Chambers J, McLoughlin N, Rapson A, Jackson G
Cardiac Unit, King's College Hospital, London.
Br Heart J. 1988 Dec;60(6):502-6. doi: 10.1136/hrt.60.6.502.
To test the validity of a relation between the pressure half time and the diastolic time interval, previously shown in a pulse duplication system, eight patients with prosthetic mitral valves and permanent pacemaker systems were studied. Recordings were made from the apex by continuous wave or pulsed Doppler echocardiography at heart rates between 75 and 150 beats/min. The pressure half time was found to be closely correlated with the diastolic time interval although there was individual variation and in three prostheses the pressure half time attained a plateau when the diastolic time interval was more than 300 ms. It is likely that the orifice area is the main controller of pressure half time where there is stenosis of the prosthesis, but that other factors such as ventricular or atrial compliance and the diastolic time interval may modify or obscure the effect of orifice area in normally functioning prosthetic valves.
为了验证先前在脉冲复制系统中显示的压力半衰期与舒张时间间隔之间关系的有效性，对8例人工二尖瓣和永久性起搏器系统患者进行了研究。在心率为75至150次/分钟之间时，通过连续波或脉冲多普勒超声心动图从心尖进行记录。尽管存在个体差异，且在三个假体中，当舒张时间间隔超过300毫秒时压力半衰期达到平台期，但发现压力半衰期与舒张时间间隔密切相关。在假体存在狭窄的情况下，孔口面积可能是压力半衰期的主要控制因素，但其他因素，如心室或心房顺应性以及舒张时间间隔，可能会改变或掩盖正常功能人工瓣膜中孔口面积的影响。
