Prognostic value of total ischemic burden in patients with stable ischemic heart disease.

Patients with stable coronary artery disease commonly have transient myocardial ischemia with or without experiencing angina, but the prognostic implications of this "total ischemic burden" is still a matter of debate. We studied 112 consecutive patients with coronary artery disease, normal left ventricular function at rest and exercise-induced myocardial ischemia, a 24-hour ambulatory EKG was performed after drug withdrawal. The mean exercise duration was 572 +/- 192 seconds, with an ischemic threshold (ST depression = 1 mm) of 390 +/- 190 seconds). By Holter monitoring 30 patients had no ischemia and 82 (73%) had a total of 332 episodes of ST segment changes, the majority of which were asymptomatic (242/332, 73%). Among 82 patients with transient myocardial ischemia, 44 (54%) had only asymptomatic episodes. Nine patients (11%) complained of angina coincident to ST changes. Twenty-nine patients (35%) had both painful and painless ST segment alterations. All patients were prospectively followed-up while on conventional medical therapy. During a mean follow up of 25 +/- 10 months cardiac events occurred in 31 patients; there were 5 cardiac deaths, 3 non-fatal myocardial infarctions, 2 hospitalization for unstable angina and 21 revascularization procedures (PTCA or CABG). By multivariate analysis the number of stenotic vessels on coronary angiography was predictive of the events during the follow-up (p = 0.03), while other demographic, clinical, ergometric and angiographic variables were not influential. Event-free survival was similar for all subsets of transient myocardial ischemia (silent, symptomatic, or none).(ABSTRACT TRUNCATED AT 250 WORDS)     

心电图运动试验对检测预激合并缺血性心脏病价值的探讨

对６４例无其它心血管合并症的预激综合征患者进行心电图运动试验检测．结果发现:假阳性率高达７６．６％，从而提示心电图运动试验不能作为诊断预激综合征合并缺血性心脏病的一项诊断依据。     

运动试验在冠心病临床诊断中的价值

目的评价平板运动试验（TMT）在冠心病临床诊断中的价值。方法选择我院2005年7月至2006年4月有临床症状并经冠状动脉造影（CAG）证实的冠心病患者180例，对比分析平板运动试验及冠脉造影检查结果。结果通过与冠状动脉造影（CAG）结果对比，平板运动试验检出冠心病的敏感性87．0％、特异性54．4％、准确性76．7％，并分析患者冠脉病变狭窄程度、范围及年龄、性别对平板运动试验结果的影响。结论平板运动试验具有安全、无创、价廉、操作简单等优点，对冠心病的诊断具有较高的敏感性和特异性，而且对于已明确冠心病诊断的患者，能够较准确地评估冠脉病变的严重程度、判断患者治疗效果及判断预后。     

平板运动试验对青年男性冠心病患者的诊断价值

目的 探讨平板运动试验对不同性别青年冠心病患者诊断的价值.方法 选择本院2002年6月～2006年10月住院的有典型胸痛症状的男性及女性患者各100例,分别进行平板运动试验与冠脉造影对照分析.结果 平板运动试验对青年女性冠心病诊断的特异性为49.1%,准确性为69.O%;对青年男性冠心病诊断的特异性为82.8%,准确为性92.0%.结论 平板运动试验对青年男性冠心病有较高的诊断价值,对于早期发现冠心病有重要的临床意义.     

Changes in diastolic filling of the heart during isometric exercise test in patients with ischemic heart disease treated with atenolol

Changes in left diastolic filling which had been caused by treatment with the beta-adrenoblocker atenolol given in a dose of 50-100 mg/day were studied in 66 patients with Functional Class I-II exercise-induced angina pectoris. Echocardiography was performed during isometric exercise tests before and 7-9 days after drug administration. It was ascertained that not only ino- and chronotropic mechanisms, but redistribution in diastole patterns in the direction of increasing atrial systole were involved to adequately maintain cardiac output during exercise. Ejection fraction became higher in response to exercise with predominant myocardial mass, whereas atrial systolic fraction, with predominant dilatation. The drug produced its negative inotropic effect in the patients with predominant left ventricular dilation; a decrease in the rapid filling fraction was not followed by an increase in the atrial systolic fraction, which may be regarded as an early sign of myocardial failure.     

