Trial Outcomes & Findings for The Care After Life-threatening Medical Events Study (NCT NCT04589559)

Last Updated: 2022-08-19

Results Overview

This is to assess the feasibility of enrollment in the trial. The denominator for this metric is the number of potential participants who were approached and contacted by the study team who were determined to be eligible for the study. The numerator is the number of participants who enrolled in the study (i.e., 10 participants).

Recruitment status

COMPLETED

Study phase

Target enrollment

10 participants

Primary outcome timeframe

Baseline/Visit 1

Results posted on

2022-08-19

Participant Flow

Ten participants consented to participate in the study. All participants were assigned to the intervention condition in this single-arm feasibility study.

Participant milestones

Participant milestones
Measure	Intervention: Heart Rate Variability Biofeedback Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a wrist-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Overall Study STARTED	10
Overall Study COMPLETED	10
Overall Study NOT COMPLETED	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

The Care After Life-threatening Medical Events Study

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Intervention: Heart Rate Variability Biofeedback n=10 Participants Participants in this intervention group complete at-home heart rate variability biofeedback (HRVB) training using a wrist-worn heart rate monitor and a smartphone app. They complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants are taught how to do relaxed, abdominal breathing. Second, they are taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they are taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which receives data wirelessly via Bluetooth from the heart rate monitor. Participants are instructed that their goal is to increase their HRV during the three weeks of at-home practice.
Age, Continuous	58.20 years STANDARD_DEVIATION 15.73 • n=5 Participants
Sex: Female, Male Female	3 Participants n=5 Participants
Sex: Female, Male Male	7 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	1 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	8 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	1 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	1 Participants n=5 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	2 Participants n=5 Participants
Race (NIH/OMB) White	5 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	2 Participants n=5 Participants
Sexual Orientation Straight or heterosexual	10 Participants n=5 Participants
Sexual Orientation Lesbian	0 Participants n=5 Participants
Sexual Orientation Gay	0 Participants n=5 Participants
Sexual Orientation Bisexual	0 Participants n=5 Participants
Sexual Orientation Something else	0 Participants n=5 Participants
Sexual Orientation Don't know / Not sure	0 Participants n=5 Participants
Sexual Orientation Prefer not to say	0 Participants n=5 Participants
Partner Status Single	1 Participants n=5 Participants
Partner Status Partner / Spouse	6 Participants n=5 Participants
Partner Status Separated	1 Participants n=5 Participants
Partner Status Widowed	0 Participants n=5 Participants
Partner Status Divorced	2 Participants n=5 Participants
Partner Status Prefer not to say	0 Participants n=5 Participants
Education Less than high school	0 Participants n=5 Participants
Education Some high school	0 Participants n=5 Participants
Education High school diploma/GED	0 Participants n=5 Participants
Education Trade school/Vocational school	0 Participants n=5 Participants
Education Some college	2 Participants n=5 Participants
Education College graduate	3 Participants n=5 Participants
Education Graduate school/professional school	5 Participants n=5 Participants
Education Prefer not to say	0 Participants n=5 Participants
Implanted Cardiac Device Type No cardiac device	2 Participants n=5 Participants
Implanted Cardiac Device Type Unpaced cardiac monitor	1 Participants n=5 Participants
Implanted Cardiac Device Type Implantable cardioverter defibrillator (ICD)	4 Participants n=5 Participants
Implanted Cardiac Device Type Pacemaker	2 Participants n=5 Participants
Implanted Cardiac Device Type Left ventricular assist device (LVAD)	0 Participants n=5 Participants
Implanted Cardiac Device Type Unknown or Not Reported	1 Participants n=5 Participants
Beta Blocker or Antiarrhythmic Medication Beta-Blockers	6 Participants n=5 Participants
Beta Blocker or Antiarrhythmic Medication Antiarrhythmics	0 Participants n=5 Participants
Beta Blocker or Antiarrhythmic Medication Neither Beta-Blockers nor Antiarrhythmics	1 Participants n=5 Participants
Beta Blocker or Antiarrhythmic Medication Not Reported	3 Participants n=5 Participants

PRIMARY outcome

Timeframe: Baseline/Visit 1

Population: The population studied for this metric was the set of all potential participants who were approached and contacted by the study team and determined to meet the eligibility criteria for the study.

Outcome measures

Outcome measures
Measure	Intervention: Heart Rate Variability Biofeedback n=12 Participants Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a chest-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Percentage of Eligible Cardiac Arrest (CA) Survivors Whom we Approach Who Ultimately Agree to Participate in the Pilot Study	83.33 percentage of participants who enrolled

SECONDARY outcome

Timeframe: Pre-training/Visit 2, Post-training/Visit 3 (approximately 3 weeks apart)

This is to assess successful program adherence.

Outcome measures

Outcome measures
Measure	Intervention: Heart Rate Variability Biofeedback n=10 Participants Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a chest-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Percentage of Enrolled Participants Who Complete the Pilot Study	100.0 percentage of enrolled participants

SECONDARY outcome

Timeframe: Pre-training/Visit 2, Post-training/Visit 3 (approximately 3 weeks apart)

As a measure of intervention compliance, this is to assess the percentage of participants who complete a majority (\>= 8 of 15) of the at-home HRVB sessions.

Outcome measures

Outcome measures
Measure	Intervention: Heart Rate Variability Biofeedback n=10 Participants Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a chest-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Percentage of Participants Who Complete a Majority of the At-home HRVB Sessions for the Pilot Study	60.00 percentage of enrolled participants

SECONDARY outcome

Timeframe: Post-training/Visit 3 (approximately 3 weeks)

This is to assess the intervention's feasibility. The percentage of participants who report scores \>= 4 for the feasibility total score reflects the percentage of participants who indicated that the intervention is adequately feasible.

