Multifocal atrial tachycardia: Diagnosis, Causes, Pathofisiology, and treatment – Tachycardia is a condition in which the heart rate exceeds 100 beats/minute. Tachycardia can be categorized into two main types, namely supraventrikular or ventricular, where previously divided into narrow complex tachycardia and a wide complex tachycardia.
If the heart is beating too fast, the heart becomes less efficient at pumping blood, so blood flow throughout the body, including the heart itself, decreases. Because the heart beats faster, the heart muscle (myocardium) needs more oxygen; And if this situation continues,myocardial cells lacking oxygen can die, and cause a heart attack (myocardial infarction).
Multifocal atrial tachycardia (MAT) is an abnormal heart rhythm, specifically the type of supraventricular tachycardia, which is very common in the elderly and is associated with the exacerbation of chronic obstructive pulmonary disease (COPD).
Narrow complex Tachycardia diagnosis (QRS < 120 ms).
Sinus tachycardia.
There are many causes of sinus tachycardia in older people: pathological (anemia, thyrotoxicosis, hypoxemia, hypovolemia, hypotension), or physiological (anemia, fever). QRS complexes and normal P waves visible on EKG. Therapy by treating the underlying cause.
Atrial fibrillation.
Atrial fibrillation is an irregular rhythm along with ventricular contraction varied accompanied the absence of a clear P wave on the ECG. If there are disturbances of conduction from the Atria to the ventricles or the presence of bundle branch block before, it can be difficult to distinguish atrial fibrillation from atrial flutter because there is usually a change between fibrillation and flutter.
Atrial flutter.
At the heart, atrial flutter showed a “sawtooth” appearance of the P wave with a level of between 180 – 350 beats/minute. Atrial flutter associated with risk of atrial thromboembolism.
Paroxysmal supraventricular tachycardia (SVT).
Paroxysmal SVT is most often caused by re-entry of atrial impulses in the atrioventricular (AV) node. Wolff-Parkinson-White syndrome occurs when there is antegrade conduction through an accessory pathway, producing delta waves (rising after the QRS complex) and shortened PR intervals.
Multifocal atrial tachycardia (MAT).
MAT is an arrhythmia can occur in the case of heart failure or chronic obstructive pulmonary disease. MAT appears when there are three different P wave morphology that are not related to each other.
Read also: Symptoms of Ectopic heart beats.
Multifocal atrial tachycardia causes.
- MAT usually arise because of an underlying medical condition.
- Pulmonary Disease (COPD, hypertension, COR pulmonal).
- Hypersympathetic state (Increased catecholamine – Sepsis, Shock)
- Metabolic (Hypokalemia, Hypomagnesemia).
- The prevalence has been estimated around 3 per 1000 inpatients in older people hospitals and less frequently in pediatric practice;
- It is mostly in patients with disorders of the lungs, but can occur after acute myocardial infarction and can also occur on low blood potassium or low blood magnesium.
- It is sometimes associated with digitalis toxicity in patients with heart disease.
- It is most often associated with hypoxia and COPD.
- In addition, toxicity can be caused by Theophylline, a drug with a narrow therapeutic index is commonly used to treat COPD.
- Theophylline can cause a number of abnormal heart rhythms in excess, and thus further predispose COPD patients to MAT.
- Toxicity of Theophylline common in acute or chronic overtreatment.
Pathofisiology.
P wave and the P-R interval are varied due to a phenomenon called wandering atrial pacemaker (WAP).
Electrical impulses are generated on a different focus within the atrium of the heart.
WAP is positive when the heart produces at least three different P wave formations from the same ECG lead.
Then, if the heart rate exceeds 100 beats per minute, this phenomenon is called Multifocal atrial tachycardia.
Treatment of Multifocal atrial tachycardia.
Multifocal atrial tachycardia management mainly consists of treatment of the underlying cause.
But if it is assessed clinically as needed, the heart rate in some cases can be reduced by administering verapamil calcium channel blocker or beta blocker metoprolol.
Administering oxygen may play a role in the treatment of some patients.
