Lyme Carditis: Symptoms and EKG Findings
A key pattern is conduction disturbance. Lyme carditis can disrupt the heart’s electrical system, leading to a wide range of abnormalities.
“[Lyme carditis] is caused by direct invasion of myocardial tissue by spirochetes and an immunological host response causing lymphocyte inflammation,” writes Marcos in a discussion of Lyme carditis diagnosis.
“Borrelia burgdorferi has a predisposition to cause inflammation of the atrioventricular (AV) node, resulting in variable conduction abnormalities.”
Start here: Lyme carditis symptoms guide
Who Develops Lyme Carditis?
A key pattern is demographic clustering. Certain groups may be more commonly affected.
The 18 patients with possible Lyme carditis were predominantly Caucasian males with a mean age of 44.5 years (range 24–79).
All patients met CDC surveillance criteria for Lyme disease.
- 1 patient had an erythema migrans (EM) rash with negative blood tests
- 17 patients had 2–3 IgM-specific bands
- 11 patients had 5 or more IgG bands
- 5 patients presented with an EM rash
A key pattern is early testing limitation. Some patients had clinical Lyme disease despite incomplete serologic confirmation.
Common Symptoms of Lyme Carditis
A key pattern is nonspecific presentation. Symptoms may not initially suggest a cardiac cause.
“The most common symptoms at presentation were chest tightness, dizziness, and dyspnea on exertion,” writes Marcos. Symptoms were present for 4–30 days.
These symptoms can overlap with other conditions, making early recognition challenging.
EKG Abnormalities in Lyme Carditis
A key pattern is variability. Lyme carditis can produce a wide range of EKG findings.
Among the 18 patients:
- 4 had AV block (1st and 2nd degree)
- 6 had right bundle branch block or conduction abnormalities
- 2 developed atrial fibrillation
- 3 had T wave inversion
- 1 had sinus bradycardia with ST elevation
- 2 had prolonged QT interval
A key pattern is AV node involvement. Atrioventricular conduction abnormalities remain the most common presentation.
The Spectrum May Be Broader Than Expected
A key pattern is expanding recognition. Lyme carditis may affect the heart in multiple ways.
Reported abnormalities include:
- Right or left bundle branch block (RBBB, LBBB)
- Widened QRS complex
- AV dissociation
- Atrial fibrillation
- Ventricular dysfunction
- Fulminant myocarditis
- Cardiac arrest
“The spectrum of ECG abnormalities in Lyme disease may be broader than previously suspected,” the authors conclude.
Clinical Interpretation
A key pattern is missed diagnosis risk. Cardiac symptoms may not immediately be linked to Lyme disease.
These findings suggest:
- Lyme carditis can present with diverse EKG abnormalities
- Symptoms may be subtle or nonspecific
- Early recognition is critical in endemic areas
“Clinicians should be aware of these ECG abnormalities that may be a sign of Lyme carditis,” the authors emphasize.
Clinical Takeaway
Lyme carditis can cause a wide range of EKG abnormalities, most commonly affecting the AV node.
Because symptoms may be nonspecific, diagnosis depends on recognizing clinical patterns and exposure risk.
In endemic areas, unexplained conduction abnormalities should raise suspicion for Lyme disease.
Related Articles:
Patients can die when Lyme carditis is not treated
References:
- Marcos LA, Castle PM, Smith K, Khoo T, Morley EJ, Bloom M, Fries BC. Risk factors for Lyme carditis: A case-control study. Eur J Prev Cardiol. 2019 Sep 19:2047487319876046.
Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.
Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention
Thank you for this important perspective. Dr. Cameron have you seen complex erratic blood pressures, with orthostatic hypertension, in your Lyme patients? It seems important to define such situations as having a neurological or cardiac basis ?
The problem is related in part to the effect of tick-borne illnesses on the autonomic nervous system. The issues are complex. There are POTS professionals that have described the complexity of these presentions. I find the problem is common in my patients.
Any information for connection between long-standing Lyme disease and extensive Aortic dissection.
I have read somewhere of Lyme interfering with collagen synthesis.
I was in the hospital a year ago. One doctor said he thought is was Lyme carditis. the cardiologist rolled his eyes at me and referred me to an elecrophysiologist. The diltiazem had my blood pressure @ 35/53 and terrible shortness of breath. I took myself off of it. He is located at Beth Israel. He wants to do a pulse field ablation for AFib. I was diagnosed with Lyme in 2020. Had your typical 3 weeks of doxy. My dentist puts me on doxy for his procedures. A small cut will lead to cellulitis. One cut on ankle and I had to go to a wound specialist. Back on doxy. I am 79 years old and I am scared to have the ablation. Infection and general anethesia frightens me. I saw what can happen with my mother and mother-in-law. I am of sound mind now and would hate to lose that. If I get an internal infection I’m doomed if no one notices it. Will this be dangerous for me? I get no explanations from anyone. My primary died in 2019 and I’ve had poor care since. Could I have a bit of advice?
Thank you for sharing this—your concerns are very understandable, especially given your past experiences and not getting clear answers.
I can’t provide individual medical advice here, but with complex issues like atrial fibrillation, possible Lyme involvement, and side effects from medications like diltiazem, it’s reasonable to ask for a clear explanation of risks and options—or seek a second opinion.
Your concerns about safety, infection, and quality of life deserve to be taken seriously.