Center for Cardiac Arrhythmias of Genetic Origin, IRCCS Istituto Auxologico Italiano, Milan, Italy.
Department of Geriatrics and Cardiovascular Medicine, IRCCS Istituto Auxologico Italiano, Milan, Italy.
Int J Cardiol. 2018 Sep 1;266:89-94. doi: 10.1016/j.ijcard.2018.03.097.
A correct measurement of the QT interval in the out-of-hospital setting is important whenever the long QT syndrome (LQTS) is suspected or a therapy might lead to drug-induced LQTS (diLQTS) because QT interval monitoring in the initial days of therapy could alert to dangerous QT prolongation. We explored whether automated QTc measurements (BGM) by BodyGuardian™ (BG), a wearable remote monitoring system, are sufficiently reliable compared to our own manual measurements (MM) performed on the same beats during 12‑lead Holter recordings in LQTS patients (pts) and in healthy controls.
We performed 351 measurements in 20 LQTS pts and 16 controls. MM and BGM were compared by a Bland-Altman plot (BAp). High values of BAp indicate large differences between measurements.
In all 36 subjects QTc was 446 ± 41 and 445 ± 47 ms in MM and BGM, respectively. The mean ± SE BAp was -1.4 ± 1.8 ms for QTc in all subjects, 8.3 ± 2.3 and -7.2 ± 2.5 ms respectively in controls and LQTS. The disagreement between BGM and MM <15 ms in all, in controls, and in LQTS was respectively 57%, 63% and 54%. Among controls, there were only 3/132 false positive measurements (BGM QTc >470 ms when MM QTc <440 ms) in 3 different subjects. Among LQTS, there were 10/219 false negative measurements (BGM QTc <440 ms when MM QTc >470 ms) in 6 pts, but only two had multiple false negative values.
This wearable monitoring system reliably identifies a prolonged QT interval and probably also subjects at risk for diLQTS.
在怀疑长 QT 综合征（LQTS）或治疗可能导致药物诱导的长 QT 综合征（diLQTS）的情况下，在院外环境中正确测量 QT 间期非常重要，因为在治疗的最初几天进行 QT 间期监测可以提醒注意危险的 QT 延长。我们探讨了 BodyGuardian™（BG），一种可穿戴远程监测系统的自动 QTc 测量（BGM）是否与我们在 LQTS 患者和健康对照者 12 导联 Holter 记录期间同一搏动上进行的手动测量（MM）相比足够可靠。
我们对 20 名 LQTS 患者和 16 名对照者进行了 351 次测量。通过 Bland-Altman 图（BAp）比较 MM 和 BGM。BAp 高值表示测量之间存在较大差异。
在所有 36 名受试者中，MM 和 BGM 中的 QTc 分别为 446±41 和 445±47 ms。所有受试者的平均±SE BAp 为 -1.4±1.8 ms，对照组和 LQTS 患者分别为 8.3±2.3 和 -7.2±2.5 ms。在所有受试者中，BGM 和 MM 之间的差异<15 ms，在对照组和 LQTS 患者中分别为 57%、63%和 54%。在对照组中，在 3 名不同受试者中，只有 3/132 次（BGM QTc>470 ms 时 MM QTc<440 ms）出现假阳性测量。在 LQTS 患者中，有 10/219 次（BGM QTc<440 ms 时 MM QTc>470 ms）出现假阴性测量在 6 名患者中，但只有 2 名患者有多个假阴性值。
这种可穿戴监测系统可靠地识别延长的 QT 间期，并且可能还识别出 diLQTS 的风险患者。
