Transient ST-segment Depression Research Articles

Extension of interval between adjacent pulse delivery cycles to deal with myocardial ischemia by intravascular lithotripsy: case report

BackgroundIntravascular lithotripsy (IVL) represents a novel approach in the management of coronary calcification. This technique employs acoustic pressure waves, generated by a shockwave balloon, to effectively fracture both superficial and deep calcification in situ. The efficacy and safety of IVL have been convincingly demonstrated through the Disrupt CAD I-IV studies. While IVL is associated with the occurrence of atrial and ventricular arrhythmias, there is no evidence to indicate it causes myocardial ischemia.Case DescriptionA 71-year-old man was admitted presenting with chest pain. His previous coronary angiography revealed stenosis and calcification in the left anterior descending branch. An attempt to predilate the lesion using two Lacrosse non-slip element balloons was unsuccessful. Ventricular premature beats and transient ST-segment depression were captured during the utilization of IVL. The operator gradually extended the pulse emission interval across two consecutive cycles to mitigate myocardial ischemia. Notably, when the interval reached 30s, the patient had no chest pain or ST-segment changes. Subsequent images of intravascular ultrasound confirmed calcification ruptures. Therapeutic intervention included the placement of a stent and the application of a drug-coated balloon in the left anterior descending branch. A telephonic follow-up six months later indicated the patient had no discomfort.ConclusionsThis case underscores the effectiveness of gradually extending the pulse emission interval as a strategic complement to the clinical application of IVL. In certain clinical scenarios, it may become imperative to suspend the pulse delivery to improve myocardial blood supply.

Vasospastic angina: a review on diagnostic approach and management.

Vasospastic angina (VSA) refers to chest pain experienced as a consequence of myocardial ischaemia caused by epicardial coronary spasm, a sudden narrowing of the vessels responsible for an inadequate supply of blood and oxygen. Coronary artery spasm is a heterogeneous phenomenon that can occur in patients with non-obstructive coronary arteries and obstructive coronary artery disease, with transient spasm causing chest pain and persistent spasm potentially leading to acute myocardial infarction (MI). VSA was originally described as Prinzmetal angina or variant angina, classically presenting at rest, unlike most cases of angina (though in some patients, vasospasm may be triggered by exertion, emotional, mental or physical stress), and associated with transient electrocardiographic changes (transient ST-segment elevation, depression and/or T-wave changes). Ischaemia with non-obstructive coronary arteries (INOCA) is not a benign condition, as patients are at elevated risk of cardiovascular events including acute coronary syndrome, hospitalization due to heart failure, stroke and repeat cardiovascular procedures. INOCA patients also experience impaired quality of life and associated increased healthcare costs. VSA, an endotype of INOCA, is associated with major adverse events, including sudden cardiac death, acute MI and syncope, necessitating the study of the most effective treatment options currently available. The present literature review aims to summarize current data relating to the diagnosis and management of VSA and provide details on the sequence that treatment should follow.

Systems Thinking

Systems Thinking

Akutni koronarni sindrom bez perzistentne elevacije ST segmenta - šta su NAM donele nove preporuke

Acute myocardial infarction without persistent ST-segment elevation is a serious medical problem that significantly increases cardiovascular mortality and morbidity. Therefore, timely accurate diagnosis is crucial for adequate treatment of these patients, better survival and improved quality of life. It is characterized by a clinical picture of acute chest discomfort that may occur in the form of typical anginal problems or as the equivalent of acute chest pain. Changes in the electrocardiogram are varied, from transient ST-segment elevation, persistent or transient ST-segment depression, T-wave inversion, flattened T-wave, or pseudonormalization of the T-wave, to normal electrocardiographic recording. The latest guidelines of the European Society of Cardiology advise determining the value of cardio-specific enzymes from the patient's blood, namely high-sensitivity cardiac troponin T or I immediately upon admission to the health institution and repeated one hour after admission (0h / 1h algorithm). Echocardiographic examination is recommended in all patients as a routine procedure before admission or during hospitalization. Coronary CT angiography for the anatomical evaluation of coronary heart disease is important in patients with a low to moderate probability of an acute coronary event. Drug treatment in these patients involves the use of dual antiplatelet therapy to determine the ischemic risk of the patient as well as the risk of bleeding. Pre-treatment with the use of primarily P2Y12 receptor inhibitors is not recommended in routine clinical practice. In patients who have undergone revascularization and stent implantation, dual antiplatelet therapy is recommended for 12 months, except in cases where there are contraindications or increased hemorrhagic risk. Patients who require long-term use of oral anticoagulant therapy after a short period of triple antiplatelet therapy up to 1 week after the acute event, continue dual antiplatelet therapy, using new anticoagulants at the recommended dose to prevent stroke and one oral antiplatelet drug. Invasive coronary angiography can be performed according to the patient's risk immediately after admission to a health institution (within 2 hours) in very high-risk patients or as an early treatment strategy, within 24 hours of admission in high-risk patients. To perform an invasive intervention, a radial approach is advised, as well as the implantation of drug-coated stents. In patients in whom it is not possible to perform myocardial revascularization by percutaneous coronary intervention, revascularization with coronary artery bypass grafts is recommended. In the long-term follow-up of these patients, after an acute coronary event, it is advisable to change life habits with pharmacological treatment, which reduces mortality and improves the quality of life.

