Hypertension and "silent" myocardial ischemia. I. The results of stress scintigraphy of the myocardium in patients]

As many as 24 patients suffering from essential hypertension (EH) were examined. The patients were subjected to Holter ECG monitoring, echocardiography, coronary angiography, exercise scintigraphy of the myocardium with transesophageal pacing of the atria and the dipyridamole test. The patients manifested defects of thallium accumulation during exercise scintigraphy of the myocardium. They were transitory defects of accumulation with clearance impairment recorded in EH patients with atherosclerosis of the coronary arteries; transitory defects of accumulation without clearance impairment recorded in EH patients with the angiographically unchanged coronary arteries. In Holter ECG monitoring, the patients with a silent depression of the ST segment demonstrated transitory defects of thallium accumulation by the myocardium in all the cases during exercise scintigraphy of the myocardium.     

运动中ST段下移程度不同的心肌梗死后患者的心血管反应

目的：对运动中ST段下移程度不同的心梗后患者（PMIP）的心血管反应进行探讨。方法：46名男性PMIP在跑台上进行递增负荷运动实验．其间测量每级负荷时的血压、心率并连续监测12导联心电图（ECG）。根据跑台第Ⅱ级负荷时的ST段下移程度将其分为两组．第一组ST段下移〈1．0mm．第二组ST段下移〉1．0mm。结果：定量负荷工作时ST段下移程度大的患者其心率-血压乘积（RPP）也高。结论：当不便进行ECG监测时．RPP可能是评价患者对运动的临床反应的特效指标。     

QT离散度联合ST/心率斜率及ST段标准诊断经皮冠状动脉介入术后再狭窄的研究

目的探讨心电图运动试验（EET）测定多项指标联合传统ST段标准诊断冠心病介入治疗后再狭窄的敏感性和特异性。方法2001年11月—2003年12月,对成功行经皮冠状动脉介入治疗（PCI）的129例患者在术后3-6个月进行随访,测量其EET、ST/心率斜率（ST/HRs）、QT离散度（QTd）及常规ST段阳性标准,将三者联合起来诊断PCI后再狭窄,通过冠状动脉造影确定有无再狭窄,评价其诊断再狭窄的价值。结果在传统ST段诊断标准基础上联合QTd及ST/HRs诊断再狭窄的敏感性和特异性分别为84.6%和80.4%,明显高于传统ST段诊断标准（敏感性为53.3%,特异性为66.7%,P〈0.05）。结论QTd联合ST/HRs及传统ST段标准可作为冠心病术后再狭窄的无创诊断手段。     

A comparative evaluation of loading tests for the diagnosis of ischemic heart disease at the prehospital stage

Bicycle ergometry, the treadmill test, transesophageal pacing of the left atrium and 24-h monitoring of the ECG were performed on an outpatient basis in 82 persons (all men) with angina pectoris of effort and stenosing atherosclerosis of the coronary arteries verified with the aid of selective coronarography and in 17 men with intact coronary arteries. Transesophageal pacing and the treadmill test exhibited the highest sensitivity (94 and 89%, respectively) in the diagnosis of the latent forms of coronary failure. The sensitivity of bicycle ergometry (77%) was significantly lower which was caused by a considerable number (21%) of tests completed before the appearance of diagnostic criteria. Meanwhile the results of 24-h monitoring of the ECG (65% sensitivity) depended on the degree of the patients' physical activity and way of life. All the four methods did not significantly differ in the specificity. Proceeding from the data obtained it is recommended that the treadmill test and transesophageal pacing of the heart may be widely used on an outpatient basis to diagnose coronary disease.     

Ambulatory monitoring of silent myocardial ischemia: what is its utility?

In patients with angina pectoris, ambulatory ST segment monitoring has documented that asymptomatic myocardial ischemic episodes occur with greater frequency than previously suspected. During such episodes, ischemia has been verified by nuclear, echocardiographic, and biochemical techniques. Painless ST segment depression is consistent with severe coronary artery disease when detected by ambulatory monitoring in patients with angina and portends a worsened prognosis in patients about to have vascular surgical procedures. On the other hand, ST depression without angina has a better prognosis than ST depression with angina during treadmill exercise testing. Silent ischemia of prolonged duration per 24-hour period suggests a poor prognosis in patients with a history of unstable angina or myocardial infarction.     

