Chapters Archive – Page 20 of 22

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.

Myocardial Ischemia & infarction: Cellular changes, ECG and symptoms

Myocardial ischemia: cellular changes, ECG signs and development of infarction Like all other cells in the human body, cardiac myocytes use ATP (adenosine triphosphate) as…

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.

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

Classification, diagnosis and definitions of acute coronary syndromes (ACS) and acute myocardial infarction (AMI) Acute coronary syndromes occur when atherosclerotic plaques disrupt, resulting in the…

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

Introduction to Coronary Artery Disease (Ischemic Heart Disease)

Coronary artery disease (ischemic heart disease) Coronary artery disease, which is synonymous with ischemic heart disease, is the most common form of cardiovascular disease. It…

Figure 1. Overview of tachyarrhythmia (tachycardia).

Diagnosis and management of supraventricular and ventricular tachyarrhythmias: Narrow complex tachycardia & wide complex tachycardia

Diagnosis and management of narrow and wide complex tachycardia All clinically significant supraventricular and ventricular tachyarrhythmias have been reviewed in previous sections. However, given that…

Pacemaker-mediated tachycardia (PMT): ECG and management

Pacemaker-mediated tachycardia (PMT) Pacemaker-mediated tachycardia may arise if the pacemaker records a rapid atrial rate (e.g. during a supraventricular tachycardia) and stimulates the ventricles with…

Figure 1. Ventricular fibrillation and asystole.

Ventricular fibrillation, pulseless electrical activity and sudden cardiac arrest

Ventricular fibrillation, pulseless electrical activity (PEA) and sudden cardiac arrest This chapter will focus on ventricular fibrillation and pulseless electrical activity (PEA). These are highly lethal…

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)

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

The QT interval, long QT syndrome (LQTS) & ventricular arrhythmias (torsade de pointes) due to prolonged QT interval The QT interval is the time interval…

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

Ventricular tachycardia (VT): types, causes, ECG features and management This chapter deals with ventricular tachycardia from a clinical perspective, with emphasis on ECG diagnosis, definitions, management,…

Ventricular rhythm and accelerated ventricular rhythm (idioventricular rhythm)

Ventricular rhythm and accelerated ventricular rhythm (idioventricular rhythm) This article provides an overview of ventricular rhythm and accelerated ventricular rhythm, the latter also known as…

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

Junctional rhythm (escape rhythm) and junctional tachycardia

Rhythms arising near the atrioventricular node: junctional rhythm (escape rhythm) and junctional tachycardia In this article, you will learn about rhythms arising in, or near,…