Influence of exercise training on spatial R-wave amplitude in patients with coronary artery disease

To evaluate the influence of an exercise program on spatial and left precordial R-wave amplitude among patients with coronary artery disease, computerized electrocardiogram (ECG) data were acquired during maximal treadmill testing before and after 1 yr in 89 patients randomized to either exercise (n = 40) or control (n = 49) groups. Spatial and lateral R-wave amplitudes were derived from the orthogonal Frank (XYZ) lead system. The exercise group significantly increased maximal O2 consumption (0.17 l/min), whereas controls decreased significantly (0.12 l/min, P less than 0.01 between groups). No significant changes in electrocardiographic R-wave voltage measurements occurred within or between groups during the year. It is concluded that exercise training does not result in increases in R-wave voltage in patients with coronary artery disease.     

A Novel Approach to Standard Techniques in the Assessment and Quantification of the Interventricular Systolic Relationship

A 51-year-old female undergoing an outpatient stress echocardiogram to evaluate atypical chest pain developed acute ST elevation in the anterior precordial leads on electrocardiogram following exercise. Echocardiography revealed a severe rise in pulmonary artery systolic pressure (PASP) with marked right ventricular (RV) enlargement and interventricular septum flattening. Subsequently, cardiac catherization confirmed an exercise-induced elevation in PASP and diagnosed pulmonary arterial hypertension without evidence of coronary artery disease. This case suggests that an acute elevation in pulmonary artery pressure with RV dilation may be a potential cause of acute ST elevation during stress testing.     

Cocaine: its use in otolaryngology

A review of 120 patients who had a discharge diagnosis of intermediate coronary syndrome showed 12 patients with documented transient ST elevation during spontaneous rest pain consistent with Prinzmetal''s angina. Coronary arteriography showed severe proximal occlusive coronary atherosclerosis in nine of the patients, and normal or minimal disease in the other three patients. In two of these three, there was documented coronary arterial spasm with reproduction of symptoms during arteriography. Although a shorter history of chest pain, presence of an old myocardial infarction and a positive finding on electrocardiogram treadmill test tended to predict the patients with severe occlusive coronary artery disease, these methods were inadequate to select candidates for arteriography. All patients responded well to nitroglycerine while in the hospital. Five of the nine patients with coronary artery disease had coronary bypass operations, with two excellent, two fair and one poor result. One of the three patients with normal findings on coronary arteriograms died with refractory ventricular arrhythmia six months after study. The other two have had good-to-moderate relief of symptoms on long-acting vasodilators and propranolol. Current concepts of the syndrome of Prinzmetal''s angina and ST elevation are reviewed. It appears that this syndrome has a wide spectrum of clinical presentations and coronary arteriographic anatomies.     

Duke Treadmill Score in prioritizing patients for coronary angiography: retrospective study of a Croatian regional hospital

Aim of the study was to determine the potential of Duke Treadmill Score (DTS) in prioritizing patients for coronary angiography in a transitional country clinical setting. We analyzed 114patients with suspected stable coronary artery disease who underwent exercise treadmill testing, and coronary angiography in Slavonski Brod General Hospital. DTS was calculated from treadmill test as: exercise time--(5 x ST deviation in mm)--(4 x exercise angina). Regarding the score, patients were grouped into three groups of risk for coronary artery disease: low risk, medium risk, and high risk patients. All patients underwent coronary angiography, and were grouped in accordance to the severity of the coronary artery disease into three groups: insignificant, significant, or severe coronary artery disease. All patients scored as high risk DTS had significant or severe coronary artery disease. Medium and low risk DTS patients had insignificant coronary artery disease in 50%, and 90% of cases, respectively. Medium risk patients with significant or severe coronary artery disease were significantly older, and had more frequent history of typical chest pain with higher number of episodes per week (P<0.05), whereas there were no differences regarding gender or presence of risk factors. There were no significant differences among medium risk patients regarding the severity of coronary artery disease in exercise time or ST deviation. However, the presence of limiting exercise angina in medium risk patients was significantly more related with significant and severe coronary artery disease (P<0.05). High risk DTS result showed great potential in stratifying patients for immediate coronary angiography. This scoring system may be used in prioritizing patients for coronary angiography in a transitional clinical setting.     

