Department of Biomedical Engineering, Istituti Clinici Scientifici Maugeri, SpA, SB, IRCCS Montescano, Montescano (PV), Italy.
Physiol Meas. 2017 Sep 26;38(10):1874-1884. doi: 10.1088/1361-6579/aa8b5a.
A novel technique to assess spontaneous baroreflex sensitivity (BRS) by bivariate phase-rectified signal averaging (PRSA-BRS) has been recently proposed and its independent prognostic power demonstrated. This method, however, has never been compared with the phenyleprine test (Phe-BRS), commonly regarded as the reference method in clinical and research applications.
In 192 heart failure (HF) and 41 post-myocardial infarction (post-MI) patients we compared PRSA-BRS with Phe-BRS, assessing both association and agreement.
Phe-BRS and PRSA-BRS were (mean ± SD) 4.8 ± 5.0 (range: -3.8,25.0) and 1.2 ± 1.5 (-2.1,6.9) ms mmHg in HF (p < 0.0001), and 5.0 ± 3.8 (-1.2,12.5) and 0.8 ± 1.7 (-2.0,6.9) ms mmHg in post-MI patients (p = 0.001). Moderate association was observed (r = 0.53, p < 0.0001 and r = 0.43, p = 0.004 in HF and post-MI, respectively). The vast majority (86% in HF and 90% in post-MI) of PRSA-BRS measurements were smaller than corresponding Phe-BRS values. The difference between PRSA-BRS and Phe-BRS was strongly dependent on the magnitude of BRS, with a trend towards more negative differences as BRS increased. Negative PRSA-BRS values were observed in 15% of HF and in 37% of post-MI patients, whereas negative Phe-BRS values were observed in 8% of HF and 5% of post-MI patients.
Although the association with Phe-BRS suggests that PRSA-BRS contains relevant information about cardiac autonomic control and reflects the strength of the baroreceptor-heart rate reflex, the marked disagreement between the two measurements indicates that PRSA-BRS measurements cannot be taken as estimates of BRS. Many factors may account for the observed lack of agreement: the different physiological conditions under which Phe-BRS and PRSA-BRS are measured, the inclusion of non-baroreflex mediated components of RR-intervals in PRSA-BRS and some computational aspects related to the normalization of PRSA-BRS values.
最近提出了一种通过双变量相位校正信号平均（PRSA-BRS）评估自发性血压反射敏感性（BRS）的新方法，并证明了其独立的预后能力。然而，该方法从未与苯肾上腺素试验（Phe-BRS）进行比较，Phe-BRS 通常被认为是临床和研究应用中的参考方法。
在 192 例心力衰竭（HF）和 41 例心肌梗死后（post-MI）患者中，我们比较了 PRSA-BRS 与 Phe-BRS，评估了两者的关联性和一致性。
HF 患者的 Phe-BRS 和 PRSA-BRS 分别为（均值±标准差）4.8±5.0（范围：-3.8，25.0）和 1.2±1.5（-2.1，6.9）ms·mmHg（p<0.0001），post-MI 患者分别为 5.0±3.8（-1.2，12.5）和 0.8±1.7（-2.0，6.9）ms·mmHg（p=0.001）。观察到中等程度的关联性（HF 和 post-MI 患者的 r 分别为 0.53，p<0.0001 和 r 为 0.43，p=0.004）。PRSA-BRS 测量值中有 86%在 HF 患者中，90%在 post-MI 患者中小于相应的 Phe-BRS 值。PRSA-BRS 与 Phe-BRS 之间的差异强烈依赖于 BRS 的幅度，随着 BRS 的增加，差异呈负向趋势。HF 患者中有 15%出现负性 PRSA-BRS 值，post-MI 患者中有 37%出现负性 PRSA-BRS 值，而 HF 患者中有 8%出现负性 Phe-BRS 值，post-MI 患者中有 5%出现负性 Phe-BRS 值。
尽管与 Phe-BRS 的关联表明 PRSA-BRS 包含了关于心脏自主控制的相关信息，并反映了压力感受器-心率反射的强度，但两种测量方法之间的显著差异表明，PRSA-BRS 测量值不能作为 BRS 的估计值。许多因素可能导致观察到的缺乏一致性：在测量 Phe-BRS 和 PRSA-BRS 时，不同的生理条件、PRSA-BRS 中 RR 间期的非压力反射介导成分以及与 PRSA-BRS 值归一化相关的一些计算方面。