Outcome measures

Outcome measures
Measure	Intervention: Heart Rate Variability Biofeedback n=10 Participants Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a chest-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Percentage of Participants Who Report Adequate Feasibility	90.00 percentage of enrolled participants

SECONDARY outcome

Timeframe: Post-training/Visit 3 (approximately 3 weeks)

This is to assess the intervention's acceptability. The percentage of participants who report scores \>= 4 for the acceptability total score reflects the percentage of participants who indicated that the intervention is adequately acceptable.

Outcome measures

Outcome measures
Measure	Intervention: Heart Rate Variability Biofeedback n=10 Participants Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a chest-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Percentage of Participants Who Report Adequate Acceptability	90.00 percentage of enrolled participants

SECONDARY outcome

Timeframe: Post-training/Visit 3 (approximately 3 weeks)

This is to assess the intervention's appropriateness for reducing anxiety, the proportion of participants who report scores \>= 4 would be adequate. This is to assess the intervention's appropriateness for reducing anxiety. The percentage of participants who report scores \>= 4 for the appropriateness-for-reducing-anxiety total score reflects the percentage of participants who indicated that the intervention is adequately appropriate for reducing anxiety.

Outcome measures

Outcome measures
Measure	Intervention: Heart Rate Variability Biofeedback n=10 Participants Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a chest-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Percentage of Participants Who Report Adequate Appropriateness	80.00 percentage of enrolled participants

SECONDARY outcome

Timeframe: Post-training/Visit 3 (approximately 3 weeks)

We will assess the percentage of participants who report total scores \>= 68 for their rating of the intervention's usability using the System Usability Scale.

Outcome measures

Outcome measures
Measure	Intervention: Heart Rate Variability Biofeedback n=10 Participants Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a chest-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Percentage of Participants Who Report Adequate Usability	80.00 percentage of enrolled participants

SECONDARY outcome

Timeframe: Pre-training/Visit 2, Post-training/Visit 3 (approximately 3 weeks apart)

This is to assess the Visit-2-to-3 change in cardiac-related interoceptive fear measured as the within-person difference in the sum of the four cardiac-related items from the physical subscale of the Anxiety Sensitivity Index. The total score ranges from a minimum of 0 units on a scale to a maximum of 16 units on a scale. Lower scores indicate lower anxiety.

Outcome measures

Outcome measures
Measure	Intervention: Heart Rate Variability Biofeedback n=10 Participants Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a chest-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Visit-2-to-3 Change in Cardiac-related Interoceptive Fear	-1.50 score on a scale Standard Deviation 3.03

SECONDARY outcome

Timeframe: Pre-training/Visit 2, Post-training/Visit 3 (approximately 3 weeks apart)

This is to assess the Visit-2-to-3 change in trait anxiety measured as the within-person difference in the total score of the trait version of the State-Trait Anxiety Inventory. The total score ranges from a minimum of 20 units on a scale to a maximum of 80 units on a scale. Higher scores indicate higher anxiety.

Outcome measures

Outcome measures
Measure	Intervention: Heart Rate Variability Biofeedback n=10 Participants Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a chest-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Visit-2-to-3 Change in Trait Anxiety	-6.20 score on a scale Standard Deviation 7.70

SECONDARY outcome

Timeframe: Pre-training/Visit 2, Post-training/Visit 3 (approximately 3 weeks apart)

This is to assess the Visit-2-to-3 change in trait negative affect measured as the within-person difference in the total score of the negative subscale of the Positive and Negative Affect Schedule. The total score ranges from a minimum of 10 units on a scale to a maximum of 50 units on a scale. Lower scores represent lower levels of Negative Affect.

Outcome measures

Outcome measures
Measure	Intervention: Heart Rate Variability Biofeedback n=10 Participants Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a chest-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Visit-2-to-3 Change in Trait Negative Affect	-1.90 score on a scale Standard Deviation 5.74

SECONDARY outcome

Timeframe: Up to 3 weeks (starting after Visit 2 and extending until Visit 3)

This is to assess HRV using participants' exported and deidentified data from the Elite HRV smartphone app. Specifically, HRV is operationalized as the natural log of the root mean square of the successive difference (lnRMSSD), a standard measure of beat-to-beat HRV. This HRV measure is recorded for each at-home training session completed by participants using the app and the heart rate monitor.

Outcome measures

Outcome measures
Measure	Intervention: Heart Rate Variability Biofeedback n=10 Participants Participants in this intervention group completed at-home heart rate variability biofeedback (HRVB) training using a chest-worn heart rate monitor and a smartphone app. They were asked to complete at least 10 minutes per day of HRVB training on at least 5 days per week for 3 weeks. Heart Rate Variability Biofeedback Training: First, participants were taught how to do relaxed, abdominal breathing. Second, they were taught how to breathe at a slow rate of 0.1 Hz (i.e., one completed breath cycle every 10 seconds). Third, they were taught how to monitor their heart rate variability (HRV) in real time using the smartphone app, which received data wirelessly via Bluetooth from the heart rate monitor. Participants were instructed that their goal was to increase their HRV during the three weeks of at-home practice.
Heart Rate Variability (HRV)	0.58 milliseconds Standard Deviation 1.04

Adverse Events

Intervention: Heart Rate Variability Biofeedback

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Jeffrey Birk

Columbia University Irving Medical Center

Phone: 212-342-5503

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place