Cold pressor test in diagnosis of coronary artery disease: echophonocardiographic method.

The cold pressor test was used to induce myocardial ischaemia in patients with coronary artery disease and the rise in left ventricular filling pressure used as the index of myocardial ischaemia. Left ventricular filling pressure was derived from a non-invasive echophonocardiographic method. A study group of 19 consecutive patients with chest pain underwent the cold pressor test before coronary angiography. Eighteen responded with a rise in filling pressure exceeding 30% and, of these, 17 had serious coronary artery disease (three single vessel, one two vessel, and 13 triple vessel disease; one had coronary artery spasm only). The remaining patient, who showed no rise in filling pressure, did not have coronary artery disease. None of 15 normal controls showed a rise greater than 5% (patients with coronary artery disease versus normal controls p less than 0.001). The cold pressor test would be suitable for patients who cannot or should not exercise and may be combined with exercise electrocardiograms to improve the information content, as it uses a different marker of myocardial ischaemia.     

Myocardial ischaemia in patients with frequent angina pectoris.

One hundred patients with angina pectoris underwent 16-point electrocardiographic (ECG) mapping of the left hemithorax during a standardised exercise test. Forty-five patients had maximum ST-segment depression at position V5, while 35 had no ECG signs of ischaemia at this position. In 20 V5 was on the edge of the precordial area, which showed less severe ST-depression than the central positions. An Oxford ECG recorder and highspeed analyser were modified and used in 50 of the patients with daily angina for recording ST-segment changes over 24 hours. Serial 24-hour ambulatory recordings from the edge of the precordial area of ischaemia identified during exercise detected a mean of only 14 +/- SD 3% of the episodes of ST-segment changes recorded from the centre of the same area. Only 16 +/- 2% of the episodes detected by ECG were accompanied by chest pain. More episodes occurred between 4 am and 6 am than at any other time during the night. This study shows the importance of recording ECG evidence of ischaemia from the precordial position showing maximum changes during exercise. ECG evidence of ischaemia occurs more frequently than anginal pain. These objective measurements add important information to the frequency of chest pain reported by patients with ischaemic heart disease.     

Early exercise testing after treatment with thrombolytic drugs for acute myocardial infarction: importance of reciprocal ST segment depression.

OBJECTIVE--To investigate the clinical importance of reciprocal ST depression induced by exercise testing early after acute myocardial infarction in patients treated with thrombolysis. DESIGN--Prospective observational study. SETTING--District general hospital in London. SUBJECTS--202 patients (170 men) aged 33-69 with acute myocardial infarction treated with thrombolysis. MAIN OUTCOME MEASURES--All patients underwent exercise testing and coronary arteriography. ST depression induced by exercise was classified as either reciprocal (associated with ST elevation) or isolated (occurring on its own). The relation between reciprocal ST depression and the following end points was studied: characteristics of the infarct, left ventricular ejection fraction, extent of coronary artery disease on arteriography, and presence of angina induced by exercise. RESULTS--Reciprocal ST depression occurred almost exclusively in Q wave infarctions and was associated with a lower overall ejection fraction than isolated ST depression. It tended to be associated with persistent occlusion of the coronary artery related to the infarct and did not indicate remote ischaemia due to multivessel coronary disease. Unlike isolated ST depression, reciprocal ST depression was not associated with angina induced by exercise. CONCLUSIONS--Reciprocal ST depression induced by exercise is usually associated with extensive Q wave infarctions and persistent occlusion of the artery related to the infarct. It does not seem to indicate reversible ischaemia and should not be used as a non-invasive marker of multivessel disease in the assessment of requirements for further investigation soon after acute myocardial infarction.     

