Can Lyme Disease Increase the Risk of Atrial Fibrillation?
Atrial fibrillation has been reported in some patients with Lyme carditis.
One study found Lyme antibodies were more common in patients with AFib.
The findings suggest an association but do not prove causation.
Researchers have gained a better understanding of atrial fibrillation, also called AFib or AF, but many causes and risk factors remain incompletely understood. A 2020 study explored whether Lyme disease atrial fibrillation may be associated by examining prior exposure to Borrelia burgdorferi, the bacterium that causes Lyme disease.
“It is hypothesized that in some cases the AF [atrial fibrillation] might be a consequence of past low-grade myocarditis,” the authors explain. “One of the understudied, potential sources of carditis is Borrelia infection-causing Lyme disease and Lyme carditis.”
The authors looked at 113 adult patients with atrial fibrillation who were attending a cardiac clinic in Poland between 2018 and 2019 and compared them with 109 patients with no history of AFib. The mean age of study participants was 75.8 years, with 40% male.
Atrial fibrillation patients were more likely to have obesity, hypertension, chronic kidney disease, heart failure, and left atrial enlargement than patients in normal sinus rhythm.
Borrelia and the Heart
Multiple studies have shown that Borrelia bacteria can infect parts of the heart, including the conduction system, endocardium, cardiac muscle, cardiac blood vessels, and heart valves. This condition is known as Lyme carditis.
“The more common location for the [Borrelia] spirochete-associated inflammation are fibers at the base of the heart, basal interventricular septum, and perivascular regions,” the authors write.
Unfortunately, few intravital atrial biopsies are performed, so not much is known about atrial inflammation caused by Borrelia infections, especially in patients with atrial fibrillation.
There have been several case reports of atrial fibrillation in Lyme disease patients. However, most reported AF as an additional finding in patients with atrioventricular block associated with Lyme carditis.
More recent case reports continue to describe atrial fibrillation as an uncommon presentation of Lyme carditis. These reports do not prove causation, but they support considering Lyme carditis in selected patients with compatible symptoms, epidemiologic exposure, and unexplained rhythm or conduction abnormalities.
How Could Lyme Disease Contribute to Atrial Fibrillation?
Lyme carditis most often affects the heart’s electrical conduction system, which is why heart block is the best-known cardiac manifestation of Lyme disease. However, inflammation involving the myocardium, perivascular tissue, or atrial tissue could theoretically contribute to rhythm disturbances such as atrial fibrillation.
The authors suggested that past low-grade Borrelia-associated inflammation might contribute to atrial remodeling. They also raised the possibility that persistent antigens or cross-reactive antibodies could promote autoimmune injury affecting cardiac tissue.
These proposed mechanisms remain unproven. Atrial fibrillation has many well-established risk factors, including age, hypertension, obesity, heart failure, structural heart disease, sleep apnea, and thyroid disease. Lyme disease should be considered only in the appropriate clinical context, particularly when AFib occurs with heart block, recent tick exposure, erythema migrans, or other Lyme disease symptoms.
Study Findings
“The study showed that patients with AF [atrial fibrillation] are over 8 times more likely to have positive Borrelia antibodies,” wrote Szymanska and colleagues.
According to the authors, 34.5% of patients with AFib had positive Borrelia antibodies compared with only 6.4% of patients in normal sinus rhythm.
They also reported that the presence of anti-Borrelia IgG antibodies was a strong independent predictor of atrial fibrillation, with an odds ratio of 8.21, a 95% confidence interval of 3.08 to 21.88, and p<0.0001.
READ MORE: 12-year-old boy suffers cardiac arrest due to Lyme disease
The authors suggested two possible explanations for the higher prevalence of AFib in patients with positive Borrelia antibodies.
First, past low-grade Borrelia-associated inflammation could potentially contribute to atrial remodeling and atrial fibrillation.
Second, Borrelia burgdorferi may persist in the extracellular matrix for a long time and induce cross-reactive antibodies that react with self-components, resulting in autoimmune injury.
Study Limitations
The authors noted several important limitations. This was an observational study. It did not include confirmatory Western blot testing for all participants because of cost and availability. It was conducted at a single center, involved an older cardiac clinic population, and cannot determine whether Lyme disease directly caused atrial fibrillation.
An association is not enough to establish causation. Larger, better-designed prospective studies are needed to confirm whether Lyme disease increases the risk of atrial fibrillation.
Authors’ Conclusion
“Certainly, larger and better-designed studies are needed to confirm the association between Lyme disease and AF, but for now, it is important for physicians treating patients in endemic areas to consider Lyme carditis as a potential cause for [atrial fibrillation] AF.”
Frequently Asked Questions
Can Lyme disease cause atrial fibrillation?
Lyme carditis usually causes heart block, but atrial fibrillation has been reported in some cases. Current evidence suggests an association between Lyme disease exposure and AFib, but it does not prove that Lyme disease directly causes atrial fibrillation.
What is Lyme carditis?
Lyme carditis occurs when Borrelia burgdorferi affects the heart. It most often involves the cardiac conduction system and may cause heart block, palpitations, chest pain, shortness of breath, lightheadedness, or fainting.
Does atrial fibrillation mean you have Lyme disease?
No. Most patients with atrial fibrillation do not have Lyme disease. However, Lyme carditis should be considered in selected patients from endemic areas, especially when AFib occurs with heart block, tick exposure, rash, or other Lyme disease symptoms.
Can treating Lyme disease improve heart rhythm problems?
In Lyme carditis, heart rhythm and conduction abnormalities may improve with appropriate antibiotic treatment. However, atrial fibrillation has many causes, and treatment decisions should be guided by cardiology evaluation and the patient’s overall risk factors.
Should patients with AFib be tested for Lyme disease?
