* Evaluate for accuracy and reproducibility of data collected via the participant-operated Walk.Talk.Track. (WTT) app combined with Apple Watch during in-clinic, technician proctored 6MWT's. * Determine whether the WTT app on the Apple Watch can accurately collect information on distance traveled and heart rate (HR) during in-clinic 6MWT run by American Thoracic Society (ATS) guidelines * Determine whether participants can operate the WTT app and Apple Watch effectively to gather accurate data in a monitored and home-based setting * Prospectively monitor for changes in WTT app recorded 6MWT results following initiation of therapy in a treatment naïve cohort of PAH participants * Evaluate whether changes from baseline in 6 minute walk distance (6MWD) and heart rate recovery at one minute (HRR1) as well as other variables that have been associated with disease severity in PAH and left-sided heart disease (resting HR, heart rate variability \[HRV\], chronotropic index \[CI\]) can be identified before the 12-week follow up when comparing the treatment arm and the control arm * Evaluate whether changes from baseline in the HRR1, resting HR, HRV and/or CI are more evident in treatment responders when compared to treatment non-responders.
Study Type
INTERVENTIONAL
Allocation
NON_RANDOMIZED
Purpose
DIAGNOSTIC
Masking
NONE
Enrollment
63
Participants will receive a loaner Apple Watch with the Walk.Talk.Track. (WTT, produced by PHaware) app downloaded. Participants will perform a daily 6MWT at home using the Apple Watch and WTT app. They will undergo a history and physical, blood draw, echocardiogram and in-clinic 6MWT at the baseline and 12-week follow up visit.
Stanford University
Stanford, California, United States
App/watch recorded and in-clinic recorded six minute walk distance (6MWD)
App/watch recorded and in-clinic recorded 6MWD will be compared by Bland Altman graph and will be considered interchangeable if the line of equality lands within the 95% confidence interval of the mean difference
Time frame: 12 weeks
Count of participants with an increase of >32 meters in 6MWD from baseline as a measure of time to response to therapy
Hazard ratios will be calculated at two week intervals to evaluate for between group differences
Time frame: 12 weeks
Count of participants with an increase of >3bpm in heart rate recovery at one minute (HRR1) from baseline as a measure of time to response to therapy
HRR1 is calculated as peak heart rate (pHR) - HR one minute into recovery period. Hazard ratios will be calculated at two week intervals to evaluate for between group differences
Time frame: 12 weeks
Count of participants with a decrease of >5bpm in resting HR from baseline as a measure of time to response to therapy
Hazard ratios will be calculated at two week intervals to evaluate for between group differences
Time frame: 12 weeks
Count of participants with an increase of >5ms in heart rate variability (HRV) from baseline as a measure of time to response to therapy
HRV will be calculated as the standard deviation of R wave to R wave intervals (SDNN) over the 2 minute period following exercise. Hazard ratios will be calculated at two week intervals to evaluate for between group differences
Time frame: 12 weeks
Count of participants with an increase of >5% in chronotropic index (CI) from baseline as a measure of time to response to therapy
CI will be calculated as (actual peak HR - resting HR)/(Age predicted peak HR \[220-age\] - resting HR). Hazard ratios will be calculated at two week intervals to evaluate for between group differences
Time frame: 12 weeks
Within the treatment arm, count of participants with an increase of >3bpm in heart rate recovery at one minute (HRR1) from baseline when comparing medication responders vs non-responders
Medication responders will have a ≥32m improvement in 6MWD at 12 weeks; non-responders will have \<32m improvement. Hazard ratios will be calculated at two week intervals to evaluate for between group differences
Time frame: 12 weeks
Within the treatment arm, count of participants with a decrease of >5bpm in resting HR from baseline when comparing medication responders vs non-responders
Medication responders will have a ≥32m improvement in 6MWD at 12 weeks; non-responders will have \<32m improvement. Hazard ratios will be calculated at two week intervals to evaluate for between group differences
Time frame: 12 weeks
Within the treatment arm, count of participants with an increase of >5ms in heart rate variability (HRV) from baseline when comparing medication responders vs non-responders
Medication responders will have a ≥32m improvement in 6MWD at 12 weeks; non-responders will have \<32m improvement. Hazard ratios will be calculated at two week intervals to evaluate for between group differences
Time frame: 12 weeks
Within the treatment arm, count of participants with an increase of >5% in chronotropic index (CI) from baseline when comparing medication responders vs non-responders
Medication responders will have a ≥32m improvement in 6MWD at 12 weeks; non-responders will have \<32m improvement. Hazard ratios will be calculated at two week intervals to evaluate for between group differences
Time frame: 12 weeks
Between group difference in 6MWD as a measure of response to the intervention
A two-sample T-test will be performed on the delta change in 6MWD (week 12 - baseline / baseline) x100\]) between the treatment and control groups and a p-value will be calculated from this data.
Time frame: 12 weeks
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.