Prospective evaluation of the risk of bacteremia induced by transesophageal echocardiography

The incidence of bacteremia induced by transesophageal echocardiography is controversial in the Indian population. This study aimed to find out the occurrence of bacteremia following transesophageal echocardiography.

Between February 2000 and January 2001, 47 patients (26 males and 21 females) were enrolled for the study. Their ages ranged from 13 to 61 years (mean: 35 +/- 11.4 years). Patients with prosthetic valves, suspected infective endocarditis and those on antibiotics were excluded. For each procedure, two sets of blood cultures were obtained immediately before and after the procedure. For each blood culture, 10 ml of blood was evenly inoculated into brain-heart infusion broth and biphasic infusion medium and incubated for 7 days. Transesophageal echocardiography was carried out under oropharyngeal anesthesia (xylocaine gel and spray). Two blood cultures taken before the procedure were positive and excluded from the final analysis. Of the remaining 45 patients whose preprocedure blood cultures were sterile, 6 samples (13.3%) were positive after the procedure diphtheroids in 3, micrococci in 2 and aerobic spore formers in 1.

This study demonstrates that the incidence of bacteremia related to transesophageal echocardiography is not insignificant, as reported in previous studies. Though routine antibiotic prophylaxis before transesophageal echocardiography is not advocated, it should be recommended in high-risk patients such as those with prosthetic valves, multivalvular involvement or those with a past history of infective endocarditis.