The role of the exercise test in the evaluation of patients for ischemic heart disease

A cohort of 1472 patients who underwent both exercise stress testing and coronary angiography within six weeks was examined. The data indicated that a combination of exercise parameters is both diagnostically and prognostically important. Almost all patients (greater than 97%) who had positive exercise tests at Stage I or Stage II had significant coronary artery disease. More than half of these (greater than 60%) had three vessel disease and over 25% had significant narrowing (greater than 50%) of the left main coronary artery. Patients who achieved Stage IV or greater exercise durations with either negative or indeterminate ST-segment response had less than a 15% prevalence of three vessel disease and less than a 1% prevalence of left main coronary artery disease. A low risk subgroup (75% of all non-operated patients) was identified with a twelve month survival greater than 99%. A high risk subgroup (11% of all nonoperated patients) was identified with a twelve month survival of less than 85%. The exercise test is a noninvasive, reproducible method to assess the presence and extent of anatomic disease and the prognosis when significant disease has been defined. It should be used in conjunction with other noninvasive tests to determine optimal management in patients evaluated for ischemic heart disease.     

Prognostic significance of treadmill stress-echocardiography in patients with ischemic heart disease

Prognostic value of treadmill echocardiography was studied in 146 patients (125 men, 21 women, age 58,6-/+9 years) with overt or suspected ischemic heart disease. During 35-/+6 months of follow-up there were 26 cardiac events (11 cardiovascular deaths, 6 myocardial infarctions and 9 revascularization procedures). Independent predictors of events were presence of angina, maximal heart rate, and result of a stress test. Both exercise tolerance and echocardiographical signs of ischemia were related to development of events however the latter had better predictive power. Among patients with exercise tolerance below 7 METS with and without ischemia rates of events were 33 and 11%, respectively. Among patients with exercise tolerance above 7 METS with and without ischemia event rates were 23 and 6.8%, respectively.     

The leukergy test in patients with ischemic heart disease

In search of a simple method for potential evaluation of leukocyte aggregation in states of infarction, we compared the leukergy test, which consists of leukocyte aggregation visualized in a peripheral blood test, to the neutrophil aggregation activity (NAA) test, which consists of in vitro aggregation of neutrophils from normal donors by a patient's plasma. Seventy-five patients participated in the study; 20 with ischemic heart disease and no infarction, 41 with relatively small myocardial infarctions, and 14 with large myocardial infarctions, the respective values of leukergy being 6.9 +/- 3.2, 10.8 +/- 4.6, and 20.5 +/- 14%. On the other hand, neutrophil aggregation activity was the same in a group of 10 patients without myocardial infarction and 10 with myocardial infarction. In these two groups, which showed no difference in the NAA test, the respective leukergy values were 4 +/- 1.5 and 21.7 +/- 10.6%. Thus leukergy correlates better with the clinical picture than does the NAA test.     

Trimetazidine improves exercise tolerance in patients with ischemic heart disease

Aim

This study aimed to evaluate the effect of trimetazidine (TMZ) in addition to standard treatment on exercise tolerance in patients with ischemic heart disease (IHD).

Methods

Studies were identified via a systematic search of PubMed, Embase, Cochrane Library, and the Chinese CNKI databases from January 1978 to January 2015. Data extraction, synthesis, and statistical analysis were performed by standard meta-analysis methods. Random or fixed effects models were used to estimate pooled mean differences in total exercise duration (TED), peak oxygen uptake (pVO₂), metabolic equivalent system (METS), and 6-minute walking test (6-MWT).

Results

In all, 16 randomized controlled trials (RCTs) consisting of 2,004 participants were included. Pooled results showed that TMZ treatment significantly improved TED (WMD: 37.35, 95?% CI: 25.58–49.13, p?<?0.00001), pVO₂ (WMD: 2.41, 95?% CI: 1.76–3.06, p?<?0.00001), METS (WMD: 1.33, 95?% CI: 0.38–2.28, p?=?0.006), and 6-WMT (WMD: 62.46, 95?% CI: 35.86–89.05, p?<?0.001) in all patients with IHD. Subgroup analysis showed that TMZ significantly increased TED in nondiabetic participants (WMD 34.77, 95?% CI: 22.28–47.25, p?<?0.001), but not in diabetic participants (WMD: 40.36, 95?% CI: ??18.76–99.48, p?=?0.18). And, subgroup analysis of TED by intervention duration suggested that there is no statistically difference between the 3-month and 6-month periods (WMD: 35.47, 95?%CI: 18.35–52.60, p?<?0.0001 and WMD: 49.94, 95?%CI: 44.69–55.19, p?<?0.00001). In addition, TMZ improved TED (WMD: 50.01, 95?% CI: 44.77–55.25 and WMD: 24.20, 95?% CI: 12.72–35.68) in IHD patients with or without heart failure (HF), respectively.

Conclusion

Addition of TMZ to standard treatment significantly improved exercise tolerance in patients with IHD, and IHD patients with HF may experience even more benefits. However, there is insufficient evidence to show that TMZ has beneficial effects in participants with diabetes.

