Atrial Premature Complexes

Introduction to atrial premature complexes

Atrial premature complexes (APCs) are a commonly occurring form of heart arrhythmia characterized by premature heartbeats emanating in the atria. It can also be referred to as premature atrial contractions. A very predominant symptom in this condition is heart palpitations where one is aware of some unusual heartbeats. APCs happens when there is a premature beat, that is, a beat that occurs early during the heart cycle.

APCs make you feel like your heart missed a beat or that it paused briefly. On rare occasions, APCs can be a sign of a serious condition such as a fatal arrhythmia.

When the premature beat happens in the upper compartment of the heart, it is known as atrial complex or contraction. Premature beats can also occur in the ventricles (lower chambers of the heart) and are called ventricular complexes or contractions. The causes of both atrial and ventricular premature beats are similar.

Causes of atrial complexes

The sino-atrial node located in the upper chamber of the heart contains cells and functions to regulate the pace of the heartbeat through electrical signals. The ventricles are responsible for pumping blood but sometimes, these ventricles send out signals earlier than the usual normal rhythm. A pause follows this and later, a stronger second beat ensues as the pause allows more time for blood to fill the heart chamber.  

The exact cause of this premature heartbeat is usually unknown but Cardiac health has reported that the majority of the people who have APCs usually do not have heart disease. The following conditions will cause an increased frequency of occurrence of premature heartbeats, thereby making the symptoms easily noticed:

• Caffeine intake
• Alcohol use
• Stress
• Fatigue or lack of adequate sleep
• Medications that cause irregular heartbeat as a side effect

APCs may be indicative of an extra connection in the heart’s electrical system. These additional connections may cause the heart to beat irregularly at times. Even though this may be annoying, it is not harmful except these premature beats to occur often and affect the quality of life.

Some of the time, premature beats occur as a result of an injury to the heart or underlying heart disease. Make sure that your doctor examines you if you suddenly start to experience missed heartbeats or if the heart does not feel like it used to so that the underlying problem can be recognized.

Symptoms of atrial premature complexes

Most people with APCs do not manifest symptoms. You may experience premature beats but unaware of it. If you do feel the beats, you may recognize any of the following feelings when they occur:

• Feel as if the heart missed a beat
• Heartbeats are transiently stronger or intensified
• A fluttering sensation around the heart

The following symptoms may be seen in APCs. They can also be seen in other conditions that are often confused with APCs. They could be indicative of a very severe heart condition. Seek prompt medical care if you have any of the following:

• A racing or missed sensation around the heart, alongside fainting or lightheadedness
• Become sweaty or pale when you are aware that the heartbeats have changed the pace
• Chest pain
• Difficulty in breathing
• Having more than six instances per minute of heartbeat occurring in groups of three or more
• A resting pulse rate more than 100 beats per minute

Underlying conditions

APCs are sometimes indicative of a more serious condition. If you experience any skipping of the heart, abnormal racing or pounding in association with any of the symptom, seek good medical care.

The likely underlying conditions include:

• Severe arrhythmia that may cause a stroke or heart failure
• Heart disease, such as infection, genetic defects, and narrow or occluded blood vessels.
• Hypertension
• Valvular malfunction – malfunction of the atrioventricular (AV) valve
• Ventricular tachycardia, characterized by rapid heart rate and can lead to heart attacks

 If your premature beats occur more frequently in the absence of other symptoms, the beats may not be dangerous. But be on the look-out and seek treatment at any point you notice a new sensation in the heart which has not been discussed with a doctor before.

Diagnosis of atrial premature complexes

The doctor first asks some questions such as any sensation of a racing, missed, or pounding heartbeat. They may likely ask about when you first noticed the symptoms and what you were doing then.  They will also ask about your medical history.

The following symptoms are indicative of heart disease and may require a detailed exam, even if APCs do not occur with any others symptoms:

• Diabetes
• High blood cholesterol level
• High blood pressure
• Being overweight
• Smoking
• Family history of heart disease

The doctor can also perform a physical examination to check for indicators of underlying problems and monitor heart functionality. The things that are done include listening to the heartbeat, blood tests to monitor the chemistry and cholesterol levels, and testing your blood pressure.

If the examination suggests that there may be an underlying problem that may trigger the APC, the doctor will monitor the heart. The pattern of disruption will help the doctor to know the background cause of the APC. This is achieved by conducting an electrocardiogram, a test that measures the electrical activities of the heart either at rest or during exercise.

Learn more about electrocardiogram

A monitor may be worn for 24 to 48 hours or when the symptoms happen. The monitor is worn under the cloth to record the rhythm of the heart as you proceed with your daily activities.

Treatment of premature atrial complexes

Seek treatment whenever you notice a change in your heartbeat that has not been discussed with a doctor. Majority of the time, APCs may not require extra care after an initial examination. If the doctor says your APC is not harmful, you may not need to see the doctor if you experience the symptoms again, unless they are frequent, occurring with symptoms, or your doctor gives different instructions.

If the doctor says your APC is harmful, treatment is usually directed at the underlying condition that triggers the premature heartbeat. Your doctor will recommend a plan that works best for you based on the results of your exam.

APCs can be so frequent at times such that they can interfere with your daily life. In such a case, the doctor will prescribe drugs such as beta-blockers, or drugs used to treat severe cases of arrhythmia. These drugs particularly reduce contractions.

Prevention of premature atrial complexes

Mild cases of APCs can be prevented by avoiding drugs such as recreational drugs, tobacco, alcohol, and caffeine. Also, try to practice cardiovascular exercise regularly. It is beneficial to reduce your stress level by taking anti-anxiety drugs or reducing stress as anxiety can increase the chances of developing APC. Maintain a healthy weight too and if you are meeting a doctor who is unfamiliar with your APC history, inform them about it so they do not prescribe drugs that may trigger APCs.