Multiplane transoesophageal echocardiography and morphology of regurgitant mitral valves in surgical repair

BACKGROUND: An essential step in the surgical management of patients with mitral regurgitation, is a thorough understanding of the pathophysiological mechanism. This information can be obtained by multiplane transoesophageal echocardiography which displays all the components of the incompetent valve. METHODS AND RESULTS: Forty-nine patients were scanned intra-operatively by multiplane transoesophageal echocardiography, and findings compared with those at visual inspection during surgery. The pre-operative diagnosis was prolapse of the anterior mitral leaflet in nine patients (sensitivity 100%, specificity 95%), prolapse of the posterior leaflet in 17 patients (sensitivity 100%, specificity 94%) and prolapse of both leaflets in eight patients (sensitivity 87%, specificity 100%). In 11 patients annular dilatation with no abnormalities in mitral leaflet closure or motion was diagnosed (sensitivity 73%, specificity 100%). Two patients had a false-positive diagnosis of prolapse of the anterior leaflet, two others on the posterior leaflet. A prolapse of both leaflets was overlooked in one patient. Multiplane transoesophageal echocardiography scanned the mitral valve, disclosing the extent of pathology along the closure line of leaflets in 88% of patients with mitral valve prolapse. The antero-posterior diameter of the mitral annulus was measured: a diameter over 35 mm indicated annular dilatation. Using this criterion, sensitivity was 89% and specificity 100%. CONCLUSIONS: Multiplane transoesophageal echocardiography enabled components of the mitral valve to be examined systematically, and provided important information on the pathophysiological mechanism of mitral regurgitation before surgical repair. The method also allowed the surgical outcome to be assessed, offering the possibility of optimal repair.