Also referred to as multiformed atrial rhythmOften refers to a discernible pattern in time or distance between QRS complexes and/or P waves., is a dysrhythmiaUsed 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 with at least 3 different 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... originating 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..., 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 and/or 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....
Various events cause increased automaticityA cardiac cell’s (usually pacemaker cells such as the SA node, AV node or His-Purkinje network) ability to self-initiate an impulse; note that abundant catecholamines and/or ischemia enhances automaticity – non-pacemaker cells may become pacemaker cells. The SA node, usually... throughout the atria which may lead to a phenomenon whereby several atrial foci compete for dominance. Called a multifocal atrial rhythm or wandering pacemakerAn electronic pulse generator that stimulates depolarization of the atria and/or the ventricles. 1. Six Second ECG Guidebook (2012), T Barill, p. 201, the ‘P’ waves can come from the SA node, 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... and anywhere in the atria. Three different P wave morphologies (shapes) are necessary to call this a multiformed atrial rhythm. If the rhythm is a 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..., it is called multifocal atrial tachycardia (MAT)Often associated with atrial hypertrophy, pulmonary hypertension and COPD, MAT is a tachycardia diagnosed by the presence of 3 or more P waves of differing morphologies. Various events cause increased automaticity throughout the atria which may lead to a phenomenon....
A multifocal atrial rhythm is often an irregular rhythm. For MAT with rates greater than 140/minute, ‘P’ waves are difficult to differentiate from T waves. Rapid 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... may look quite similar to rapid MAT. Note: 3 different ‘P’ wave shapes are necessary to call tachycardias MAT.
Multifocal atrial rhythm occurs with conditions such as chronic obstructive pulmonary disease (COPDChronic obstructive pulmonary disease (COPD) is a group of respiratory diseases that involve structural changes to the lung tissue that impair gas exchange (oxygen and carbon dioxide exchange). Emphysema and chronic bronchitis are two of the most common conditions. Table...), digitalis toxicity and atrial hypertrophy (commonly related to pulmonary hypertensionBlood pressure above acceptable limits – above 90 mm of Hg diastolic and above 140 mm of Hg systolic. 1. Six Second ECG Guidebook (2012), T Barill, p. 167, 197 associated with COPD).
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. 125, 208