Reversible heart block from Lyme disease means patients don’t need permanent pacemakers for life. Two cases demonstrate successful removal of permanent pacemakers after antibiotic treatment restored normal cardiac conduction. Both patients maintained 1:1 conduction at heart rates exceeding 120 beats per minute during exercise stress testing, proving their heart block had completely resolved.

Pacemaker Removal: Proof of Reversibility

In their study “Pacemaker Explantation in Patients With Lyme Carditis,” Wamboldt and colleagues describe two cases involving the removal of pacemakers in patients with Lyme carditis, which highlights the importance of including Lyme carditis in the differential diagnosis for high-degree AV block.

Furthermore, these cases demonstrate the “benefits of early device interrogation in patients who have been treated for Lyme carditis and received a pacemaker during their treatment,” the authors explain.

These cases prove that heart block from Lyme disease is truly reversible — not just theoretically but practically, with permanent pacemakers successfully removed after conduction normalizes.

Understanding Lyme Carditis Conduction Disorders

Lyme carditis can lead to cardiac arrhythmias and conduction disorders, most commonly atrioventricular (AV) blocks.

When Borrelia burgdorferi spirochetes infiltrate the heart’s electrical conduction system, they disrupt the transmission of electrical signals from the atria to the ventricles. This disruption manifests as varying degrees of heart block — from first-degree (slowed conduction) to complete block (no conduction).

The critical question these cases address: once pacemakers are implanted, must they remain permanently, or can they be removed after antibiotics resolve the infection?

Case 1: 48-Year-Old Woman with Complete Heart Block

“A 48-year-old woman presented with shortness of breath and dizziness secondary to complete heart block,” the authors write. “Given the presence of symptomatic bradycardia, she was transferred to a tertiary hospital for pacemaker implantation.”

The presentation was classic for severe Lyme carditis: complete (third-degree) heart block causing symptoms from inadequate heart rate. With no electrical conduction between atria and ventricles, her heart couldn’t maintain adequate cardiac output for normal activities.

She had a non-specific rash on her abdomen 3 months before symptom onset.

This timeline is typical — cardiac symptoms develop weeks to months after initial tick bite, often after the rash has resolved. The three-month gap meant she likely didn’t connect the rash to her current cardiac symptoms.

Lyme disease testing was positive.

Case 2: 58-Year-Old Man with Atrial Fibrillation and Pauses

A 58-year-old man presented with dizziness, syncope, headache and myalgia. “His initial electrocardiogram showed atrial fibrillation with slow ventricular response,” the authors write. “During his admission he experienced symptomatic pauses lasting 4 to 10 seconds.”

This case demonstrates the diverse cardiac manifestations of Lyme disease. Rather than classic heart block, he presented with atrial fibrillation — an irregular rhythm — combined with dangerously slow ventricular response and pauses up to 10 seconds.

Ten-second pauses are life-threatening. During these pauses, no blood flows to the brain or vital organs. The dizziness and syncope resulted from inadequate cerebral perfusion during these episodes.

He also had a pacemaker implantation.

Lyme disease testing was positive.

Both patients were treated successfully with antibiotics.

Why Permanent Pacemakers Were Placed

Typically, Lyme disease patients with conduction problems are placed on a temporary pacemaker. In both of these cases, the patients were placed on a permanent pacemaker.

This is the critical issue. Standard practice for Lyme carditis is temporary pacing — using external pacemakers or temporary leads that can be removed once antibiotics restore conduction. Permanent pacemakers should be avoided when possible, especially in younger patients who would require decades of device management.

Why were permanent devices implanted in these cases? Several possibilities:

• Lyme disease not recognized initially: If carditis wasn’t diagnosed as Lyme-related, standard cardiac practice would be permanent pacing for symptomatic complete heart block
• Hemodynamic instability: Severe symptoms may have necessitated rapid permanent device placement before Lyme diagnosis was confirmed
• Institutional practice patterns: Some centers may default to permanent devices rather than temporary approaches
• Patient preference or circumstances: Temporary external pacing requires hospitalization; permanent devices allow earlier discharge

Regardless of why permanent devices were placed, these cases demonstrate they can be successfully removed after treatment.

Exercise Testing Proves Conduction Recovery

On follow-up, both pacemakers were functioning. “Both patients underwent exercise stress testing and were able to maintain 1:1 conduction at heart rate >120 beats/min,” according to the authors.

This testing was essential to prove heart block had resolved. “1:1 conduction” means every electrical signal from the atria successfully conducted to the ventricles — no dropped beats, no delays. Maintaining this during exercise with heart rate exceeding 120 bpm demonstrates that conduction was robust even under physiologic stress.

The exercise testing served two purposes:

1. Verification of recovery: Proved the AV node had healed and could handle normal conduction demands

2. Safety assessment: Ensured patients wouldn’t develop exercise-induced block (as seen in other Lyme carditis cases) if the pacemaker was removed

Successful Pacemaker Removal

The permanent pacemakers were removed successfully.

Pacemaker explantation involves extracting both the generator (battery/computer unit) and the leads (wires attached to heart muscle). This is more complex than initial implantation because leads can become embedded in heart tissue over time.

