A Phase 2/3 interventional study of Closed loop stimulation and Standard rate response in Congenital Heart Disease and Bradycardia Sinus, sponsored by University of California, Los Angeles. Terminated at 1 site in United States. Open to participants aged 14 Years to 65 Years. Per ClinicalTrials.gov, last updated 2023-01-20.
Sponsored by University of California, Los Angeles · Phase 2/3, Interventional, and Treatment
Among 356 studies in Heart Defects, Congenital with a site in United States — 66 open to participants now, 87 under way, 4 of them phase 3. Heart Defects, Congenital · United States.
Among the 356 studies in Heart Defects, Congenital with a site in United States, this one is the 167th largest by enrollment of the 184 interventional ones that give a count, is one of 19 that started in 2021, is one of 6 in phase 2/3, and was the 212th registered.
991 studies on the registry are indexed under Heart Defects, Congenital; 251 are open to participants now.
Browse Heart Defects, Congenital studies →66 of the 356 studies in Heart Defects, Congenital with a site in United States are open now. Recruiting first, the newest first:
University of Nebraska · Sites in United States
Le Bonheur Children's Hospital · Sites in United States
Carelon Research · Sites in United States
Carelon Research · Sites in United States
The Cleveland Clinic · Sites in United States
A study can be open while its sites in United States have not opened yet or have stopped. Only those recruiting at a site in United States →
Of the 154 Heart Defects, Congenital studies recruiting now, 67 (44%) set no upper age limit and 79 (51%) stop at 75 or younger; 110 take children under 18; 25 take healthy volunteers.
This study: 14 Years to 65 Years · all sexes · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
356 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 22 · Phase 2 33 · Phase 3 25 · Phase 4 9
First in 1980; this study’s year is marked. 19 started in 2021.
This study's enrollment of 4 is below the median of 60 across 507 interventional studies indexed under Heart Defects, Congenital.
Median enrollment 50 across the 184 interventional studies, 72 across the 167 observational. Of the 240 that completed or were terminated, 62 (26%) have results posted.
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31 of 356 have an industry lead sponsor. The 10 most frequent:
University of California, Los Angeles is the lead sponsor of 1,170 studies on the registry; 195 are open to participants now.
Of its 95 completed or terminated interventional studies of FDA-regulated products, 70 (74%) have results posted.
University of California, Los Angeles has 6 studies filed under Heart Defects, Congenital — fewer than ten, so there is no comparison to draw.
30 of the studies in Heart Defects, Congenital with a site in United States that are under way reach primary completion within a year, 1 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT04216927Phase 3Children's Hospital Medical Center, CincinnatiNO During CPB in Neonates to Reduce Risk of AKI | 2027-06-30 |
| NCT05077774Medtronic CardiovascularHarmony TPV Post-Approval Study | 2026-11 |
| NCT05687292Boston Children's HospitalApplication of a Clinical Decision Support System to Reduce Mechanical Ventilation Duration After Cardiac Surgery in Children | 2026-11-18 |
| NCT07559253University of Wisconsin, MadisonImplementation of an Accessible Healthcare Model (ACHD STRONG): Comparing Nurse and Physician Lead Healthcare Transition Education in a RE-AIM Framework | 2026-11-30 |
| NCT04236479Catherine BollardMesenchymal Stromal Cells for Infants With Congenital Heart Disease (MedCaP) | 2026-12 |
Among the 356 studies in Heart Defects, Congenital with a site in United States, from their registry updates:
This tab as a report to print or save as PDF → With an account.
The closed-loop stimulation (CLS) algorithm is a novel sensor-based technology that relies on the change in myocardial systolic impedance for modulation of the heart rate during physical and emotional stress.3 The pacing algorithm has been shown to be highly effective for a wide range of clinical scenarios. Despite the fact that congenital heart disease (CHD) patients are likely to derive significant benefit in terms of functional ability and aerobic capacity using this novel technology, the CLS system has not been adequately studied in this population. As many CHD patients also undergo epicardial placement of pacing systems at the time of concomitant cardiac surgery, CLS has been less often utilized in this population given almost no data in the setting of surgical electrode placement. The present study intends to examine the benefits of the CLS algorithm in the CHD population, employing the use of epicardial pacemaker systems in the study protocol.
Sinus node dysfunction is highly prevalent among patients with congenital heart disease, manifesting as resting bradycardia or chronotropic incompetence. As children and adults with congenital heart disease are now expected to have increasing life-expectancy; with well over 1 million adult patients currently living in North America,1 issues such as mental health, acquired comorbidities and their impact on overall cardiovascular health have assumed increased scrutiny.
