A cardiac rhythmOften refers to a discernible pattern in time or distance between QRS complexes and/or P waves. that originates from 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... without the usual regular rhythm indicative of sinus rhythmAlso known as regular sinus rhythm or sinus rhythm, this cardiac rhythm is not a dysrhythmia; sinus rhythm originates in the sinoatrial (SA) node with a rate of 60-100/minute; P waves are upright in most leads and the QRS is...; this rhythm is common for children and for elderly adults; it presents as a narrowing of the R-R intervalThe distance between the top of the R waves. Figure 4.15 The Normal Q Wave and QT Interval Figure 4.15 illustrates the Q wave, QT interval and the R-R interval. A normal QT interval should be less than half the... during inspiration and a widening R-R intervalA period measured on rhythm strip paper that measures a wave and a segment; the distance measured is equal to time taken as an ECG is voltage over time; a PR interval for example is measured from the beginning of... during expiration; note that P wavesA wave generated from the depolarization of the atria; the P wave is upright when originating from the SA node. The P wave represents the depolarization of the right and left atria. The P wave begins with the first deviation... are upright in most leads and the QRSThe electrical representation of ventricular depolarization; the atrial repolarization is also a part of the QRS. ECG interpretation relies heavily on the QRS complex. The QRS complex represents the depolarization of the ventricles. The repolarization of the atria is also... is narrow (unless a Bundle Branch BlockSince the bundle branches are insulated – they are encapsulated with a fibrous sheath – an obstacle to conduction in any bundle (i.e. ischemia or infarct) results in the impulse not carried through to the ventricle; as a result, the... is coexisting).
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. 205