Contrast-enhanced Ultrasound Evaluation of Splenic Embolization in Patients with Definite Left-Sided Infective Endocarditis

The purpose of the study described here was to prospectively evaluate the significance of embolization of the spleen in patients with definite left-sided infective endocarditis (IE) using contrast-enhanced ultrasound (CEUS). From March through October 2012, 6 consecutive patients (4 females and 2 males, aged 27 to 83 years) with definite left-sided IE according to the revised Duke criteria were enrolled. All patients gave informed written consent, and the study was performed in conformity with the ethical guidelines of the Declaration of Helsinki. All patients underwent CEUS of the spleen within 1 week of the definite diagnosis of IE. A blood pool second-generation contrast agent and an ultrasound machine with contrast harmonic imaging technology were used for CEUS. Fifteen consecutive patients (7 females and 8 males, aged 39 to 88 years) who underwent CEUS from October through November 2012 for the study of focal liver lesions constituted the control group. The number of patients did not permit statistical analysis. Splenic CEUS revealed infarctions in 5 patients and an infarcted area in the only patient with negative echocardiography. All splenic CEUS procedures in the control group were negative. In this study, CEUS of the spleen, a repeatable and low-cost imaging technique, easily allowed bedside detection of asymptomatic and even tiny infarctions, and revealed a high rate of embolization in patients with definite left-sided IE. Indeed, splenic CEUS, if applied to the workup of patients with suspect IE, has the potential to accelerate or upgrade the diagnosis itself.