Multifocal Atrial Tachycardia: Symptoms, Causes and Treatment
Updated: 2 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026
Quick Answer: What is multifocal atrial tachycardia?
Multifocal atrial tachycardia is a fast, irregular heart rhythm triggered by multiple abnormal electrical signals in the atria, with a rate above 100 beats per minute. It is strongly linked with lung disease, especially COPD. Most people have no symptoms from the rhythm itself. An ECG identifies it, and treatment usually focuses on the underlying cause.
What the research says
MAT is usually a secondary rhythm found in seriously ill, often older, people. A review in Chest describes MAT as typically seen in elderly patients with severe illnesses, most commonly COPD. It advises supportive measures and aggressive reversal of the precipitating causes first, notes that the role of antiarrhythmic drugs is unclear because MAT is commonly secondary, and says metoprolol, magnesium and verapamil have been evaluated in a few treatment studies (McCord & Borzak, Chest, 1998). [3]
COPD is linked with several heart-rhythm problems, MAT among them. A review of electrocardiographic abnormalities in COPD lists premature beats, atrial fibrillation, atrial flutter, MAT and ventricular tachycardia, and concludes that identifying ECG abnormalities and assessing arrhythmic risk may affect management and outcomes (Goudis et al., Int J Cardiol, 2015). [4]
An ECG definition is central to diagnosis, and delayed diagnosis can matter. In a review of pediatric MAT, the rhythm is defined by irregular P-P, R-R and P-R intervals, an isoelectric baseline between P waves and a ventricular rate above 100 beats per minute. Most children have a favorable outlook, but adverse outcomes were reported (cardiogenic death 3%, respiratory failure 6%, persistent arrhythmia 7%) in cases of delayed diagnosis and poorly controlled MAT (Chen et al., Front Pediatr, 2022). [5]
Multifocal atrial tachycardia (MAT) is a fast, irregular heart rhythm caused by multiple abnormal electrical signals in the atria, the heart’s upper chambers. The heart rate is above 100 beats per minute and can reach 150 beats per minute.
MAT is often associated with lung disease, especially chronic obstructive pulmonary disease. It can also occur with respiratory failure, infection, heart disease, electrolyte problems, cancer, diabetes, major surgery or kidney failure.
Many people do not notice symptoms. When symptoms occur, they may include palpitations, chest pain, shortness of breath or fainting. MAT is usually found on an electrocardiogram (ECG or EKG), and treatment generally focuses on the condition that caused the rhythm problem.
How does the heart’s rhythm become fast and irregular?
The heart’s atria normally receive and coordinate electrical signals that help the chambers contract. In MAT, several abnormal signals arise in the atria instead of one organized rhythm.
These signals make the heartbeat fast and irregular. When the heart pumps too often, it has less time to fill its chambers with blood. Each heartbeat may move a smaller amount of blood to the body’s cells.
MAT is a rhythm finding, not a complete explanation of why the heart is behaving that way. The underlying illness is an important part of diagnosis and treatment.
How is multifocal atrial tachycardia different from atrial fibrillation and flutter?
MAT and atrial fibrillation are both abnormal rhythms involving the heart’s upper chambers. They can be confused, and some people receive an atrial-fibrillation diagnosis when the rhythm is actually MAT.
A provider can tell the difference by reviewing an ECG and looking at the P waves, which show when the atria contract.
About half of people with MAT develop atrial fibrillation or atrial flutter. That is one reason follow-up for the underlying condition and heart rhythm can matter.
Rhythm | Key features |
Multifocal atrial tachycardia | Multiple abnormal atrial signals create a fast, irregular rhythm; P-wave patterns on ECG help identify it. |
Atrial fibrillation | Another abnormal upper-chamber rhythm that can be confused with MAT; ECG review distinguishes the patterns. |
Atrial flutter | An abnormal upper-chamber rhythm that may develop in people who have MAT. |
Only a qualified clinician interpreting the ECG can determine which rhythm is present.
What are the symptoms of MAT?
Most people do not have symptoms of MAT. They may instead notice symptoms caused by the underlying lung, heart or other medical condition.
