动态心电图诊断糖尿病伴冠心病的临床价值分析

目的 比较动态心电图在糖尿病及非糖尿病人群中诊断冠心病的临床意义。方法 将188名冠心病患者分为糖尿病组(n=65)及非糖尿病组(n=123)，根据冠状动脉造影及动态心电图结果分别计算两组动态心电图的诊断敏感性、特异性等参数，并用Logistic回归分析影响动态心电图结果的因素。结果：糖尿病组动态心电图诊断冠心病的敏感性高于非糖尿病组(P=0．046)。冠脉病变血管数、有无弥漫性病变及血管完全闭塞等因素与ST段阳性改变相关(OR=2．36，4．91，3．90)。结论 虽然动态心电图的敏感性、特异性有限，但是在糖尿病合并冠心病这样一个特殊人群，仍有一定的诊断价值。     

基于USB技术的Holter系统的研究与设计

本文介绍了Holter系统的开发研究,着重介绍了其中的关键技术：低功耗的硬件设计、实时高效的算法、大容量存储设备和高速可靠的回放接口等.     

Aorto-Caval Fistula Due to Rupture of Abdominal Aneurysm

Abstract

Two operated cases of aorto-caval fistula due to ruptured abdominal aneurysm are reported. This is a rare and real surgical emergency and is fatal without operation. The classical symptoms of high-output failure occurring simultaneously with the findings of an expansible abdominal mass with thrill and bruit should facilitate clinical diagnosis.     

Dynamics of Ventricular Repolarization in Patients with Dilated Cardiomyopathy Versus Healthy Subjects

Background: Patients with impaired left ventricular function have a high risk of developing ventricular arrhythmias and sudden death. Among different markers of risk, the prolongation and regional heterogeneity of repolarization are of increasing interest. However, there are limited data regarding feasibility of analyzing repolarization parameters and their dynamics in 24‐hour Holter ECG recordings. Methods: Dynamic behavior of repolarization parameters was studied with a new automatic algorithm in digital 24‐hour Holter recordings of 60 healthy subjects and 55 patients with idiopathic dilated cardiomyopathy (IDC). Repolarization parameters included the mean value of QT and QTc durations, QT dispersion, and peaks of QT duration and QT dispersion above prespecified thresholds. Results: In comparison to healthy subjects, patients with IDC had lower heart rate variability, longer mean QT and QTc durations, higher content of QTc peaks >500 ms, longer QT dispersion and its standard deviation, and a higher content of peaks >100 ms of QT dispersion (P < 0.01 for all comparisons). These repolarization parameters were significantly higher in IDC patients after adjustment for age, sex, and heart rate variability. The parameters of repolarization dynamics correlated with SDNN in healthy subjects but not in dilated cardiomyopathy patients. Conclusions: The automatic assessment of repolarization parameters in 24‐hour digital ECG recordings is feasible and differentiates dilated cardiomyopathy patients from healthy subjects. Patients with dilated cardiomyopathy have increased QT duration, QT dispersion, and increased variability of QT dispersion reflecting variations in T‐wave morphology, the factors which might predispose them to the development of arrhythmic events.     

Circadian Rhythms of Heart Rate Variability in Hypertrophic Cardiomyopathy

Background: It has been hypothesized that an interaction between sympathetic nervous activity and an abnormal myocardium plays a role in the development and progression of hypertrophic cardiomyopathy (HCM). Methods: In the present study we investigated cardiac autonomic function by 24-hour spectral analysis of heart rate variability (HRV) in 18 patients with HCM, without evidence of heart failure, and 18 controls of similar age. Results: We found a significant reduction of 24 hour variance in HCM patients relative to controls (15,000 ± 9480 ms² vs 24,720 ± 12,450 ms² respectively; p < 0.05). Moreover, a loss of the expected day-night changes in the low frequency (LF) spectral component (expressed in normalized units), and LF/HF ratio (HF; high frequency component) were observed in HCM patients. Decreased day-night changes in LF/HF ratio were previously reported in patients with mild hypertension, uncomplicated coronary disease, and after myocardial infarction, conditions in which it seems to exist a higher than normal sympathetic activity. No significant correlations were found between HRV indices and echocardiographic standard measures of systolic and diastolic function parameters. Conclusions: These data are consistent with the presence of an alteration in neural modulation of heart period in HCM patients, noninvasively detectable by continuous 24 hour HRV analysis.     

心脏移植患者术后10年心脏自主神经功能的变化

目的 研究移植后供体心脏自主神经功能的恢复情况.方法 通过对216例心脏移植患者术后10年内24h动态心电图心率变异的随访分析,评价心脏移植术后供体心脏的自主神经功能变化.结果 移植心脏的心率变异功率频谱在术后第四年开始出现增长.亚组分析表明:35.2％的患者在术后数年内未出现明显心率变异功率谱的变化;约60％的患者在心脏移植术后第六年出现心率变异总功率谱的增加,低频功率谱增长,但高频功率谱未出现明确改变;7.4％患者心率变异功率谱在移植术后出现了明显的变化,低频和高频功率谱在术后第四年开始显著增长,超过其他患者.结论 只有为数不多的心脏移植患者在心脏移植术后逐渐出现功能性心脏自主神经功能恢复,而大多数供体心脏在术后的10年内仍保持着自主神经去神经化.     

Proximal left anterior descending coronary heart disease and complex ventricular arrhythmias

In this study, 87 consecutive patients with angiographically proven coronary artery disease (CAD, stenosis >75%) underwent 24-h Holter monitoring, 76 of them having had transmural myocardial infarction, a mean of five months before evaluation. Of the total, 51 patients showed single-vessel disease, in 31 (61%) of them with involvement of the left anterior descending (LAD) artery. In 26 patients with proximal LAD stenosis or occlusion and usually large aneurysms and subsequently impaired left ventricular function relatively low prevalence of significant ventricular premature contraction (VPC, Lown (III) was seen. On the contrary in 19 patients with multivessel disease and proximal LAD stenosis advanced forms of VPCs were present in 63% (p<0.01). Further both groups differed significantly in the frequency of postinfarction angina (30% vs. 100%; p<0.001) and their incidence in positive exercise stress tests (15% vs. 84%; p<0.001). Ejection fractions were comparable in both groups (mean 45% vs. 52%). Finally 17 patients with multivessel disease but without proximal LAD lesion did not differ in any of the above mentioned parameters, when compared to the patients with single-vessel disease and proximal LAD stenosis. We conclude that impaired left ventricular function does not sufficiently explain the high risk of sudden death in postmyocardial infarction patients. The coronary and functional status of the surviving myocardium has to be taken into consideration as well.