Intracardiac ultrasound

This chapter describes the uses and advantages of intracardiac ultrasound (ICUS). The current longitudinal phased array, with variable ultrasound frequency, ICUS can provide comparable images to transesophageal echocardiography especially of the left heart, the interatrial septum, the valves, and the pulmonary veins (PVs). With the constantly increasing complexity of left-sided catheter-based ablative procedures, it has become mandatory that electrophysiologists be experts in the technique of transseptal catheterization. The advent of ICUS has vastly enhanced the safety and success of transseptal access during electrophysiological procedures and can supplant other traditional imaging modalities like fluoroscopy. After successful transseptal procedure, a circumferential mapping catheter is typically deployed at or near the ostium of the targeted PV, used for mapping, remapping, and as guidance for ablation. This catheter's characteristic structure is easily visualized and its relationship to the ostium of the PVs could be continuously assessed by ICUS.