When symptoms occur, they may include:
Chest pain.
Palpitations, such as a racing or fluttering heartbeat.
Shortness of breath.
Fainting.
Chest pain, severe shortness of breath or fainting can be signs of a serious problem. Seek urgent medical care rather than trying to identify the rhythm at home.
Symptom | What to do |
Palpitations | Tell a healthcare provider, especially if new, persistent or accompanied by weakness or breathlessness. |
Chest pain | Seek urgent medical evaluation. |
Shortness of breath | Seek urgent care if severe, sudden or worsening. |
Fainting | Seek urgent medical evaluation, particularly if it occurs with chest pain or breathing difficulty. |
No symptoms | MAT may still be found on an ECG during evaluation of another condition. Follow the recommended follow-up plan. |
What causes multifocal atrial tachycardia?
MAT most commonly occurs with lung disease. About 60% to 85% of people with MAT have lung disease, and chronic obstructive pulmonary disease is the most common associated issue.
Other causes include:
Associated condition | Context |
Respiratory failure | MAT may be identified while a person is hospitalized for serious breathing problems. |
Infection | An infection can contribute to the stress associated with the rhythm. |
Coronary artery disease | Reduced blood flow to heart muscle can be associated with MAT. |
Heart failure | The strain of heart failure may accompany the rhythm problem. |
Low potassium, magnesium or sodium | Electrolyte changes can contribute to abnormal rhythms. |
Cancer | Cancer is listed among conditions associated with MAT. |
Diabetes | Diabetes is another possible association. |
Major surgery | Physiologic stress around major surgery may be associated with MAT. |
Kidney failure | Kidney failure can occur alongside the rhythm. |
Pulmonary embolism | A rare association. |
Heart valve disease | A rare association. |
An association does not prove that one condition caused MAT in a particular person. The medical team must evaluate the full clinical picture.
How is MAT diagnosed?
Healthcare providers usually discover MAT on an electrocardiogram, also called an ECG or EKG. The ECG records the heart’s electrical activity.
The ECG is the only test a provider needs to make a MAT diagnosis. The provider examines the rhythm and the P waves that show when the atria contract. This helps distinguish MAT from atrial fibrillation and other abnormal rhythms.
After identifying MAT, a provider may order tests to evaluate the underlying condition:
A chest X-ray.
Blood tests.
An echocardiogram in rare situations.
The tests depend on symptoms, medical history and the suspected cause.
What does an ECG show in MAT?
An ECG can show the fast and irregular rhythm associated with MAT. Providers look at the atrial signals and P waves to understand whether multiple atrial sites are producing the rhythm.
An infographic or online rhythm strip cannot diagnose a reader. ECG interpretation should be performed by a qualified healthcare professional who can connect the tracing with symptoms, medications, oxygen levels, blood tests and the underlying illness.
How is MAT treated?
Many people need treatment for the condition that caused MAT rather than a separate procedure for the rhythm. MAT often goes away when the underlying cause is treated.
A person with MAT may already be in the hospital, especially when respiratory failure or another serious illness is involved. Treatment may include care for the lung, heart, infection, electrolyte or other condition contributing to the rhythm.
Medicines and electrolyte replacement
Depending on the situation, treatment may include:
Beta-blockers, such as metoprolol.
Magnesium and potassium when replacement is needed.
Calcium channel blockers, such as verapamil or diltiazem.
Medication choice depends on the underlying condition and overall health. Do not start, stop or change a heart medicine without clinician guidance.
Rare procedure-based treatment
Rarely, a person with MAT may need AV node ablation and a pacemaker. This is not routine treatment for every person with MAT. A specialist decides whether it is appropriate after evaluating the rhythm, underlying illness and response to other care.
What are treatment side effects?
Medicines for multifocal atrial tachycardia (MAT) may cause side effects such as dizziness, headache, upset stomach, diarrhea and constipation.
Dizziness.
Headache.
Upset stomach.
Diarrhea.
Constipation.
Ask the prescribing clinician which side effects should be reported promptly. Do not assume that a new symptom is a medication side effect; chest pain, fainting and severe breathing difficulty require urgent evaluation.
