The evaluation of real-time 3-dimensional transthoracic echocardiography for the preoperative functional assessment of patients with mitral valve prolapse: a comparison with 2-dimensional transesophageal echocardiography.

Objective: We sought to compare the feasibility and accuracy of transthoracic real-time 3-dimensional echocardiography (RT-3DE) with transesophageal echocardiography (TEE) for the preoperative functional assessment of patients with mitral valve prolapse.

Methods: In 44 patients with severe mitral regurgitation caused by type 2 valve dysfunction, TEE and RT-3DE were performed 24 hours before surgery and analyzed by two separate observers. TEE and RT-3DE images were acquired digitally and stored for offline analysis. The echocardiographic results were validated intraoperatively.

Results: Five patients did not have image quality suitable for analysis with RT-3DE and were excluded from analysis, leaving a sample size of 39. In total, 54 of 334 analyzed mitral valve segments were diseased. Prolapse of a single mitral valve segment was present in 25 patients and 14 patients had complex disease involving two or more segments. Sensitivity, specificity, and accuracy for TEE in identification of diseased segments were 94%, 100%, and 96%, respectively. The same values for RT-3DE were 91%, 100%, and 94%, respectively. The differences were not statistically significant. Accuracies were not significantly different according to segment location. Interobserver agreement was 92% for TEE and 88% for RT-3DE (P = nonsignificant).

Conclusions: RT-3DE is feasible with comparative accuracy to TEE for precise anatomic localization of prolapsing mitral valve segments. However, the technique is limited by poor image quality in 11% of patients.