What Is Lyme Carditis?

Lyme disease is a common tick-borne disease in the northern portion of the United States. Some diseases are caused by a virus, some by a fungus. However, Lyme disease comes from a bacteria called Borrelia burgdorferi. This bacteria transfers from black-legged ticks to humans, creating flu-like symptoms.

While it is possible to recover from Lyme disease without medical intervention, it is not recommended. Untreated Lyme disease can quickly start to affect other parts of the body, such as the heart. Within a few short weeks, this bacteria can enter the heart and begin attacking the heart muscle, creating a condition known as Lyme carditis.

This inflammation to the heart muscle tampers with and slows the heart’s electrical signals from the upper chamber to the lower chamber affecting your heartbeat and the amount of blood flow your heart pushes to the rest of your body. This creates a medical condition known as an atrioventricular block or conduction disorder; it is best known as heart block.

This article covers the symptoms, diagnosis, treatment, prevention, and prognosis of Lyme carditis.

Symptoms

Lyme disease tends to create flu-like symptoms, such as a fever, headache, muscle aches, swollen lymph nodes, and a rash. With Lyme carditis, you may experience those symptoms along with:

• Lightheadedness
• Dizziness
• Fainting
• Shortness of breath
• Palpitations
• Chest pain

Diagnosis

In order to be diagnosed with Lyme carditis, you must see a healthcare provider. Since you will have flu-like symptoms for a few weeks before Lyme carditis is triggered, you may have already visited your healthcare provider.

Your healthcare provider will likely request an electrocardiogram (ECG) to check your heart’s electrical signals. This test will help them decide the severity of your particular case.

They may also request a blood draw to see if there is any indication of a tick bite. However, the lab tests are not always reliable.

Treatment

Lyme disease is highly treatable when caught early. The longer Lyme disease goes unchecked, the more likely you will experience more severe and long-term problems with your joints, nervous system, and heart.

Luckily, those who experience heart block due to Lyme disease can have their symptoms reversed using antibiotics instead of more invasive treatment options. However, severe lyme carditis does require hospitalization.

Lyme carditis is treatable with an antibiotic such as:

• Doxycycline
• Amoxicillin
• Cefuroxime

Depending on how severe your case is, you will either get a prescription or receive ceftriaxone through an IV. 

Prevention

Preventing Lyme carditis means preventing Lyme disease. To avoid both conditions, you must prevent tick bites.

To prevent tick bites:

• Use a tick repellent on your clothing and skin. 
• Conduct a full-body tick check when coming inside—especially when spending time in grassy fields, forests, or dog parks. 
• Bathe or shower when you come in from the outdoors. 
• Check your pets for ticks, and bathe them occasionally with a tick shampoo.

To avoid contact with ticks:

• Avoid wooded and brushy areas with high grass and leaf litter.
• Walk in the center of trails.

The longer a tick is attached to your body, the more likely you are to get Lyme disease. According to the Centers for Disease Control and Prevention (CDC), if you remove the tick within 24 hours, your chance of being infected is very low.

Prognosis

Most people panic—and rightfully so—when their heart is in trouble. Statistically speaking, there is good news for those with Lyme carditis, though: From 1985 to 2019, only 11 cases of Lyme carditis were fatal worldwide.

According to the CDC, Lyme carditis affects one in every 100 people with Lyme disease. Those who seek treatment tend to have the best outcomes.

Most people with heart block caused by Lyme carditis can completely turn around within one week. More minor heart issues will resolve at about the six-week mark. 

A Word From Verywell

If you develop a fever or rash within a month of being bit by a tick, seek medical care. These are the initial signs of Lyme disease. Seeking treatment before Lyme disease progresses is the best way to prevent Lyme carditis.