Myocardial perfusion imaging with thallium-201: correlation with coronary arteriography and electrocardiography

Myocardial perfusion imaging with thallium-201 and electrocardiography with the subject at rest and undergoing submaximal treadmill exercise were performed in 19 men and 3 women. Selective coronary arteriography and left ventriculography showed that 7 had normal coronary arteries and 15 had coronary artery disease.The 11 persons with electrocardiographic evidence of an old myocardial infarct (q waves) had a perfusion defect at rest in the area of the infarct and a segmental abnormality of wall motion apparent on the left ventriculogram corresponding to the perfusion defect.Myocardial perfusion imaging and electrocardiography were equally sensitive in detecting coronary artery disease in exercising individuals: perfusion defects were noted in 7 of the 15 persons with coronary artery disease, and diagnostic ST-segment depression was present in 8 of the 15. Combination of the results of the two tests with exercise permitted the identification of 11 of the 15 persons and improved the sensitivity. Combination of the results of rest and exercise imaging and electrocardiography permitted the identification of 94% of the patients with coronary artery disease.Myocardial perfusion imaging with ²⁰¹TI in the subject at rest is a sensitive indicator of previous myocardial infarction. Imaging after the subject has exercised is a useful adjunct to conventional exercise electrocardiography, especially in those whose exercise electrocardiogram is non-interpretable.     

Chest pain in women: clinical,investigative, and prognostic features.

OBJECTIVE--To characterise clinical, investigative, and prognostic features of women referred with chest pain who subsequently underwent coronary angiography. DESIGN--Analysis of all women with angina referred to one consultant during 1987-91 who subsequently underwent coronary angiography, with follow up to present day. SETTING--Cardiothoracic centre. SUBJECTS--Women with normal coronary arteries; women with coronary artery disease shown on angiography; men with coronary artery disease matched for age; men referred with chest pain during the same period subsequently found to have normal coronary arteries. MAIN OUTCOME MEASURES--Risk factor analysis; results of exercise testing and coronary angiography; intervention; morbidity and mortality. RESULTS--Women comprised 23% (202/886) of patients referred with chest pain who subsequently underwent angiography. 83/202 women had normal coronary angiograms compared with 55/684 men (41% v 8%, P < 0.01). Diabetes mellitus was the only risk factor more frequently encountered in women with coronary artery disease (P = 0.001). The specificity and positive predictive value of exercise testing before angiography were significantly lower in women than men (71% v 93%, P < 0.001 and 76% v 95%, P < 0.001, respectively). Revascularisation procedures were as common in women with coronary artery disease as in men (81 (68%) v 70 (59%)), and there was no difference in event rate during follow up. Many patients with normal coronary arteries, irrespective of sex, had symptoms during follow up (61 (73%) women, 36 (65%) men) and continued to take antianginal drugs (27 (33%) women, 14 (28%) men); 14 (17%) women and six (11%) men required hospital readmission for severe symptoms. CONCLUSIONS--In this series, although women comprised the minority of patients referred with chest pain, a diagnosis of normal coronary arteries was five times more common in women than men. Risk factor analysis and exercise testing were of limited value in predicting coronary artery disease in women. There was no sex bias regarding revascularisation procedures, and outcome was similar. A diagnosis of non-cardiac chest pain in patients with normal coronary arteries was of little benefit to the patient with regard to morbidity.     

Significance of fragmented QRS complexes for identifying culprit lesions in patients with non-STelevation myocardial infarction: a single-center, retrospective analysis of 183 cases

ABSTRACT: BACKGROUND: Fragmented QRS (fQRS) complexes are novel electrocardiographic signals, which reflect myocardial conduction delays in patients with coronary artery disease (CAD). The importance of fQRS complexes in identifying culprit vessels was evaluated in this retrospective study. METHODS: A 12-lead surface electrocardiogram was obtained in 183 patients who had non-ST-elevation myocardial infarction (NSTEMI) and subsequently underwent coronary angiography (CAG). On the basis of the frequency of fQRS complexes, indices such as sensitivity, specificity, positive and negative predictive values, and likelihood ratio were evaluated to determine the ability of fQRS complexes to identify the culprit vessels. RESULTS: Among the patients studied, elderly patients (age [greater than or equal to] 65 years) and those with diabetes had a significantly higher frequency of fQRS complexes (p = 0.005, p = 0.003, respectively). The fQRS complexes recorded in the 4 precordial leads had the highest specificity (81.8%) for indentifying the culprit vessel (left anterior descending artery). However, the specificity of fQRS complexes to identify lesions in the left circumflex and right coronary arteries was lower for the inferior and lateral leads than for the limb leads (65.5% versus 71.7%); however, the limb leads had higher sensitivity (92.3% versus 89.4%). And the total sensitivity and specificity of fQRS (77.1% and 71.5%) were higher than those values for ischemic T-waves. CONCLUSIONS: The frequency of fQRS complexes was higher in elderly and diabetic patients with NSTEMI. The frequency of fQRS complexes recorded in each of the ECG leads can be used to identify culprit vessels in patients with NSTEMI.     

