The heart is a muscle that works tirelessly to pump blood throughout our entire body. It consists of four chambers – two atria and two ventricles – and is controlled by a complex electrical system. Like a conductor leading an orchestra, this system sends electrical signals that trigger the rhythmic contraction of the atria and ventricles. These electrical signals originate in the atria. The atria also fill the ventricles, which then pump blood to all the organs. In healthy people, this rhythm is regular, with a resting heart rate typically ranging from 60 to 100 beats per minute.
A heart rhythm disorder or cardiac arrhythmia is when the heart does not beat at a normal, regular rate.
Extrasystoles refer to the premature heartbeats that occur between beats. When the premature heartbeat originates in the atria, it is called an atrial extrasystole or a premature atrial contraction.
Premature atrial contractions are generally benign. We all have them occasionally. They may give cause for concern if they occur frequently, in rapid succession, or result in disabling symptoms for patients. When they are very frequent, they can trigger other forms of atrial arrhythmia (atrial fibrillation or flutter) or junctional arrhythmia.
Several factors can contribute to premature contractions, including underlying heart conditions, stress, the consumption of alcohol, tobacco, coffee, and other stimulants, hyperthyroidism, and certain types of medication.
99%
The percentage of people aged 50 and over who have episodes of premature atrial contractions. This was established by a Swiss study from 2012 involving 9,000 adults. The vast majority of these premature contractions are asymptomatic.
Symptoms
In most cases and for most patients, premature contractions remain asymptomatic. However, for some patients, or if the premature contractions occur very frequently or in rapid succession, they can create a brief sensation of palpitations. In rare cases they may cause a very brief, sharp pain.
20,000
The maximum daily number of atrial and ventricular extrasystoles beyond which it is best to see a cardiologist. This number can be determined during one of the exams referred to in this article.
Diagnosis
An electrocardiogram (ECG or EKG) is used to definitively diagnose premature atrial contractions by providing an electrical recording of the patient’s heart rhythm.
There are now several methods for performing an ECG:
- A standard ECG can be performed during an appointment with your primary care physician, cardiologist or in the emergency room.
- A Holter ECG : this is performed using a device that continuously records the heart’s rhythm over a 24 to 72-hour period.
- Smart devices:
- Most smart watches and some smartphones (using the camera flash on your finger) can detect an irregular and rapid heart rhythm suggestive of atrial fibrillation, but they do not provide an ECG trace that can confirm the diagnosis with certainty. They then advise the user to schedule an appointment with a physician.
- Some connected watches and other “AliveCor” devices allow you to directly record an ECG trace which you can then share with your physician.
Treatment
In most cases, premature atrial contractions do not require any treatment. Treatment will only be recommended if they cause symptoms, become debilitating, occur too frequently or are of a certain type.
In any case, the first step is to remedy any factors that might trigger them if possible (e.g. smoking, alcohol, coffee).
Specific treatment includes:
- Medication that affects the number and frequency of premature contractions.
- An ablation procedure that targets the areas responsible for the extrasystoles and destroys them using one or more catheters inserted inside the heart.
Greater risks for women
In addition to the risk factors presented in this article, women are more likely to suffer from premature atrial contractions at certain periods of their life, including during menstruation, pregnancy and menopause.
Premature junctional contractions
In addition to premature atrial and ventricular contractions, premature junctional contractions can also occur. In this case, the arrhythmia originates at the junction between the atria and the ventricles.
Reviewed and approved by Romain Tixier, MD, Cardiologist at Bordeaux University Hospital (CHU)
