Severe Lyme Carditis in a 15-Year-Old Boy

Severe Lyme carditis in an adolescent can present with life-threatening arrhythmias requiring emergency intervention. A 15-year-old boy with a heart rate of 300 beats per minute developed ventricular tachycardia requiring cardioversion and temporary pacing. After antibiotic treatment, his heart block resolved completely, and he remained symptom-free at one-year follow-up.

Emergency Presentation

Medics found the boy pale, with a heart rate of 300 beats per minute and an unstable wide complex tachyarrhythmia. He was given amiodarone but remained in ventricular tachycardia.

This presentation was immediately life-threatening. At this rate, the ventricles cannot fill adequately, severely compromising cardiac output. Ventricular tachycardia can deteriorate into cardiac arrest within minutes if not treated promptly.

Hospital Deterioration

At the hospital, his blood pressure dropped to 66/30 mm Hg, and his symptoms worsened. “After a trial of anti-arrhythmic medication, his clinical condition declined, necessitating synchronized cardioversion,” writes Nawrocki.

Synchronized cardioversion was required to restore a stable rhythm after medications failed.

Transfer and Diagnosis

After stabilization, he was transferred to a cardiac ICU, where he was diagnosed with third-degree heart block following ventricular tachycardia.

This combination of fast and slow arrhythmias reflects significant electrical instability from Lyme carditis.

Empiric Treatment Initiated

Doctors suspected Lyme disease and started intravenous ceftriaxone before confirmation. The diagnosis was later confirmed by Western blot.

Early empiric treatment was critical and likely life-saving.

Temporary Pacing Required

Due to ongoing bradycardia and hypotension, the patient required a temporary pacemaker to maintain adequate heart rate and blood pressure.

Recurrent Arrhythmias During Treatment

Despite treatment, the patient experienced three additional episodes of ventricular tachycardia, two requiring cardioversion.

This highlights that cardiac instability can persist during early treatment, requiring close ICU monitoring.

Resolution and Recovery

After several days of intravenous antibiotics, the patient’s heart block resolved and the pacemaker was removed.

He was discharged on day 12 and remained symptom-free at one-year follow-up, with no lasting cardiac complications.

Clinical Significance

This case demonstrates that severe Lyme carditis can present with life-threatening arrhythmias in adolescents but may still be fully reversible with appropriate treatment.

Early recognition, ICU monitoring, and timely antibiotic therapy are essential to prevent fatal outcomes and avoid permanent cardiac damage.

Frequently Asked Questions

Can Lyme disease cause ventricular tachycardia in teenagers?
Yes. Although less common than heart block, Lyme carditis can cause ventricular tachycardia.

Can adolescents fully recover from severe Lyme carditis?
Yes. This case demonstrates complete recovery with no long-term complications.

Do children with Lyme carditis need permanent pacemakers?
Usually not. Temporary pacing is often sufficient until conduction recovers.

Why can arrhythmias continue after treatment begins?
Inflammation and electrical instability may persist temporarily even after antibiotics are started.

Is Lyme carditis life-threatening?
Yes. Severe cases can lead to cardiogenic shock and require emergency intervention.

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Clinical Takeaway

Severe Lyme carditis can be life-threatening but is often reversible with prompt diagnosis and treatment.

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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