Diagnostic and prognostic relevance of valve strands in patients with suspected infective endocarditis.

Abstract

The clinical significance and impact of valve strands, also known as Lambl's excrescences, on management in patients with suspected infective endocarditis (IE) remain unclear. The study aimed to assess the impact of the diagnosis of valve strands on the outcomes of patients investigated for suspected IE. We conducted a retrospective study at Lausanne University Hospital (2014-2024) including adult patients with a valve strand identified on cardiac imaging. Episodes were classified as IE or non-IE by a multidisciplinary Endocarditis Team (2018-2024) or by expert clinicians (2014-2017). One-year outcomes included recurrence of bacteremia/candidemia or IE by the same microorganism. Among 305 episodes with valve strands, 101 (33%) were diagnosed as IE by the Endocarditis Team or expert clinicians. Among the 204 episodes without IE, 165 (81%) had bacteremia/candidemia. Valve strands were identified by transthoracic echocardiography in 141 (50%) out of 282 episodes, and by transesophageal echocardiography in 191 (79%) out of 244 episodes. Among the 257 episodes with bacteremia/candidemia, recurrence of bacteremia/candidemia caused by the same microorganism within one year occurred in 7/92 (8%) among those with IE and 11/165 (7%) among those without (P=0.971). Recurrence of IE due to the same microorganism within one year was significantly more frequent among episodes with IE compared to those without (6/92; 7% versus 2/165; 1%; P=0.029). Most valve strands detected in patients with suspected IE do not represent infectious lesions. Careful evaluation by expert cardiologists and multidisciplinary discussion can safely differentiate valve strands from vegetations, reducing unnecessary treatment.