Transesophageal Echocardiography in Candidates for Percutaneous Balloon Mitral Valvuloplasty

Prior to percutaneous balloon mitral valvuloplasty (PBMV), mitral valve morphology and the presence of left atrial thrombi are usually evaluated by transthoracic two-dimensional and Doppler echocardiography (TTE). This study analyzes the impact of transesophageal echocardiography (TEE) in addition to TTE on the selection of candidates considered for PBMV for mitral stenosis. Seventy-five patients with severe mitral stenosis who were considered as appropriate candidates for PBMV based on TTE findings were studied. In 19 (25%) patients, TEE revealed findings that were essential for PBMV but were missed by TTE: left atrial thrombi (n = 14; including 13 in left atrial appendage), right atrial thrombus (n = 1), incomplete cor triatriatum (n = 1) and mitral valve vegetation (n = 1). In two other patients, a left atrial thrombus had been suspected by TTE but could be excluded by TEE. TEE and TTE revealed similar scores of thickening, calcification, and mobility of the mitral valve. Compared to TTE, thickening of the subvalvular apparatus was graded lower using horizontal plane TEE due to shadowing by the mitral valve (echo score 1.8 ± 0.8 vs 1.4 ± 0.7; P < 0.05) whereas results from longitudinal plane TEE were similar to TTE findings. The data show that due to the high prevalence of left atrial thrombi, TEE should be performed in addition to TTE in all patients prior to PBMV.