先天性心脏病儿童与正常儿童圆顶尖角型T波的比较

摘要： 目的 比较先天性心脏病患儿与超声心动图正常儿童的圆顶尖角型T波在形态及高度上的区别。方法 回顾性分析本院2015年12月—2016年12月间心电图检查出圆顶尖角T波的儿童心电图114例, 根据超声心动图结果分成先天性心脏病组 （先心病组） 71例和超声心动图正常组 （正常组） 43例, 通过测量2组圆顶尖角型T波的高度比较2组圆顶尖角型T波在形态上的区别; 先心病组患者根据先天性心脏病种类不同分组, 比较各组间圆顶尖角型T波的高度。结果 与正常组相比, 先心病组的圆顶尖角型T波的第二峰大于第一峰的比例更高 （52.11% vs. 18.60%）, 且第二峰尖角波高度更高。不同先天性心脏病病种之间圆顶尖角型T波在高度及形态上差异无统计学意义 （P＞ 0.05）。结论 圆顶尖角型T波可出现在先天性心脏病患儿心电图中, 亦可出现在超声心动图正常儿童心电图中, 但先天性心脏病患儿有着更高的尖角T波, 且第二峰高于第一峰。     

心电图对急性心肌梗死相关血管的预计价值

对385例急性心肌梗死患者作选择性冠状动脉造影。心电图定位为前壁心梗的相关血管89%是左前降支动脉(LAD),下壁心梗的相关血管76.4%是右冠状动脉(RCA)。阻塞发生于 LAD、RCA及左迥旋支动脉(LCX)近端的分别占67%、58%与78%。近端病变90%以上为重度或完全阻塞。在下壁心梗早期心电图出现心前导联 ST 段下移,是病变广泛的一项指标。     

Three-Dimensional Electrocardiography of Cardiac Pacing

Electrocardiographic evaluation of modern pacing systems requires sustained documentation during iterative programming procedures, exercise testing or Holter monitoring. Documentation of a prolonged period of time in standard electrocardiography is based on horizontal compression. The value and limitations of a vertical compression with no change in horizontal chronology and waveform morphology are evaluated. The signal taken from a selected surface lead is introduced into an oscilloscope triggered by an electrocardiographic event along the horizontal axis. A continuous vertical monitoring provides a vertical superimposition of the consecutive cycles. The brightness is proportional to the amplitude of the signal and introduces a third dimension. The three-dimensional technique results in an original image allowing report miniaturization at standard 25 or 50 mm/sec paper speed. Appropriate lead selection and use of the brightness as a marker event allow reliable atrial activity identification. In rate responsive pacing evaluation, the procedure is specifically convenient to full disclosure of the chronotropic response. The main limitation is a high sensitivity to noise during recording. Further developments are to be expected based on computer-assisted electrocardiography.     

Estimation of noise level and signal to noise ratio of laplacian electrocardiogram during ventricular depolarization and repolarization

Body surface Laplacian ECG (LECG) has demonstrated its enhanced capability to localize cardiac electrical sources closest to the recording site. The aim of the present study was to evaluate the noise level and signal to noise ratio (SNR) in the LECG as compared to the potential ECG (PECG). Such evaluation is important to determine the applicability of the LECG to localizing and imaging of cardiac electrical activity in an experimental setting. Experimental studies were conducted in six healthy men. A 150-channel PECG was recorded from the anterolateral chest and the LECG was estimated using the finite difference algorithm. The noise level in the PECG and LECG was evaluated using multiple estimation protocols. The signal level during ventricular depolarization and repolarization was also estimated, and the corresponding SNR was calculated. Different filtering techniques were examined to evaluate their effects on the noise level and SNR of the LECG and PECG. The experimental results indicate that with basic signal processing techniques (baseline adjustment, three-point moving average filter, and Wiener spatial filter), the SNR of the LECG is about 30-40% of that of the PECG. Furthermore, the SNR estimated during ventricular depolarization is about three times that obtained during ventricular repolarization for the PECG and LECG. The present study indicates that the LECG derived from the PECG using a local finite difference estimation procedure has satisfactory SNR during the periods of ventricular depolarization and repolarization, and suggests the feasibility of estimating the LECG from the recorded PECG in human subjects in an experimental setting.     

External Jugular Vein Catheterization Using 'Intra-Atrial Electrocardiogram'

Purpose

To investigate the reliability of intra-atrial electrocardiogram (ECG) use for external jugular vein (EJV) catheterization.

