宮本 直政, 許 俊鋭, 元山 猛, 今福 博司　, 村松 俊裕, 松村 誠, 尾本 良三, 土肥 豊

Naomasa MIYAMOTO, Shunei KYO, Takeshi MOTOYAMA, Hiroshi IMAFUKU, Toshihiro MURAMATSU, Makoto MATSUMURA , Ryozo OMOTO, Yutaka DOHI

埼玉医科大学心臓センター

Saitama Heart Institute, Saitama Medical School

キーワード : Intracardiac echocardiography , Transesophageal echocardiography, Percutaneous transvenous mitral commissurotomy, Transseptal puncture, Mitral stenosis

Previously, we have reported the usefulness of transesophageal echocardiography (TEE) in the intraoperative evaluation of percutaneous transvenous mitral commissurotomy (PTMC). However, this approach has not yet to produce adequate detailed pathologic evaluation of the mitral valve. In this study, the clinical application of intracardiac echocardiography (ICE) with a 10 MHz rotating probe system (developed by us in collaboration with the Aloka Co.) in combination with TEE was investigated in cases of PTMC, and its usefulness was analyzed in comparison with TEE alone. Transseptal puncture in the right atrium was observed by TEE longitudinal images and ICE in 5 patients. In addition, the mitral valve was observed before and after the PTMC procedure using a long sheath specially designed for the ICE probe, which kept it perpendicular to the mitral valve orifice through the atrial septum. Results: 1. In ICE images, the transseptal puncture (Brockenbrough) needle is observed as a point followed by acoustic shadow, by moving the ICE probe up and down, the excursion of the needle and its approach to the septal wall can be clearly observed. If the puncture needle is forced to the atrial septum, the septal wall was clearly observed to protrude into the left atrium (tent-formation). In a tent-formation the puncture site can be determined by ICE alone, however, the puncture site can be more clearly determined when ICE and TEE are used in combination. 2. By inserting the ICE probe into the mitral valve with a long sheath through the atrial septum, frontal images of the mitral valve orifice were obtained, and the lesions of the mitral valves could be observed in detail. 3. The condition and mechanism of the commissurotomy before and after PTMC could be observed and assessed with ICE. 4. When combined with TEE, the intracardiac position of the ICE probe can be easily confirmed. In conclusion, ultrasonic diagnosis based on intracardiac echocardiography during PTMC procedures was useful for transseptal puncture and for assessing lesions of the mitral valve and the mechanism of commissurotomy. Consequently, concomitant use of intraoperative ICE and TEE may improve the safety and reliability of the procedure in PTMC.