A Scenario-Based Survey of Expert Echocardiography Recommendations for Patients With Staphylococcus aureus Bacteremia at Varying Risk for Endocarditis

Question Which echocardiography strategies do expert clinicians recommend for patients with Staphylococcus aureus bacteremia at varying risk for endocarditis? Findings In this survey study of 656 respondents from 24 countries, the echocardiography recommendations of expert clinicians for a variety of S aureus bacteremia scenarios were closely aligned to the burden of endocarditis risk factors. Substantial disagreement was seen between respondents as to the single best echocardiography strategy, particularly for scenarios with a low risk of infective endocarditis. Meaning Experts demonstrate active and precise risk stratification when recommending echocardiography strategies for patients with S aureus bacteremia, but disagreement exists as to the appropriate investigation of lower-risk cases. This survey study assesses clinicians' preferred echocardiography strategies for a variety of hypothetical scenarios involving patients with Staphylococcus aureus bacteremia and various combinations of risk factors for endocarditis. Importance Echocardiography to detect infective endocarditis is regarded as a key quality indicator in the care of patients with Staphylococcus aureus bacteremia, but its application varies markedly between reported series. Understanding the reasons for this variation in practice is important to improve the use of this investigation. Objective To identify expert clinicians' preferred echocardiography strategy for a variety of S aureus bacteremia scenarios in a hypothetical setting free from extrinsic constraints. Design, Setting, and Participants Anonymous web-based survey study comprising 50 text-based scenarios describing patients with S aureus bacteremia and various combinations of risk factors for endocarditis. Other variables included patient age and the presence of an extracardiac focus of infection warranting prolonged treatment. The survey was emailed to participants between September 2018 and March 2019. Each respondent was asked to recommend 1 of 6 echocardiography strategies for up to 8 randomly selected scenarios. Respondents were primarily infectious diseases physicians, and more than half reported an annual caseload of more than 20 cases of S aureus bacteremia. Main Outcomes and Measures The proportion of respondents selecting each of the 6 echocardiography strategies was calculated alongside Wilson score confidence intervals. Modified Fleiss kappa statistics were used to described interrespondent variability. Generalized estimating equations were used to assess the associations between respondent- and scenario-level variables and the recommendation of an echocardiography strategy with a low negative likelihood ratio for infective endocarditis (ie, a highly exclusionary strategy). Results A total of 656 respondents from 24 countries provided 4837 echocardiography recommendations across the 50 scenarios. Echocardiography recommendations were associated with scenarios' burden of endocarditis risk (multivariate odds ratio per point of the VIRSTA score, 1.4; 95% CI, 1.4-1.5; P < .001). Poor interrespondent agreement was seen across all scenarios (modified Fleiss kappa, 0.06; 95% CI, 0.05-0.07) but was most notable for scenarios with a lower risk of endocarditis (modified Fleiss kappa, 0.04; 95% CI, 0.03-0.05). The presence of an extracardiac focus of infection was also associated with the choice of echocardiography strategy (odds ratio for highly exclusionary strategy, 0.51; 95% CI, 0.45-0.58). Respondent location in continental Europe was associated with recommendations in favor of a highly exclusionary strategy (odds ratio, 1.8; 95% CI, 1.3-2.5) compared with location in Australia or New Zealand. Conclusions and Relevance In this study, expert clinicians demonstrated active stratification by risk of endocarditis when making echocardiography recommendations for hypothetical patients with S aureus bacteremia. Substantial disagreement existed as to whether patients at lower risk of endocarditis should undergo transesophageal echocardiography-based echocardiography strategies.