CC BY-NC-ND 4.0 · THORAC CARDIOV SURG Reports 2018; 07(01): e35
DOI: 10.1055/s-0038-1660808
Editorial Commentary
Georg Thieme Verlag KG Stuttgart · New York

“If You Hear Hoof Beats, Think Horses, Not Zebras”

Andreas Boening
1  Justus-Liebig University, Giessen, Germany
Heiko Burger
2  Department of Cardiovascular Surgery, Kerckhoff-Clinic, Bad Nauheim, Germany
› Author Affiliations
Further Information

Publication History

02 February 2018

21 March 2018

Publication Date:
05 July 2018 (online)

Primary Cardiac B-Non-Hodgkin Lymphoma Disguised as a Pacemaker Endocarditis

The very interesting case report by Fleissner et al[1] represents an example of a diagnostic mistake where a diagnosis of a common disease was made, but a rare one was found. The authors are to be congratulated on their courage to report this “negative” case, because learning does not always come from success, but also from mistakes. If mistakes are not reported, learning from them is impossible. Fortunately, in this case the patient received an adequate therapy and had a comparatively good outcome.

Looking at the echocardiography video retrospectively, one easily recognizes that it does not show the typical features of a lead endocarditis. As the authors comment, a thoracic computed tomography scan would have been appropriate, but was not performed. In this case, although the ultrasound picture does not show a clear pacemaker lead vegetation, the clinical picture of the patient together with the higher incidence of lead endocarditis compared with a cardiac tumor led the authors to pursue the diagnosis of a lead infection. The recommendations for the management of pacemaker lead infections from 2010,[2] and the Heart Rhythm Society Expert Consensus Statement on cardiovascular implantable electronic device lead management and extraction from 2017,[3] unfortunately not cited in the case report, show a class I indication for lead removal in cases of definitive lead endocarditis.

What is to be learned here? It seems that—although “common is common and rare is rare” is a valid medical principle—sometimes the sound of hoof beats should lead to consider the possibility of zebras, not only of horses.