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1.
105例高原官兵心电图ST-T改变分析   总被引:3,自引:0,他引:3  
目的了解高原官兵心电图ST-T改变的发生情况及其意义。方法对2090例高原驻守官兵作常规心电图检查。对不同年龄、海拔及驻训时间进行比较。结果在2090例被检者中,ST-T改变发生率为5.02%(105/2090),各年龄组ST-T改变发生率差异无统计学意义,P〉0.05。海拔3000~3500m组ST-T改变发生率与海拔〉4000m组ST-T改变发生率差异有统计学意义,分别为3.55%(44/1240)、7.18%(61/850),P〈0.01;驻训3~6个月组与〉1年组ST-T改变发生率差异无统计学意义,分别为4.51%(72/1596)、6.68%(33/494),P〉0.05。结论高原官兵ST-T改变发病率与年龄及驻训时间无关,与驻训海拔高度相关。对ST-T改变的诊断应持慎重态度,应结合临床综合判断。  相似文献
2.
无痛胃镜及普通胃镜检查心律失常发生率的比较   总被引:3,自引:0,他引:3  
目的:对比观察无痛胃镜及普通胃镜检查心律失常发生率,探讨无痛胃镜检查的心血管安全性。方法:将300例接受胃镜检查患者随机分成无痛胃镜检查组(A组)和普通胃镜检查组(B组)(n=150),术前、术中、术后进行心电图(EKG)监测。结果:在胃镜操作前,两组心电图无差异。胃镜操作时心率增快者A组为3.3%,B组为80.6%,两组比较有显著性差异(P<0.05);窦缓A组为3.3%,B组为0%,两组比较无显著性差异(P>0.05);室性早搏A组为0.7%,B组为5.3%,两组比较有显著性差异(P<0.05);ST-T改变A组为1.3%,B组为8.0%,两组比较有显著性差异(P<0.05);室上性早搏A组为1.3%,B组为6.7%,两组比较有显著性差异(P<0.05),术后均很快恢复到术前状态。结论:无痛胃镜检查在心血管安全性方面优于普通胃镜检查,术前有EKG异常改变者建议在麻醉医师的监护下进行无痛胃镜检查。  相似文献
3.
清醒无拘束大鼠心肌缺血模型的制备   总被引:3,自引:0,他引:3  
目的 研究清醒无拘束大鼠心肌缺血模型的可靠性和准确性.方法 采用Data Science International(DSI)心电血压遥测系统记录清醒无拘束大鼠Ⅱ导联心电图(ECG),观察尾静脉注射(iv)垂体后叶素(pituitrin,Pit)后ECG T波的变化.结果 在大鼠清醒无拘束状态下,尾静脉注射垂体后叶素能够引起ECG T波的升高(P<0.01),心肌缺血模型成功建立.结论 清醒大鼠心肌缺血模型的可靠性和重复性比较好,能更客观反应受试药物的作用.  相似文献
4.
目的:观察"血瘀证"下急性心肌梗死模型与单纯急性心肌梗死模型大鼠心脏血流动力学及心电图的变化,阐明单纯急性心肌梗死模型与"血瘀证"下急性心肌梗死模型之间的差异。方法:Wistar大鼠随机分为空白对照组、急性血瘀模型组、急性心肌梗死假手术组、单纯急性心肌梗死模型组及"血瘀证"下急性心肌梗死模型组(在大鼠急性"血瘀"情况下复制急性心肌梗死模型)(每组12只),测定各组大鼠的左室收缩压(LVSP)、左室舒张末压(LVEDP)、左室压力变化最大速率(±dp/dtmax)、颈总动脉收缩压(SBP)、舒张压(DBP)及平均动脉压(MAP)等各项血流动力学指标。同时测定大鼠心率(HR)及心电图(ECG)V5导联和Ⅱ导联ST段等参数,并与单纯急性心肌梗死模型进行对比。结果:①大鼠"血瘀证"下急性心肌梗死模型与单纯急性心肌梗死模型在SBP、DBP、MAP、LVSP、LVEDP及±dp/dtmax等指标上差异无显著性(P>0.05);②大鼠"血瘀证"下急性心肌梗死模型的HR加快及V5、Ⅱ导联心电图ST段抬高程度均明显大于单纯急性心肌梗死模型组(P<0.05或P<0.01)。结论:大鼠"血瘀证"下急性心肌梗死模型与单纯急性心肌梗死模型在心电图变化上存在明显差异,在血流动力学各项指标上无明显差异,提示采用"血瘀证"下急性心肌梗死模型来评价治疗胸痹心痛中药的药效学更为合理。  相似文献
5.
