Chapters Archive – Page 14 of 22

Cardiac electrophysiology: action potentials and electrical vectors

Video lecture: Cardiac electrophysiology, action potentials, ECG leads & vectors

ECGs showing acute STEMI in two patients with severe chest pain. STEMI = ST elevation Myocardial Infarction.

STEMI (ST Elevation Myocardial Infarction): Diagnosis, ECG, Criteria, and Management

STEMI (ST Elevation Acute Myocardial Infarction): Epidemiology, Diagnosis (ECG), Criteria & Management Acute ST Elevation Myocardial Infarction (STEMI) is the most severe manifestation of coronary artery…

Figure 1. Exercise causes subendocardial ischemia and thus ST segment depression on the ECG.

Evaluation of exercise stress test: ECG, symptoms, blood pressure, heart rate, performance

Evaluation of the exercise stress test (exercise ECG) The ECG reaction has always been a central component of the exercise stress test. Indeed, clinicians often use…

Figure 1. The relationship between heart rate, stroke volume and cardiac output during exercise.

Exercise physiology: from normal response to myocardial ischemia & chest pain

Physiological principles of exercise stress testing, myocardial ischemia and ischemic symptoms Understanding the basic principles of exercise physiology is essential to conduct and evaluate the exercise stress…

Figure 1. Various T-wave abnormalities, including T-wave changes related to myocardial ischemia.

T-waves in ischemia: hyperacute, inverted (negative), Wellen’s sign & de Winter’s sign

T-wave changes in acute myocardial infarction & ischemia A thorough discussion regarding the physiology of the T-wave was previously provided. Only aspects relevant to ischemia…

Exercise stress testing in special patient populations

Exercise stress testing in patients with previous acute coronary syndromes (myocardial infarction), women, elderly and revascularized individuals Clinicians should be familiar with the special challenges…

Figure 2. This figure illustrates ST elevations, ST depressions and T-wave inversions. Patients with STEMI (STE-ACS) always display ST elevations but they may also display ST depressions and/or T-wave inversions. Patients with NSTE-ACS (NSTEMI, unstable angina), on the other hand, may only display ST depressions and/or T-wave inversions.

Clinical application of ECG in chest pain & acute myocardial infarction

Use of ECG in acute coronary syndromes & chest pain patients An ECG must be performed on all patients seeking medical attention due to chest discomfort…

Figure 1. Chest pain is the hallmark of myocardial ischemia. It signals that there is ongoing (acute) myocardial ischemia. Careful assessment of the symptoms is crucial to promptly establish a working diagnosis. Chest pain due to myocardial ischemia is rather characteristic, which means that the vast majority of patients with acute coronary syndromes can be treated before troponin test results have arrived. Hence, assessment of symptoms and ECG is sufficient to manage patients with chest pain.

Approach to patients with chest pain: differential diagnoses, management & ECG

Approach to patients with chest pain: differential diagnoses, evaluation and management Chest pain is one of the most common symptoms in the emergency department, as well…

Expected maximum heart rate according to age and sex.

Exercise stress test (exercise ECG): protocols, evaluation & termination

Exercise stress test (exercise ECG) protocols & equipment: cycle ergometer (bicycle) vs. treadmill The choice of exercise equipment and protocol depends mainly on local traditions. The…

Chronotropic incompetence (inability to increase heart rate)

Chronotropic incompetence: inability to adequately increase heart rate Chronotropic incompetence is an independent predictor of overall and cardiovascular mortality. The condition is very common among…