Gallium avid Lyme myocarditis

Lyme carditis

Cardiovascular manifestations of Lyme disease were first reported nearly 30 years ago. This article describes Lyme carditis, its epidemiology, pathophysiology, methods of diagnosis, and treatment options.

[Lyme arthritis, Lyme carditis and other presentations potentially associated to Lyme disease]

Lyme disease or Lyme borreliosis is the most common tick-transmitted disease in the Northern hemisphere and is caused by Borrelia burgdorferi spirochetes. Lyme disease commonly begins with a characteristic skin lesion, erythema migrans. Weeks or months later, the patients may have neurologic, joint, or cardiac abnormalities. Some patients may still present persistent deep fatigue and various unspecific symptoms after standard courses of antibiotic treatment for Lyme disease. This constellation of symptoms has been variously referred to as "chronic Lyme disease", or "post-Lyme disease syndrome". The first French National Consensus Conference on Lyme Disease was the reason to review all aspects of articular and cardiac manifestations of Lyme disease after a synthesis of recent literature. The involvement of Borrelia species in chronic Lyme disease and other pathologies is discussed.

Cardiac manifestations of Lyme disease

Lyme disease is a vector-borne illness that can affect numerous organ systems during the early disseminated phase, including the heart. The clinical course of Lyme carditis is usually benign with most patients recovering completely. In rare instances, death from Lyme carditis has been reported. The cardinal manifestation of Lyme carditis is conduction system disease, which generally is self-limited. Heart block occurs usually at the level of the atrioventricular node but often is unresponsive to atropine sulfate. Temporary pacing may be necessary in more than 30% of patients, but permanent heart block rarely develops. Myocardial and pericardial involvement can occur but generally is mild and self-limited. Diagnosis is made by associating the clinical and historical features of borreliosis, such as previous tick bite, EM, or neurologic involvement, with electrocardiographic abnormalities and symptoms such as chest pain, palpitations, syncope, and dyspnea. Serologic studies and endomyocardial biopsy can support the diagnosis in the correct clinical setting, and MR imaging, echocardiography, and gallium scanning have utility in selected circumstances. No treatment has been shown clearly to attenuate or prevent the development of Lyme carditis, but mild carditis generally is treated with oral antibiotics and severe carditis with intravenous antibiotics in an effort to eradicate the infection and prevent late complications of Lyme disease. There is conflicting evidence regarding the role that B. burgdorferi plays in the development and progression of chronic congestive heart failure. Because of the significant false-positive ELISA rate in this population and the unclear benefit of antibiotic therapy, confirmatory Western blot analysis is recommended. Routine therapy and screening of patients with idiopathic dilated cardiomyopathy is of limited utility and should be reserved for patients with clear history of antecedent Lyme disease or tick bite.

SLE myocarditis. Detection by Ga-67 citrate scintigraphy

Cardiac uptake of Ga-67 in myocarditis has been described in association with a number of disease entities. However, there are no reports in the current literature describing Ga-67 uptake in myocarditis due to systemic lupus erythematosus, a disease that often involves the heart. The authors present the case of a patient with a long history of systemic lupus erythematosus in whom new ECG changes and left ventricular wall motion abnormality developed, and who demonstrated significant global myocardial uptake on Ga-67 scintigraphy. Other etiologies including myocardial infarction, epicardial coronary disease, pericarditis, endocarditis, dilated cardiomyopathy, and viral infection were excluded during extensive work-up.

Cardiovascular manifestations of Lyme disease

Although the cardiac manifestations of Lyme disease may be diverse, in general they are treatable with currently available therapies. A high index of suspicion is required to make a diagnosis, especially for patients who may lack a suggestive history of tick exposure or residence in an endemic region. Lyme disease-related heart block may require pacemaker insertion and supportive care. The efficacy of antibiotics in the therapy of acute and chronic cardiac Lyme disease will require further study. Serologic testing and cardiac histopathology are the most precise methods of diagnosis. There is a need to develop more sensitive and specific diagnostic tests for Lyme disease and for Lyme carditis in particular.

Range of atrioventricular conduction disturbances in Lyme borreliosis: a report of four cases and review of other published reports

Four patients with Lyme borreliosis had atrioventricular conduction disturbances. All four were positive for specific antibodies against Borrelia burgdorferi measured by indirect immunofluorescence tests. Biopsy specimens, which were obtained in three patients, showed band-like infiltrates of plasma cells and lymphocytes in the endocardium. There was diffuse infiltration of the interstitium of the myocardium by lymphocytes, plasma cells, and macrophages. In two patients single fibre necrosis was seen in the myocardium. Biopsy specimens of the heart showed spirochetes in all three patients and serial sections stained by the Bosma-Steiner technique showed that they resembled Borrelia burgdorferi. At follow up one patient had persistent complete atrioventricular block, despite treatment with antibiotics and corticosteroid, and a permanent pacemaker was implanted.