General Cardiology

Figure 1. Posterolateral (posterior, inferobasal) transmural ischemia causes reciprocal ST-segment depressions in V1–V3 (ocasionally V4). Leads V7–V9 must be placed to reveal the ST-segment elevations.

ECG

ST elevation myocardial infarction (STEMI) without ST elevations on 12-lead ECG

ST elevation myocardial infarction (STEMI) without ST segment elevations on

Figure 1. Types of ST segment elevations on ECG.

ECG

ST segment elevation in acute myocardial ischemia and differential diagnoses

ST segment elevation in acute myocardial ischemia ST segment elevations

Figure 1. Characteristics of ischemic ST segment depressions on ECG.

ECG

ST segment depression in myocardial ischemia and differential diagnoses

ST segment depression due to acute myocardial ischemia ST segment

Figure 1. (A) The relation between the action potential and the ECG curve. Myocardial ischemia primarily affects the repolarization, which is reflected on ST-T changes on the ECG. (B) Note that the reference level for measuring deviation (elevation or depression) of the ST segment is the PR segment (the terminal portion of the PR interval). (C) and (D) Shows how to measure the magnitude of ST segment elevation and ST segment depression. The J 60 point is located 60 ms after the J point.

ECG

ECG in myocardial ischemia: ischemic changes in the ST segment & T-wave

ECG in acute myocardial ischemia: ischemic ST segment & T-wave

Figure 3. STE-ACS (STEMI) is caused by a complete occlusion, which means that there is no flow in the artery. The ischemia will affect all layers of the myocardium, from the endocardium to the epicardium (in the region supplied by the occluded artery). This type of ischemia, which affects all myocardial layers, is referred to as transmural ischemia.

ECG

Factors that modify the natural course in acute myocardial infarction (AMI)

Factors that modify infarct size and the natural course in

The right ventricle is supplied by the right marginal artery (r. marginalis dx), which originates from the right coronary artery (RCA). The RCA also supplies the inferior left ventricular wall in over 90% of all individuals. Hence, a proximal occlusion (in the RCA) which cuts off blood flow to the right ventricle, will also affect the inferior wall of the left ventricle in 90% of the cases.

ECG

The left ventricle in myocardial ischemia and infarction

Acute myocardial infarction (AMI) always affects the left ventricle Myocardial

Figure 1. Myocardial cells require continues oxygen supply in order to maintain normal metabolism. If oxygen supply is less than oxygen demand, ischemia developes. Myocardial cells can switch to anaerobic metabolism and discontinue contractions in order to alleviate the ischemia. This enables the cell to endure up to 30 minutes of severe ischemia. If blood flow is not restored before 30 minutes, the cell will die. Death of myocardial cells is referred to as myocardial infarction.

ECG

Myocardial Ischemia & infarction: Reactions, ECG Changes & Symptoms

Myocardial ischemia: reactions, ECG and development of infarction As all

Cardiac troponin I (TnI) and T (TnT): Interpretation and evaluation in acute coronary syndromes

Troponin is a protein complex expressed in cardiac and skeletal

Figure 1. Acute myocardial infarction is usually initiated by rupture or erosion of a vulnerable (unstable) atherosclerotic coronary plaque.

ECG

Diagnostic Criteria for Acute Myocardial Infarction: Cardiac troponins, ECG & Symptoms

Acute Myocardial Infarction: Definition & Criteria Acute myocardial infarction is

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.

ECG

Clinical application of ECG in chest pain & acute myocardial infarction

Use of ECG in acute coronary syndromes & chest pain

Figure 1. Flow-chart showing the natural course of coronary artery disease and classification of acute coronary syndromes into STEMI, NSTEMI and unstable angina using ECG criteria.

ECG

Classification of Acute Coronary Syndromes (ACS) & Acute Myocardial Infarction (AMI)

Classification, diagnosis and definitions of acute coronary syndromes (ACS) and

Figure 1. Atherosclerotic plaque which has ruptured and lead to atherothrombosis.

ECG

Introduction to Coronary Artery Disease (Ischemic Heart Disease) & Use of ECG

Coronary artery disease (ischemic heart disease) Coronary artery disease, which

12-lead ECG (presented according to Cabrera), recorded at 63 years of age, demonstrates concave-upward ST-segment depression in leads I, II, aVL, aVF, and V2 through V6; and ST-segment elevation in lead aVR (which corresponds to an identical ST-segment depression in the inverted lead -aVR). A notch is evident in the ascending part of the ST segment.

Information

A Novel Familial Cardiac Arrhythmia Syndrome Identified Using ECG

A novel potentially life-threatening cardiac arrhythmia syndrome identified with ECG

Figure 38. The electrical axis of the heart (heart axis).

