Ads
related to: multifocal atrial tachycardia images of blood flow
Search results
Results From The WOW.Com Content Network
Multifocal atrial tachycardia is characterized by an electrocardiogram (ECG) strip with three or more discrete P wave morphologies in the same lead, not including that originating from the sinoatrial node, plus tachycardia, which is a heart rate exceeding 100 beats per minute (although some suggest using a threshold of 90 beats per minute ...
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Donate
Atrial tachycardia is a type of heart rhythm problem in which the heart's electrical impulse comes from an ectopic pacemaker (that is, an abnormally located cardiac pacemaker) in the upper chambers of the heart, rather than from the sinoatrial node, the normal origin of the heart's electrical activity.
This is taken as evidence of multiple (i.e. at least two) ectopic foci, and is called multifocal (or more correctly, multiform) atrial rhythm if the rate is ≤100) or multifocal atrial tachycardia if the rate is over 100. [7] This appears particularly commonly in exacerbations of chronic obstructive lung disease. [8]
Without blood flow to the myocardium, it is deprived of oxygen, causing tissue death and irreversible damage. [5] The tissue destroyed by the infarction is replaced with non-functioning fibrosis, restoring some of the structural integrity of the organ but resulting in impaired myocardial function.
The body has several feedback mechanisms to maintain adequate blood flow and blood pressure. If blood pressure decreases, the heart beats faster in an attempt to raise it. This is called reflex tachycardia. This can happen in response to a decrease in blood volume (through dehydration or bleeding), or an unexpected change in blood flow.
Junctional rhythms can present with either bradycardia, a normal heart rate, or tachycardia. [9] The most obvious abnormal finding will be abnormal P waves. One of three options can occur: [12] 1. There are no P waves. This is because of either failure of retrograde flow to the atria or the P wave is hidden in the QRS.
Atrial tachycardia with complete A-V block and resulting junctional escape. Many conditions can cause third-degree heart block, but the most common cause is coronary ischemia. Progressive degeneration of the electrical conduction system of the heart can lead to third-degree heart block.