Cardiac Magnetic Resonance Imaging in Lyme Carditis-A Case Series and Review of Literature

Abstract

Lyme carditis is an uncommon but potentially fatal manifestation of early disseminated Lyme disease. Timely diagnosis poses a clinical challenge due to the highly variable and non-specific symptomatology that can be easily overlooked, as well as the limited availability of specific and non-invasive diagnostic tests for assessing cardiac involvement. While cardiac magnetic resonance (CMR) imaging is the standard imaging modality for diagnosing various etiologies of cardiomyopathy, its application in Lyme carditis remains understudied. In this study, we present two cases of CMR-proven Lyme carditis and provide a comprehensive review of the existing literature on the use of CMR in this condition.

Keywords: Borrelia; Lyme carditis; Lyme disease; MRI; cardiac; myocarditis.

Figure 1

Erythema chronicum migrans rash located on the patient’s right abdomen. Image obtained one week prior to emergency department presentation at an urgent care center.

Figure 2

Cardiac magnetic resonance imaging findings. Top images demonstrate the presence of late gadolinium enhancement in lateral segments (white arrows). Bottom images demonstrate corresponding acute inflammation in basal lateral segments.

Figure 3

Mildly reduced left ventricular global longitudinal strain measured by cardiac magnetic resonance imaging. (A) depicts cardiac magnetic resonance feature tracking global longitudinal strain in four chamber view; (B) depicts left ventricular global longitudinal strain (y-axis) over time during cardiac cycle (x-axis). The peak negative value (–13.2%) indicates a reduced maximal degree of myocardial shortening during systole, suggesting impaired left ventricular systolic function.

Figure 4

Electrocardiogram findings in Lyme carditis. The baseline ECG (A) was performed at presentation to the emergency department and shows 2:1 AV block (Lead II). Follow-up ECG (B) was performed after a three-week course of oral doxycycline and demonstrates resolution to normal sinus rhythm with borderline first-degree AV block.

Figure 5

(A) (long-axis view) and (B) (short-axis view) demonstrate cardiac magnetic resonance imaging with subepicardial late gadolinium enhancement (orange arrows) in the basal anteroseptal and inferolateral segments. (C) depicts cardiac magnetic resonance feature tracking global longitudinal strain in four chamber view; (D) depicts left ventricular global longitudinal strain (y-axis) over time during cardiac cycle (x-axis). The peak negative value (–15.0%) indicates a reduced maximal degree of myocardial shortening during systole, suggesting impaired left ventricular systolic function.

Figure 6

Lyme carditis pathogenesis and the diagnostic role of cardiac imaging techniques. After entering the human host through the bite of the Ixodes tick, Borrelia spirochetes demonstrate tropism for cardiac tissue in the AV nodal region, precipitating characteristic conduction disturbances and myocarditis. Cardiac diagnostic modalities, including electrocardiogram, echocardiogram, and cardiac magnetic resonance imaging, can help characterize the extent of cardiac involvement and inform clinical decision-making. Image created in BioRender [24].