Pulsewatch: Smartwatch Monitoring for Atrial Fibrillation After Stroke

System usability scale, self-reported, of likes, dislikes, and problems encountered with the smartphone application and smartwatch. Each item regarding likes and dislikes will be scored 1-5 (1= strongly disagree; 5= strongly agree or Didn't use). Problem encountered will be scored with yes or no options with space provided for explanations. Also, using Mobile Application Rating Scale (MARS) App Classification questions will capture the participants' experience with the application. Each MARS item uses a 5-point scale (1=inadequate, 2=poor, 3=acceptable, 4=Good, 5=Excellent) and sub-scales will have an average mean to indicate the overall rating of the application.

Number of participants with SUS > 68 was reported in the Outcome Measure Data Table

This outcome was measured by the number of atrial fibrillation episodes identified by the smartwatch biosensors. This was conducted using two approaches. Firstly, the Pulsewatch app sent a message to participants to remain still and perform a 30-sec ECG self-check (wrist electrode, high accuracy) should they have an AF episode detected. The second approach involved the cancellation of cyclical frequencies, seen in accelerometer data, from the photoplethysmogram (PPG) signal. Thus, these two approaches were effectively used to recover some data segments contaminated by MNA or by poor signal quality and correctly identified the presence or absence of AF. Once MN artifacts were corrected, we looked at patterns to analyze pulse waveforms for AF detection, including discrimination of PVCs and PACs

Episodes of atrial fibrillation was identified by the gold-standard monitor (Cardea Solo by Cardiac Insight). The Cardiac Insight patches have a module chip inside the sensor that stores the data being collected over the 14-days. After the participants returned the patches at the end of the 14-day monitoring period, a trained study staff removed the modules and placed them into the Cardiac insight smart cable to be uploaded to a UMass Medical School server. The ECG readings are then read by a board-certified cardiologist to confirm true atrial fibrillation detection.

Anxiety will be assessed using the Generalized Anxiety Disorder-7 scale (GAD-7), a revised version of the anxiety module from the Patient Health Questionnaire, which consists of Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria for generalized anxiety disorder over the past 2 weeks. The GAD-7 score ranges from 0-27 with scores of 5, 10 and 15 representing validated cut-points for mild, moderate and severe levels of anxiety symptoms, with a score ≥10 having high sensitivity (0.89) and specificity (0.82) for psychiatrist diagnosed anxiety disorder and correlates significantly with health-related QoL. This change in outcome was between baseline and the last study visit 30 days post the second randomization.

The Short Form (SF-12) health survey to assess health related quality of life, this validated instrument domains include general health questions and mental health related questions. Scores range from 0 to 100, where higher scores indicate higher level of health. This change in outcome was between baseline and the last study visit 30 days post the second randomization (44 days).

The Short Form (SF-12) health survey to assess health related quality of life, this validated instrument domains include general health questions and physical health-related questions. Scores range from 0 to 100, where higher scores indicate a higher level of health. This outcome was assessed at baseline and at the last study visit 30 days post the second randomization (44 days).

Self-efficacy for disease management is associated with engagement in health behaviors and with improved medication adherence. The General Disease Management scale is a 5-item scale assessing confidence in disease self-management (scores 0-50, higher scores = greater confidence, lower scores = lower confidence). This change in outcome was between baseline and 14 days post the first randomization.

Self-efficacy for disease management is associated with engagement in health behaviors and with improved medication adherence. The Symptom Management scale is a 5-item scale assessing confidence in managing chronic disease symptoms (items tailored to the sample), with scores ranging from 0 to 100. A higher symptom management score indicates a higher confidence in managing symptoms. Conversely, a lower score indicates a lower confidence in managing symptoms. This change in outcome was between baseline and 14 days post randomization.

Patient activation refers to a patient's ability and willingness to manage their health. Activation will be measured using the 10-item Consumer Health Activation Index (CHAI). Scores range from 10 to 60. A higher score indicates that the patient has higher activation for self-management of their condition. Conversely, a lower score indicates lower activation for self-management of their condition. This change in outcome was between the baseline and the last study visit 30 days post the second randomization (44 days)

Medication adherence will be measured using the 12-item Adherence to Refills and Medications Scale (ARMS), a well-validated measure of patient-reported adherence. The minimum to maximum ARMS score ranges from 1 to 4. Higher scores indicate poorer adherence, and lower scores indicate better medication adherence. This change in outcome was between baseline and 14 days post the first randomization.