A PROSPECTIVE-STUDY OF THE SEROPREVALENCE OF BORRELIA-BURGDORFERI INFECTION IN PATIENTS WITH SEVERE HEART-FAILURE

Lyme disease, caused by the spirochete Borrelia burgdorferi, can disseminate from the initial cutaneous infection to involve the heart, nervous system, and joints. Lyme disease has been associated with cardiac involvement in up to 8% of patients.(1) Although the most common cardiac complications are conduction system disturbances, pericarditis and myocarditis have also been reported.(2) In addition, 1 study reported lower resting heart rates in asymptomatic B. burgdorferi seropositive persons than in seronegative persons.(3) B. burgdorferi causes myocarditis in both C3H mice(4) and in guinea pigs(5) and has been cultivated from an endomyocardial biopsy of a patient with cardiomyopathy and serologic evidence of exposure to B. burgdorferi.(6) A European group reported that ceftriaxone therapy was followed by improvement in left ventricular ejection fraction in 8 of 9 B. burgdorferi seropositive patients with dilated cardiomyopathy.(7) These findings raise the possibility that B. burgdorferi may be an important etiologic agent of otherwise unexplained cardiomyopathy in endemic areas. The University of Minnesota is a referral center for patients with severe cardiomyopathy and is located in a region where Lyme disease is endemic. To evaluate the possible role of B. burgdorferi as an etiologic agent in chronic severe heart failure, we prospectively studied 175 consecutive patients referred to the University of Minnesota for evaluation of heart failure and possible cardiac transplantation. We hypothesized that if B. burgdorferi was an etiologic agent among our heart failure patients with idiopathic cardiomyopathy, they should have higher seropositivity rates than patients with ischemic heart disease or healthy controls.