Coronary heart disease diagnosis bases on the change of different parts in treadmill exercise test ECG

Summarize the value of the change of different parts in treadmill exercise test (TET) ECG to coronary heart disease (CHD) diagnosis. Four hundred and forty-five cases have been included in this investigation, which stayed in our hospital from January of 2006 to March of 2011 and underwent TET and coronary arteriography (CAG). The change of different parts in TET ECG in these patients had been retrospective summarized to determine its diagnosis value to CHD. (1) In the 445 cases of TET testers, 200 cases showed positive in TET with 150 cases of positive CAG, and 50 cases of negative CAG; 245 cases showed negative in TET with 206 cases of negative CAG, and 39 cases of positive CAG. The diagnosis sensitivity of CHD was 79.36 % (150/189), the specificity was 80.47 % (206/256), positive prediction value was 75.00 % (150/200), negative prediction value was 84.08 % (206/245), and false-positive rate was 25.00 % (50/200) with prediction accuracy of 80.00 % (356/445). (2) In the 200 cases with positive TET: 51 cases were in the limb lead group; 73 cases were in the chest lead group; and 76 cases were in the limb lead + chest lead group. There were 150 cases showing positive in CAG: 22 cases were in the limb lead group; 58 cases were in the chest lead group; and 70 cases were in the limb lead + chest lead group. The positive diagnosis rate of ST change in the chest lead was obviously higher than that of simple limb lead group (P < 0.05). (3) People with healthy coronary artery will have decreased amplitude of R wave while patients with coronary stenosis have elevated amplitude of R wave. (4) As for the T wave, the positive CAG had no statistical significance between normal T wave group and TET positive group (P > 0.05); CAG results had statistical significance between normal T wave group and TET negative group (P < 0.05). (5) Positive CAG results had no statistical significance between U-wave inversion group and TET positive group (P > 0.05); positive CAG results has statistical significance when TET negative group compared with U-wave inversion group or TET positive group (P < 0.05). TET is a relatively idea invasive diagnosis method for coronary disease, which can be utilized to evaluate the stage of CHD when integrating with the change of TET ECG.     

Electrocardiographic chest wall mapping in the diagnosis of coronary artery disease.

Chest wall mapping of ST segment changes, inverted U waves, and Q waves using 16 electrocardiographic electrodes was performed at rest and during and after bicycle ergometry in 150 patients presenting with chest pain suggestive of angina. All patients underwent coronary angiography. The presence or absence of appreciable coronary artery disease (greater than or equal to 50% stenosis) was detected with a sensitivity of 98% and a specificity of 88%. The identification of lesions in individual coronary arteries was also possible with a sensitivity and specificity of 87% and 85% respectively for the territory of the left anterior descending and diagonal artery, 71% and 85% respectively for the right coronary artery, and 85% and 80% respectively for the circumflex artery. This test appears to be a reliable non-invasive screening method for selecting patients for angiography.     

The value of electrocardiographic R-wave changes in exercise testing: Preexercise versus postexercise measurements

To determine the usefulness of R-wave amplitude changes during exercise testing for the diagnosis of coronary artery disease (CAD) and to understand the discrepancies that have been described in the literature regarding their value, we studied two groups of patients by means of electrocardiographic (EKG) treadmill testing and coronary arteriography. Group I was composed of 149 patients who were studied prospectively. The specificity of R-wave changes measured from preexercise to immediately postexercise (SRV(5)) was 81%, but that of R-wave changes measured from preexercise to peak exercise (URV(5)) was 46%. A group of 156 patients (Group II) evaluated retrospectively showed a high specificity for the SRV(5) (84%) and poor specificity for the URV(5) (39%). The sensitivity of the SRV(5) was 38% in Group I and 42% in Group II. Therefore, if measured during the immediate postexercise period and not at peak exercise, changes in R-wave amplitude may be of value in the diagnosis of coronary artery disease by electrocardiographic exercise testing.     

Exercise testing and training in patients with peripheral vascular disease and lower extremity amputation.

