Machejek Jakub, Machejek Joanna, Lelakowska-Pieła Maria, Engel Anna, Domaracki Donat, Lelakowski Jacek
Department of Electrocardiology, The John Paul II Hospital in Kraków.
Jagiellonian University.
Pol Merkur Lekarski. 2015 Aug;39(230):81-5.
Pacemaker working time, which was in the beginning not more than one year, reached the maximum in the first half of the 70s, then shortened to between a few to several years. Aim of the study was investigated the electrical properties of the endocavitary pacemaker leads, considered the possibility of manufacturing a longlasting pacemaker ("lifetime pacemaker") and examined the preference of patients in relation to dimensions of the implanted device.
The investigation included 190 electrodes with cathodes coated with titanium nitride (TIJ and TIR), 244--coated with iridium (SXA and SXV) and 90--coated with black platinum (DXA and DXV). A formula was developed to calculate the estimated pacemaker longevity: Longevity (years)=Qog (Ah)x10(6)/8760x[Isp (μA)+Ist (μA)], where Qog is the capacity of the electric cell, Ist--current stimulation, Isp--quiescent current of the generator. The survey was performed in a group of 145 patients with pacemakers, using an original questionnaire.
All the tested electrodes manifested a good acute and distant pacing threshold and the small intra-electrode differences were not clinically significant. In distant measurement, the average rheobasis of the steroid platinum electrode was 0.59 V and the chronaxie was 0.23 ms. These parameters have direct impact on modern pacemaker programming methods. It was proven that increasing the electric cell capacity in the DDD pacemaker by every one-tenth of ampere-hours caused a significant increase in the working time (p=0.000). Thus, the increase of the electric cell capacity allows for returning to the concept of a "lifetime pacemaker". The results of the survey showed that patients were willing to accept larger, but longlasting pacemakers (p=0.000).
The tested passive and active electrode with a fractalcoated cathode ensured good electrical parameters within several months of observation. The electrode equipped with dexamethasone deposit showed no advantage in terms of the stimulation threshold when compared to the passive electrode coated with titanium nitride. Significant differences in the pacing threshold, which were detected between the leads with different cathode coatings, had little effect on pacemaker longevity. The most extensive impact on the generator longevity was exerted by the capacity of the electrical cell and pacemaker quiescent current. Patients were able to accept a much larger device than currently produced providing a long working time was ensured.
起搏器工作时间最初不超过一年，在70年代上半叶达到最长，随后缩短至几年到数年不等。本研究的目的是研究心腔内起搏器导线的电性能，考虑制造持久起搏器（“终身起搏器”）的可能性，并研究患者对植入装置尺寸的偏好。
研究包括190根阴极涂有氮化钛（TIJ和TIR）的电极、244根涂有铱（SXA和SXV）的电极以及90根涂有黑铂（DXA和DXV）的电极。开发了一个公式来计算估计的起搏器寿命：寿命（年）=Qog（Ah）×10⁶/8760×[Isp（μA）+Ist（μA）]，其中Qog是电池容量，Ist是电流刺激，Isp是发生器的静态电流。使用一份原始问卷对145名植入起搏器的患者进行了调查。
所有测试电极均表现出良好的急性和远期起搏阈值，电极内差异较小，在临床上无显著意义。在远期测量中，类固醇铂电极的平均基强度为0.59 V，时值为0.23 ms。这些参数对现代起搏器编程方法有直接影响。事实证明，在DDD起搏器中，将电池容量每增加十分之一安时，工作时间就会显著增加（p = 0.000）。因此，电池容量的增加使得可以回归到“终身起搏器”的概念。调查结果表明，患者愿意接受更大但持久的起搏器（p = 0.000）。
经测试的带有分形涂层阴极的被动和主动电极在几个月的观察期内确保了良好的电参数。与涂有氮化钛的被动电极相比，配备地塞米松沉积物的电极在刺激阈值方面没有优势。不同阴极涂层的导线之间检测到的起搏阈值的显著差异对起搏器寿命影响不大。对发生器寿命影响最大的是电池容量和起搏器静态电流。如果能确保较长的工作时间，患者能够接受比目前生产的设备大得多的装置。
