[Usefulness of intracardiac echocardiography for guidance of transseptal puncture procedure].

The clinical usefulness of intracardiac echocardiography (ICE) for the guidance of transseptal puncture procedure during percutaneous left heart bypass support (PLHBS) and percutaneous transvenous mitral commissurotomy (PTMC) was investigated to replace intraoperative transesophageal echocardiography monitoring which requires mild sedation and causes patient discomfort. The ICE procedure was assessed in 3 patients with PLHBS and 18 with PTMC using a 10 MHz rotating 8 French probe system especially developed for the purpose. Transseptal puncture procedure was observed by intraoperative ICE monitoring in the right atrium. The ICE images showed the transseptal puncture (Brokenbrough) needle as a point casting an acoustic shadow. By moving the ICE probe up and down, the excursion of the needle and its approach to the septal wall could be clearly observed. If the puncture needle is forced into the intra-atrial septum, the septal wall was clearly observed to protrude into the left atrium (tent-formation). In a tent-formation the puncture site could be determined by ICE alone. Intracardiac echocardiography guidance was useful and may improve the safety and reliability of the transseptal puncture procedure in PLHBS and PTMC.