ST/HR指数联合常规ST段标准提高心电图运动试验对冠状动脉介入术后再狭窄诊断的研究

目的探讨通过心电图运动试验测定ST/HR指数联合常规ST段标准诊断冠状动脉介入术后再狭窄的敏感性和特异性.方法对成功行冠状动脉介入治疗的129例患者,在术后3～6个月进行随访,心电图运动试验测量ST/HR指数及常规ST段阳性标准二者联合诊断再狭窄,通过冠状动脉造影确定有无再狭窄,评价其诊断再狭窄的价值.结果二者联合应用诊断再狭窄的敏感性和特异性分别为75.0%和83.3%,高于传统ST段标准（53.3%和66.7%）（均P＜0.05）.结论联合应用ST/HR指数及常规ST段标准可作为诊断再狭窄的无创手段.     

平板运动试验ST段压低恢复时期的假阳性表现

目的：对照平板运动试验与冠状动脉造影结果．探讨影响运动试验正确诊断冠心病的因素，从而提高冠心病诊断的准确性。方法：选择资料完整的156例行平板运动试验与冠状动脉造影的患进行结果对照。观察运动引起ST改变与冠状动脉造影之间的联系。结果：156例平板运动试验敏感性77％，特异性30％，假阳性率36％，其中36例女性平板运动试验敏感性71％，特异性27％．假阳性率61．5％。在42例假阳性患中，26例ST段压低在恢复期即刻恢复至原来状态。绝大多数女性运动试验假阳性ST段压低均在恢复期即刻恢复至原来状态。结论：平板运动试验是检测冠心病的有效方法。在平板运动试验中假阳性患大半数ST段压低在恢复期即刻恢复，提示假阳性与女性及ST段压低在恢复期即刻恢复有关。     

Which diagnostic tests are most useful in a chest pain unit protocol?

Background

The chest pain unit (CPU) provides rapid diagnostic assessment for patients with acute, undifferentiated chest pain, using a combination of electrocardiographic (ECG) recording, biochemical markers and provocative cardiac testing. We aimed to identify which elements of a CPU protocol were most diagnostically and prognostically useful.

Methods

The Northern General Hospital CPU uses 2–6 hours of serial ECG / ST segment monitoring, CK-MB(mass) on arrival and at least two hours later, troponin T at least six hours after worst pain and exercise treadmill testing. Data were prospectively collected over an eighteen-month period from patients managed on the CPU. Patients discharged after CPU assessment were invited to attend a follow-up appointment 72 hours later for ECG and troponin T measurement. Hospital records of all patients were reviewed to identify adverse cardiac events over the subsequent six months. Diagnostic accuracy of each test was estimated by calculating sensitivity and specificity for: 1) acute coronary syndrome (ACS) with clinical myocardial infarction and 2) ACS with myocyte necrosis. Prognostic value was estimated by calculating the relative risk of an adverse cardiac event following a positive result.

Results

Of the 706 patients, 30 (4.2%) were diagnosed as ACS with myocardial infarction, 30 (4.2%) as ACS with myocyte necrosis, and 32 (4.5%) suffered an adverse cardiac event. Sensitivities for ACS with myocardial infarction and myocyte necrosis respectively were: serial ECG / ST segment monitoring 33% and 23%; CK-MB(mass) 96% and 63%; troponin T (using 0.03 ng/ml threshold) 96% and 90%. The only test that added useful prognostic information was exercise treadmill testing (relative risk 6 for cardiac death, non-fatal myocardial infarction or arrhythmia over six months).

Conclusion

Serial ECG / ST monitoring, as used in our protocol, adds little diagnostic or prognostic value in patients with a normal or non-diagnostic initial ECG. CK-MB(mass) can rule out ACS with clinical myocardial infarction but not myocyte necrosis(defined as a troponin elevation without myocardial infarction). Using a low threshold for positivity for troponin T improves sensitivity of this test for myocardial infarction and myocardial necrosis. Exercise treadmill testing predicts subsequent adverse cardiac events.     

Electrocardiographic ST‐segment depression in children with Fontan circulation

Despite successful operation, many patients palliated with a Fontan‐type procedure continue to show effort limitation. We previously observed that these children showed electrocardiographic ST depression during exercise tests. The purpose of the study was to investigate whether electrocardiographic ST depression is a common finding in children with Fontan circulation. Forty‐two children in two groups were examined: group A consisted of 14 patients who had all undergone a modified Fontan procedure, and group B consisted of 28 children with a structurally normal heart, matched for length, weight and gender to group A. Complete echocardiographic examinations were performed in all patients and controls. All 14 patients and all 28 healthy children underwent standard 24 h ambulatory electrocardiographic monitoring. All the recordings were analysed by a PC‐based Holter system where an analysis of ST changes was performed. Seven patients and 14 matched healthy children were exercised on bicycle ergometers. Four patients and eight matched healthy children underwent exercise testing by walking/running a treadmill. Ten of 13 patients analysed had significant ST depressions on ambulatory electrocardiogram (>0·20 mV). Three of the 10 patients with ST depression were on digoxin. Three patients showed depressions of the ST segment in the electrocardiogram during exercise, with a maximal depression of 0·20–0·35 mV. None of the 28 matched healthy children showed electrocardiographic ST depression on the ambulatory 24 h ECG. These findings indicate that ST depression in daily activity is a common finding in children with Fontan circulation.     

