Catheter ablation involving the left ventricle increases risk of damage to the mitral valve or chordae tendineae which can lead to acute mitral regurgitation. This may place the patient in danger whether using a transaortic approach or transseptal approach. Here we report a case diagnosed as ablation catheter entrapment by chordae of the mitral valve during radiofrequency ablation monitored by periprocedural transesophageal echocardiogram. The entrapped ablation catheter was smoothly removed by open surgery and no damage to the mitral valve complex was detected. Removal of an entrapped catheter by blinded traction is associated with damage to the mitral valve complex.