T波电交替临床研究进展   总被引:2,自引:1,他引:1  
范影  黄织春 《医学综述》2008,14(1):130-133
T波电交替是指在规则的心律时,体表心电图上T波振幅、形态逐搏交替变化,与器质性心脏病恶性室性心律失常的发生有密切关系,是心肌活动不稳定的指标。在现有的检测手段及检测仪器条件下,微伏级T波电交替检测是一种价廉、方便且无创的检查形式的代表,但微伏级T波电交替检测作为一种无创的检测手段,其对于发生各种致死性心脏病危险分级的作用仍需要临床实验进一步研究证实,现就T波电交替的发生机制、临床意义、影响因素及发展现状等进行综述。  相似文献
6.
不同程度急性低氧对家兔心电图变化的比较分析   总被引:1,自引:1,他引:3  
目的 观察不同程度急性低氧对家兔心电图的影响。方法 所有的实验模型家兔中 ,以A组吸入空气为对照组 ,吸入氮氧混合气体B组为低氧 1 2 .5 %组 ,C组为低氧 8.5 %组。急性低氧时间分为 5、1 0、1 5、2 0min ,分别测定不同低氧时间的心电图变化情况。结果 两个急性低氧组心电图变化情况 :心率明显减慢 ,P波时间延长、电压降低 ;PR、QRS间期延长 ;ST段两组都抬高在基线上 ,但C组抬高较明显 ;T波电压稍降低 ;QT间期延长 ;B组R波电压较高 ,而C组较低 ;S波深度变浅。结论 急性低氧对家兔心电图的影响根据其低氧程度不同有明显的变化。  相似文献
7.
72例冠心病患者冠状动脉病变范围与心率变异性的关系   总被引:1,自引:1,他引:0  
目的:探讨冠心病(CHD)患者冠状动脉不同病变程度与心率变异性(HRV)的关系。方法:采用24h动态心电图监测,对72例CHD患者和60例正常人进行HRV时域分析和频域分析。结果:CHD组HRV各项指标均低于对照组(P<0.05),且不同冠脉病变范围和程度HRV具有显著性差异(P<0.01)。结论:CHD患者HRV明显下降,与冠脉病变范围和程度呈正相关。  相似文献
8.
Background  Potentially lethal ventricular arrhythmias (PLVAs) occur frequently in survivors after acute myocardial infarction and are increasingly recognized in other forms of structural heart diseases. This study investigated the prevalence and prognostic significance of PLVAs in patients with chronic heart failure (CHF).
Methods  Data concerning demographics, etiology of heart failure, NYHA functional class, biochemical variables, electrocardiographic and echocardiographic findings, and medical treatments were collected by reviewing hospital medical records from 1080 patients with NYHA IIIV and a left ventricular (LV) ejection fraction ≤45%. PLVAs were defined as multi-focal ventricular ectopy (>30 beats/h on Holter monitoring), bursts of ventricular premature beats, and nonsustained ventricular tachycardia. All-cause mortality, sudden death, and rehospitalization due to worsening heart failure, or cardiac transplantation during 5-year follow-up after discharge were recorded.