十二导联心电图对左主干病变导致急性冠状动脉综合征的诊断价值

目的探讨十二导联心电图对左主干病变导致急性冠状动脉综合征（ACS）的诊断价值。方法37例ACS患者根据冠状动脉造影结果分为A组（左主干病变导致ACS组）17例和B组（左前降支近段病变导致ACS组）20例,2组患者胸痛发作时均行十二导联心电图检查,分析冠状动脉病变血管与相应心电图变化的关系。结果A组在Ⅱ、Ⅲ、aVF、V2、V3、V4、V5、V6导联上相应ST段压低的发生率高于B组（P〈0．05或P〈0．01）。A组ST段在aVR、V1导联抬高并aVF、V2、V4导联压低发生率高于B组（P〈0．05）。结论十二导联心电图上aVR、V1导联ST段抬高并aVF、V2、V4导联压低对ACS患者左主干病变有较好的阳性预测价值。     

24-hour ECG monitoring in cardiac fibrillation

AIM: To elucidate clinical value of 24-h ECG monitoring followed by analysis of cardiac rhythm structure in patients with perpetual cardiac fibrillation (CF). MATERIALS AND METHODS: 24-h ECG monitoring has been performed 163 times in 142 patients aged 33-82 years. Interval histograms and cardiointervalograms of R-R intervals were performed. RESULTS: 24-h ECG monitoring has shown the phenomena which can be used for perfection of the diagnosis and treatment: features of 24-h changes in heart rate; features of ventricular ectopy; periods of asystole; preclinical signs of hyperdigitalization; frequency-related shift of ST segment. CONCLUSION: 24-h ECG monitoring in patients with perpetual CF provides valuable diagnostic information. Therefore, it should be conducted in all of them irrespective of subjective state and routine ECG data, especially in deciding on antiarrhythmic therapy.     

Ambulatory ECG monitoring. How useful in detecting and quantitating transient ischemia?

ST segment shifts are reliable indicators of transient myocardial ischemia. Ambulatory ECG monitoring detects episodes of ST segment shift with and without chest pain in patients with coronary heart disease. Monitoring can provide valuable information on the presence and frequency of transient myocardial ischemia. Limited information is available on the use of ambulatory monitoring as a screening test, particularly in populations where the frequency of coronary heart disease is low.     

变异型心绞痛12例临床分析

目的:分析变异型心绞痛的临床特点及治疗方法。方法:根据在静息状态下发生心绞痛,床旁12导联体表心电图或动态心电图监测证实心绞痛发作时ST段抬高,胸痛缓解后ST段恢复至基线,有12例患者确诊为变异型心绞痛。分别从性别、年龄、临床表现、冠心病危险因素、辅助检查及治疗进行分析。结果:该病好发于男性(占91．7％),发病时平均年龄为56岁,除吸烟外,多无其他的冠心病危险因素,心绞痛多于凌晨静息时发作,含服硝酸酯类药物有效,5例(占41．6％)发病时并发室性心动过速及高度房室传导阻滞恶性心律失常,8例(占83％)冠状动脉有固定性狭窄,硝酸酯类药物与钙通道阻滞剂可有效防止复发,支架植入有效。结论:静息状态下特别是清晨时发生胸痛的患者,胸痛时应及时行心电图检查以诊断或排除变异型心绞痛,变异型心绞痛恶性心律失常发生率高,需及时诊断治疗,硝酸酯类药物多可缓解症状,硝酸酯类药物与钙通道阻滞剂可有效防止复发,较高比例的患者有冠状动脉严重的固定性狭窄,变异型心绞痛患者均应行冠脉造影术检查,对有严重狭窄者可行支架植入以有效地治疗心绞痛。     

