Celiker A, Alehan D, Tokel N K, Lenk M K, Ozme S
Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey.
Eur Heart J. 1996 Aug;17(8):1251-5. doi: 10.1093/oxfordjournals.eurheartj.a015043.
The efficacy of a new single-chamber, rate-responsive pacemaker that utilizes information from two sensors, activity and stimulus to T wave, was evaluated in 15 children during a mean follow-up period of 10.3 +/- 3.3 months (range 5-16 months). There were 10 males and five females, with a mean age of 5.9 +/- 3.8 years (range 9 months-16 years). The indication for pacing was high grade atrioventricular block in 10 (eight postoperative, two congenital), and sinus node dysfunction in five patients. In endocardial implants the mean T wave amplitude was 2.48 +/- 0.7 mV, and mean T wave sensing 91 +/- 6.3%, whereas in epicardial implants T wave amplitude and sensing were inadequate. Each patient underwent 24-h Holter monitoring and 10 performed a graded treadmill test in three sensor-blending modes (Stimulus-T = Activity, Stimulus-T > Activity, Stimulus-T < Activity), using the chronotropic assessment exercise protocol. Sensor cross-checking was analysed by continuous tapping over the pacemaker. Holter monitoring demonstrated that pacing rate variations were closely related to daily activity. At the initial phases of exercise testing, the mean percentage of increase in pacing rate was significantly lower in Stimulus-T > Activity mode, when compared to Stimulus-T = Activity (P < 0.01); however, the initial disparity among the three modes disappeared halfway through the exercise and similar heart rate changes were observed thereafter. Continuous tapping over the pacemaker in Stimulus-T = Activity mode caused an initial increase in pacing rate, and inappropriate responses were quickly corrected by sensor cross-checking. Rate modulation with a single-chamber, dual-sensor pacemaker is adequate and safe in children, and may offer significant advantages over single-sensor devices in endocardial implants.
一款新型单腔、频率应答式起搏器利用活动和刺激到T波这两个传感器的信息，在15名儿童中进行了评估，平均随访期为10.3±3.3个月（范围5 - 16个月）。其中男性10名，女性5名，平均年龄5.9±3.8岁（范围9个月至16岁）。起搏指征为10例高度房室传导阻滞（8例术后，2例先天性），5例窦房结功能障碍。心内膜植入时平均T波振幅为2.48±0.7 mV，平均T波感知率为91±6.3%，而心外膜植入时T波振幅和感知率不足。每位患者均接受了24小时动态心电图监测，10名患者按照变时性评估运动方案，在三种传感器融合模式（刺激 - T = 活动、刺激 - T > 活动、刺激 - T < 活动）下进行了分级平板运动试验。通过持续轻敲起搏器对传感器交叉检查进行分析。动态心电图监测显示起搏频率变化与日常活动密切相关。在运动测试初始阶段，与刺激 - T = 活动模式相比，刺激 - T > 活动模式下起搏频率增加的平均百分比显著更低（P < 0.01）；然而，三种模式之间的初始差异在运动进行到一半时消失，此后观察到类似的心率变化。在刺激 - T = 活动模式下持续轻敲起搏器会导致起搏频率初始增加，且不适当的反应会通过传感器交叉检查迅速纠正。单腔、双传感器起搏器在儿童中进行频率调制是充分且安全的，在心内膜植入方面可能比单传感器设备具有显著优势。