Results  The occurrence rate of PLVAs in CHF was 30.2%, and increased with age; 23.4% in patients <45 years old, 27.8% in those between 45–65 years old, and 33.5% in patients >65 years old (P=0.033). Patients with PLVAs had larger LV size and lower ejection fraction (both P <0.01) and higher all-cause mortality (P=0.014) during 5-year follow-up than those without PLVAs. Age (OR 1.041, 95% CI 1.004–1.079, P=0.03) and LV end-diastolic dimension (OR 1.068, 95% CI 1.013–1.126, P=0.015) independently predicted the occurrence of PLVAs. And PLVA was an independent factor for all-cause mortality (RR 1.702, 95% CI 1.017–2.848, P=0.031) and sudden death (RR 1.937, 95% CI 1.068–3.516, P=0.030) in patients with CHF.
Conclusion  PLVAs are common and exert a negative impact on long-term clinical outcome in patients with CHF.
  相似文献
9.
Background Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital heart anomaly. We aimed to illustrate the clinical features and long-term prognosis of patients with ALCAPA.Methods Twenty three patients (13 males and 10 females, ages ranging from 2.5 months to 65 years) identified as ALCAPA in Beijing Anzhen Hospital from April 1984 to June 2009 were divided into two groups, based on the age of onset: group 1 (≤12 months, n=16) and group 2 (〉12 months, n=7).Results Fifty six point three percent of patients in group 1 had been misdiagnosed as endocardial fibroelastosis (9/16),18.8% as dilated cardiomyopathy (3/16) and 6.3% as myocardial infarction (1/16). Patients in group 2 were usually diagnosed as coronary heart disease, myocarditis, or patent ductus arteriosus. Electrocardiography in group 1 revealed abnormal Q waves with T wave inversion in leads I, avL, V4-V6, especially in lead avL (deep and wide Q wave); but no specific manifestations in group 2. A higher percentage of patients in group 1 had cardiomegaly on chest radiograph (86.7% vs. 33.3%, P=0.031), while pulmonary artery protrusion was more common in group 2 (26.7% vs. 83.3%,P=0.046). Lower left ventricular ejection fraction (LVEF) was present in group 1 than in group 2 ((48.5±11.5)% vs.(65.0±6.1)%, P 〈0.001). Apical ventricular aneurysm (62.5% vs. 0%, P=0.007), enhanced echogenicity of papillary muscles (87.5% vs. 28.6%, P=0.011) and endocardial thickening (93.8% vs. 14.3%, P 〈0.001) were more frequent in group 1 than in group 2. The ratio of the proximal right coronary artery (RCA) diameter to the aortic root diameter exceeded 0.14 in all cases, more prominent in group 2 (0.26±0.05 vs. 0.33±0.03, P=0.009). Increased coronary artery collaterals within the interventricular septum were detected in 18 patients (78.3%) by Doppler imaging. Twenty one patients underwent cardiac surgery, including left coronary artery (LCA) ligation (1/21), LCA ligation plus coronary artery bypass grafting (1/21), Takeuchi operation (7/21), and LCA reimplantation surgery (12/21). Four patients underwent concomitant mitral valve repair and one received mitral valve replacement. Aneurysm resection was performed in 3 cases. Six patients died in hospital after surgery, and the rest of the cohort had no overt symptoms during a follow-up period of 6 to 166 months. Their abnormal Q waves gradually regressed or disappeared, and the LVEF and left ventricle size returned to normal range with alleviation of mitral insufficiency.Conclusions The accurate diagnosis of ALCAPA can be made with serial diagnostic methods. ALCAPA can be successfully treated with several types of cardiac surgery, and surgeries of establishing two-coronary-artery circulation are the preferred operations nowadays, with good long-term prognosis.  相似文献
10.
急性酒精中毒患者对心电图的影响   总被引:1,自引:0,他引:1  
余福玲 《中外医疗》2010,29(36):4-5
目的探讨急性酒精中毒对心电图的变化以及其临床意义。方法通过对我院2010年7~10月收治的48例急性酒精中毒患者进行心电图动态观察,并检测血压和心率情况。结果急性酒精中毒病人中心电图变化表现为PR和Q-T间期延长,对血压和心率变化并无明显影响。结论急性酒精中毒患者可导致PR间期及Q-T间期延长。  相似文献
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