Association between Ischemic Electrocardiographic Changes during Acetylcholine Provocation Test and Long-Term Clinical Outcomes in Patients with Vasospastic Angina

Objectives Intracoronary injection of acetylcholine (Ach) has been shown to induce significant coronary artery spasm (CAS) in patients with vasospastic angina. Clinical significance and angiographic characteristics of patients with ischemic electrocardiogram (ECG) changes during the Ach provocation test are not clarified yet. Methods A total 4,418 consecutive patients underwent coronary angiography with Ach provocation tests from 2004 to 2012 were enrolled. Ischemic ECG changes were defined as transient ST-segment depression or elevation ( > 1 mm) and T inversion with/without chest pain. Finally, a total 2,293 patients (28.5% of total subjects) proven CAS were enrolled for this study. Results A total 119 patients (5.2%) showed ECG changes during Ach provocation tests. The baseline clinical and procedural characteristics are well balanced between the two groups. Ischemic ECG change group showed more frequent chest pain, higher incidence of baseline spasm, severe vasospasm, multi-vessel involvement, and more diffuse spasm ( > 30 mm) than those without ischemic ECG changes. At 5 years, the incidences of death, major adverse cardiac events (MACE) and major adverse cardiac and cerebral events (MACCE) were higher in the ischemic ECG change group despite of optimal medical therapy. Conclusions The patients with ischemic ECG changes during Ach provocation tests were associated with more frequent chest pain, baseline spasm, diffuse, severe and multi-vessel spasm than patients without ischemic ECG changes. At 5-years, the incidences of death, MACE and MACCE were higher in the ischemic ECG change group, suggesting more intensive medical therapy with close clinical follow up will be required.

Clinical and ECG patterns of pseudoinfarction in a young man with type 1 diabetes, diabetic ketoacidosis and normokalaemia

Diabetic ketoacidosis (DKA) can cause changes in the electrocardiogram (ECG) in the form of transient ST-segment depression, QT prolongation, changes in T-wave morphology and the appearance of U wave, possibly due to changes in the serum potassium level. Occasional reports indicate the possibility of transient ST-segment elevation imitating myocardial infarction in the course of hyperkalaemia accompanying DKA. In this article we present a case of a 20-year-old male patient with type 1 diabetes mellitus, DKA and normokalaemia, who experienced severe retrosternal pain, and ECG presented ST-segment elevation imitating acute myocardial infarction of the anterior wall. On the basis of the performed cardiac tests, including laboratory testing, coronary angiography and ultrasound scan, acute coronary syndrome was ruled out. The regression of retrosternal pain and electrocardiographic changes with patient hydration and correction of metabolic disorders suggest the diagnosis of pseudopericarditis, i.e. non-infections irritation of the pericardial membranes due to the loss of fluid in the pericardial sac as a result of dehydration. The diagnosis of acute myocardial infarction based on ST-segment elevation in the ECG recording in a patient with diabetes mellitus and ketoacidosis, without concomitant hyperkalaemia, must be made very carefully, even in the presence of retrosternal pain. The possibility of pseudopericarditis associated with severe dehydration must also be considered.