Information

The electrical axis of the heart (heart axis): ECG & physiology

The electrical axis of the heart (heart axis) Although often

Figure 18. Normal and pathological T-waves.

Information

The T-wave: physiology, variants and ECG features

The normal T-wave Assessment of the T-wave represents a difficult

Figure 14. Example of measuring ST deviation (elevation and depression).

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The ST segment: physiology, normal appearance, ST depression & ST elevation

The ST segment: physiology, normal appearance, ST depression & ST

Bazett's formula for calculating corrected QT duration (QTc).

Information

QT duration & corrected QT (QTc) duration: ECG features & implications

QT duration and corrected QT (QTc) duration ECG interpretation always includes

Figure 2. P-wave morphology in chest and limb leads.

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P-wave, PR interval, PR segment: physiology, criteria & ECG findings

Physiology and ECG features of the P-wave, PR interval and

Information

The QRS complex: ECG features of the Q-wave, R-wave, S-wave & duration

The QRS complex (ventricular complex): normal and abnormal configurations and

Information

Overview of the ECG Waves, Deflections, Intervals, Durations

Video lecture: The ECG curve: P-wave, PR Interval, Q-wave, R-wave,

ECG

Approach to ECG Interpretation, Assessment of Rhythm and the P-wave

Video lecture: Assessment of rhythm & P-wave

ECG

The PR Interval & PR segment

Video lecture: The PR interval & PR segment This video

ECG

The QRS Complex: Q-wave, R-wave, S-wave, R-wave progression

Video lecture: The QRS complex: Q-wave, R-wave & S-wave

ECG

The Electrical Axis of the Heart

Video lecture: Assessment of the electrical axis of the heart

The ST segment: J-point, J-60 point, ST depression, ST elevation

Video lecture: The ST segment: J point, J 60 point,

ECG

The T-wave: T-wave inversions, hyperacute T-waves, large T-waves, flat T-waves

Video lecture: The T-wave: normal, inverted (negative) hyperacute and flat

ECG

The QT and QTc Interval

Video lecture: Assessment of the QT interval (QTc interval)

ECG

Basic Cardiac Anatomy (Anatomy of the Heart)

Video lecture: Cardiac Anatomy

ECG

Introduction to Electrocardiology and ECG Interpretation

Video lecture: Introduction to ECG interpretation

ECG

Cardiac electrophysiology: action potentials and electrical vectors

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

Information

CME: How dietary fat affects coronary arteries, LDL cholesterol and body weight

Coronary artery disease: On LDL cholesterol, dietary fat & statins

Figure 1. Cross-sectional view of ventricular wall thickness in children (

Information

Introduction to pediatric & neonatal ECG interpretation

Principles of pediatric & neonatal ECG interpretation Pediatric and neonatal

Figure 1. Overview of tachyarrhythmia (tachycardia).

Arrhythmology

Diagnosis and management of narrow and wide complex tachycardia

Diagnosis and management of supraventricular and ventricular tachyarrhythmias: Narrow complex

Arrhythmology

Pacemaker mediated tachycardia (PMT): ECG and management

Pacemaker mediated tachycardia (PMT) Pacemaker mediated tachycardia may arise if

ECG showing an episode of sinus rhythm (with multiple ventricular premature beats) spontaneously converting to Torsade de Pointes ventricular tachycardia. Notice how arterial blood pressure (ABP) drops at the onset of TdP. ECG by Nakstad et al (Scand J Trauma Resusc Emerg Med. 2010; 18: 7)

Arrhythmology

Long QT (QTc) interval, long QT syndrome (LQTS) & torsades de pointes

The QT interval, long QT syndrome (LQTS) & ventricular arrhythmias

Figure 1. Ventricular fibrillation and asystole.

Arrhythmology

Ventricular fibrillation, pulseless electrical activity and sudden cardiac arrest

Ventricular fibrillation, pulseless electrical activity (PEA) and sudden cardiac arrest

Arrhythmology

Ventricular tachycardia (VT): ECG criteria, causes, classification, treatment

Ventricular tachycardia (VT): types, causes, ECG features and management This chapter

Arrhythmology

Ventricular rhythm and accelerated ventricular rhythm (idioventricular rhythm)

Ventricular rhythm and accelerated ventricular rhythm (idioventricular rhythm) In this

Figure 1. Two types of junctional (escape) rhythm.

Arrhythmology

Junctional rhythm (escape rhythm) and junctional tachycardia

Rhythms arising near the atrioventricular node: junctional rhythm (escape rhythm)

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