Chen Ruo-han, Chen Ke-ping, Wang Fang-zheng, Hua Wei, Zhang Shu
Centre of Arrhythmia Diagnosis and Treatment, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China.
Chin Med J (Engl). 2006 Jun 5;119(11):925-9.
The automatic, threshold tracking, pacing algorithm developed by St. Jude Medical, verifies ventricular capture beat by beat by recognizing the evoked response following each pacemaker stimulus. This function was assumed to be not only energy saving but safe. This study estimated the extension in longevity obtained by AutoCapture (AC) compared with pacemakers programmed to manually optimized, nominal output.
Thirty-four patients who received the St. Jude Affinity series pacemaker were included in the study. The following measurements were taken: stimulation and sensing threshold, impedance of leads, evoked response and polarization signals by 3501 programmer during followup, battery current and battery impedance under different conditions. For longevity comparison, ventricular output was programmed under three different conditions: (1) AC on; (2) AC off with nominal output, and (3) AC off with pacing output set at twice the pacing threshold with a minimum of 2.0 V. Patients were divided into two groups: chronic threshold is higher or lower than 1 V. The efficacy of AC was evaluated.
Current drain in the AC on group, AC off with optimized programming or nominal output was (14.33 +/- 2.84) mA, (16.74 +/- 2.75) mA and (18.4 +/- 2.44) mA, respectively (AC on or AC off with optimized programming vs. nominal output, P < 0.01). Estimated longevity was significantly extended by AC on when compared with nominal setting [(103 +/- 27) months, (80 +/- 24) months, P < 0.01). Furthermore, compared with the optimized programming, AC extends the longevity when the pacing threshold is higher than 1 V.
AC could significantly prolong pacemaker longevity; especially in the patient with high pacing threshold.
圣犹达医疗公司研发的自动阈值跟踪起搏算法，通过识别每次起搏器刺激后的诱发反应，逐搏验证心室夺获。该功能被认为不仅节能而且安全。本研究评估了与程控为手动优化的标称输出的起搏器相比，自动夺获（AC）功能对起搏器使用寿命延长的影响。
34例接受圣犹达Affinity系列起搏器的患者纳入本研究。随访期间通过3501程控仪进行以下测量：刺激和感知阈值、导线阻抗、诱发反应和极化信号；在不同条件下测量电池电流和电池阻抗。为比较使用寿命，在三种不同条件下程控心室输出：（1）开启AC；（2）关闭AC并设置标称输出；（3）关闭AC并将起搏输出设置为起搏阈值的两倍，最低为2.0V。患者分为两组：慢性阈值高于或低于1V。评估AC的疗效。
开启AC组、关闭AC并优化程控或设置标称输出时的电流消耗分别为（14.33±2.84）mA、（16.74±2.75）mA和（18.4±2.44）mA（开启AC或关闭AC并优化程控与标称输出相比，P<0.01）。与标称设置相比，开启AC时估计的使用寿命显著延长[（103±27）个月，（80±24）个月，P<0.01]。此外，与优化程控相比，当起搏阈值高于1V时，AC可延长使用寿命。
AC可显著延长起搏器使用寿命；尤其是在起搏阈值较高的患者中。
