First experience with microprobe transoesophageal echocardiography in non-sedated adults undergoing atrial fibrillation ablation: feasibility study and comparison with intracardiac echocardiography

Aims Imaging of the left atrium (LA) is mandatory during catheter ablation of atrial fibrillation (AF) and may be achieved by echocardiography. The aim of the present study was to assess the feasibility of using a recently released transoesophageal echocardiography (TEE) microprobe (micro-TEE) in non-sedated adult patients undergoing AF ablation and to directly compare this new technique with intracardiac echocardiography (ICE). Methods and results The study group consisted of 12 consecutive patients (8 males, mean age 49 +/- 14 years) who underwent first radio-frequency AF ablation. All patients underwent standard TEE, computed tomography, intraprocedural micro-TEE, and ICE. The easiness of introducing the microprobe in the supine position in non-sedated patients in the electrophysiology laboratory, its tolerability, and quality of obtained images were assessed using a five-point scale. There were no problems with microprobe introduction and obtaining images for a mean of 54 +/- 17 min. The microprobe was significantly better tolerated than the standard TEE probe (4.3 +/- 0.5 vs. 3.4 +/- 0.6 points, P < 0.01). The micro-TEE was scored as significantly better than ICE in the assessment of the LA and LA appendage (LAA) anatomy and function. Both techniques were very useful in guiding transseptal puncture, although micro-TEE images were ranked higher by an echocardiographer than by an electrophysiologist (tenting 4.8 +/- 0.6 vs. 4.0 +/- 0.6 points, P < 0.01), whereas ICE images were ranked equally excellent by both observers. Conclusion In non-sedated patients undergoing AF ablation, the micro-TEE can be used for the assessment of the LA, LAA, and pulmonary veins anatomy as well as the guidance of transseptal puncture.