BACKGROUND Myocardial ischemia causes ST segment elevation or depression in electrocardiograms and epicardial leads. ST depression in epicardium overlying the ischemic zone indicates that the ischemia is nontransmural. However, nontransmural ischemia does not always cause ST depression. Especially in animal models, ST depression is hard to reproduce. OBJECTIVE The purpose of this study was to...

To ascertain whether exercise testing might predict multivessel coronary disease and left ventricular aneurysm after a myocardial infarction, 154 patients with a single documented myocardial infarction who had both exercise testing and coronary angiography were grouped according to whether they had greater than or equal to 1 mm ST depression, greater than or equal to 1 mm ST elevation, or neith...

Mechanism for ST Depression. Introduction: A mechanism is proposed for ST depression that arises on the epicardial surface above the border between normal and ischemic tissue. Depression is caused by current that flows in a transmural loop that begins and ends at the lateral boundary between healthy and ischemic tissue and that passes through the transmural boundary between healthy and ischemic...

To clarify the source of electrocardiographic ST depression associated with ischemia, a sheep model of subendocardial ischemia was developed in which simultaneous epicardial and endocardial ST potentials were mapped, and a computer model using the bidomain technique was developed to explain the results. To produce ischemia in different territories of the myocardium in the same animal, the left ...

OBJECTIVES We sought to investigate the short-term prognostic value of the admission electrocardiogram (ECG) in patients with a first acute myocardial infarction (MI) without ST segment elevation. BACKGROUND ST segment depression on hospital admission predicts a worse outcome in patients with a first acute MI, but the prognostic information provided by the location of ST segment depression re...

Near maximal graded exercise tests and coronary angiograms were compared in 37 patients with a history of chest pain and with ST segment depression at rest, who were free of obvious nonischemic causes of ST depression. Additional ST depression of 0.1 mV or more occurred with exercise in 26 patients and 23 of these had obstruction of one or more coronary arteries (sensitivity = 0.92). Eleven pat...

BACKGROUND Reciprocal changes may accompany ST segment elevation in the ischemic territory during acute myocardial infarction (AMI). We examined the hypothesis that isolated inferior ST segment depression on admission is an early sign of anterior wall infarction. METHODS 49 patients admitted to the coronary care unit between January 1996 and June 2008 who presented with inferior ST segment de...

ST-segment depression is commonly seen in patients with acute coronary syndromes. Most authors have attributed it to transient reductions in coronary blood flow due to nonocclusive thrombus formation on a disrupted atherosclerotic plaque and dynamic focal vasospasm at the site of coronary artery stenosis. However, ST-segment depression was never reproduced in classic animal models of coronary s...

P atients with non-ST segment elevation acute coronary syndrome (NSTE-ACS) are heterogeneous with regard to both underlying disease and prognosis. ST segment depression on admission in NSTE-ACS is considered a powerful predictor of a poor outcome. To clarify the clinical significance of ST segment depression, we studied the relation between the change in ST segment depression after admission, t...

OBJECTIVES The aim of this study is to demonstrate the effect of resting ST segment depression on the diagnostic characteristics of the exercise treadmill test. BACKGROUND Previous studies evaluating the effect of resting ST segment depression on the diagnostic characteristics of exercise treadmill test have been conducted on relatively small patient groups and based only on visual electrocar...