Use of biplane transesophageal echocardiographic guide in radiofrequency catheter ablation of Wolff-Parkinson-White syndrome with left side Kent bundle.

: We report 2 patients with Wolff-parkinson-White Syndrome, who underwent radiofrequency (RF) catheter ablation under observation by biplane transesophageal echocardiography. One of the patients had Kent bundle in the lateral wall of the left ventricle, and the tip of the catheter could be easily confirmed with transverse views. Since perforation was observed where the valve was attached to the posterior leaflet of the mitral valve during the 39th administration of RF energy, ablation was discontinued. The other patient had Kent bundle in the posterior septum of the left ventricle. The tip of the catheter could be easily confirmed with sagittal views. Ablation was successful after the 4th administration of RF energy, but particulate contrast echoes appeared from the site of the tip of the electrode which had been used for ablation during the 4th RF delivery. When the delivery of RF energy was discontinued, the contrast echo disappeared, and a thrombus was found at the tip of the removed catheter. TEE in RF catheter ablation was helpful for confirming the site of the tip of the catheter and for early detection of complications.