“Within the first year of insertion, transvenous lead extraction has a high success rate and a low complication rate,” the authors explain. The pacemaker is more difficult to remove if present over a year due to fibrotic changes.

This timing consideration is critical. As leads remain in place, fibrous tissue grows around them, essentially scarring them into the heart. Early removal (within the first year) is much safer and easier than later removal.

Importance of Early Follow-Up

“This highlights the importance of close follow-up so that early pacemaker explantation can be arranged if clinically indicated,” the authors suggest.

The clinical implication: patients with permanent pacemakers placed for Lyme carditis should be followed closely after antibiotic treatment. Once conduction recovery is documented, explantation should be considered promptly — within the first year when removal is safest.

Waiting years to remove the device means more difficult extraction with higher complication rates. The window for easy removal is limited.

Authors’ Key Takeaway

“Pacemaker explantation is a potential option for patients with treated Lyme carditis who have undergone proper testing to ensure that normal cardiac conduction has resumed.”

This statement deserves emphasis. Even when permanent pacemakers are implanted, they don’t have to remain permanent in Lyme carditis patients. With proper testing to confirm conduction recovery and timely explantation within the first year, patients can avoid decades of device dependence.

Clinical Implications

These cases challenge the assumption that “permanent pacemaker” means permanent in Lyme carditis. The reversibility of heart block from Borrelia burgdorferi infection means devices placed during acute illness can be removed once antibiotics restore normal conduction.

For patients, this is critically important. A permanent pacemaker means:

• Battery replacement every 7-10 years requiring surgery
• Lead complications including fracture, dislodgement, or infection
• MRI restrictions (though newer devices are MRI-conditional)
• Activity limitations
• Psychological burden of device dependence
• Cumulative healthcare costs exceeding hundreds of thousands of dollars over a lifetime

For a 48-year-old woman or 58-year-old man, avoiding permanent pacing means 30-40 years without these burdens.

Clinical Perspective

These cases validate what we’ve long understood about Lyme carditis: it’s reversible. But they go further by demonstrating that even when permanent pacemakers are implanted — perhaps prematurely, before Lyme diagnosis was confirmed — they can be successfully removed after treatment.

The key is systematic follow-up. Patients need:

1. Post-treatment monitoring: Regular ECGs and Holter monitoring to document conduction recovery

2. Exercise stress testing: Proof that conduction remains stable under physiologic stress

3. Pacemaker interrogation: Review of device data showing how often the pacemaker actually fires

4. Timely explantation: Removal within first year when technically easiest and safest

The exercise testing showing 1:1 conduction at >120 bpm is particularly valuable. This demonstrates that patients’ AV nodes function normally even during exertion — the exact situation where exercise-inducible block would appear if conduction hadn’t fully recovered.

From a broader perspective, these cases reinforce why temporary pacing should be the default approach for Lyme carditis patients. While permanent devices can be removed, it’s better to avoid implanting them initially. Temporary approaches — external pacemakers or temporary transvenous leads — provide necessary cardiac support during treatment while avoiding the complexities of later device removal.

However, when permanent devices are placed (whether due to diagnostic uncertainty, institutional practices, or clinical necessity), these cases prove that reversal is possible. Patients shouldn’t be told “you’ll have this pacemaker for life” until recovery is fully assessed and removal attempted if appropriate.

Frequently Asked Questions

Can heart block from Lyme disease be reversed?

Yes. These cases prove reversible heart block from Lyme disease with successful pacemaker removal after antibiotic treatment. Both patients maintained normal 1:1 conduction during exercise stress testing, demonstrating complete recovery of cardiac conduction.

Can permanent pacemakers be removed from Lyme carditis patients?

Yes. Both patients had permanent pacemakers successfully explanted after antibiotics restored normal conduction. Removal within the first year has high success rates and low complication rates before significant fibrotic changes occur.

How do doctors know when it’s safe to remove a pacemaker?

Exercise stress testing proving 1:1 conduction at heart rates >120 bpm demonstrates the heart can handle normal electrical demands without artificial pacing. Pacemaker interrogation showing minimal device usage confirms the patient’s intrinsic rhythm is adequate.

Should Lyme carditis patients get temporary or permanent pacemakers?

Temporary pacing is preferred when Lyme carditis is recognized, avoiding the need for later explantation. However, these cases show permanent devices can be removed if placed before Lyme diagnosis, so permanent placement isn’t irreversible.

How long after Lyme treatment before pacemaker can be removed?

The timeline varies but should be within the first year when lead extraction is easiest and safest. These patients required close follow-up with serial testing to document conduction recovery before explantation was attempted.

Why is early pacemaker removal important?

Leads become embedded in heart tissue over time through fibrotic changes. Removal within the first year has high success rates and low complications. After longer periods, extraction becomes progressively more difficult and risky.

What testing is needed before pacemaker removal?

Exercise stress testing to prove sustained 1:1 conduction at elevated heart rates, pacemaker interrogation showing minimal device usage, and serial ECGs/Holter monitoring documenting stable intrinsic rhythm without conduction abnormalities.