Acute Coronary Syndromes Presenting with Transient Diffuse ST Segment Depression and ST Segment Elevation in Lead aVR not Caused by “Acute Left Main Coronary Artery Occlusion”: Description of Two Cases

Diffuse ST-segment depression in the inferior + anterolateral leads with ST-segment elevation in lead aVR has been described as characteristic of diffuse circumferential subendocardial ischemia caused by acute subtotal occlusion of the left main coronary artery. Here we describe two patients admitted for acute neurological disorders who developed transient diffuse ST-segment depression in the inferior + anterolateral leads with ST-segment elevation in lead aVR, associated with elevation of cardiac troponin-I. In both cases subsequent coronary angiography did not show significant left main stenosis or "left main equivalent" narrowings. As both patients had acute neurological disorders, a possible association between the two conditions is discussed.

Impaired myocardial perfusion in atrial fibrillation cause or effect?

This editorial refers to ‘Myocardial perfusion imaging does not adequately assess the risk of coronary artery disease in patients with atrial fibrillation’ by M.D. Smit et al. , on page 643. Atrial fibrillation (AF) is the most common sustained arrhythmia, particularly in the elderly. It is associated with increased morbidity and mortality and frequently requires pharmacological (antiarrhythmic drugs) or interventional (catheter ablation) therapy.1 Patients with AF frequently present with angina-like chest pain and transient ischaemic-type ST-segment depression, irrespective of ischaemic, non-ischaemic, or idiopathic origin of AF. In addition, elevated markers of myocardial damage have been reported after cardiac decompensation due to tachyarrhythmias. However, these findings were not always associated with significant coronary artery disease. Atrial fibrillation is more likely to develop on the basis of structural heart disease such as coronary artery disease, dilated cardiomyopathy (DCM), valvular heart disease, and others. In patients with pre-existing left ventricular dysfunction, AF may further diminish cardiac performance and aggravate heart failure, resulting in more frequent hospitalizations and impaired prognosis. On the other hand, restoration and maintenance of sinus rhythm may improve myocardial perfusion and perfusion reserve resulting in amelioration of left ventricular function. Patients with AF and concomitant coronary artery disease are at increased risk of cardiovascular impairment and complications. Therefore, the early identification and appropriate treatment of ischaemic heart disease underlying the arrhythmia is of major clinical and prognostic importance. However, non-invasive diagnosis of coronary artery disease is hampered in patients … *Corresponding author. Tel: +49 541 326 4662; fax: +49 541 326 4105, Email: thomas.wichter{at}mho.de

Angina de Prinzmetal

This syndrome is due to focal spasm of an epicardial coronary artery, leading to severe myocardial ischemia. Although it is frequently thought that the spasm occurs in arteries without stenosis, many Prinzmetal patients have spasm adjacent to atheromatous plaques. The exact cause of the spasm has not been well defined, but it may be related to the hypercontractility of the vascular smooth muscle due to vasoconstrictor mitogens, leukotrienes, or serotonin. In some patients, it is a manifestation of a vasospastic disorder and it is associated with migraine, Raynaud's phenomenon, or aspirin-induced asthma. We present a case associated with transient ST-segment depression.

Electrocardiographic presentations of left main or severe triple vessel disease in acute coronary syndromes—an overview

Abstract The prognosis of high-risk patients with non-ST-elevation acute coronary syndrome can be improved by invasive therapy. Taking into account the large number of patients with symptoms suggestive of acute coronary syndrome, the heterogeneity of the population and the increased risk of events shortly after the onset of symptoms, a strategy for initial evaluation and treatment is essential. The electrocardiogram (ECG) is the most accessible and widely used diagnostic tool for patients with symptoms suggestive of acute myocardial ischaemia. The ECG is almost never normal during episodes of rest angina. A specific ECG pattern, transient ST-segment depression and negative T waves maximally in leads V4-5, is associated to left main or severe triple vessel disease, and should alert the treating physician to admit the patient for immediate invasive evaluation. The ECG finding is a result of severe wide-spread subendocardial ischaemia.

