The recognition of systemic thromboembolism as a significant potential complication of cardioversion during interventional cardiology procedures in patients with AF has stimulated interest in the clinical evaluation of catheter based intra cardiac echocardiography (ICE). Initial experience with intra cardiac phased -array imaging has demonstrated the efficacy and feasibility of this technology for intracardiac application and its capability in high resolution imaging of endocardial structures. (5) In the recent times, the utility of this imaging modality in various interventional procedures has been investigated and its effectiveness in visualizing left atrial thrombi during ablative procedures has been demonstrated in observational studies. (6 -11) However, a prospective multicenter comparative study of these two imaging techniques is unavailable. Should ICE provide comparable imaging capabilities to TEE, the value of ICE guided cardioversion during invasive procedures can also then be systematically studied during a prospective multicenter clinical study.