HF Event: a hospitalization primarily due to heart failure within 90 days. Time window: The 7 days prior to the 1st heart failure hospitalization, or the final 7 days of device wear if no HF event occurred.

The median of each device value was calculated for each subject within their time window. ROC analysis was performed. Data are presented assuming that the device reading in subjects without HF events < that of subjects with HF events.

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 primarily due to heart failure

The median was calculated for the 7 days prior to the 1st hospitalization; 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 a HF event has a greater device value than a randomly chosen subject without a HF event.

Rate of occurrence of VT/VF episodes at the time of enrollment in the study and rate of occurrence of arrhythmic death in subjects at 90 days and 1 year.

Rate of occurrence of VT/VF episodes at the time of enrollment in the study and rate of occurrence of arrhythmic death at 90 days and 1 year

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 (TFI), nighttime heart rate (HR), nighttime respiration rate (RR)]. 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], receiver operating characteristic (ROC) analysis was performed. Unit of measure: probability 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 (TFI), nighttime heart rate (HR), nighttime respiration rate (RR)]. Nighttime was defined as 12:00 AM - 7:00 AM.

The results indicate the number of mild or severe symptom reports preceded by a valid device measure. Each of the 245 participants in the study could contribute data to either Arm/Group depending on the severity of their symptoms across the 3-month study duration.

During weekly phone calls and monthly office visits, subjects reported whether they experienced new arrhythmia and/or heart failure symptoms. Results indicate the number of times that subjects reported each of these two symptoms.

228 subjects completed at least one weekly phone call or monthly office visit case report form in which they could self-report arrhythmia and heart failure symptoms

During weekly phone calls and monthly office visits, subjects reported whether they experienced new arrhythmia and/or heart failure symptoms. Results indicate the median number of weeks until a subject's first symptom report of each type.

228 subjects completed at least one weekly phone call or monthly office visit case report form in which they could self-report arrhythmia and heart failure symptoms

Each subject was expected to undergo an in-person office visit at the site on months 0, 1, 2, and 3 in which they reported the severity of their heart failure symptoms. Results indicate the number of subjects reporting each severity level of each symptom at each office visit.

245 subjects were enrolled in the study. Each subject was expected to undergo an in-person office visit at the site on months 0, 1, 2, and 3 in which they self-reported heart failure symptoms. Note that this analysis includes the initial office visit (month 0).

During weekly phone calls and monthly office visits, subjects reported whether they experienced a new hospitalization since their last call/visit. An adjudication committee of physicians determined whether each hospitalization was due to HF or not.

Number of subjects hospitalized primarily for heart failure within 90 days

At the time of enrollment, subjects reported how many hospitalizations they experienced in the 90 days prior to enrollment. Results indicate the number of subjects who reported a hospitalization in this time window.

Number of subjects with a hospitalization in the 90 days prior to enrollment

At the time of enrollment, subjects reported how many hospitalizations they experienced in the 90 days prior to enrollment. Results indicate the median number of hospitalizations reported per subject in this time window.

Number of hospitalizations per subject during the 90 days prior to enrollment

During weekly phone calls, monthly office visits, the 6-month phone call, and the 1-year phone call, subjects reported whether they experienced a hospitalization, ER visit, or unplanned doctor's office visit since the last call/visit. An adjudication committee of physicians determined whether each hospitalization was due to HF or not. On each subject's final date of study participation, their survival status was recorded.

Subjects enrolled in the study at 6 months and 1 year