Each time a subject's thoracic fluid index (TFI) exceeded a threshold for 3 consecutive days, a data update report was generated by the uCor management system. The site then confirmed its receipt of the data update by completing a case report form. At least 1 of these case report forms was completed for 56 subjects.

data updates per subject

Sites reviewed data reports in each of the following contexts: planned weekly phone call, planned office visit, unplanned phone call, unplanned office visit, and data update. Sites reported whether they spent less than 5, 5 to 10, or greater than 10 minutes reviewing each report. At least 1 of these case report forms was completed for 214 subjects.

Sites reviewed data reports in each of the following contexts: planned weekly phone call, planned office visit, unplanned phone call, unplanned office visit, and data update. Sites reported whether they spent less than 5, 5 to 10, or greater than 10 minutes reviewing each report. At least 1 of these case report forms was completed for 214 subjects.

Most common amount of time spent reviewing by each site

Sites reviewed data reports in each of the following contexts: planned weekly phone call, planned office visit, unplanned phone call, unplanned office visit, and data update. In each context, the subject was asked whether their symptoms changed. If yes, the site reported in a case report form whether it took action to treat the subject in the form of a medication change or lifestyle modification. At least one of these case report forms (CRFs) was completed for 214 subjects

Number of medication changes or lifestyle modifications per subject based on μCor data and symptoms

Sites reviewed data reports in each of the following contexts: planned weekly phone call, planned office visit, unplanned phone call, unplanned office visit, and data update. In each context, the subject was asked whether their symptoms changed. If yes, the site reported in a case report form whether it took action to treat the subject in the form of a medication change or lifestyle modification. At least one of these case report forms (CRFs) was completed for 214 subjects.

Number of subjects with medication changes based on μCor data and symptoms

Sites reviewed data reports in each of the following contexts: planned weekly phone call, planned office visit, unplanned phone call, unplanned office visit, and data update. In each context, the subject was asked whether their symptoms changed. If yes, the site reported in a case report form whether it took action to treat the subject in the form of a medication change or lifestyle modification. At least one of these case report forms (CRFs) was completed for 214 subjects

Number of subjects with lifestyle modifications based on μCor data and symptoms

During weekly planned phone calls, planned office visits, and unplanned office visits, sites asked subjects whether they underwent any changes to their heart failure and/or cardiac medications since the last phone call and reported the result in a case report form. At least 1 of these case report forms was completed for 241 subjects.

Subjects with Medication Changes (MC) based on incidental findings

482 medication changes or lifestyle (MC/LS) modifications occurred within the first 90 days of the study. To include only medication changes preceded and followed by sufficient µCor data to determine a threshold crossing, medication changes within the first 2 weeks of the study or the final 3 weeks of device wear were discarded. This resulted in in 262 analyzable changes. Changes occurring within 1 week of another change were grouped together. This resulted in 192 change events. Time windows were defined as 0-13 days before the first change in a change event vs. 8-21 days after the last change in a change event. A high μCor measurement was defined as the receipt of a data update by the site. A low μCor measurement was defined as the absence of a data update received by the site.

MC/LS events preceded by a high uCor measurement within -13 to 0 days

Definitions:

Daytime: 7:00 AM - 12:00 AM Nighttime: 12:00 AM - 7:00 AM

For each day on which the subject wore the device, the following values were calculated:

Daytime activity: The proportion of minutes while wearing the device that the subject spent active (unitless).

Nighttime heart rate: The median heart rate while wearing the device during the night (beats/min) Thoracic fluid index: The median proportion of ratio of radiofrequency-measured lung fluid readings compared to the subject's baseline (unitless).

Nighttime posture: The median pitch angle while wearing the device during the night (degrees, where 0 is the horizontal).

Nighttime respiration: The median respiration rate while wearing the device during the night (breaths/min)

HF event: a hospitalization, emergency room visit, observation unit visit, unplanned clinic visit, or death primarily due to heart failure.

The median was calculated for the 7 days prior to the 1st heart failure (HF) event; the median was calculated for the final 7 days of device wear. ROC analysis was performed. Data are presented assuming that the device reading in subjects without events is less than that of subjects with events. Unit of measure: probability that a randomly chosen subject with severe symptoms has a greater device value than a randomly chosen subject with mild symptoms.

During office visits at months 1, 2, and 3, subjects reported their degrees of dyspnea, orthopnea, and fatigue on the following scale: [none, seldom, frequent, continuous]. Each day that the subject wore the device, a daily median was calculated for the following measures: [thoracic fluid index, nighttime heart rate, nighttime respiration rate]. Nighttime was defined as 12:00 AM - 7:00 AM.

The median of the daily medians for each device measure was calculated for the 7 days preceding each office visit. To assess whether reports of severe [frequent or continuous] symptoms were associated with greater device measures than reports of mild symptoms [none or seldom], ROC analysis was performed. Unit of measure: probability that a randomly chosen subject with severe symptoms has a greater device value than a randomly chosen subject with mild symptoms.

During office visits at months 1, 2, and 3, subjects reported their degrees of dyspnea, orthopnea, and fatigue on the following scale: [none, seldom, frequent, continuous].

Each of the 249 participants in the study could contribute data to either Arm/Group depending on the severity of their symptoms across the 3-month study duration.

For each weekly phone call and monthly office visit, each subject reported whether they experienced a hospitalization or emergency room visit since their last call/visit. An adjudication committee of physicians determined whether each event was due to HF or not.

Subjects who had hospital readmission, physician visit, and/or outpatient clinic visit during the study period

On each subject's final date of study participation, their survival status was recorded.

Descriptive statistics around mortality rate, cause of death, quality of life (QoL), and health care utilization among patients six months and one year after enrollment into the study.

On each subject's final date of study participation, in the case of death, the cause of death was recorded.

Descriptive statistics around mortality rate, cause of death, quality of life (QoL), and health care utilization among patients six months and one year after enrollment into the study.

At 0 months, 6 months, and 1 year after enrollment, subjects completed a Kansas City Cardiomyopathy Questionnaire (KCCQ-12). Quality of life is calculated as:

KCCQ12-QL = 100*[(average of Questions 6 and 7) - 1]/4 Score is scaled 0-100, where 0 denotes the lowest reportable health status and 100 the highest.

Descriptive statistics around mortality rate, cause of death, quality of life (QoL), and health care utilization among patients six months and one year after enrollment into the study.

For each weekly phone call, monthly office visit, 6-month phone call, and 1-year phone call, each subject reported whether they experienced a hospitalization, emergency room visit, or unplanned doctor's office visit since their last call/visit.

All subjects in the study from the timepoint of enrollment until end of study participation.