It is now understood that objective measures of aerobic capacity, such as peak VO2, peak VE/VCO2, and heart rate reserve predict all-cause mortality for adult patients with congenital heart disease. As the chronotropic response during exercise is a key determinant of aerobic capacity, improvement in sensor-based technology for heart rate support is expected to have a significant impact on functional capacity and longevity in this population. Some forms of congenital heart disease, such as single ventricle physiology after the Fontan population are especially likely to benefit, as cardiac output is determined almost exclusively by heart rate during exertion due to limited ability to augment cardiac stroke volume.2
It is also becoming increasingly clear that sedentary behaviors are highly relevant to overall cardiovascular health in the general adult population. Adult patients with congenital heart disease are at especially high risk for sedentary behavior as a result of 1) chronic restriction for physical activities based on ill-founded medical advice, 2) chronotropic incompetence resulting from prior surgical palliations and hemodynamic stressors, and 3) overestimation of physical activity.
5.0 Enrollment/Randomization
Patient Enrollment: The treating physician will identify potential subjects with a previously implanted pacemaker and present a brief overview of the study; if the subject is interested, the study will be described in detail. Informed consent will be obtained by the investigator after discussing the study, including the voluntary nature of participation and notification the subject can withdraw at any time. Ample time for questions and answers will be allowed. The investigator will give the subject and his/her legal guardian the opportunity to take the consent home to think about it more, with the option to call or meet with the investigator to ask additional questions. If the subject and/or his/her parent/legal guardian agree to participate, the investigator will ask them to sign a written, informed consent and assent. A copy of the assent and consent will be given to the subject and/or his/her parent/legal guardian.
Randomization Procedure: This will be a single-blind placebo-controlled randomized crossover study with 2 treatments: CLS-on versus CLS-off (accelerometer only). Each enrolled patient will receive both treatments for 3 months. The order of treatments will be randomized 1:1.
Randomization
There will be a 50:50 randomization, with half the subjects randomized to CLS-on then CLS-off, and half randomized to CLS-off then CLS-on.
Subjects previously receiving rate-responsive pacing with CLS that are randomly selected to CLS-on will continue with the identical programmed parameters. For subjects not previously receiving rate-responsive pacing with CLS that are randomly selected to CLS-on nominal programming will be utilized with a base rate of 60 beats per minute.
Subjects will then initiate treatment A (CLS-on or CLS-off) in a blinded fashion. At 3 months, subjects will undergo testing.
After 3 months of treatment A, subjects will be reprogrammed to treatment B. Tracking of physical activity with the device accelerometer will continue during this period. After 3 months of treatment B, repeat testing will be repeated.
Patients will be followed during both treatment phases per usual clinical routine. Patients who experience significant symptoms (extreme fatigue, debilitating palpitations, or other clinically relevant symptoms) will be evaluated by their treating physician. Subjects that have any adverse events during treatment A will discontinue treatment A and immediately crossover to treatment B. Subjects with events during treatment B will be removed from the study and unblinded. Further treatment will be determined by the treating physician.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Congenital heart disease
Significant sinus node dysfunction
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Subjects in this arm will be programmed to CLS-on to received closed loop stimulation-based pacing for 3 months, followed by a standard rate response for 3 months.
Device: Closed loop stimulation · Device: Standard rate response
Subjects in this arm, will be placed in a standard rate response for 3 months, followed by CLS-on to received closed loop stimulation-based pacing for 3 months.
Device: Closed loop stimulation · Device: Standard rate response
Closed loop stimulation is a physiologic, rate-adaptive pacing algorithm.
Standard rate response is an algorithm to increase heartrate based on movement
Number of Participants With Blunted or Unchanged Effect of Mental Stress on Heart Rate
Heart rate in response to mental stress during each intervention; a math test was performed during autonomic testing
Time frame: 3 months after the start of each intervention, a total of 6 months
Heart Rate Response During a 48-hour Assessment Period
Average heart rate as measured by Holter monitor for 48 hours during each intervention
Time frame: 3 months after the start of each intervention, a total of 6 months
Average Oxygen Consumption During Each Intervention
Oxygen uptake as determined by cardiopulmonary gas exchange during a stress test under 4 conditions: Sitting/standing 60 seconds Kettlebell walking 110 seconds Stairs 176 seconds Sweeping 62 seconds
Time frame: 3 months after the start of each intervention, a total of 6 months
Quality of Life as Assessed by SF-36
Quality of life as assessed by SF-36 questionnaire following each period of intervetion. SF- 36 investigates the standard of quality of life through a general health assessment and not specific to a particular disease, age or treatment group. It is a 36-item questionnaire measuring 8 domains \[physical functioning, role limitations due to physical health (role physical), bodily pain, general health, energy, social functioning, role limitations due to emotional health (role emotional), and emotional wellbeing\]. Each domain score ranges from 0 (worst) to 100 (best), with higher scores reflecting better health-related functional status.
