A heart rateThe number of QRS complexes per minute; note that HR may not equal perfused pulse rate. See also: - Step 1 Heart Rate - Rate - Rule of 300s (Triplicate Method) - Six Second Count - The Caliper Method 1.... slower than a pacemaker’s regular intrinsicCharacteristic or property natural to the heart and its structures. 1. Six Second ECG Guidebook (2012), T Barill, p. 198 rateHeart Rate; calculated by counting the number of QRS complexes in six seconds and multiplying by 10; rate is also determined by measuring the number of large squares between two R waves; i.e. –1 large square = heart rate of 300/minute. – commonly thought as less than 60/minute for sinus rhythms; less than 40/minute for junctional rhythmsA cardiac rhythm that occurs as a backup pacemaker when the sinus node fails to initiate an impulse; the junction typically fires at 40-60/minute; the P wave is either absent or inverted. A cardiac rhythm is usually named first by....
The term ‘bradycardia’ describes a heart rate less than the normal rate expected of the originating impulse site. For example, a rate less than 60/minute is a bradycardia for 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... and the atriaRight and left atria (1/3 volume and muscle mass of the ventricles) pump blood to the ventricles. Chambers and Layers of the Heart 1. Six Second ECG Guidebook (2012), T Barill, p. 190. For rhythms originating from the junctionConnects the atria to the ventricle and slows the impulse conduction speed sufficiently to allow for atrial kick; the junction consists of the AV node and the bundle of His; the junction is a supraventricular structure. 1. Six Second ECG... which normally delivers impulses at 40-60/minute, a junctional bradycardiaA cardiac rhythm that occurs as a backup pacemaker when the sinus node fails to initiate an impulse; the junction typically fires at 40-60/minute; the P wave is either absent or inverted. When the heart rate drops below 40/minute then... is less than 40/minute. Ventricular bradycardia (less than 20/minute) is also called an agonal rhythmA fatal dysrhythmia with rates usually less than 20/minute and common widening of the QRS; also referred to as the dying heart. Asystole is characterized by the absence of any waveforms. In reality, asystole is seldom a bone straight line... for it is only rarely associated with a pulse.
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. 119, 192