Lyme carditis

 Q: 44 years old male who was diagnosed with Lyme's disease 4 weeks ago is now admitted to ICU with syncope and Atrio-ventricular block (AV-block) on EKG. It would be prudent to insert a permanent pacemaker to avoid sudden cardiac death?

A) True

B) False

Answer: B

AV block due to Lyme carditis is usually short-lived and resolved in six weeks. A temporary pacemaker may be required, but a permanent pacemaker is rarely needed. While evaluating the EKG of a patient suspected of having Lyme carditis, it is important to pay attention to the PR interval. If the PR interval is more than 300 milliseconds, there is a high chance of the patient progressing to complete AV block, which may require a temporary pacemaker. 

Patients who fail to complete the antibiotic course appropriately for any early signs of Lyme disease, erythema migrans, are more prone to progress to Lyme carditis.

#cardiology

References:

1. Steere AC, Batsford WP, Weinberg M, et al. Lyme carditis: cardiac abnormalities of Lyme disease. Ann Intern Med 1980; 93:8. 

2. Yeung C, Baranchuk A. Diagnosis and Treatment of Lyme Carditis: JACC Review Topic of the Week. J Am Coll Cardiol. 2019 Feb 19;73(6):717-726. doi: 10.1016/j.jacc.2018.11.035. Erratum in: J Am Coll Cardiol. 2019 Nov 26;74(21):2709-2711. PMID: 30765038. 

3. Sangha O, Phillips CB, Fleischmann KE, et al. Lack of cardiac manifestations among patients with previously treated Lyme disease. Ann Intern Med 1998; 128:346. 

4. van der Linde MR, Crijns HJ, Lie KI. Transient complete AV block in Lyme disease. Electrophysiologic observations. Chest 1989; 96:219.