Department of Cardiology II - Electrophysiology, University Hospital Münster, Münster, Germany.
J Cardiovasc Electrophysiol. 2018 Sep;29(9):1241-1247. doi: 10.1111/jce.13647. Epub 2018 Jun 19.
The subcutaneous implantable cardioverter defibrillator (S-ICD) has been established as a valuable alternative to transvenous ICD for prevention of sudden cardiac death. The system automatically chooses the optimal sensing vector. However, during follow-up and especially after device replacement we observed a change of the suggested sensing vector in automatic setup. Therefore, we analyzed frequency and reasons of vector change and its impact on inappropriate shocks (IAS).
Between June 2010 and December 2017, a total of 216 patients with S-ICD were included in this analysis. In all patients sensing vectors at the time of implantation, during follow-up, and after device replacement were investigated. Median follow-up time was 27.3 ± 25.3 months.
A change of the initial vector was seen in 77 patients (35.7%). The most frequent reason for vector change was the postoperative setup in supine and erect position in 54 patients (70.1%). In 12 patients (15.5%), the vector was manually changed due to inappropriate sensing and/or therapies. Routine setup during follow-up led to automatic vector change in 10 cases (13.0%). In only 1 patient the vector was manually changed due to oversensing in an exercise treadmill test. In 27 patients, the device was replaced due to battery depletion and in 6 of these patients the sensing vector was changed by the automatic setup. Vector change did not have an impact for inappropriate therapies in the follow-up; only 1 patient received an IAS due to an inadvertent vector change after device replacement.
In the present study, a significant number of S-ICD patients had a manual or automatic vector change during follow-up and after device replacement. The study underlines the importance of a thoroughly performed screening and at least two valuable sensing vectors preimplant. Further studies are needed to evaluate the necessity of a routine automatic setup during follow-up.
皮下植入式心律转复除颤器（S-ICD）已被确立为预防心源性猝死的经静脉植入式心律转复除颤器的一种有价值的替代方法。该系统自动选择最佳的感知向量。然而，在随访过程中，特别是在设备更换后，我们观察到自动设置中建议的感知向量发生了变化。因此，我们分析了向量变化的频率、原因及其对不适当电击（IAS）的影响。
在 2010 年 6 月至 2017 年 12 月期间，共有 216 例 S-ICD 患者纳入本分析。所有患者均对植入时、随访时和设备更换后的感知向量进行了研究。中位随访时间为 27.3±25.3 个月。
77 例患者（35.7%）初始向量发生变化。向量变化最常见的原因是 54 例患者（70.1%）术后仰卧位和直立位的自动设置。12 例患者（15.5%）因感知不良和/或治疗而手动更改向量。随访期间的常规设置导致 10 例（13.0%）自动更改向量。只有 1 例患者因运动平板试验中的过感知而手动更改向量。27 例患者因电池耗尽更换设备，其中 6 例患者因自动设置而更改感知向量。在随访期间，向量变化对不适当治疗没有影响；仅 1 例患者因设备更换后无意的向量变化而发生 IAS。
在本研究中，相当数量的 S-ICD 患者在随访期间和设备更换后进行了手动或自动向量更改。该研究强调了彻底进行筛选和植入前至少获得两个有价值的感知向量的重要性。需要进一步研究来评估在随访期间进行常规自动设置的必要性。
