The inherent imperfection of clinical diagnostic tests introduces uncertainty into their interpretation. The magnitude of diagnostic uncertainty after any test result may be quantified by information theory. The information content of the electrocardiographic ST-segment response to exercise, relative to the diagnosis of angiographic coronary artery disease, was determined using literature-based...

Myocardial ischemia which occurs in the absence of chest pain or its equivalents (silent myocardial ischemia) is common in patients with coronary artery disease. Silent myocardial ischemia may also be found in asymptomatic patients, particularly those with underlying risk factors. It is important for physicians to identify the existence of silent myocardial ischemia because it is predictive of ...

The outcome of 50 consecutive modified predischarge exercise tests after acute myocardial infarction was predicted by three independent observers on the basis of ST segment displacement in the resting pretest 12 lead electrocardiograms. The mean predictive accuracy for the three observers was 82% for a positive test defined as additional ST segment depression or elevation greater than or equal ...

OBJECTIVES We examined the relationships between screen time (ST) and mental health problems and also increment of ST and progression of mental health problems in a college-based sample of Chinese youth. METHODS We assessed 2521 Chinese college freshmen from October 2013 to December 2014. At baseline, the mean age of participants was 18.43 years (SD 0.96 years), and 1215 (48.2%) participants ...

Compared with standard test criteria, simple heart rate (HR) adjustment of ST depression during exercise electrocardiography can improve the identification and assessment of underlying coronary artery disease. Since heart rate during exercise drives progressive ST segment depression in the presence of coronary obstruction that limits flow reserve, the ST/HR index controls for the increasing met...

Twenty four hour ambulatory monitoring was performed on 120 healthy volunteers using a frequency modulated recorder: 50 men and 50 women below 40 years and 20 men between 40 and 60 years were studied. Twenty eight subjects had episodes of ST segment elevation (range 1-3 mm), which occurred almost invariably at night with a slow heart rate 62.4 +/- 10.4 beats/min). ST segment elevation occurred ...

The electrocardiogram is notoriously unreliable for the diagnosis of ischaemic heart disease in patients with Wolff-Parkinson-White syndrome. Abnormalities in the resting tracing may lead to false positive diagnoses of inferior or anterior myocardial infarction. Although ST segment depression with exercise has been reported in patients with Wolff-Parkinson-White syndrome, the depth of depressio...

Hypothermia is known to cause specific electrocardiographic (EKG) changes such as Osborne waves and bradycardia. We report diffuse ST segment depression, an atypical EKG change, in a patient with a core temperature of 29.4°C (85°F). This patient had no previous cardiovascular pathology, and his EKG changes resolved gradually with aggressive warming. We also discuss the pathophysiology and clini...

BACKGROUND Several large, randomized clinical trials have shown that early thrombolytic therapy substantially reduces early mortality after acute myocardial infarction (MI). In most trials, eligibility criteria include typical chest pain and diagnostic ST segment elevation in two or more contiguous leads of the standard 12-lead ECG. Unfortunately, large areas of the thoracic surface are left un...