Materials and Methods

Patients undergoing open heart surgery in Suleyman Demirel University Hospital between February and June 2006 were included in the study. Using a sterile Seldinger technique, a triple lumen polyurethane central venous catheter was introduced (Certofix® Trio V 720, length 20 cm, 7 French) under intra-atrial ECG guidance. The presence of an increase in P-wave size was recorded. Just after the surgery, a portable chest X-ray was taken. The method was considered to be successful when a change in P-wave could be seen and the catheter was in the superior vena cava, as well as when there was no change in P-wave and the catheter was not in the superior vena cava.

Results

In six patients (12%), we were not able to advance the guidewire. In the remaining 44 patients, the catheter was inserted without problem. Eight of these 44 catheters were positioned in the innominate vein, with a malposition ratio of 18%. The success rate of external jugular vein cannulation with intra-atrial ECG was 95%. No complications occured related to the EJV cannulation.

Conclusion

Considering that it is easily accessed without complication, and the malposition is successfully detected by intra-atrial ECG, EJV is a suitable access for central venous cannulation when internal jugular vein (IJV) is not usable.     

Performance of Reperfusion Therapy and Hospital Mortality in ST-Elevation Myocardial Infarction Patients with Non-Chest Pain Complaints

Purpose

ST-elevation myocardial infarction (STEMI) patients may visit the emergency department (ED) complaining of sensations of pain other than the chest. We investigated our performance of reperfusion therapy for STEMI patients presenting with non-chest pains.

Materials and Methods

This was a retrospective observational cohort study. STEMI patients who underwent primary percutaneous coronary intervention (PCI) were divided into a chest pain group and a non-chest pain group. Clinical differences between the two groups and the influence of presenting with non-chest pains on door-to-electrocardiograms (ECG) time, door-to-balloon time, and hospital mortality were evaluated.

Results

Of the 513 patients diagnosed with STEMI, 93 patients presented with non-chest pains. Patients in the non-chest pain group were older, more often female, and had a longer symptom onset to ED arrival time and higher Killip class than patients in the chest pain group. There was a statistically significant delay in door-to-ECG time (median, 2.0 min vs. 5.0 min; p<0.001) and door-to-balloon time (median, 57.5 min vs. 65.0 min; p<0.001) in patients without chest pain. In multivariate analysis, presenting with non-chest pains was an independent predictor for hospital mortality (odds ratio, 2.3; 95% confidence interval, 1.1-4.7). However, door-to-ECG time and door-to-balloon time were not factors related to hospital mortality.

Conclusion

STEMI patients presenting without chest pain showed higher baseline risk and hospital mortality than patients presenting with chest pain. ECG acquisition and primary PCI was delayed for patients presenting with non-chest pains, but not influencing hospital mortality. Efforts to reduce pre-hospital time delay for these patients are necessary.     

Association between electrocardiographic findings and cardiac dysfunction in adult isolated traumatic brain injury

Introduction:

Abnormal electrocardiographic (ECG) findings can be seen in traumatic brain injury (TBI) patients. ECG may be an inexpensive tool to identify patients at high risk for developing cardiac dysfunction after TBI. The aim of this study was to examine abnormal ECG findings after isolated TBI and their association with true cardiac dysfunction, based on echocardiogram.

Methods:

Data from adult patients with isolated TBI between 2003 and 2010 was retrospectively examined. Inclusion criteria included the presence of a 12-lead ECG within 24 h of admission and a formal echocardiographic examination within 72 h of admission after TBI. Patients with preexisting cardiac disease were excluded. Baseline clinical characteristics, 12-lead ECG, and echocardiogram report were abstracted. Logistic regression was used to identify the relationship of specific ECG abnormalities with cardiac dysfunction.

Results:

We examined data from 59 patients with isolated TBI who underwent 12-lead ECG and echocardiographic evaluation. In this cohort, 13 (22%) patients had tachycardia (heart rate >100 bpm), 25 (42.4%) patients had a prolonged QTc, and 6 (10.2%) patients had morphologic end-repolarization abnormalities (MERA), with each having an association with abnormal echocardiographic findings: Odds ratios (and 95% confidence intervals) were 4.14 (1.02-17.05), 9.0 (1.74-46.65), and 5.63 (1.96-32.94), respectively. Ischemic-like ECG changes were not associated with echocardiographic abnormalities.

Conclusions:

Repolarization abnormalities (prolonged QTc and MERA), but not ischemic-like ECG changes, are associated with cardiac dysfunction after isolated TBI. 12-lead ECG may be an inexpensive screening tool to evaluate isolated TBI patients for cardiac dysfunction prior to more expensive or invasive studies.