Atrial tachycardia (AT) is a type of rapid heart rhythm abnormality that originates from a discrete focal area of the atria, or upper chambers of the heart. This disorder is sometimes called focal atrial tachycardia.
Symptoms of Atrial Tachycardia
Typical symptoms of atrial tachycardia are often similar to atrial flutter and atrial fibrillation. These include sudden palpitations, dizziness, trouble breathing, and syncope or passing out. Unlike AT, atrial flutter is not a small focal area of the heart but rather a large abnormal circuit often encompassing the whole atrium. Atrial fibrillation can have focal areas that sustain the rhythm but these are typically multiple and the rhythm pattern is irregular.
Causes and Treatment
AT can have numerous causes:
- Reversible AT due transient abnormalities in the body
- Congenital AT
- AT due to aging or other heart disease
- AT as a consequence of prior heart procedures such as surgery or cardiac ablation
Reversible AT can be due to temporary abnormalities such as very abnormal body electrolytes from dehydration. It’s easily treated by targeting the abnormality. Patients with congenital AT are born with it, often presenting in childhood or early adulthood. It can be controlled with medications or effectively with catheter ablation procedures.
AT can also be a consequence of aging or other heart disease causing progressive disease in the heart’s electrical system. This may lead to certain focal areas to have rapid electric beats. Management of this type of AT depends on a patient’s underlying health and typically consists of drugs to regulate the rhythm and/or catheter ablation.
One of the most common causes of AT today is a prior heart procedure. Children born with congenital heart disease that requires heart surgery often develop AT decades later in the regions of the heart where surgery was performed. With the growth of catheter ablation, AT has been noted to be a common arrhythmia in patients with symptoms that reoccur. These focal ATs are often located near previous ablation scars. Treatment of these post-procedural focal ATs is more difficult that other ATs and require either drugs or further procedures.