Objective: We developed a wearable watch-based device to provide noninvasive, cuff-less blood pressure (BP) estimation in an at-home setting. Methods: The watch measures single-lead electrocardiogram (ECG), tri-axial seismocardiogram (SCG), and multi-wavelength photoplethysmogram (PPG) signals to compute the pulse transit time (PTT), allowing for BP estimation. We sent our custom watch device and an oscillometric BP cuff home with 21 healthy subjects, and captured the natural variability in BP over the course of a 24-hour period. Results: After calibration, our Pearson correlation coefficient (PCC) of 0.69 and root-mean-square-error (RMSE) of 2.72 mmHg suggest that noninvasive PTT measurements correlate with around-the-clock BP. Using a novel two-point calibration method, we achieved a RMSE of 3.86 mmHg. We further demonstrated the potential of a semi-globalized adaptive model to reduce calibration requirements. Conclusion: This is, to the best of our knowledge, the first time that BP has been comprehensively estimated noninvasively using PTT in an at-home setting. We showed a more convenient method for obtaining ambulatory BP than through the use of the standard oscillometric cuff. We presented new calibration methods for BP estimation using fewer calibration points that are more practical for a real-world scenario. Significance: A custom watch (SeismoWatch) capable of taking multiple BP measurements enables reliable remote monitoring of daily BP and paves the way towards convenient hypertension screening and management, which can potentially reduce hospitalizations and improve quality of life.

中文翻译：

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通过脉冲传输时间在家中估计可穿戴式无袖带血压

客观的：我们开发了一种基于手表的可穿戴设备，可在家庭环境中提供无创、无袖带血压 (BP) 估计。方法：该手表测量单导联心电图 (ECG)、三轴地震心电图 (SCG) 和多波长光电体积描记图 (PPG) 信号以计算脉搏传输时间 (PTT)，从而进行 BP 估计。我们将我们的定制手表设备和示波血压袖带带回家，带 21 名健康受试者，并在 24 小时内捕捉到血压的自然变化。结果：校准后，我们​​的 Pearson 相关系数 (PCC) 为 0.69，均方根误差 (RMSE) 为 2.72 mmHg，表明无创 PTT 测量与全天候 BP 相关。使用一种新颖的两点校准方法，我们实现了 3.86 mmHg 的 RMSE。我们进一步证明了半全球化自适应模型在减少校准要求方面的潜力。结论：据我们所知，这是首次在家庭环境中使用 PTT 无创全面地估计 BP。我们展示了一种比使用标准示波袖带更方便的获取动态血压的方法。我们提出了新的 BP 估计校准方法，使用更少的校准点，这对于现实世界的场景更实用。意义：能够进行多次血压测量的定制手表 (SeismoWatch) 能够可靠地远程监测每日血压，并为方便的高血压筛查和管理铺平道路，这可能会减少住院治疗并提高生活质量。