Beau Scott, Greer Stephen, Ellis Christopher R, Keeney Jeffrey, Asopa Shubha, Arnold Edith, Fischer Avi
Arkansas Heart Hospital, Little Rock, AR, USA.
Baptist Health Medical Center, Little Rock, AR, USA.
J Interv Card Electrophysiol. 2016 Mar;45(2):225-32. doi: 10.1007/s10840-015-0081-6. Epub 2016 Jan 6.
Implantable cardioverter-defibrillators (ICD) provide treatment for life-threatening ventricular tachyarrhythmias. Failure of the pace/sense conductor of an ICD lead can cause noise on the sensing electrogram (EGM) that may be misinterpreted as ventricular activity, triggering inappropriate therapy. An algorithm based upon the confirmation of ventricular activity from a far-field EGM has been developed to reduce inappropriate therapies resulting from this type of lead failure, while ensuring that appropriate therapy is delivered. The objectives of this study were to evaluate the algorithm's ability to discriminate lead noise from ventricular tachycardia/ventricular fibrillation (VT/VF) and to determine whether it inhibits inappropriate shocks without delaying appropriate shocks.
The algorithm was prospectively tested using near- and far-field EGM recordings from patients in three conditions: normal sinus rhythm with sustained and non-sustained lead noise via manipulation of the ICD pocket or lead system, and VT/VF induced during defibrillation threshold testing. The recordings were played through a bench-top device running the algorithm with the diagnosis, time to diagnosis, and inhibition of therapy documented.
The algorithm detected noise and withheld inappropriate therapy in 231 of 238 recordings of sustained lead noise that would otherwise have been diagnosed as VT/VF (97.1%). Non-sustained lead noise was correctly diagnosed in 47 of the 52 recordings (90.4%). The device appropriately identified all 853 recordings of VT/VF (100%), without an increase in the time to detection (0.01 ± 0.14 s).
The SecureSense(TM) algorithm correctly diagnosed sustained and non-sustained lead noise recordings without compromising detection of VT/VF. Use of the algorithm may reduce inappropriate shocks and alert clinicians to lead noise indicative of lead failure.
植入式心脏复律除颤器（ICD）可治疗危及生命的室性快速心律失常。ICD导线的起搏/感知导体故障可导致感知电图（EGM）出现噪声，这可能被误判为心室活动，从而引发不适当的治疗。已开发出一种基于远场EGM确认心室活动的算法，以减少因这类导线故障导致的不适当治疗，同时确保能提供适当的治疗。本研究的目的是评估该算法区分导线噪声与室性心动过速/心室颤动（VT/VF）的能力，并确定其是否能在不延迟适当电击的情况下抑制不适当电击。
该算法通过对处于三种状态的患者进行近场和远场EGM记录进行前瞻性测试：正常窦性心律，通过操作ICD囊袋或导线系统产生持续性和非持续性导线噪声，以及在除颤阈值测试期间诱发VT/VF。记录通过运行该算法的台式设备播放，并记录诊断结果、诊断时间和治疗抑制情况。
在238次持续性导线噪声记录中，有231次（97.1%）算法检测到噪声并抑制了不适当治疗，否则这些记录会被诊断为VT/VF。52次非持续性导线噪声记录中有47次（90.4%）被正确诊断。该设备正确识别了所有853次VT/VF记录（100%），检测时间没有增加（0.01±0.14秒）。
SecureSense™算法能正确诊断持续性和非持续性导线噪声记录，且不影响对VT/VF的检测。使用该算法可能会减少不适当电击，并提醒临床医生注意导线故障的导线噪声。