康复训练对冠心病患者介入治疗后的运动耐量的影响

目的 察康复训练对冠心病经皮冠状动脉介入治疗（PCI）后患者运动耐量的影响。方法 确诊为冠心病并成功进行了首次PCI的患者57例，随机分为运动康复组（26例）和对照组（31例）．2组患者除行PCI治疗外，均采用相似的常规疗法（口服肠溶阿司匹林、硝酸酯类、转换酶抑制剂或他汀类药物等）。运动康复组于PCI术后第3天开始进行不同阶段、不同运动强度的康复训练，运动分为热身期，锻炼期、恢复期。3个月后，行心电图活动平板运动试验。观察活动平板运动试验运动前、运动中的心率、血压、心电图改变及心绞痛发作情况。结果 运动康复治疗3个月后，运动康复组与对照组静息及运动时心率、收缩压、舒张压、心率-血压双乘积差异无统计学意义（P〉0．05），其总运动时间、运动至出现S段压低1mm时间、运动至心绞痛出现时间与对照组相比明显延长（P〈0．05或P〈0．01），最大运动耐量明显增加（P〈0．05或P〈0．01）。结论 照运动处方进行的运动训练能明显缓解冠心病介入治疗后患者心绞痛症状及改善心电图缺血性S—T变化，提高冠心病介入治疗后患者的运动耐量，延长运动时间。     

Significance of ST depression during exercise treadmill stress and adenosine infusion myocardial perfusion imaging

Background: ST segment depression on the electrocardiogram during the exercise treadmill test (ETT) is used as a predictor of coronary artery disease (CAD), although it is recognised that both false-positive and false-negative results limit the value of this procedure. Although adenosine does not produce an inotropic or chronotropic effect upon the myocardium it may cause ST depression during infusion. Methods: The 12-lead ECG recordings obtained during 825 adenosine stress and 425 ETT procedures, performed as part of a 2-day Tc-MIBI protocol, were retained for examination and comparison with the appearances at subsequent myocardial perfusion imaging (MPI). Results: ST depression was associated with 44 (4.9%) of the adenosine stress and 44 (10.4%) of the ETT procedures. Both 1 and 2 mm ST depression during adenosine stress were significant predictors of reversible ischaemia (p < 0.01; p < 0.01). However, even though 2 mm ST depression on ETT was significant as a predictor of reversible ischaemia (p < 0.01), 1 mm ST depression on ETT was not (p = 0.4). There were more female cases with false positive ECG changes in both the adenosine stress (63.6%) group and the ETT (66.7%) group. There was no significant correlation between the territory of the ischaemic changes seen on the ECG with the location of defects developing on MPI in both the adenosine stress and ETT groups.Conclusions: ST depression of 1 mm occurring with adenosine stress, unlike with the ETT, is a significant predictor of ischaemia.     

Serial Electrocardiograms for Chest Pain Patients with Initial Nondiagnostic Electrocardiograms: Implications for Thrombolytic Therapy

Objectives: To determine the proportion of acute myocardial infarction (AMI) patients without ST–segment elevation who subsequently develop ST–segment elevation during their hospital courses; and to compare demographics and presenting features of AMI patient subgroups: those with initial ST–segment elevation, those with in–hospital ST–segment elevation, and those with no ST–segment elevation. Methods: A retrospective cohort analysis of admitted chest pain patients who had a hospital discharge diagnosis of AM1 was performed. Each chart was examined for initial ECG interpretation, serial ECG analysis, patient age, gender, cardiac risk factors, in-hospital survival, time between sequential ECGs, and number of ECGs performed within the first 48 hours of hospital admission. Results: Of the 114 charts reviewed, 20 patients had ECGs meeting thrombolytic criteria on arrival. Of the 94 AM1 patients who had nondiagnostic ECGs on arrival, 19 (20%) subsequently developed ECG changes meeting thrombolytic criteria. Seven patients developed these changes within eight hours of the initial ECG, four from eight to 12 hours after, two from 12 to 24 hours after, and six more than 24 hours after. Most patients who had documented AMIs did not develop ECG criteria for thrombolytic therapy during their hospitalizations. Male gender and smoking history were more commonly associated with late ST-segment elevation for those presenting with nondiagnostic ECGs. All the patients who had late diagnostic ECG changes survived to hospital discharge. Serial ECGs were performed more frequently in the group who had initially diagnostic ECGs and least frequently in the group who did not develop ST-segment elevation during their hospitalizations. Conclusions: Most patients with AM1 do not meet ECG criteria for the administration of thrombolytic therapy. A significant minority (20%) of the admitted chest pain patients with subsequently confirmed AMIs developed ECG criteria for thrombolytics during their hospitalizations. Further attention to such patients who have delayed ST-segment elevation is warranted. A standardized in-hospital serial ECG protocol should be considered to identify admitted patients who develop criteria for thrombolytic or other coronary revascularization therapy.     

