Clinical and Echocardiographic Characteristics of Bartonella Infective Endocarditis: An 8-Year Single-Centre Experience in the United States

Background Infective endocarditis due to Bartonella species is rare. The clinical and echocardiographic characteristics are not well defined. We aimed to investigate the clinical and echocardiographic findings of Bartonella endocarditis in the contemporary era. Methods The infective endocarditis (IE) registry and echocardiographic database at our institution were retrospectively analysed to evaluate the clinical and echocardiographic features of Bartonella endocarditis. Results Between January 2008 and December 2015, there were 11 patients with Bartonella IE (0.84% among a total of 1,308 cases of definite IE): median age 54 (30-69) years, all male, 9 Caucasian, 10 had a history of cat exposure, 10 had a pre-existing valvulopathy including 6 patients with a prosthetic valve with prosthesis age range between 3 to 5 years and 1 patient with implantable cardioverter defibrillator (ICD). Bartonella henselae was responsible for all the cases. Echocardiographic evidence of IE was found in 6 of 11 patients on transthoracic echocardiography (TTE), and 6 of 8 on transoesophageal echocardiography (TEE). Bartonella IE was associated with significant valvular destruction and dysfunction on echocardiography. Nine (9) patients were managed surgically with excellent outcomes, including two patients who failed initial medical therapy. Two (2) patients who were managed medically had progression of valvular dysfunction. At a median follow-up of 6 months, there were no deaths attributable to IE or other cardiovascular causes. Conclusion In a contemporary single-centre cohort in the United States, Bartonella IE remains rare, but should be considered when pathogen could not be identified in patients with suspected IE, especially those with prosthetic valves or bicuspid aortic valve (BAV). The vast majority of patients with Bartonella IE were managed surgically with excellent outcomes.