Validation of blood pressure measurement using a smartwatch in patients with acute ischemic stroke

We aimed to validate the accuracy of blood pressure (BP) measurement using a smartwatch in patients with acute ischemic stroke. We compared 140 pairs of BP (n = 35) measurements acquired by a smartwatch (ASUS VivoWatch SP) with those measured by a sphygmomanometer (reference device). Differences between the smartwatch BP and reference BP measurements were compared. The validation procedure and criterion followed the consensus of the American National Standards Institute, Inc/Association for the Advancement of Medical Instrumentation/International Organization for Standardization (ANSI/AAMI/ISO) 81060-2:2018 and extended the standard to the specificities of cuffless devices in acute ischemic stroke population. The mean and standard deviation of the differences measured by a smartwatch and reference device were 1.8 ± 5.7 mm Hg in systolic BP and 0.7 ± 3.6 mm Hg in diastolic BP according to criterion 1. The mean and standard deviation of the differences measured by a smartwatch and reference device were 1.8 ± 5.6 mm Hg in systolic BP and 0.7 ± 3.6 mm Hg in diastolic BP according to criterion 2. The results both met the standards of the 2 criterion. The validation result did not differ between the paralytic and non-paralytic arms. The smartwatch with photoplethysmography sensors can provide accurate and reliable measurement of BP in acute ischemic stroke patients.