Real‐World Diagnostic Performance of Repeat Transthoracic Echocardiography Within a Multimodality Imaging Approach in Patients With Suspected Infective Endocarditis

Background Echocardiography is central to the diagnosis of infective endocarditis (IE). Although guidelines recommend repeating echocardiography when clinical suspicion persists despite negative or inconclusive findings, the diagnostic value of repeating transthoracic echocardiography (TTE) remains uncertain. The aim was to evaluate the diagnostic performance of repeat TTE in the diagnosis of IE among patients with suspected IE. Methods This retrospective study conducted at Lausanne University Hospital (2015–2024) including adult patients with suspected IE who underwent 2 TTEs within 21 days. IE was classified according to the 2023 Duke‐ International Society for Cardiovascular Infectious Diseases criteria. Results A total of 503 episodes were included, of which 254 (50%) were diagnosed as IE. The second TTE was performed within 8 days from first TTE (interquartile range, 5–13 days). The second TTE identified new vegetations in 34 (7%) episodes and new paravalvular complications in 17 (3%) episodes. Sensitivity for detecting vegetations increased from 47% (95% CI, 39%–56%) for the first TTE to 57% (95% CI, 48%–65%) for the second. By excluding the results of cardiac imaging modalities other than TTE, the sensitivity of the second TTE for diagnosing IE was higher (45% [95% CI, 38%–51%]), compared with 34% (95% CI, 28%–41%) for the first TTE; the second TTE led to reclassification from possible to definite IE in 7 (1%) of cases. Conclusions Repeat TTE modestly improved typical IE lesion detection; however, within a multimodality imaging strategy, its incremental diagnostic contribution was limited. These results suggest that repeated TTE alone is unlikely to substantially alter diagnosis in most patients, supporting the use of complementary imaging when suspicion of IE remains high.