Results of percutaneous mitral commissurotomy in patients with a left atrial appendage thrombus detected by transesophageal echocardiography.

To evaluate whether the presence of a left atrial appendage (LAA) thrombus increases the embolic risk of percutaneous mitral commissurotomy (PMC), we reviewed 240 transesophageal echocardiographic studies performed before intended PMC for mitral stenosis. We found 14 patients (5.8%) with left atrial clots, 12 located in the LAA (none detected by transthoracic echocardiography [TTE]) and two in the body of the left atrium. In the two patients who had a left atrial body thrombus, TTE did not unequivocally show the thrombus. Seven patients with an LAA thrombus underwent PMC by the double-balloon technique. The hemodynamic and echocardiographic results were comparable to those of the larger series. No embolic complications were noted either during the procedure, in the 48 hours of observation after the procedure, or at a mean follow-up of 12 months. We conclude that PMC by the double-balloon technique can be performed safely in patients with an LAA thrombus who have been given anticoagulants. Transesophageal echocardiography is still indicated before PMC because TTE is suboptimal for detection of left atrial clots.