Time frame: 3 months after the start of each intervention, a total of 6 months
| Milestone | CLS-On Followed by CLS-Off | CLS-Off Followed by CLS-On |
|---|---|---|
| Started | 2 | 2 |
| Completed test period 1 completed | 1 | 1 |
| Test period 2 begun | 1 | 1 |
| Completed | 1 | 1 |
| Not completed | 1 | 1 |
| Withdrew: Received heart transplant | 1 | 0 |
| Withdrew: Pacemake replacement | 0 | 1 |
Heart rate in response to mental stress during each intervention; a math test was performed during autonomic testing
| Participants | CLS-On | CLS-Off (Standard Rate Response) |
|---|---|---|
| Heart rate blunted | 1 | 0 |
| Heart rate unchanged | 0 | 1 |
Average heart rate as measured by Holter monitor for 48 hours during each intervention
| beats per minute | CLS-On | CLS-Off |
|---|---|---|
| Heart Rate Response During a 48-hour Assessment Period | 74 (59 to 135) | 73 (40 to 144) |
Oxygen uptake as determined by cardiopulmonary gas exchange during a stress test under 4 conditions: Sitting/standing 60 seconds Kettlebell walking 110 seconds Stairs 176 seconds Sweeping 62 seconds
| liters/minute | CLS-On | CLS-Off |
|---|---|---|
| Sitting/Standing | 1.01 | 1.04 |
| Kettlebell walking | 1.02 | 1.10 |
| Stairs | 0.82 | 0.87 |
| Sweeping | 0.78 | 0.80 |
Quality of life as assessed by SF-36 questionnaire following each period of intervetion. SF- 36 investigates the standard of quality of life through a general health assessment and not specific to a particular disease, age or treatment group. It is a 36-item questionnaire measuring 8 domains \[physical functioning, role limitations due to physical health (role physical), bodily pain, general health, energy, social functioning, role limitations due to emotional health (role emotional), and emotional wellbeing\]. Each domain score ranges from 0 (worst) to 100 (best), with higher scores reflecting better health-related functional status.
| score on a scale | CLS-On | CLS-Off |
|---|---|---|
| Physical functioning | 95 (95 to 95) | 92.5 (90 to 95) |
| Role physical | 100 (100 to 100) | 100 (100 to 100) |
| Bodily pain | 90 (90 to 90) | 85 (80 to 90) |
| General health | 67.5 (65 to 70) | 42.5 (35 to 50) |
| Energy/vitality | 47.5 (35 to 60) | 47.5 (40 to 55) |
| Social Function | 100 (100 to 100) | 100 (100 to 100) |
| Role emotional | 100 (100 to 100) | 100 (100 to 100) |
| Emotional wellbeing | 86 (84 to 88) | 84 (84 to 84) |
Collected over 3 months of each intervention. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| CLS-On | 0/4 (0%) | 0/4 (0%) | 0/4 (0%) |
| CLS-Off | 0/4 (0%) | 0/4 (0%) | 0/4 (0%) |
| Age, Categorical(Participants) | CLS-On Followed by CLS-Off | CLS-Off Followed by CLS-On | Total |
|---|---|---|---|
| <=18 years | 0 | 0 | 0 |
| Between 18 and 65 years | 2 | 2 | 4 |
| >=65 years | 0 | 0 | 0 |
| Sex: Female, Male(Participants) | CLS-On Followed by CLS-Off | CLS-Off Followed by CLS-On | Total |
|---|---|---|---|
| Female | 1 | 0 | 1 |
| Male | 1 | 2 | 3 |
| Ethnicity (NIH/OMB)(Participants) | CLS-On Followed by CLS-Off | CLS-Off Followed by CLS-On | Total |
|---|---|---|---|
| Hispanic or Latino | 0 | 0 | 0 |
| Not Hispanic or Latino | 2 | 2 | 4 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | CLS-On Followed by CLS-Off | CLS-Off Followed by CLS-On | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 0 | 0 | 0 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 0 | 0 | 0 |
| White | 2 | 2 | 4 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Region of Enrollment(participants) | CLS-On Followed by CLS-Off | CLS-Off Followed by CLS-On | Total |
|---|---|---|---|
| United States | 2 | 2 | 4 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Ran from May 2021 to primary completion in Nov 2021, 5 months.
Results were first posted in Jan 2023, 1 year 2 months after primary completion.
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This study is terminated, as verified in Dec 2022. You cannot join it, but the record below documents what was studied.
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University of California, Los Angeles →