心室空白期的测定及其临床意义

Determining and Clinical Significance of Ventricular Blanking Interval

观察了12例值入 DDD 起搏器患者的心室空白期(VBI),旨在介绍测定 VBI 的一种方法,并对有关问题作一初步评价。12例患者中植入 CPI 公司937型 DDD 起搏器9例、941型1例,Biotronik 公司 Gemnos 型2例。平均植入时间21.5±12.5(1～43)月,均在寿命期内,且工作正常。使用程序胸壁刺激试验(PCWS),对上述起搏器的 VBI 进行检测。结果显示,实测的 VBI 在 CPI 及 Biotronik 起搏器中分别为58±12.5和45±5.0 ms,前者较出厂额定值(32ms)明显延长(P<0.05),后者未说明出厂额定值。临床观察证实,在某些情况下较长的 VBI 会产生竞争心律及可能导致恶性心律失常。PCWS 用于临床测定 DDD 起搏器的 VBI,是简单、安全并且可靠的方法。VBI 的设置不宜过长,其数据应以实测值为准。

The method of determining ventricular blanking interval(VBI) was introduced and VBI clinical signifi- cance was ewaluated in this paper.In 12 patients with DDD-mode cardiac pacemakers which consisted of nine Model 937 and one Model 941 of CPI and two Model Gemnos of Biotronik,the VBIs of these implanted pacemakers were determined with programmed chest wall stimulation test (PCWS).These determined pacemakers had a mean im- planted period of 21.5±12.5(1-43) months and were all in life cycle with normal operation.As a result,VBI showed obvious higher determined value (58±12.5 ms) than the standard value (32 ms) of manufacture (P<0. 01) in the units of CPI and 45±5 ms of determined value without the standard value in the units of Biotronik.The clinical studies suggests that a wider VBI of DDD-mode cardiac pacemaker is unappropriate and may result in com- petitive rhythm and malign arrhythmia.The present studies show that PCWS is a simple,safe and effective method in determining VBI of DDD pacemaker,a determined value of VBI is more significant than the standard value of manufacture.