Introduction and aims: Transthoracic echocardiography is a technique with high specificity but low sensitivity in the diagnosis of valvular vegetations and infectious endocarditis complications. Recent reports have shown the transesophageal technique to be more sensitive. The aim of this study was to assess the comparative diagnostic roles of transthoracic and transesophageal echocardiography in infectious endocarditis.
Methods: Eighty-eight patients with infectious endocarditis (native valve in 71 and prosthesis in 17) were studied. All underwent transthoracic echocardiogram followed by transesophageal study to detect vegetations and possible complications, particularly paravalvular abscesses.
Results: Transthoracic echocardiogram diagnosed vegetations in 33 (46%) of the 71 native valve endocarditis, whereas these were detected by transesophageal study in 67 (94%). In 23 patients vegetations were surgically confirmed. Transthoracic echocardiography failed to diagnose vegetations in any of the prosthetic endocarditis, whereas they were detected by transesophageal study in 11 of the 17 cases (65%). Of the 9 patients who underwent surgery in the acute phase, 5 presented vegetations on transesophageal study which were confirmed at surgery. Transesophageal echocardiography diagnosed 14 abscesses: 11 aortic peri-annular and 3 in the interfibrous. Echocardiography only detected 1 of the peri-annular aortic abscesses. All patients with peri-annular abscess underwent surgery. Transesophageal echocardiography was also more effective than transthoracic in the diagnosis of other complications: 15 vs 4 chordae tendineae mitral valve rupture and 18 vs 13 aortic valve disruption.
Conclusions: Transesophageal echocardiography is more effective than transthoracic echocardiography in the diagnosis of infectious endocarditis and its complications and would therefore be indicated in all cases of absence of vegetations on transthoracic echocardiography and clinical suspicion of endocarditis. Transesophageal echocardiography could be indicated in all cases of clinically suspected aortic endocarditis to rule out peri-annular abscesses.