Acute perimyocarditis associated with Bartonella henselae infection

Abstract

Perimyocarditis involves inflammation of the heart muscle and surrounding tissue, causing reduced left ventricular ejection fraction. Typically viral, but occasionally bacterial, this condition can arise from Bartonella henselae, a rare yet potentially serious pathogen that can lead to cardiac inflammation and subsequent heart failure. Since this bacterium is mainly associated with cat scratch disease-which is self-limiting and has a mild disease course-B. henselae's potential role in cardiac disease is underestimated. We present a mid-30s man, immunocompetent, who presented to the emergency department with acute heart failure due to B. henselae-associated perimyocarditis. Despite not recalling any scratches or bites from cats, the patient had been living with cats, which likely exposed him. This case highlights the varied clinical presentations of B. henselae-associated heart disease and underscores the importance of considering this pathogen as a potential cause of perimyocarditis, particularly in individuals with exposure to cats.

Keywords: Heart failure; Infectious diseases.

Figure 1

Presenting ECG. The presenting ECG shows sinus tachycardia, a right heart axis and an incomplete right bundle branch block. There are no clear signs of pericarditis or ischaemia. During follow-up, the ECG remained unchanged from baseline.

Figure 2

CT angiogram. Besides a mildly thickened pericardium, some pericardial effusion is visible (marked with an arrow) suggestive of pericarditis.

Figure 3

Cardiac MRI. The persistent pericardial effusion is visible as clear white surrounding the myocardium. There were no signs of wall motion abnormalities and no late myocardial enhancement. Consequently, the diagnosis of myocarditis primarily relied on biomarkers. (A) Four-chamber view. (B) Short-axis view.