Myocardial ischemia during everyday life in patients with arterial hypertension: prevalence, risk factors, triggering mechanism and circadian variability

The objective of the present study was to investigate the prevalence, the risk factors, the hemodynamic triggering mechanisms, the circadian variability of ST segment depression (ST depression) and the effect of day and night fall in blood pressure on the prevalence of ST depression in hypertensive patients. In a multicentric study in Germany, 1,244 CardioTens registrations (combined 24-h ambulatory blood pressure measurement/electrocardiography with ST segment triggering; Meditech, Budapest, Hungary) from patients with arterial hypertension were consecutively monitored and evaluated centrally at the University of Bonn. Inclusion criterion was treated or untreated arterial hypertension. The ST segment was measured in accordance with the "1 : 1 : 1 rule" (horizontal or descending ST depression by 1 mm, 1 min duration, 1 min interval from the previous episode). ST segment depression was observed in 250 (20.1%) patients; 90.3% of the transient ST-segment depression was silent (without angina pectoris). Ambulatory 24-h blood pressure measurement, but not office-based blood pressure measurement, was predictive for the occurrence of ST-segment depression. Risk factors for ST-segment depression were the Sokolow index > or =3.5 mV, smoking status, severity of coronary heart disease, use of diuretics, reduced left ventricular function, pulse pressure > or =60 mmHg and increase of double product (1,000 mmHg/min). A significant rise of the systolic/diastolic blood pressure (+8+ or -18/+7+ or -10 mmHg), of the heart rate (+12+ or -13/min) and of the double product (+2,471+ or -2,517 mmHg/min) was found during the transient ST depression as compared with the corresponding 24-h ambulatory blood pressure measurement mean values (P<0.0001 for all parameters specified). In most intermittent ST depressions, a rise of the double product was seen (n=789 episodes), and in the remaining 239 ST depressions, a fall of the double product was observed. ST depressions with fall of the double product showed a circadian distribution with a peak in the late evening. ST depression accompanied by a rise in double product showed two peaks (one in the early morning and one in the late evening). The prevalence of ST depression was significantly higher (28.6%) in extreme dippers than in dippers (18.2%), risers (21.8%) and non-dippers (19.6%). ST depressions have a high prevalence of 20.1% in hypertensive patients. Clinical predictors for the occurrence of ST-segment depression were classical risk factors and cardiac target organ damage. Office-based blood pressure measurement was not a useful measuring tool for forecasting the likelihood of ST-segment depression. ST depressions were triggered inter alia by variations of blood pressure and the heart rate. The circadian variability of the ST depressions is crucially affected by the pressure double product characteristics on which the ST depression is based.

Fifteen-year risk of major coronary events predicted by Holter ST-monitoring in asymptomatic middle-aged men

Ambulatory electrocardiogram monitoring (Holter) with ST-analysis as a measure of myocardial ischemia has in populations with coronary heart disease been shown to predict major coronary events: death, myocardial infarction or coronary revascularization. There has, however, been conflicting evidence regarding the usefulness of this technique in identification of healthy subjects with increased risk for coronary heart disease. The aim of this study was to assess if Holter monitoring with ST-analysis could be used to predict future major coronary events in asymptomatic middle-aged men with a defined aggregation of traditional risk factors for coronary heart disease. One hundred and fifty-five asymptomatic participants from the city of Malmö, Sweden, with known levels of conventional cardiovascular risk factors underwent Holter monitoring for analysis of transient ST-segment depression at the age of 55 years. Fifteen years after the Holter monitoring, hospital records, diagnosis and death registries were revisited for major coronary events. An ST-segment depression of 1 mm or greater (0.1 mV) was considered significant for myocardial ischemia and was found in 54 of the 155 men. There were no significant differences in risk factors in the two groups at baseline. The 15-year incidence of a first major coronary event was significantly higher in men with ST-segment depression (39%) than in men without ST-segment depression (20%) (P<0.015). A Holter electrocardiogram could predict future major coronary events with a positive and negative predictive value of 35 and 80%, respectively. Holter monitoring can be used as a complement to conventional risk factor evaluation in deciding whether or not to treat risk factors for CHD in asymptomatic subjects.

