Functional anatomy of mitral regurgitation - Accuracy and outcome implications of transesophageal echocardiography

OBJECTIVES This study was performed to determine the accuracy and outcome i mplications of mitral regurgitant lesions assessed by echocardiography. BACKGROUND In patients with mitral regurgitation (MR), valve repair is a ma jor incentive to early surgery and is decided on the basis of the anatomic mitral lesions. These lesions can be observed easily with transesophageal e chocardiography (TEE), but the accuracy and implications for outcome and cl inical decision-making of these observations are unknown. METHODS In 248 consecutive patients operated on for MR, the anatomic lesion s diagnosed with TEE were compared with those observed by the surgeon and t hose seen on 216 transthoracic echocardiographic (TTE) studies, and their r elationship to postoperative outcome was determined. RESULTS Compared with surgical diagnosis, the accuracy of TEE was high: 99% for cause and mechanism, presence of vegetations and prolapsed or flail se gment, and 88% for ruptured chordae. Diagnostic accuracy was higher for TEE than TTE for all end points (p < 0.001), but the difference was of low mag nitude (<10%) except for mediocre TTE imaging or flail leaflets (both p < 0 .001). The type of mitral lesions identified by TEE (floppy valve, restrict ed motion, functional lesion) were determinants of valve repairability and postoperative outcome (operative mortality and long-term survival; all p = 0.001) independent of age, gender, ejection fraction and presence of corona ry artery disease. CONCLUSIONS Transesophageal echocardiography provides a highly accurate ana tomic assessment of all types of MR lesions and has incremental diagnostic value if TTE is inconclusive. The functional anatomy of MR defined by TEE i s strongly and independently predictive of valve repairability and postoper ative outcome. Therefore, the mitral lesions assessed by echocardiography r epresent essential information for clinical decision making, particularly f or the indication of early surgery fbr MR. (J Am Coll Cardiol 1999;34:1129- 36) (C) 1999 by the American College of Cardiology.