How long does MAT last?
MAT usually goes away once the condition causing it is treated. The time course depends on the underlying illness and how it responds to care.
Some people need a beta-blocker or calcium channel blocker for a while. About 25% of people with MAT need one of these medicines for a period of time.
People may be able to leave the hospital after successful treatment of the condition that caused the rhythm. Long-term follow-up may be needed when the underlying heart or lung condition is chronic.
What is the outlook for MAT?
Prognosis depends on the condition that caused MAT. The rhythm itself is not the only factor that determines outcome.
Studies describe a 30% to 60% in-hospital death rate among people with MAT and explains that the conditions causing the tachycardia—not the abnormal rhythm itself—can be fatal. This is a broad population-level statistic from a medically complex group and cannot predict an individual outcome.
The most useful question is not “What is the MAT survival rate?” but “What caused this rhythm, how serious is that condition and how is it responding to treatment?” Ask the treating team to explain what the ECG and underlying diagnosis mean for you.
Can MAT be prevented?
Keeping heart or lung conditions from getting worse may reduce the risk of MAT. Prevention therefore focuses on following the care plan for chronic lung or heart disease and attending recommended follow-up visits.
If you have a long-term condition, regular appointments can help your healthcare team monitor whether it is under control. Do not change oxygen, inhalers, heart medicines or other treatments without asking the clinician managing the condition.
How do you live with or follow up after multifocal atrial tachycardia?
Follow-up focuses on the condition that caused the rhythm. A clinician may review symptoms, medication needs, breathing or heart function and whether the underlying problem is controlled.
Ask how long you need to take a prescribed medicine and what symptoms require a call. If you are unsure whether palpitations, chest discomfort, faintness or breathlessness are expected, contact your care team.
Questions to ask at a visit
What caused my multifocal atrial tachycardia?
How did the ECG show MAT rather than atrial fibrillation or atrial flutter?
Do I have a lung, heart, infection, electrolyte or other condition contributing to the rhythm?
What tests do I need after the ECG?
How long do I need to take the medicine prescribed for me?
What side effects should I report?
What is the outlook for my specific underlying condition?
Could I have MAT again?
What symptoms should prompt emergency care?
How often do I need follow-up?
When should I seek urgent care?
Seek urgent medical attention for chest pain, fainting, severe or worsening shortness of breath, or other symptoms of serious illness.
A fast, irregular rhythm may be found in someone who is already seriously ill. Do not try to diagnose MAT from a smartwatch, pulse check or online ECG image. Emergency professionals can assess the rhythm and the underlying cause.
Conclusion: Treat the cause and follow the rhythm
Multifocal atrial tachycardia is a fast, irregular rhythm created by multiple abnormal signals in the atria. Many people have no symptoms, while others experience palpitations, chest pain, shortness of breath or fainting.
MAT is strongly associated with lung disease, especially chronic obstructive pulmonary disease, but it can also occur with respiratory failure, infection, heart disease, electrolyte changes, cancer, diabetes, major surgery or kidney failure.
An ECG is the key diagnostic test. Providers examine the P waves to distinguish MAT from atrial fibrillation and other upper-chamber rhythms. Treatment usually focuses on the condition that caused MAT, with clinician-guided medicines or electrolyte replacement when needed and rare procedure-based treatment in selected cases.
MAT often improves when the underlying condition is treated. Prognosis depends mainly on that condition, so population statistics should not be used to predict one person’s outcome.
If you have chest pain, fainting, severe shortness of breath or a new racing or irregular heartbeat, seek medical care promptly and ask the care team what is causing the rhythm.
Frequently Asked Questions
What is multifocal atrial tachycardia?
Multifocal atrial tachycardia is a fast, irregular rhythm caused by multiple abnormal electrical signals from the heart’s upper chambers. The heart rate is above 100 beats per minute and can reach 150 beats per minute.
What is another name for MAT?
MAT is also called chaotic atrial tachycardia.
Is multifocal atrial tachycardia dangerous?
MAT can occur with serious lung, heart or systemic conditions. The underlying condition can be life-threatening, so new chest pain, fainting, severe shortness of breath or other serious symptoms require urgent care.