Increased soluble glycoprotein V concentration during the acute onset of unstable angina pectoris in association with chronic cigarette smoking

Platelet hyperactivity is important in the pathobiology of acute coronary syndromes. Glycoprotein V (GPV) is an integral membrane protein of platelets in the function of the GPIb-V-IX receptor for vWf/shear-dependent platelet adhesion in arteries. Soluble GPV is a novel marker of platelet activation. The aim of this study is to assess circulating soluble GPV levels in unstable angina pectoris (UA). Twenty-one patients (15 men, six women, aged 52 ± 7 years) with UA pectoris were studied. The inclusion criteria were angina at rest lasting >20 min during the preceding 6 h, with transient ST segment depression and/or T wave inversion and no evidence of myocardial infarction detected with the use of cardiac troponin-T. Coronary artery stenosis was angiographically confirmed in all patients. Twenty age- and sex-matched healthy adults (14 men, six women, aged 48 ± 7 years) served as controls. There were no significant differences among the studied groups with respect to age, sex, obesity, smoking, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride and platelet counts. Plasma-soluble GPV concentrations were higher in the UA patient group (126 ± 46 ng/ml) than those in the healthy controls (82 ± 15 ng/ml) (P = 0.001). There was a significant correlation only between plasma-soluble GPV levels and smoking (r = 0.526, P = 0.0001). Smoker UA patients had higher levels of soluble GPV than the non-smoker patients (139 ± 40 vs. 113 ± 50 ng/ml, respectively, P = 0.02). However, soluble GPV levels were similar in smoker and non-smoker healthy controls (P = 0.2). It is concluded that soluble GPV concentrations are significantly increased during the acute clinical course of unstable angina pectoris, indicating that soluble GPV may be useful marker of platelet activation in those patients. The level of the molecule is significantly affected from smoking in those patients.

ST-depression with negative T waves in leads V4-V5--a marker of severe coronary artery disease in non-ST elevation acute coronary syndrome: a prospective study of Angina at rest, with troponin, clinical, electrocardiographic, and angiographic correlation.

The significance of ST-segment depression in acute coronary syndrome has been the subject of debate for many decades. Studies indicate that different manifestations of ST/T changes may have significantly different prognostic implications. We studied the correlation of ST/T changes in 12-lead electrocardiography recorded during pain, to clinical and angiographic findings and in-hospital prognosis, in patients with non-ST-elevation acute coronary syndrome and elevated troponin levels. Fifty consecutive patients could be differentiated into two groups: (1) 25 patients with ST-segment depression and a negative T wave maximally in leads V4-5, (2) 25 patients with ST-segment depression and a positive T wave in the precordial lead with maximal ST-segment depression. Patients in group I had significantly more often left main or left main equivalent coronary artery disease; 76% versus 8% (P < 0.001), heart failure; 40% versus 4% (P = 0.005), and higher in-hospital mortality; 24% versus 0% (P = 0.02), than patients in group II. The troponin levels did not differ significantly between the groups. In patients with non-ST-elevation acute coronary syndrome and elevated troponin levels two subgroups could be identified. Transient ST-segment depression and a negative T wave maximally in leads V4-5 during anginal pain predicts left main, left main equivalent, or severe three-vessel coronary artery disease with high sensitivity and specificity. In patients with ST-segment depression and a positive T wave, there is a high probability of one-vessel disease.

Relationship between vascular dysfunction in peripheral arteries and ischemic episodes during daily life in patients with ischemic heart disease and hypercholesterolemia

Background It is well established that endothelial dysfunction is present in patients with ischemic heart disease and hypercholesterolemia. Some of these patients will have signs of transient myocardial ischemia during Holter monitoring. We sought to describe the correlation between daily life ischemia and signs of endothelial dysfunction as assessed by means of brachial vasoreactivity. Methods We included in the study 131 patients with documented ischemic heart disease and a serum cholesterol level of ≥5 mmol/L before the institution of lipid-lowering treatment and dietary intervention. Results Satisfactory 48-hour Holter recordings and ultrasound scans of the brachial artery were obtained in 119 patients. During 5712 hours of ambulatory monitoring, 181 episodes of transient ST-segment depression with a mean duration of 52 ± 66 minutes were recorded in 31 patients. The mean percentage dilatation of the brachial artery after occlusion was 4.38% ± 5.66%; after nitroglycerin administration, it was 13.86% ± 7.06%. By means of Spearman correlation analysis, the number of ischemic episodes and degree of flow-mediated vasodilatation and nitroglycerin-mediated vasodilatation were significantly negatively correlated (r = −0.249, P =.006 and r = −0.302, P =.02, respectively). In a linear regression model, the presence of ischemic episodes was a significant predictor of impaired flow-mediated vasodilatation (β = −3.31, P <.01), even after the adjustment for vessel size and classic cardiovascular risk factors. Conclusions These results indicate a significant relationship between ischemic episodes and vascular dysfunction in patients with ischemic heart disease and hypercholesterolemia and may justify an aggressive preventive therapy targeted directly at the endothelium. (Am Heart J 2002;144:108-14.)

