Binkley Philip F, Porterfield James G, Porterfield Linda M, Beau Scott L, Corbisiero Raffaele, Greer G Stephen, Love Charles J, Turkel Melanie, Bjorling Anders, Qu Fujian, Farazi Taraneh G
Division of Cardiovascular Medicine, College of Medicine, College of Public Health, The Ohio State University, Columbus, OH, USA.
J Interv Card Electrophysiol. 2012 Nov;35(2):197-206. doi: 10.1007/s10840-012-9693-2. Epub 2012 Jun 12.
Pulmonary edema (PE) is associated with fluid accumulation in the lungs. Device-based impedance measurements have been used to detect fluid overload prior to hospitalization. However, studies have reported a high false positive rate (FPR). The objective of this study was to develop and test a new multivector impedance-based algorithm that reliably tracks PE clinical events.
We enrolled patients with implanted CRT-Ds in 23 US centers within 2 weeks of device implant. Six-vector impedance data was collected automatically by the CRT-Ds every 30 min during emergency department visits/hospitalizations and every 2 h at all other times. Detection algorithms for cardiac resynchronization therapy defibrillator (CRT-D) and implantable cardiac defibrillator (ICD) devices were developed using those impedance vectors that would be available in corresponding devices and retrospectively evaluated.
There were 75 patients (69 % male), mean age 66 ± 12 years, with a LVEF of 23 ± 6 % and QRS of 149 ± 25 ms. Twenty-one major clinical events occurred over 8.2 ± 2.6 months of follow-up time. CRT-D vector combinations resulted in a sensitivity of 71.4 % (95 % confidence interval 47.8-88.7) and a FPR of 0.56 (0.30-0.94) false positives per patient-year (FPs/pt-yr); ICD vector combinations resulted in a sensitivity of 61.9 % (38.4-81.9) and a FPR of 0.63 (0.36-0.90) FPs/pt-yr. In comparison, the single-vector RVCoil-Can implementation of this algorithm resulted in a sensitivity of 57.1 % (34.0-78.2) and a FPR of 0.74 (0.44-1.12) FPs/pt-yr.
This multivector impedance algorithm was effective in tracking PE clinical events in this patient population. Additional studies are needed to prospectively evaluate the performance of this algorithm in a larger population.
肺水肿（PE）与肺内液体蓄积有关。基于设备的阻抗测量已被用于在住院前检测液体过载。然而，研究报告称假阳性率（FPR）很高。本研究的目的是开发并测试一种新的基于多向量阻抗的算法，该算法能可靠地跟踪PE临床事件。
我们在美国23个中心招募了在设备植入后2周内植入CRT-D的患者。在急诊科就诊/住院期间，CRT-D每30分钟自动收集一次六向量阻抗数据，在其他所有时间每2小时收集一次。使用相应设备中可用的那些阻抗向量开发了心脏再同步治疗除颤器（CRT-D）和植入式心脏除颤器（ICD）设备的检测算法，并进行回顾性评估。
共有75例患者（69%为男性），平均年龄66±12岁，左心室射血分数（LVEF）为23±6%，QRS波时限为149±25毫秒。在8.2±2.6个月的随访期内发生了21次主要临床事件。CRT-D向量组合的灵敏度为71.4%（95%置信区间47.8 - 88.7），每名患者每年的假阳性率（FPs/pt-yr）为0.56（0.30 - 0.94）；ICD向量组合的灵敏度为61.9%（38.4 - 81.9），FPR为0.63（0.36 - 0.90）FPs/pt-yr。相比之下，该算法的单向量右心室线圈-外壳实现方式的灵敏度为57.1%（34.0 - 78.2），FPR为0.74（0.44 - 1.