What causes multifocal atrial tachycardia?
Lung disease is the most common association, especially chronic obstructive pulmonary disease. Other associations include respiratory failure, infection, coronary artery disease, heart failure, low potassium, magnesium or sodium, cancer, diabetes, major surgery, kidney failure, and rarely pulmonary embolism or heart valve disease.
What are the symptoms of MAT?
Most people have no symptoms. Possible symptoms include chest pain, palpitations, shortness of breath and fainting. Symptoms may also come from the condition causing MAT.
What is the heart rate in MAT?
The heart rate is more than 100 beats per minute and may reach 150 beats per minute.
How is MAT diagnosed?
An ECG or EKG is used to diagnose MAT. Providers examine the rhythm and P waves. A chest X-ray, blood tests or rarely an echocardiogram may be added to evaluate the underlying cause.
What does MAT look like on an ECG?
MAT appears as a fast, irregular rhythm with multiple abnormal atrial signals. Providers examine P waves to distinguish MAT from atrial fibrillation. Only a qualified professional should interpret an ECG.
How is MAT different from atrial fibrillation?
Both affect the heart’s upper chambers and can look similar. Providers distinguish them by reviewing the P waves on an ECG. About half of people with MAT develop atrial fibrillation or atrial flutter.
How is MAT treated?
Treatment usually addresses the condition causing the rhythm. Depending on the situation, a clinician may use beta-blockers, magnesium, potassium or calcium channel blockers. Rarely, AV node ablation and a pacemaker may be needed.
Does MAT go away?
MAT usually goes away once the underlying cause is treated. Some people need a beta-blocker or calcium channel blocker temporarily, and long-term follow-up may be needed for chronic heart or lung disease.
What are MAT medication side effects?
Possible side effects include dizziness, headache, upset stomach, diarrhea and constipation. Report concerning symptoms to the prescribing clinician and seek urgent care for chest pain, fainting or severe breathing difficulty.
What is the prognosis for MAT?
Prognosis depends on the underlying condition. A broad in-hospital death rate of 30% to 60% is described for people with MAT, but the underlying diseases—not the rhythm alone—can be fatal. This statistic cannot predict an individual outcome.
Can MAT be prevented?
Keeping heart or lung conditions from getting worse may reduce risk. Follow the treatment and follow-up plan for chronic disease, and ask your clinician which symptoms should prompt urgent care.
When should I go to the hospital for MAT symptoms?
Seek urgent medical care for chest pain, fainting, severe or worsening shortness of breath or other serious symptoms. Do not wait to confirm the rhythm yourself.
References
National Heart, Lung, and Blood Institute (NHLBI). What Is an Arrhythmia? National Institutes of Health. Last updated March 24, 2022. https://www.nhlbi.nih.gov/health/arrhythmias
National Heart, Lung, and Blood Institute (NHLBI). What Is COPD? National Institutes of Health. Last updated November 8, 2024. https://www.nhlbi.nih.gov/health/copd
McCord J, Borzak S. Multifocal atrial tachycardia. Chest. 1998;113(1):203-209. PMID 9440591. https://doi.org/10.1378/chest.113.1.203
Goudis CA, Konstantinidis AK, Ntalas IV, et al. Electrocardiographic abnormalities and cardiac arrhythmias in chronic obstructive pulmonary disease. Int J Cardiol. 2015;199:264-273. PMID 26218181. https://doi.org/10.1016/j.ijcard.2015.06.096
Chen H, Ma Y, Wang Y, et al. Progress of pathogenesis in pediatric multifocal atrial tachycardia. Front Pediatr. 2022;10:922464. PMID 35813391. https://doi.org/10.3389/fped.2022.922464
Disclaimer
This article is for general educational purposes and is not a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified healthcare professional with any questions about a medical condition or treatment.
A qualified clinician should interpret rhythm strips, symptoms, oxygen levels, blood tests, medication choices and the underlying heart or lung condition. Do not start, stop or change a heart medicine without medical guidance. Seek urgent medical care for chest pain, fainting, severe or worsening shortness of breath or other serious symptoms.
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