Premature junctional contraction

Premature Junctional Contraction (PJC) is a type of arrhythmia that originates in the atrioventricular junction (AV junction). This condition is characterized by an early or premature heartbeat that disrupts the regular rhythm of the heart.

Overview

A heart's normal rhythm is controlled by a group of cells in the right atrium known as the sinoatrial node (SA node). In a healthy heart, the SA node sends electrical signals that propagate through the atria, causing them to contract and pump blood into the ventricles. The signal then reaches the AV junction, which acts as a gatekeeper, delaying the signal before it moves into the ventricles. This delay allows the ventricles to fill with blood before they contract.

In the case of a Premature Junctional Contraction, the AV junction fires an electrical signal before receiving the signal from the SA node. This premature signal causes the ventricles to contract earlier than they should, resulting in an irregular heartbeat.

Symptoms

Many people with PJC may not experience any symptoms. However, when symptoms do occur, they may include:

• Palpitations - a feeling of skipped heartbeats, fluttering or "flip-flops," or feeling that your heart is "running away"
• Pounding in your chest
• Dizziness or feeling light-headed
• Shortness of breath
• Chest discomfort or pain
• Fatigue, especially during times of increased activity

Causes

The exact cause of PJC is not known. However, it is often associated with:

• Heart disease
• High blood pressure
• Electrolyte imbalance
• Certain medications
• Stress or anxiety
• Caffeine, alcohol, or tobacco use
• Heart surgery

Diagnosis

PJC is typically diagnosed through an electrocardiogram (ECG), a test that records the electrical activity of the heart. The ECG can show the early contractions and help the doctor determine if they are coming from the AV junction.

Treatment

Treatment for PJC is usually not necessary unless the patient is experiencing significant symptoms or if the PJC is associated with a more serious heart condition. In such cases, treatment may include:

• Medications to control the heart rate or rhythm
• Cardiac ablation, a procedure to destroy the area of the heart causing the irregular rhythm
• Pacemaker implantation, if the heart is beating too slowly

See also

• Cardiac arrhythmia
• Atrioventricular nodal reentrant tachycardia
• Premature ventricular contraction