More accurately called synchronous cardioversion, an electrical current is applied to the heart when the ventriclesThe larger chambers of the heart (3 times the volume and muscle thickness than the atria), responsible for the pumping of blood to the lungs and the rest of the body. are depolarizing (R waveFollowing the depolarization of the interventricular septum, ventricular depolarization then progresses from the endocardium through to the epicardium across both ventricles producing an R wave and an S wave. An R wave is the first positive deflection of the QRS... as opposed to firing on the T waveThe wave that arrives after the QRS; is a graphical presentation of ventricular repolarization. Expect a T wave to follow every QRS complex. The T wave is a graphic representation of the repolarization of the ventricle. The T wave is... which could produce lethal dysrhythmiasUsed interchangeably with arrhythmia, refers to any abnormal rhythm – not normal sinus rhythm or sinus tachycardia. 1. Six Second ECG Guidebook (2012), T Barill, p. 196 – R-on-T phenomena) to produce a period of asystoleAbsence of electrical activity demonstrated by a straight ECG line. Most students of dysrhythmia courses arrive with the claim that they are at least skilled in recognizing asystole. In fact, most of us have seen the proverbial straight line on... with the objective of allowing the SA nodeThe SA node, usually the dominant pacemaker, is located in the right atrium at the opening of the superior vena cava. The SA (sinoatrial) node is a clump of hundreds of specialized cardiac cells that have the ability to self-initiate... to become the pacemakerAn electronic pulse generator that stimulates depolarization of the atria and/or the ventricles. 1. Six Second ECG Guidebook (2012), T Barill, p. 201.
1. Six Second ECG GuidebookA Practice Guide to Basic and 12 Lead ECG Interpretation, written by Tracy Barill, 2012 Introduction The ability to correctly interpret an electrocardiogram (ECG), be it a simple six second strip or a 12 lead ECG, is a vital skill... (2012), T Barill, p. 193