Heart Failure and Preserved Ejection FractionNCT07864558
PrEcision Pacing in HFpEF: the PEP-HFpEF Trial
A study testing Individualized myPACE pacemaker programming in people with Heart Failure and Preserved Ejection Fraction and Heart Failure New York Heart Association Class III, run by Tufts Medical Center at 1 site in United States.
Trial summary
The PEP-HFpEF study is a prospective, single-center mechanistic study evaluating personalized heart rate pacing (myPACE) in patients with heart failure with preserved ejection fraction (HFpEF) and existing cardiac physiologic pacemakers. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Heart Failure and Preserved Ejection Fraction, Heart Failure New York Heart Association Class III, Heart Failure New York Heart Association (NYHA) Class II
- What is being tested?
- Individualized myPACE pacemaker programming
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 36 participants
- Where
- 1 siteUnited States
- Study dates
- Oct 2026to Sep 2029
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age ≥18 years.
- Diagnosis of heart failure with preserved ejection fraction (HFpEF), defined as left ventricular ejection fraction (LVEF) ≥50% with symptoms and signs consistent with heart failure as determined by the treating investigator.
- New York Heart Association (NYHA) Class II or III symptoms despite stable, maximally tolerated guideline-directed medical therapy.
- Pre-existing FDA-approved cardiac physiologic pacemaker (e.g., conduction system pacing or cardiac resynchronization therapy) implanted for a standard clinical indication and capable of individualized lower-rate programming.
- Expected to require ongoing pacemaker therapy throughout the study period.
- Clinically stable at enrollment, without recent major changes in heart failure status that, in the opinion of the investigator, would interfere with interpretation of study outcomes.
- Able and willing to provide written informed consent.
- Able and willing to comply with all study procedures, including pacemaker programming, cardiopulmonary exercise testing (CPET), echocardiography, blood pressure measurements, autonomic testing, blood collection, and follow-up visits.
Who cannot join
- Age <18 years.
- Left ventricular ejection fraction <50%.
- Pregnancy, breastfeeding, or women of childbearing potential unwilling to use an acceptable method of contraception during study participation.
- Inability or unwillingness to provide informed consent.
- Inability to safely perform study procedures, including CPET or autonomic testing, in the opinion of the investigator.
- Any medical condition or life expectancy that, in the opinion of the investigator, would make participation unsafe or would substantially interfere with completion of the study or interpretation of study results.
- Enrollment in another interventional clinical trial that, in the opinion of the investigators, could interfere with this study or confound interpretation of the results.
- Prisoners, wards of the state, or other individuals for whom participation would not be permissible under applicable regulations or institutional policy.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
Tufts Medical Center
Boston, Massachusetts, 02111
Courtney Uek, 617-636-4354, courtney.uek@tuftsmedicine.org
Margaret.Infeld@tuftsmedicine.org
About this study
The PEP-HFpEF study is a prospective, single-center mechanistic study evaluating personalized heart rate pacing (myPACE) in patients with heart failure with preserved ejection fraction (HFpEF) and existing cardiac physiologic pacemakers. Participants will undergo sequential periods of standard and personalized pacing with serial physiologic assessments to evaluate the effects of myPACE on exercise capacity, cardiac function, biomarkers, quality of life, and clinical outcomes.
- Conditions
- Heart Failure and Preserved Ejection Fraction, Heart Failure New York Heart Association Class III, Heart Failure New York Heart Association (NYHA) Class II
- Being tested
- Individualized myPACE pacemaker programming
- Keywords
- HFpEF, Heart Failure, pacemaker, personalized pacing, heart failure with preserved ejection fraction
- Medical subject headings
- Heart Failure, Diastolic, Heart Failure
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Individualized myPACE pacemaker programmingDevice
The myPACE intervention uses an individualized heart-rate algorithm to determine a personalized pacemaker backup rate within the normal range of adult resting heart rates. The algorithm estimates an individualized resting heart rate based on participant height and left ventricular ejection fraction (LVEF). The algorithm is designed to provide a modest increase in resting heart rate tailored to individual physiologic characteristics, including LVEF.
| Study group | Role | What they receive |
|---|---|---|
| Individualized myPACE Pacing | Experimental | Participants will undergo a 3-month baseline period with their pacemaker programmed to standard-of-care settings (lower rate limit of 60 beats per minute), followed by individualized programming using the myPACE heart-rate algorithm for 12 months. Following completion of the 12-month intervention period, pacemakers will be reprogrammed to standard-of-care settings (60 bpm) for an additional 3 months. Participants will undergo study assessments and monitoring throughout the entire 18-month study period. Receives: Device: Individualized myPACE pacemaker programming |
What is being measured
The primary outcome is the main question the study is designed to answer.
Peak Oxygen Consumption (Peak VO₂)
Change in peak oxygen consumption (peak VO2) during upright bicycle cardiopulmonary exercise testing (CPET), from conventional 60 bpm pacing (at baseline) to personalized physiologic pacing (myPACE) (at 12 months). Peak VO2 will be measured in mL/kg/min.
