川田 哲嗣, 北村 惣一郎, 河内 寛治, 関 寿夫, 亀田 陽一, 長谷川 順一

Tetsuji KAWATA, Soichiro KITAMURA, Kanji KAWACHI, Toshio SEKI, Yoichi KAMEDA, Junichi HASEGAWA

奈良県立医科大学第三外科

The Third Department of Surgery, Nara Medical College

キーワード : Leaflet escape, Edwards-Duromedics bileaflet valve, Continuous wave Doppler echocardiography, Prosthetic valve dysfunction

Bileaflet prosthetic valve dysfunction due to single leaflet escape appears as a rare but fatal event. Echocardiographic reports on this event are also rare. Using 2-D and Doppler echocardiography, a case of an escaped leaflet in an Edwards-Duromedics bileaflet valve in the mitral position was diagnosed. 2-D echocardiography revealed only one moving leaflet. According to the transmitral flow velocity pattern, the pressure half-time in this case was 64 msec, and the peak velocity was 3.5 m/s. Continuous Doppler monitoring revealed a transmitral regurgitation flow pattern with a peak velocity of 5.2 m/s. There were no significant findings in the left atrium using color Doppler imaging. In 61 normally functioning Edwards-Duromedics bileaflet valves in the mitral position, the pressure half-time was below 100 msec, and the peak velocity was below 1.8 m/s. In a thrombosed valve of the same type, the pressure half-time was 119 msec, and the peak velocity was 2.6 m/s. In conclusion, we confirmed that from these differential points, this rare event can be diagnosed accurately using echocardiography.