Institute of Cardiology, University of Bologna, Azienda Ospedaliera S.Orsola-Malpighi, Bologna, Italy.
Int J Cardiol. 2012 Jan 26;154(2):134-40. doi: 10.1016/j.ijcard.2010.09.005. Epub 2010 Oct 14.
Many ICD carriers experience inappropriate shocks, but the relative merits of dual- /single-chamber devices for arrhythmia discrimination still remain unclear. We explored possible advantages of the atrial data provided by dual-chamber implantable defibrillators (ICD) for discrimination of real-life supraventricular/ventricular tachyarrhythmias (SVT/VT).
100 dual-chamber traces from 24 ICD were blindly reviewed in dual-chamber and simulated single-chamber (with/without discriminator data) reading modes by five electrophysiologists who determined chamber of origin and provided Likert-scale "confidence" ratings. We assessed 1) intra/interobserver concordance; 2) diagnostic accuracy, using expert diagnoses as a reference standard; 3) ROC curves of sensitivity/specificity of "likelihood perception" scores, generated by combining chamber-of-origin diagnostic judgments with Likert-scale "confidence" ratings. We also assessed diagnostic accuracy of automated discrimination by all possible dual-/single-chamber algorithm configurations.
Interobserver concordance was "substantial" (modified Cohen kappa-test values for dual-/single-chamber, 0.79/0.68); intraobserver concordance "almost complete" (kappa ≥ 0.89). Dual-chamber mode provided best diagnostic sensitivity/specificity (99%/92%) and highest reader confidence (p<0.001). Area under ROC curves of sensitivity/specificity values for the "likelihood perception" score (representing electrophysiologists' perceptions of the likelihood that an episode was of ventricular origin) was highest in dual-chamber mode (0.98 vs. 0.93 for both single-chamber modes; p<0.001). Regarding automated discrimination, all four dual-chamber configurations conferred 100% sensitivity (specificity values ranged 39%-88%), whereas single-chamber configurations appeared inferior (best sensitivity/specificity combination, 89%/64%).
Availability of the atrial channel helps in reducing inappropriate ICD therapies by providing relevant advantages in terms of both appropriate cardiologist's post-hoc discrimination of SVT/VT (improving program tailoring) and automated arrhythmia discrimination.
许多 ICD 携带者经历了不适当的电击，但双腔/单腔设备在心律失常鉴别方面的相对优势仍不清楚。我们探讨了双腔植入式除颤器（ICD）提供的心房数据在鉴别真实的室上性/室性心动过速（SVT/VT）方面的可能优势。
24 例 ICD 中的 100 例双腔轨迹由 5 名电生理学家进行盲法双腔和模拟单腔（带/不带鉴别器数据）阅读模式的回顾，他们确定起源腔室，并提供 Likert 量表“信心”评分。我们评估了 1）观察者内/间的一致性；2）使用专家诊断作为参考标准的诊断准确性；3）由起源腔室诊断判断与 Likert 量表“信心”评分相结合生成的“可能性感知”评分的敏感性/特异性的 ROC 曲线。我们还评估了所有可能的双/单腔算法配置的自动鉴别诊断的准确性。
观察者间一致性为“中等”（双腔/单腔的改良 Cohen kappa 检验值，0.79/0.68）；观察者内一致性“几乎完全”（kappa≥0.89）。双腔模式提供了最佳的诊断敏感性/特异性（99%/92%）和最高的读者信心（p<0.001）。“可能性感知”评分的敏感性/特异性 ROC 曲线下面积在双腔模式下最高（0.98 比两种单腔模式均为 0.93；p<0.001）。关于自动鉴别，所有四种双腔配置的敏感性均为 100%（特异性值范围为 39%-88%），而单腔配置则表现较差（最佳敏感性/特异性组合为 89%/64%）。
心房通道的可用性通过提供适当的心脏病专家对 SVT/VT 进行事后鉴别（改善程控调整）和自动心律失常鉴别方面的相关优势，有助于减少 ICD 不适当的治疗。
