Atrial Tachycardia: Causes, Consequences and Treatments

What is atrial tachycardia?

Atrial tachycardia is a type of supraventricular arrhythmia characterized by abnormal excitation of the atria, resulting in an atrial rate ranging from 100 to 250 beats per minute. It is a relatively uncommon arrhythmia, accounting for approximately 5 -15 percent of all supraventricular tachycardia cases.

Atrial tachycardia may occur in paroxysms or persistently and may affect individuals with structurally normal hearts as well as those with underlying heart disease.

Classification of atrial tachycardia

Atrial tachycardia can be classified into focal atrial tachycardia and multifocal atrial tachycardia based on the number of abnormal firing foci in the atria. Distinguishing between these types is essential for guiding appropriate treatment and is based primarily on electrocardiogram characteristics and pathological mechanism.

Focal atrial tachycardia

Focal atrial tachycardia, also known as focal atrial tachycardia, originates from a single abnormal focal point in the atria and does not involve a reentry mechanism. It may occur in anyone, including those without structural heart disease, but it is more common in patients with conditions such as ischemic heart disease, valve disease or heart failure.

On ECG, focal atrial tachycardia shows a P wave preceding each QRS complex, but with an abnormal morphology compared to the sinus P wave. The heart rhythm is usually regular, with rates ranging from 100 to 250 beats per minute. The PR interval may be normal or prolonged depending on the location of the focus.

Multifocal atrial tachycardia

Multifocal atrial tachycardia results from multiple abnormal firing foci in the atria, causing chaotic atrial depolarization. It is closely associated with chronic lung disease, especially chronic obstructive pulmonary disease.

On ECG it is characterized by at least three distinct P‑wave morphologies in a single lead, varying PR intervals, and an irregular ventricular rhythm, which can be mistaken for atrial fibrillation. Atrial rates typically range from 100 to 150 beats per minute.

Symptoms of atrial tachycardia

During an atrial tachycardia episode, the heart beats at 100 – 250 beats per minute, reducing cardiac pumping efficiency. Some patients may be asymptomatic, especially if the rate is moderate or the heart has adapted. When symptoms do occur, they often include palpitations that appear suddenly and may last anywhere from a few minutes to several hours.

Other associated symptoms may include chest discomfort in patients with underlying heart disease shortness of breath dizziness excessive sweating fatigue or exhaustion after the episode nausea fainting if the heart rate is excessively high causing reduced cardiac output.

In infants and young children the condition can be difficult to recognize since they cannot describe their symptoms. Signs may include poor feeding reduced intake sweating during feeding or crying irritability lethargy pale or bluish lips and rapid breathing with chest retractions. These signs warrant prompt evaluation and treatment.

Causes of atrial tachycardia

In healthy individuals the heart beats normally at 60 -100 beats per minute thanks to the cardiac conduction system which starts at the sinoatrial node in the right atrium and travels through the atria the atrioventricular node bundle of His and Purkinje fibers to the ventricles resulting in synchronized atrial and ventricular contractions.

In atrial tachycardia abnormal electrical impulses originate from one or more ectopic foci in the atria causing contraction rates of 100 – 250 beats per minute. This disrupts atrioventricular synchrony and impairs hemodynamic efficiency.

Multiple factors contribute, including hypertension heart failure coronary artery disease valve disease cardiomyopathy congenital heart defects chronic pulmonary disease (such as asthma COPD pulmonary embolism thyroid disorders diabetes post‑cardiac surgery excessive alcohol cocaine or stimulant use. In some cases atrial tachycardia occurs without any obvious underlying cause and is called idiopathic atrial tachycardia.

Impact on health

Depending on heart rate severity duration and presence of comorbid conditions atrial tachycardia may cause serious health effects: heart failure – prolonged tachycardia reduces cardiac output forcing the heart to work harder eventually leading to or worsening heart failure stroke risk, rapid atrial contraction promotes clot formation in the atria though less than atrial fibrillation assessment is still required in high‑risk individuals secondary arrhythmias—atrial tachycardia can trigger more dangerous arrhythmias such as atrial fibrillation or atrial flutter worsening of underlying disease—torsional effects on patients with coronary disease and chronic pulmonary disease by increasing oxygen demand reducing cardiac output leading to pulmonary congestion increasing dyspnea and possibly right heart failure quality of life impairment—symptoms such as palpitations dizziness fatigue anxiety impaired sleep and concentration can lead to chronic stress anxiety or depression affecting daily activities

Diagnosis of atrial tachycardia

Diagnosis involves detailed patient history family history symptom assessment and physical exam including heart rate and blood pressure.

Investigations may include ECG to detect abnormal P waves and arrhythmic features Holter monitoring for capturing intermittent episodes echocardiography to evaluate structural heart disease blood tests to assess electrolytes and thyroid function stress testing for exercise‑induced episodes and electrophysiology study involving intracardiac mapping to identify focal sites and possibly perform ablation.

Treatment of atrial tachycardia

Choice of treatment depends on frequency symptom severity underlying cause and cardiac comorbidity. Goals are to control rate terminate tachycardia and prevent recurrence. Main approaches include:

• Medication – beta blockers calcium channel blockers or antiarrhythmics to control rate and symptoms anticoagulants if left‑sided heart disease or clot risk present
• Electrical cardioversion – controlled shock under sedation to restore sinus rhythm
• Catheter ablation – radiofrequency ablation of the arrhythmogenic focus guided by electrophysiologic mapping
• Pacemaker implantation – considered when atrial tachycardia is associated with conduction disturbances or post‑ablation bradycardia

Treatment for atrial tachycardia must be individualized. Patients should follow doctor’s instructions use medications as prescribed and attend regular follow‑up appointments.

Việt‑Pháp Hospital Hanoi offers advanced expert care in diagnosis and treatment of atrial tachycardia with experienced cardiologists including Dr Alain Patrice Lebon MRCP, certified electrophysiologist, modern diagnostic tools including ECG Holter, echocardiography and 3D EnSite X mapping system, enabling precise catheter ablation and personalized treatment according to European Heart Rhythm Association guidelines.

Contact 024 3577 1100 to schedule a consultation.