Table 4.
Key Studies Evaluating the Role of Transesophageal Echocardiography in Patients With Staphylococcus aureus Bacteremia
| Study | Study Period | Study Design | No. of Patients | Study Findings/Conclusion | IE (%) | Comments |
|---|---|---|---|---|---|---|
| Joseph et al [25] | 2006–2011 | Retrospective study of all cases of SAB | 306 | Patients with underlying prosthetic intracardiac material were higher risk of IE; authors concluded the cardiac imaging should be prioritized to high-risk patients | 10.1 | Of 668 eligible patients with SAB, only 82 (12.7%) underwent TEE |
| Khatib and Sharma [24] | 2002–2009 | Included patients from 3 previous prospective observational studies (2002–2003, 2005–2006, 2008–2009) | 379 | Authors concluded that TEE is dispensable in patients with uncomplicated SAB | 7.3 | 498 of 877 eligible patients (57%) did not undergo echocardiography (TTE or TEE) and were excluded; of 877 eligible patients with SAB, only 177 (20%) underwent TEE |
| Incani et al [7] | 1998–2006 | Retrospective study of all adult patients who were hospitalized with SAB and underwent TEE | 144 | 46% of IE patients were not suspected to have IE based on clinical findings alone; authors concluded that TEE is indicated in all patients with SAB as clinical findings are not sensitive | 29 | 83% of eligible patients underwent TEE and were included in the study |
| Rasmussen et al [28] | 2009–2010 | Prospective observational study of SAB patients | 244 | Noted high rates of IE; clinical symptoms and findings were noted to be insensitive and nonspecific; authors concluded that echocardiography should always be considered in early evaluation of patients with SAB | 22 | Limited by selection bias; 92 eligible patients (27%) did not undergo echocardiography (TTE or TEE) and were excluded; 62% of study patients underwent TEE |
| Kaasch et al [23] | 1994–2009 | Post hoc analysis of 2 prospective SAB cohorts (INSTINCT and SABG) | 736 nosocomial | TEE may not be required in a subset of low-risk nosocomial SAB patients identified by using a simple criteria set | 4.3 (INSTINCT) 9.3 (SABG) | Only 18.5% of INSTINCT and 27.6% of SABG cohorts underwent TEE; included only nosocomial SAB |
| Van Hal et al [29] | 1996–2000 | Retrospective study of patients who underwent both TTE and TEE | 125 | TEE may not be required in a subgroup of low-risk SAB patients if TTE is normal and there are no embolic signs | 18 | Of 808 eligible patients with SAB, 641 (79%) had no TEE and were excluded; limited by sampling bias; excluded patients with prosthetic valves, annuloplasty rings, implantable cardioverter defibrillator, or permanent pacemaker |
| Abraham et al [15] | 1999–2002 | Retrospective review of SAB cases who were referred for either TTE or TEE | 104 | Noted high rates of endocarditis; SAB patients should be aggressively evaluated for endocarditis | 31.7 | Limited by referral bias as only patients with high pretest clinical probability were likely referred for echocardiography |
| Fowler et al [8] | 1994–1996 | Prospective study of SAB patients who underwent both TTE and TEE | 103 | Only 7% of patients had clinical evidence of IE; sensitivity of TTE was only 32%; TEE had 100% sensitivity as none met Duke criteria for definite IE without positive TEE; authors concluded that TEE should be considered in early evaluation of patients with SAB | 25.2 | Only 59% of eligible patients with SAB underwent both TTE and TEE; limited by sampling bias as physicians tended to refer patients with higher likelihood of IE for TEE |
Abbreviations: IE, infective endocarditis; INSTINCT, invasive Staphylococcus aureus infection cohort; SAB, Staphylococcus aureus bacteremia; SABG, Staphylococcus aureus bacteremia group; TEE, transesophageal echocardiogram; TTE, transthoracic echocardiogram.