Lyme Carditis: Cardiac Abnormalities of Lyme Disease

Abstract

In 20 patients, mostly young adult men, with cardiac involvement of Lyme disease, the commonest abnormality (18 patients) was fluctuating degrees of atrioventricular block; 8 developed complete heart block. Thirteen patients had evidence of more diffuse cardiac involvement: ECG changes compatible with acute myopericarditis (11 patients), radionuclide evidence of mild left ventricular dysfunction (5 of 12 patients tested) or frank cardiomegaly (1 patient). Heart involvement was usually preceded by erythema chronicum migrans and sometimes accompanied by meningoencephalitis, facial palsy, arthritis, elevated serum IgM levels or cryoglobulins containing IgM. The duration of cardiac involvement was usually brief (3 days-6 wk). The clinical picture in these patients has similarities to acute rheumatic fever but in Lyme disease complete heart block may be more common, myopericardial involvement tends to be milder and valves seem not to be affected.