Routine Lyme testing is not needed for every patient with AFib. Testing may be appropriate when atrial fibrillation occurs with compatible Lyme symptoms, heart block, recent tick exposure, erythema migrans, or residence in an endemic region.
Clinical Takeaway
Most patients with atrial fibrillation do not have Lyme disease. However, in endemic regions, physicians should consider Lyme carditis in patients with new-onset AFib, especially when it occurs with heart block, recent tick exposure, erythema migrans, or other signs of Lyme disease.
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References
- Szymanska A, Platek AE, Dluzniewski M, Szymanski FM. History of Lyme Disease as a Predictor of Atrial Fibrillation. Am J Cardiol. 2020;125(11):1651-1654.
- Barkhordarian M, Grijalva M, Kolla A, Stein A, Nemirovsky D. Harbinger of Lyme Carditis: From Atrioventricular Block to Atrial Fibrillation. J Community Hosp Intern Med Perspect. 2024;14(4):71-74.
- Zainal A, Hanafi A, Nadkarni N, Mubasher M, Lingutla D, Hoefen R. Lyme carditis presenting as atrial fibrillation. BMJ Case Rep. 2019;12(4):e228975.
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
I was diagnosed with A Fib in 2017 after a bad reaction to Targretin and Levothyroxine, taken for NHL.
Only God knows if the Bb and Babesia, acquired in 1995, contributed to the pathology.
Are there Lyme cardiologists in the US…or at least cardiologists who understand Lyme Disease and the devastation it causes in the body?
I use cardiologist primarily to be sure I have not overlooked another illness.
I use cardiologist primarily to be sure I have not overlooked another illness.
Are there Lyme cardiologists in the US…or at least cardiologists who understand Lyme Disease and the devastation it causes in the body?
We are in Michigan and I just had the family practice tell me my husbands joint quick onset and AFIB and my joints also Lyme (my test is positive) infected have nothing to do with Lyme. My gosh we need Kennedy to step in for this.
There are so many causes of a fib. In some cases the cause has never been identified. I have included Lyme disease in my evaluation particularly if there are other issues including joint pain.
In 2008 I was taking a shower and notice the right calf of my leg was swollen and had a big bullseye redness on it. I did not see a tick but we live in the on a mountain in PA and often get tick bites. I went to the doctor who said she thought it was a tick bite and gave me 3 antibiotics pills to take. Since then I have large knees that are painful and hot and I am very tried a lot. My hands are sore mostly my thumbs. I see floating color spots and my eye site blurry. I did get checked about 5 years after the bite again for limes and it came back all but one marker was positive for limes so I was told o do not have limes disease. I now have AFib. And I often wonder did they miss diagnose me?
I have not found the laboratory tests all that reliable. I have had to treat some of my patients based on clinical judgement rather than relying solely on the test. I have always encouraged someone who has bee ill for years after a tick and rash to be reevaluated by a doctor experienced in treating Lyme disease. BTW I would not be comfortable with “3” doxycycline after a tick bite.
During the summer of 1998 I was walking home in a pair of shorts due to hot weather, when I returned home I noticed a slight itching on the shin of my leg, I went to bed and when I awoke the next morning my leg had swelled up considerably and there was a red bullseye mark. I went to see my GP and he told me to go straight to the emergency dept. I was kept in hospital for 3 nights to treat the bite and returned home. Approx 3 years later I began having palpations which eventually was diagnosed as atrial fibrillation (lone afib). Could there be a link to the bite and the afib?
There are so many causes of atrial fibrillation. I reported on a published case in my blog to encourage doctors to look a second time for Lyme disease.
I had Lyme disease in 2008 treated with 3 months of iv rocephin. I have had afib not crontrolled well for several years. This winter had heart failure due to the afib. They tried to do electro cardoiversion which worked for a few days but returned to afib. I am on metoprolol, jardiance, lasix, xarelto and losartan. The electrocardiologiat said abblation will likely not work and rec to do a pacemaker. Want to be sure this is the right approach .
There are so many causes of atrial fibrillation to consider. I still look for evidence of a tick borne illness.
I had a cardiac ablation at John’s Hopkins less than two years ago for SVT (Holter Monitor captured 230 bpm for 23 mins). I’d been previously diagnosed twice (2 different strains) with Lyme disease. I asked then if the Lyme had produced this, since I’d not had heart issues before infection. It was unknown. Since the procedure, I have not had an episode of tachycardia. I’ve learned that about 30% of the population seems to have chronic Lyme symptoms, and I was being treated with pulse doses of antibiotics for continuing symptoms. I guess I’m wondering if I’d be a candidate for an atrial biopsy at any point. Thank you for your dedication to this.
I prescribe daily treatment in my practice.
I have had palpitations on and off for some years. A few months ago I experienced them again and the next day noticed a tick on my leg. The palpitations lasted about a week. Could a tick bite cause palpitations in isolation or should I be checked for Lymes disease?
Palpitation can occur in isolation. Palpitations can indicate POTS, a condition seen in Lyme disease. I also have had patients with both a history of Lyme and palpitations.
I developed afib in 2019, not long after I had found an embedded tick. I was not evaluated or treated for Lyme disease at the time. After a difficult year with increasingly severe afib symptoms that resisted other treatments, I had a cardiac ablation in July 2020 and the afib stopped. Three weeks ago, I found another tick on my leg, in February 2024. I have been diagnosed with Lyme disease this time . My afib has returned, unfortunately, despite two weeks of antibiotic treatment with doxycycline.
I included my understanding of the cardiac cases to encourage my colleagues to discuss the topic. I hope you resolve your issues.
Why are doctors so illiterate in treating diseases that have been around since the
70’s in the USA Really no excuse for this uneducated population. Lay people understand it better living with it. May god save us all.