Unusual ECG responses to exercise stress testing

We describe the case of a patient with coronary artery disease who developed transient ST-segment depression, right bundle branch block (RBBB), left anterior hemiblock, ST-segment elevation +ST), and “giant” T-waves in her electrocardiogram (ECG), an assortment of ECG patterns heretofore unreported in conjunction with exercise stress testing (EST). The amplitude of the +ST was modulated by the superimposed RBBB, as was shown by its augmentation after the abrupt disappearance of RBBB. Following recession of the latter “giant” T-waves, which usually are encountered in the hyperacute phase of myocardial infarction, developed and persisted late in the recovery period. Cardiac enzymes after EST were negative, and arteriography revealed a stenotic left anterior descending coronary artery. The present case indicates that a variety of ECG expressions of severe transmural ischemia or myocardial infarction can also be manifest in the course of EST; this also suggests a common pathophysiological mechanism in severe EST-triggered ischemia and the early phase of myocardial infarction.

Silent ST depression and cardiovascular end-organ damage in newly found, older hypertensives.

In hypertension, both reduced vascular supply and increased cardiac demand contribute to the development of (silent) myocardial ischemia. Our aim was to determine the prevalence of ST-segment depression and to analyze contributing factors in asymptomatic, previously untreated, older hypertensives. From a population survey, in 184 patients with mild hypertension (4 times systolic blood pressure >/=160 mm Hg and/or diastolic blood pressure >/=95 mm Hg), 60 to 75 years of age, cardiovascular end-organ damage was measured. Episodes of ST-segment depression were measured by 48-hour ambulatory Holter monitoring and were observed in 21 hypertensives (12%). They showed a significantly higher combined far-wall intima-media thickness of carotid and femoral arteries and more arterial plaques as measured by B-mode ultrasound compared with hypertensives without ST depression (0.00098+/-0.00021 versus 0.00088+/-0.00016 mm and 5.2+/-3.7 versus 3.7+/-2.8 plaques, P<0.05, respectively), whereas left ventricular mass index was not different (111+/-18 versus 104+/-24 g/m(2); P=0.18, respectively). In hypertensives with transient ST-segment depression, a significant relation was found between left ventricular mass and ischemic burden (r=0.51, P=0.02). Approximately 1 of 8 unselected and previously untreated older hypertensives show asymptomatic ST-segment depression, suggestive of silent myocardial ischemia. These data suggest that vascular factors mainly determine the occurrence of ischemic ST-segment depression and cardiac factors determine the ischemic burden in older hypertensives.

Improved long-term prognosis for patients with unstable coronary syndromes 1988-1995.

A more aggressive approach to unstable coronary syndromes has developed over the last decade. We set out to examine the long-term outcome among patients with acute coronary syndromes with respect to period of admission since 1988. 3918 patients with unstable angina or a non-Q wave myocardial infarction who were admitted to the coronary care unit at Ostra Hospital in the period 1988-1997 were included. Standardized criteria were used to define a non-Q wave myocardial infarction and included fulfilment of the following: (1) typical enzyme changes (serial serum aspartate aminotransferase above 0.7 microkat x l(-1), serial creatine kinase above 3.3 microkat x l(-1) or serial creatine kinaseMB subunit mass concentration above 15 microg x l(-1)), and at least one of the following: (2) chest pain, shock, syncope or pulmonary oedema suggestive of a myocardial infarction, (3) development of electrocardiographic changes with serial ST-T changes without Q waves. The standardized criteria for unstable angina pectoris were fulfilment of at least one of the following: (1) a clear worsening of a previous stable pattern of angina pectoris, (2) chest pain at rest or minimal effort with transient ST-segment elevation or depression on electrocardiogram or elevation of cardiac enzymes not reaching the criteria for myocardial infarction. Information on vital status and cause of death after discharge was collected from the national cause-specific mortality register. Two-year mortality decreased from 30% in 1988 to 19% in 1995 (relative risk per year 0.94 (0.90-0.97), 95% confidence interval). The improvement was consistent regardless of differences in age, prior myocardial infarction, diabetes mellitus, hypertension, development of non-Q wave myocardial infarction, treatment with heparin or thrombolytics or performance of acute coronary angiograms. The cumulative survival at 10 years was 53% in the unstable angina group and 36% in the non-Q wave myocardial infarction group (P<0.0001). Against a background of a more aggressive approach to acute coronary syndromes a decrease in long-term mortality is seen between 1988 and 1995.