Esophageal diseases in patients with stenocardia and angiographically changes and little-changed coronary arteries

Angiography conducted in 29 anginal patients has shown that coronary arteries were intact in 23 and little affected in 6 of them. Signs of myocardial ischemia were recorded at myocardial scintigraphy, bicycle ergometry, 24-h ECG monitoring in 17 patients. Esophageal lesions confirmed by endoscopy, manometry, esophageal pH-metry with Bernstein test were revealed in 20 examinees (68%). It is suggested that patients with persistent chest pain and unaffected coronary arteries who are resistant to antianginal therapy should undergo functional study of the esophagus including endoscopy, manometry and pH-metry.     

平板运动试验在诊断女性冠状动脉疾病中的临床意义

目的：评价平板运动试验(treadmill exercise testing，TET)在诊断女性冠状动脉疾病(coronary artery disease，CAD)中的应用价值。方法：回顾性分析1995年3月-2002年11月在本院作冠状动脉造影(coronary arteriography,CAG)并同时行TET检查的104例女性患的临床资料。TET检查采用日本国立心血管疾病中心(NCVC)制定的方案，评价指标包括ST段压低程度、运动后3min收缩期血压(SBP)与运动高峰时SBP比值[SBP比(3’)]和是否发生心绞痛(angina pectoris，AP)。结果：单用ST段压低作为诊断指标，其灵敏度为98．2％，特异度为4．2％；ST段压低结合SBP比(3’)时，其灵敏度为83．9％，特异度为89．6％；ST段压低结合AP作为诊断指标，其灵敏度为89．3％．特异度为95．8％。结论：ST段压低与SBP比(3')及AP的综合评估可提高TET对女性CAD的临床诊断的准确性。     

急性下壁心肌梗死患者的临床特点分析

目的 分析研究急性下壁心肌梗死患者的临床特点. 方法 将急性下壁心肌梗死患者100例根据冠状动脉造影结果分为两组:76例为右冠状动脉(RCA)闭塞(A组),24例为左回旋支冠状动脉(LCX)闭塞(B组). 结果 心电图ST段抬高STⅢ>STⅡ及ST段压低STAVL>ST I A组显著高于B组(均P<0.05);ST段抬高STⅢ0.1 mV A组显著高于B组(P<0.05);胸前导联V1～6ST段压低患者中,合并左前降支冠状动脉(LAD)病变的患者显著高于胸前导联V1～6ST段无压低者(P<0.05);左心室射血分数(LVEF)A组[(51±14)%]显著低于B组[(57±10)%](P<0.05);合并右心室心肌梗死A组显著高于B组(P<0.05);急性下壁心肌梗死患者总的住院病死率6%,均为A组,但心源性休克、心力衰竭、Ⅱ、Ⅲ度房室传导阻滞,室性心动过速/心室颤动及住院病死率,两组差异均无统计学意义(均P>0.05);死亡者中心源性休克占83.3%. 结论 心电图Ⅲ、Ⅱ、I、AVL、及V4R导联ST段变化能预测急性下壁心肌梗死相关血管,急性下壁心肌梗死患者伴胸前导联ST段压低提示LAD病变,RCA闭塞所致下壁心肌梗死LVEF低于LCX闭塞者,心源性休克为死亡主要原因.     

A pilot study of continuous ambulatory electrocardiography in patients donating blood for autologous use in elective coronary artery bypass grafting

BACKGROUND: A pilot study was conducted to evaluate the impact of a single autologous blood donation on the presence or absence of myocardial ischemic episodes in patients with coronary artery disease. STUDY DESIGN AND METHODS: Fifty patients scheduled for elective coronary artery bypass grafting underwent two 24-hour periods of ambulatory electrocardiogram monitoring, one before and one after their first autologous blood donation. The presence or absence and the number, duration, and integral area of episodes of ST segment depression for each 24-hour monitoring period were determined. RESULTS: Forty-two patients had legible electrocardiogram recordings for both monitoring periods. Of these, 36 patients (86%) had at least one episode of ST segment depression during any monitoring period. The number of patients who had at least one episode of ST segment depression before donation was not significantly different from the number of those who had at least one episode after donation (31 and 33 patients, respectively; p = 0.73). CONCLUSION: Donating a unit of blood had no demonstrable effect on the presence or absence of myocardial ischemic episodes in this sample of 42 autologous blood donors with coronary artery disease. The results of this study should be validated in further trials.