CAN AN ECHOCARDIOGRAPHIC SCORE PREDICT WHO WILL BENEFIT CLINICALLY FROM BALLOON DILATION OF THE MITRAL-VALVE

Deciding whether a patient with sub-optimal mitral valve anatomy will benefit from percutaneous mitral valvotomy remains a demanding clinica l problem. We assessed the ability of an established echo score applie d to transoesophageal images to predict absolute increases in mitral v alve area and improvement in exercise capacity. Twenty five consecutiv e patients undergoing routine percutaneous mitral valvotomy were studi ed. Changes in exercise tolerance were measured by serial cardiorespir atory treadmill exercise testing. Before the procedure, exercise durat ion was directly related to mitral valve area (r(s) = 0.44, P < 0.05). Following percutaneous mitral valvotomy there was an increase in valv e area (0.9 +/- 0.2 to 1.4 +/- 0.3 cm(2), P < 0.0001) and repeat exerc ise testing demonstrated increases in exercise duration (470 +/- 220 t o 610 +/- 240 s, P < 0.001) and peak VO2 (12.6 +/- 4.2 to 15.1 +/- 4.5 ml/kg/min, P < 0.01). There was an inverse correlation between the ec ho score and the increase in valve area (r(s) = -0.52, P < 0.05) but n o relationship between the echo score and the increase in exercise dur ation or peak minute oxygen consumption (V-O2). These data demonstrate that a score applied to transoesophageal images echocardiographic ima ges can predict changes in mitral valve area but that the score fails to predict functional improvement for an individual patient. This sugg ests, therefore, that patients without contraindications to valvotomy whose valves have a high echo score should still be considered for val votomy as they may benefit considerably from the procedure.