Trusted, Compassionate Care for Conduction Disorders 

A conduction disorder affects the heart’s electrical system and how electrical impulses travel through the heart. When that signal slows or does not move through the usual pathway, the heartbeat may become slow, uneven or less coordinated. Some people notice symptoms right away. Others feel fine and only learn about their condition after testing. 

People often hear two terms that sound similar: rhythm and conduction. Your heart rhythm describes the pattern of your heartbeat. Conduction describes how the electrical signal moves through the heart to create that beat. Some conduction disorders can lead to cardiac arrhythmias, which are irregular heartbeats. 

At Keck Medicine of USC, we offer trusted, compassionate care for diagnosing and treating conduction disorders.  

Common Conduction Disorders 

There are different types of conduction disorders, and the type helps your care team choose the best treatment options. 

• Heart block: The electrical signal slows down or stops as it moves from the heart’s upper chambers (atria) to the lower chambers (ventricles). Heart block can range from mild signal delay to more serious forms that cause missed heartbeats or a slow heart rate. 
• Bundle branch block: This happens when the electrical signal does not travel down one of the usual pathways in the ventricles. Instead, it takes a different route, which can delay one ventricle by a fraction of a second and change how the heartbeat looks on testing. 
• Long QT syndrome (LQTS): This condition affects how the heart’s lower chambers reset between beats. When the reset takes too long, abnormal rhythms can occur, sometimes during exercise or stress.  

Symptoms of Conduction Disorders 

Some people feel nothing with a conduction disorder. Others notice symptoms that come and go, especially when they’re active or feeling tired. Symptoms may include: 

• Chest pressure or discomfort 
• Fainting, called syncope, dizziness or lightheadedness 
• Fatigue 
• Getting tired or short of breath with normal activity 

What Causes Conduction Disorders? 

Conduction disorders can have more than one cause. Some are tied to age-related changes in the electrical system. Others can be associated with heart disease or the effects of certain medications. Possible causes and risk factors include: 

• Cardiomyopathy or heart failure 
• Certain medications that slow the heart rate 
• Coronary artery disease 
• Electrolyte changes 
• Heart valve disease 
• Prior heart attack 
• Prior heart surgery or procedures 
• Thyroid disease 

How We Diagnose Conduction Disorders 

A clear diagnosis helps your care team match treatment to your rhythm pattern and choose the safest plan. Your visit starts with a review of your symptoms and medications, followed by an electrocardiogram (EKG/ECG) to record the rhythm. When symptoms come and go, heart rhythm monitoring, which can be done with a Holter monitor, helps capture changes during daily life. If episodes feel less frequent, longer monitoring may help. Additional evaluation may include an echocardiogram to assess the heart structure and valve health, blood work to check thyroid function and other cardiac imaging based on your history and symptoms. 

Treatment Options for Conduction Disorders We Offer 

Treatment depends on the type of conduction disorder, your symptoms and the results of testing. Some people only need observation and follow-up. If a slow heartbeat or pauses cause symptoms, a pacemaker or ICD placement may help. If symptoms come and go and the cause isn’t clear, a loop recorder implantation can capture rhythm events over time. In some cases, a conduction delay plus reduced heart pumping function may require cardiac resynchronization therapy (CRT). In higher-risk situations involving dangerous ventricular rhythms, your specialist may talk with you about ICD therapy.

Why Choose Us for Conduction Disorder Care

You get clear explanations of your test results and what they mean for your next steps.

Your care plan matches your type of conduction disorder, your symptoms and your risk.

Your care stays coordinated across evaluation, testing, treatment and long-term follow-up.

You have access to a full range of options, from monitoring and medication to device therapy when needed.