RESULTS: The patient and control groups were matched for age, smoking status (rate and duration) and gender. There were no significant differences with regard to these among the groups (P>0.05). The participants included 19 men (63.3%) and 11 women (36.7%) in Group 1, 20 men (66.7%) and 10 women (33.3%) in Group 2. QTmax, QTD and QTc were significantly higher than those of healthy controls (P<0.001 for QTmax, P=0.01 for QTD and P=0.001 for QTc). QTmin, Tmean and HR did not differ significantly between the study groups (P=0.28 for QTmin, P=0.56 for Tmean and P>0.05 for HR). No significant correlation was found between duration of the disorder and QTD values (r=0.13, P>0.05). CONCLUSION: These findings suggest that CSC may be associated with an increase in QTD and that the patients might be at risk for ventricular arrhythmia.     

Association between a prolonged corrected QT interval and outcomes in patients in a medical Intensive Care Unit

Introduction:

Patients admitted into a medical Intensive Care Unit (ICU) have varying illnesses and risk factors. An electrocardiogram (ECG) is a useful tool to assess the cardiac status. The aim of the study was to determine the prevalence of QT prolongation of the ECG in patients admitted to a medical ICU in a tertiary hospital, to assess outcomes in terms of mortality, cardiovascular events, and duration of ICU stay.

Materials and Methods:

Prospective observational study, 6 months duration, assessing the prevalence of prolonged corrected QT interval (QTc) at admission into a medical ICU. A QTc calculated by Bazett''s formula, of >440 ms for males and >460 ms for females was considered prolonged. Details of illness, clinical and lab parameters were monitored.

Results:

The total number of patients screened was 182. There was a high prevalence of prolonged QTc (30%) on admission to the ICU. This reduced to 19% on day 3 (P = 0.011). In patients with a prolonged QTc the odds ratio of adverse outcome from ICU was 3.17 (confidence interval [CI]: 1.52–6.63) (P = 0.001) and of adverse outcome for hospital stay was 2.27 (CI: 1.11–4.66) (P = 0.014). In the study, 35% of all patients received drugs with QT prolonging action. Of patients with a prolonged QTc at admission 18 (35%) received a QT prolonging drug.

Conclusions:

We found that prolonged QTc is common (30%) in our medical ICU at admission and a large proportion (35%) received drugs capable of prolonging QT interval. These patients with QTc prolongation have a higher odds ratio for adverse outcomes.