NORMALIZATION OF HEMATOCRIT IN HEMODIALYSIS PATIENTS DOES NOT AFFECT SILENT ISCHEMIA

Transient ST-segment depression measured on ambulatory ECG monitors has been described as representing silent ischemia. Patients who demonstrate silent ischemia have been reported to show increased mortality compared to patients without silent ischemia. We undertook this study to determine if the correction of anemia in End Stage Renal Disease (ESRD) patients from(± = standard deviation) 30 ± 3 to 42 ± 3 with the use of Epoetin alfa would result in decreased silent ischemia in patients with clinically evident ischemic heart disease or congestive heart failure.Methods: Thirty one ESRD patients with congestive heart failure or patients with clinically-evident ischemic heart disease were randomized into one of two arms. Patients in Group A had their hematocrit increased with the use of slowly escalating doses of Epoetin alfa to 42 ± 3% and patients in Group B were maintained with a hematocrit of 30 ± 3% throughout the course of the study. All patients had a 24 hour Holter monitor recording at baseline and at 28 weeks after randomization (when they had reached their target hematocrit). Significant silent ischemia was considered to be present if patients demonstrated at least 60 seconds of ≥ 1 mm ST segment depression.Results: Fifteen patients were randomized to Group A and 16 patients were randomized to Group B. The mean hematocrit increased in group A from 29.1 ± 2.4% to 40.8 ± 5.2% after 30 weeks. The mean hematocrit in Group B remained stable at 30 ± 3% throughout the course of the study. Ten patients demonstrated silent ischemia at baseline. At follow up patients in group A demonstrated a mean of 1.7 ± 4.9 minutes of ischemia compared to 1.1 ± 3.4 minutes in group B. These were not significantly different. A similar number of patients in group A and Group B required adjustments in their anti-anginal medication during the course of the study.Conclusion: It is possible to increase hematocrit to near normal levels in hemodialysis with the administration of exogenous Epoetin alfa. The increase in hematocrit form 30 ± 3% to 42 ± 3% is not associated with a change in the level of silent ischemia these patients demonstrate.

ST-segment monitoring with continuous 12-lead ECG improves early risk stratification in patients with chest pain and ECG nondiagnostic of acute myocardial infarction

OBJECTIVESThe purpose of this study was to evaluate the prognostic importance of ischemic episodes detected by ST-segment monitoring with continuous 12-lead electrocardiography (ECG) in a nonselected coronary care unit (CCU) population with chest pain and ECG nondiagnostic of acute myocardial infarction (AMI).BACKGROUNDPatients with chest pain and ECG nondiagnostic of AMI constitute a heterogeneous group concerning both diagnosis and prognosis. Continuous 12-lead ECG is a rather new method not thoroughly studied in this population.METHODSThe ST-segment monitoring with continuous 12-lead ECG was performed for 12 h in 630 consecutive patients admitted to CCU due to chest pain and a nondiagnostic ECG, i.e., no ST-segment elevations. An ST-episode was defined as a transient ST-segment depression or elevation of at least 0.10 mV. The median follow-up time was six months.RESULTSA total of 176 ST-episodes occurred in 100 (15.9%) patients. The median duration and maximal ST-segment deviation in patients with ST-episodes were 80 min and 0.20 mV, respectively. Presence of ST-episodes predicted worse outcome concerning cardiac death and cardiac death or myocardial infarction (MI) (log-rank p < 0.001). At 30 day follow-up procedure, 10% versus 1.5% died from cardiac causes or had an MI in the group with and without ST-episodes, respectively. In a multivariate analysis, only troponin T ≥0.10 μg/l and the presence of ST-episodes came out as independent predictors of cardiac death or MI.CONCLUSIONSContinuous 12-lead ECG monitoring provides prognostic information on-line and considerably improves early risk stratification in patients with ECG nondiagnostic of AMI and symptoms suggestive of acute coronary syndrome.