A rapid atrial rhythmOften refers to a discernible pattern in time or distance between QRS complexes and/or P waves. (approximately 300/minute in 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) caused by a re-entryOne of several causes of dysrhythmias, the re-entry loop often results in tachycardias; the re-entry loop requires an area with slowed speed of conduction, an proximal area with regular conduction speed and cells that are receptive to depolarizing; the loop... loop within the atria; since 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... is unable to conduct 300 impulses/ minute (max=240), the junction often allows every 2nd, 3rd, or 4th impulse through; resulting ventricular 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. is approximately 150, 100, and 75/min. respectively.
Atrial flutter occurs from a rapid conducting loop (reentrant) within the atria that fires at rates between 260-340 minute. Typically, though, the atria flutter at rates close to 300/minute. This rate is faster than the AV junction’s capacity (maximum is 240 impulses/minute). As a result, the AV junctionConducts the impulse through the fibrous plate that separates the atria and the ventricles; consists of the AV node and the bundle of His; functions also to slow the conduction speed to allow for atrial conduction prior to ventricular conduction... conducts only the 2nd, 3rd or 4th impulse to the ventricle, usually in a consistent patternPattern refers to the repeating components of an ECG rhythm in a predicative order. An ECG rhythm that is initiated by one of several intrinsic pacemaker sites of a heart will often generate a regular, even rhythm pattern. This can....
With only every 3rd or 4th impulse conducted, an abundance of 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 seen between the QRS complexes. These flutter (‘P’) waves resemble the teeth of a saw. Flutter waves are easily seen at these slower ventricular rates.
Since the atria flutter at rates of about 300/minute, a 2:1 conduction is the most common presentation of atrial flutter with ventricular rates of close to 150/minute. With 2:1 conduction, flutter waves do not usually appear (P waves are generally buried in either the QRS or 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...). For any supraventricular rhythmIf the QRS is narrow, the rhythm originates from a supraventricular site. Otherwise, if the QRS is wide, chances are, the rhythm is a ventricular rhythm. Remember that the ECG is a two dimensional plotting of voltage (height or amplitude)... with a rate close to 150/minute, consider atrial flutter.
If the patient is in atrial flutter, a vagal maneuverA maneuver that stimulates the Vagus nerve; possible maneuvers include a Valsalva maneuver (bearing down), ice thrust in ice water, anal stimulation, and carotid massage; baroreceptors in the carotid arteries respond to increased blood pressure (and increased cardiac output) by... can slow the AV nodeIs located in the inferior aspect of the right atria; functions to slow the conduction speed to allow for atrial conduction prior to ventricular conduction (atrial kick); also serves as a pacemaker if the SA node fails to fire. The..., effectively increasing the number of visible flutter waves.
If a patient is in supraventricularLocated above the ventricle – includes the bundle of His, AV node, atria and the SA node. 1. Six Second ECG Guidebook (2012), T Barill, p. 206 tachycardiaA cardiac rhythm with a rate above 100/minute; for example, if the impulse originates from the atria with a rate of 160/minute, the rhythm is called an atrial tachycardia. A cardiac rhythm is usually named first by the location of... with 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.... close to 150/minute, always consider the possibility that the rhythm is atrial flutter with a 2:1 block. Failure to detect this rhythm can lead to serious complications for those with Woolf-Parkinson-WhitePre-excitation syndrome characterized by the early depolarization of the ventricle(s) via an accessory pathway (other than the AV junction) resulting in an early initiation of a QRS and possibly a Delta wave; due to the presence of the accessory pathway,... syndrome or occasionally for those who have been in atrial flutter for more than 48 hours (risk of emboli).
Atrial flutter is often grouped with atrial fibrillationOne of the most common dysrhythmias, the atria have a host of sites that are concurrently firing at a combined rate of 350-600/minute; since the junction allows maximum 240 impulses through per minute, the result is a chaotic rhythm most.... Risk factors of atrial fibrillation can also apply to atrial flutter, though with less frequency. Atrial flutter also has a tendency to deteriorate into atrial fibrillation.
The 3 step process would probably take us to atrial flutter. The P waves are more indicative of an atrial locus. The appearance of more than one P wave between each QRS complexThe 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 a somewhat unique condition.
The simplest way to detect the number of flutter waves for every QRS complexA collection of waveforms (i.e. QRS complex and the ECG complex). 1. Six Second ECG Guidebook (2012), T Barill, p. 194 is to complete some simple math. Determine the ventricular rate. If the atria are fluttering at rates close to 300/minute, divide the ventricular rate into 300 and round off your answer. For example, if the ventricle rate is 100/minute with flutter waves, the atria flutters 3 times for every (300/100) ventricular depolarizationThe depolarization of the myocardium is represented on an ECG by a series of waveforms, one for atrial depolarization and soon after a larger waveform for ventricular depolarization. Normal ventricular depolarization begins with the septal fascicle of the left bundle.... You would call this rhythm atrial flutter with a 3:1 response.
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. 123-124, 191