Patients with peripheral vascular disease have a high risk of coronary artery disease. The risk is even greater when the peripheral vascular disease leads to lower extremity amputation. Exercise testing using lower extremity exercise has been the "gold standard" for screening for coronary artery disease, but many patients with peripheral vascular disease and those with amputations have difficulty doing this type of exercise. Arm exercise ergometry has been shown to be a safe and effective alternative for the detection of coronary artery disease in patients who cannot do leg exercise. This test has also been used to determine safe exercise levels and may be able to predict the ultimate level of prosthetic use in amputees. Exercise training with arm ergometry also improves cardiovascular efficiency and upper body strength in poorly conditioned patients. Studies are needed to appreciate fully the role of exercise testing and training in the recovery of these patients after amputation.     

ST segment depression: the possible role of global repolarization dynamics

Background  

At least some clinical data suggests that, regardless of which major coronary artery is narrowed, the early ST segment body surface pattern is characterized by a minimum near precordial lead V5 and a broad area of left precordial negative potentials. Some clinical data also suggests that late ST segment potentials can localize an ischemic heart region.     

Combined Internal Mammary Artery Implantation and Free Omental Graft Operation: A Highly Effective Revascularization Procedure: (A Study of 17 Cases)

One hundred and forty patients with coronary artery disease treated by internal mammary artery implantation were followed up from six months to 13 years. The mortality rate was 3%; improvement was obtained in 70%. Occlusive disease of all three major coronary arteries, however, requires more blood than can be supplied by the implant procedure, and the free omental graft operation was developed for the management of selected patients with this condition. Normally in animals triple coronary artery ameroid constriction results in 100% mortality. When the free omental graft operation, with or without internal mammary artery implantation, was performed, 80% of such animals survived. The free omental graft forms capillary anastomoses in three days and arteriolar vessels in eight days, which leave the base of the aorta, enter the omentum, thence to the myocardium. A combined internal mammary artery implantation and free omental graft operation was performed in 17 patients with triple coronary artery disease as shown by cine coronary arteriography. There was no operative mortality, and 12 of the patients are free of pain and have returned to work.     

冠状动脉造影大致正常的胸痛患者临床分析

摘要 目的：探讨有胸痛症状的冠状动脉造影大致正常的患者的临床特点及病因。方法：回顾性分析2019年1月至2021年5月我院收治的有胸痛症状疑诊为冠状动脉粥样硬化性心脏病并行冠状动脉造影的1283例患者,纳入其中冠状动脉造影提示冠状动脉大致正常的患者,比较冠状动脉造影结果大致正常者与冠状动脉造影存在异常的患者的人口学资料、危险因素等,并统计冠状动脉造影结果大致正常者的确定诊断并进行分析。结果：最终纳入91例疑诊为冠心病的冠状动脉造影大致正常的患者。与冠状动脉造影存在异常的1192例患者的相比,冠脉造影大致正常组中无危险因素者占20.1%,单一高危因素者占50.5%,显著高于冠脉造影异常组,而多重高危因素者占28.6%,显著低于冠脉造影异常组（P＜0.05）。91例疑诊为冠心病的冠状动脉造影大致正常的患者中心脏神经官能症及心律失常分别占45例（49.5％）及12例(13.2％)。结论：临床上很多疑诊为冠心病的胸痛患者的冠状动脉造影大致正常,这部分患者与冠状动脉异常的患者相比冠心病的危险因素更少,胸痛由其他原因引起,所以对这部分患者应强调应用无创的检查手段。     

Reciprocal change in ST segment in acute myocardial infarction: correlation with findings on exercise electrocardiography and coronary angiography.

