Transoesophageal echocardiographic assessment of mitral valve commissural morphology predicts outcome after balloon mitral valvotomy

Abstract

Objective: To investigate the value of transoesophageal echocardiography in the assessment of commissural morphology and prediction of outcome after balloon mitral valvotomy (BMV). Design: Prospective study. Setting: Tertiary cardiac referral centre. Patients: 72 consecutive patients (mean age 61.3 years, range 38-89 years) referred for BMV. Interventions: Transoesophageal echocardiography was performed immediately before BMV and the mitral commissures were scanned systematically. Anterolateral and posteromedial commissures were scored individually according to whether non-calcified fusion was absent (0), partial (1), or extensive (2). Calcified commissures usually resist splitting and scored 0. Scores for each commissure were combined giving an overall commissure score for each valve of 0-4, higher scores reflecting increased likelihood of commissural splitting. Valve anatomy was also graded by the method of Wilkins et al, which does not include commissural assessment. Main outcome measures: Patients were divided into outcome groups: A (good) and B (suboptimal). "Good" was defined as final valve area > 1.5 cm 2 with a > 25% increase in area and absence of severe mitral regurgitation judged by echocardiography. Results: Valve area increased from a mean (SD) of 1.1 (0.28) cm2 to 1.8 (0.46) cm2. Commissure scores were higher in group A than in group B (p < 0.01), scores ≥ 2 predicting a good outcome with positive and negative accuracy of 67% and 82%, respectively (p < 0.001). Commissure score was the strongest independent predictor of outcome. Conclusion: Transoesophageal echocardiographic assessment of commissural morphology predicts outcome after BMV, adding significantly to the Wilkins score.