Has transesophageal echocardiography changed the approach to patients with suspected or known infective endocarditis?

Perioperative transoesophageal echocardiography

New technologies are being introduced every day in the perioperative setting and perioperative practitioners will need to become increasingly familiar with transoesophageal echocardiography (TOE). TOE is used as a diagnostic tool during cardiac surgery in the operating theatre to direct the surgical procedure and to detect acute complications. TOE is also used to monitor cardiac function in patients undergoing non-cardiac surgery and in the intensive care unit (ICU) (Figure 1). The use of TOE is increasing in the cardiac catheterisation laboratory for percutaneous transcatheter procedures such as patent foramen ovale (PFO) closure, atrial septal defect (ASD) closure, aortic and mitral valvuloplasty, aortic valve implantation and mitral valve repair. Since the oesophagus is located directly behind the heart, TOE provides better image quality than transthoracic imaging for the assessment of posterior cardiac structures such as the mitral valve, left atrium and pulmonary veins.

Limitations and discrepancies of transthoracic and transoesophageal echocardiography compared with surgical findings in patients submitted to surgery for complications of infective endocarditis

OBJECTIVE

Transoesophageal echocardiography (TEE) is recognized to be superior to transthoracic echocardiography (TTE) in evaluating complications of infective endocarditis (IE). The aim of this study was to compare results from TTE and TEE with surgical findings, and to assess limitations and discrepancies of TEE as compared with surgical findings.

METHODS

A retrospective analysis was carried out in 63 consecutive patients undergoing surgical intervention for IE-related complications. All patients were submitted to TTE and TEE before surgery. Clinical, anaesthesiological and surgical data were reviewed for all patients as well as the TTE and TEE examinations recorded on S-VHS videotape. Patients were divided into two groups according to the time elapsed from TEE to surgery (> 72 h in group A and < 72 h in group B).

RESULTS

The study population included 44 patients with native valve endocarditis and 19 patients with prosthetic valve endocarditis for a total of 76 affected valves (54 native and 22 prosthetic valves). No significant differences were observed between groups in number of patients (31 vs. 32; P = NS), of native valves (29 vs. 27; P = NS), and of prosthetic valves (10 vs. 12; P = NS). Discrepancies between TEE and surgical findings were found in 14 cases (11/31 in group A vs. 3/32 in group B; P = 0.01).

CONCLUSIONS

Time between TEE and surgery seems to be an important factor affecting comparison. Lesion characteristics appear to be more precise and concordant with surgical findings the shorter the time elapsed from TEE to surgery. Changes resulting from disease progression require repeat TEE evaluation prior to surgical intervention for IE-related complications. This could be useful in providing the surgeon with a more accurate definition of valvular lesions for optimal planning of intervention.