The clinical relevance of reciprocal changes in the ST segment occurring at the time of acute myocardial infarction was studied prospectively in 85 consecutive uncomplicated cases. Reciprocal depression of the ST segment was defined as depression of 1 mm or more in electrocardiogram leads other than those reflecting the infarct. All patients underwent maximal, symptom limited treadmill stress testing two weeks after the infarct and coronary angiography six weeks after infarction. Forty six patients had inferior, 34 anterior, and five true posterior infarction. Of the 51 patients with reciprocal changes, 45 (88%) developed exercise induced ST segment depression in areas remote from the infarction zone. At angiography all 45 patients were shown to have stenoses greater than 70% in at least two major vessels. Four patients had negative exercise electrocardiograms and were sequently shown to have single vessel disease subtending their infarct, and the remaining two patients had a false negative treadmill test result. Of the 27 patients without reciprocal changes, 21 (78%) had negative treadmill stress test results associated with single vessel coronary disease. Five had positive stress test results and multivessel coronary disease, and one had a false negative stress test result. The remaining seven patients had ST segment elevation without Q wave formation in the reciprocal areas and were assessed separately. Of these, six had positive stress test results and multivessel coronary disease and one had a negative stress test result and single vessel coronary disease to the infarct area. Twenty one patients with anterior infarcts (62%) and 27 with inferior infarcts (59%) had reciprocal changes. No differences emerged in the relation between infarct site, reciprocal change, and presence of additional coronary disease. At follow up of the 51 patients with reciprocal changes in the ST segment 36 had become symptomatic, of whom 29 had undergone coronary artery bypass surgery. By contrast, only four of the 27 patients without reciprocal changes in the ST segment had developed symptoms, and two of these had undergone coronary revascularisation. Reciprocal ST segment depression at the time of acute myocardial infarction may identify patients with severe coronary disease who are at risk of subsequent cardiac events and appears to be as reliable as results of early postinfarction treadmill stress testing in predicting the underlying coronary anatomy. When the electrocardiogram does not show reciprocal changes treadmill testing provides valuable additional information.     

低风险胸痛急性冠状动脉综合征患者心电图特征及其对诊断的价值研究

摘要 目的：分析低风险胸痛急性冠状动脉综合征(acute coronary syndrome,ACS)患者心电图特征及其对诊断的价值。方法：选择我院自2017年1月至2019年8月接诊的194例疑似低风险胸痛ACS患者,均采取心电图检查和冠状动脉造影检查;分析低风险胸痛ACS患者的心电图特征,观察心电图结果与冠状动脉病变支数、狭窄程度的关系,计算心电图诊断低风险胸痛ACS的特异性、敏感性等效能指标,使用受试者工作特征(receiver operating characteristic,ROC)曲线下面积(curve,AUC)定量分析ST段偏移值预测主要不良心血管事件的效能。结果：在194例疑似低风险胸痛ACS患者中,低风险胸痛ACS患者134例,低风险不稳定型心绞痛(UA)患者心电图表现以ST-T缺血性改变为主,发作时改变明显或呈现伪性改善;低风险非ST段抬高的心肌梗死(non-ST-segment elevation myocardial infarction,NSTEMI)患者心电图表现为肢体和胸导联ST段压低,T波低平、倒置,ST-T改变持续存在和呈动态衍变;低风险胸痛ACS患者心电图结果与冠状动脉病变支数无关(P＞0.05),与狭窄程度有关(P＜0.05);心电图诊断低风险胸痛ACS的特异性为71.67 %,敏感性为69.40 %,阳性预测值为84.55 %,阴性预测值为51.19 %,符合率为70.62 %;所有患者均获得随访,经ROC曲线分析,ST段偏移值预测低风险胸痛ACS患者发生主要不良心血管事件的最佳截值为1.85 mm,AUC为0.695,对比全球急性冠状动脉事件注册(GRACE)风险评分的0.675,差异无统计学意义(P＞0.05)。结论：低风险胸痛ACS患者心电图具有多样化,与冠状动脉狭窄程度有关,有助于初步诊断和风险评估,且ST段偏移值预测主要不良心血管事件的效能较好,值得进一步研究应用。     

Are coronary artery spasm and progressive damage to the heart associated with the hyperventilation syndrome?

A case of coronary artery vasospasm was studied in a man with a four year history of angina. He had evidence of symptomatic hyperventilation during a spontaneous episode of chest pain. When asked to hyperventilate the pain in his chest and ST elevation were reproduced in the same leads as occurred during the spontaneous attack. This may be the first reported case of spontaneous hyperventilation producing vasoconstriction, and the patient''s previous admissions to the coronary care unit may have been associated with coronary vasospasm induced by hyperventilation. When patients with variant angina report pains in the chest in association with dizziness and breathlessness hyperventilation should be considered to be a possible cause of the symptoms. As coronary vasospasm is increasingly implicated in angina after myocardial infarction the role of hyperventilation should be considered more often.