     

Serum oxidizability potential of ischemic heart disease patients is associated with exercise test results and disease severity

AIM: To find out whether serum oxidizability potential correlates with exercise test (EXT) parameters and predicts their results in chronic ischemic heart disease (IHD) patients.METHODS: Oxidizability potential was determined in a group of chronic IHD patients who underwent a symptom limited EXT upon initiation of a cardiac rehabilitation program. The thermo-chemiluminescence (TCL) assay was used to assess serum oxidizability potential. This assay is based on heat-induced oxidation of serum, leading to the formation of electronically excited species in the form of unstable carbonyls, which further decompose into stable carbonyls and light energy (low chemiluminescence). Measured photons emission is represented by a kinetic curve which is described by its amplitude and slope (= ratio). We assessed the correlations of TCL ratio with exercise duration, metabolic equivalents (METS), maximal heart rate (mHR), maximal systolic BP, > 1 mm S-T depression, diabetes, hypertension, smoking, left ventricular ejection fraction (LVEF) > or < 40%, previous myocardial infarction, and aorto-coronary by-pass surgery and compared to the TCL ratio measured in a group of healthy controls.RESULTS: A high TCL ratio (%) correlated well with METS (r = 0.84), with mHR (r = 0.79) and with exercise induced S-T segment shift (r = 0.87, P < 0.05). A lower serum oxidizability potential, expressed as a low TCL ratio, thus suggestive of a previous high oxidative stress, was found in IHD patients compared to healthy controls, and, in particular, in patients with low LVEF%. The TCL ratio (%) in IHD patients was 193 ± 21, compared to 215 ± 13 in controls (P < 0.05), and was 188 ± 14.7 in patients with LVEF < 40% as compared to 200 ± 11.9 in those with LVEF > 40% (P < 0.01). A trend for lower TCL ratio (%) was found in diabetic, hypertensive, and post-coronary bypass surgery patients. A paradoxically low TCL ratio (low oxidizability potential) was observed in patients without S-T depression compared to patients with S-T depression (189 ± 22 vs 201 ± 15, P = NS), due to the fact these patients had a much lower LVEF% and a lower exercise capacity.CONCLUSION: Serum oxidizability potential is associated with EXT parameters, results, and IHD severity. TCL ratio is an “easy-to-measure marker” that might be incorporated into risk assessment and prediction in chronic IHD patients.     

Physiologic aspects of exercise in elderly patients with ischemic heart disease

Starting from the physiological involution processes and the pathophysiological disorders of the cardiological functions, performance-limiting factors have been worked out. Any physical conditioning taking the mentioned limiting factors into account may have a function-improving and performance-improving effect (extension of the performance amplitude, economization of master in loads, psychic stabilization, reduction of risk factors, etc.). In the planning and organization of physical conditioning specific methodical aspects for training have to be taken into account, for example, preferred endurance exercises (running, walking, swimming, etc.), physiological design of the training hours, individual level of intensity, and an indication-related planning of the extent of training. Furthermore, also contra-indication have to be observed which may restrict exercise tolerance (stage of performance, regulation of blood pressure, dysrhythmia, etc.).     

Elevated CK-MB isoenzyme after exercise stress test and atrial pacing in patients with ischemic heart disease

Using a highly sensitive monoclonal antibody kit for CK-MB, significant release of small amounts of CK-MB isoenzyme after exercise stress test was detected 4 to 6 h after induction of ischemia. This occurred in ten out of 15 patients with ischemic heart disease (66 percent) and in only one of the 18 healthy subjects (5.6 percent) serving as a control group. In five patients with coronary artery disease in whom atrial pacing was performed with simultaneous blood sampling from coronary sinus, a drastic elevation in CK-MB isoenzyme (from 2.04 +/- 2.06 ng/L to 10.88 +/- 6.9 ng/L; p less than 0.001) was detected within 10 to 30 min after induction of acute ischemia. A small but significant increase in total CK also was detected (from 21 +/- 12 IU/L to 52 +/- 14IU/L; p less than 0.01). These preliminary observations have to be further investigated in a larger group of patients before a definitive conclusion can be reached about the clinical significance of CK-MB release during exercise.     

Hemodynamic shifts during physical exercise in patients with ischemic heart disease

In 82 CHD male patients aged 35-54 years with well-preserved working capacity (threshold load, 600-750 kgm/min) who had underwent bicycle ergometer test, the time course of changes in the major hemodynamic parameters was found to be significantly similar to that of healthy individuals. The cases who stopped performing bicycle ergometer tests because of anginal attacks, and ST segment depression or either showed a more significant elevation in systolic and diastolic blood pressure at the maximum load rate and lower increase in heart rate than in healthy subjects, which may be regarded as a compensatory mechanism that prevents a further decrease in coronary flow. Diminished increase in stroke index and cardiac index suggests reduced myocardial contractility.