Measured: Baseline, 12 months
Secondary outcomes (14)
Ventilatory Efficiency (VE/VCO₂ Slope)
Change in the VE/VCO₂ slope during upright bicycle CPET from conventional pacing at 60 bpm to personalized physiologic pacing (myPACE).
Measured: Baseline, 12 months
Oxygen Pulse
Change in oxygen pulse during upright bicycle CPET from conventional pacing at 60 bpm to personalized physiologic pacing (myPACE), measured in mL/beat.
Measured: Baseline, 12 months
Arterial Elastance (Ea)
Change in arterial elastance (Ea), measured in mmHg/mL, calculated from echocardiographic measurements and non-invasive blood pressure measurements, from conventional pacing at 60 bpm at baseline to personalized physiologic pacing (myPACE) at 12 months.
Measured: Baseline, 12 months
End-Systolic Elastance (Ees)
Change in end-systolic elastance (Ees), measured in mmHg/mL, calculated from echocardiographic measurements and non-invasive blood pressure measurements, from conventional pacing at 60 bpm at baseline to personalized physiologic pacing (myPACE) at 12 months.
Measured: Baseline, 12 months
Ventriculo-Arterial Coupling (Ea/Ees Ratio)
Change in the Ea/Ees ratio, calculated from arterial elastance (Ea) and end-systolic elastance (Ees), from conventional pacing at 60 bpm at baseline to personalized physiologic pacing (myPACE) at 12 months.
Measured: Baseline, 12 months
Low-Frequency Blood Pressure Variability
Change in low-frequency blood-pressure variability during standardized autonomic nervous system testing from conventional pacing at 60 bpm at baseline to personalized physiologic pacing (myPACE) at 12 months.
Measured: Baseline, 12 months
Orthostatic Blood Pressure Recovery
Change in orthostatic blood pressure recovery during standardized autonomic nervous system testing from conventional pacing at 60 bpm at baseline to personalized physiologic pacing (myPACE) at 12 months.
Measured: Baseline, 12 months
Passive Leg Raise Response
Change in the passive-leg-raise response during standardized autonomic nervous system testing from conventional pacing at 60 bpm at baseline to personalized physiologic pacing (myPACE) at 12 months.
Measured: Baseline, 12 months
NTproBNP
NTproBNP level change from baseline to 12 months
Measured: Baseline, 6 months, 12 months, 15 months
Minnesota Living with Heart Failure Questionnaire Score
Change in total score on the Minnesota Living with Heart Failure Questionnaire (MLHFQ), a 21-item questionnaire assessing the impact of heart failure on health-related quality of life. The total score ranges from 0 to 105, with higher scores indicating worse health-related quality of life and greater impairment. Change in total score will be assessed from baseline to 12 months to evaluate the effect of personalized physiologic pacing compared with conventional pacing at 60 beats per minute.
Measured: Baseline, 12 months
Hospitalization or Invasive Outpatient Intervention for Heart Failure
Throughout the duration of the study the study team will review intercurrent clinical management events that may occur as part of the natural history and clinical management of HFpEF, including hospitalization or invasive outpatient intervention for heart failure.
Measured: Through 18 months
Heart Failure Management Events
Changes in heart failure management, including diuretic initiation, dose escalation, reduction, or discontinuation, and urgent medical visits for heart failure. Clinical events will be assessed through participant interviews and medical record review throughout study participation and formally assessed during each follow-up Assessment Window.
Measured: Through 18 months
Abnormal Heart Rhythm Management Events
Throughout the duration of the study the study team will record changes in abnormal heart rhythm management, including initiation of antiarrhythmic medication, cardioversion, ablation, urgent medical visits for abnormal heart rhythms, or hospitalization for abnormal heart rhythms. Clinical events will be assessed through participant interviews and medical record review throughout study participation and formally assessed during each follow-up Assessment Window.
Measured: Through 18 months
Serious Cardiovascular Events
Throughout the duration of the study the study team will review serious cardiovascular events, including heart attack, stroke, or death. Clinical events will be assessed through participant interviews and medical record review throughout study participation and formally assessed during each follow-up Assessment Window.
Measured: Through 18 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Oct 2026
- Study startOct 2026 (estimated)
- Primary completionMar 2029 (estimated)
- Study completionSep 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Heart Failure and Preserved Ejection FractionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 36 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Tufts Medical Center
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Margaret Infeld, MD, MS, Principal investigator, Tufts Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07864558
- Sponsor's protocol ID
- STUDY00007273: PEP-HFpEF
- Other IDs
- 26CDA1621876
- Status last verified
- Oct 2026
- First submitted
- 14 Aug 2026
- Last updated
- 29 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 29 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- PrEcision Pacing in HFpEF: the PEP-HFpEF Trial
- ClinicalTrials.gov ID
- NCT07864558
- Acronym / sponsor ID
- STUDY00007273: PEP-HFpEF
- Conditions
- Heart Failure and Preserved Ejection Fraction, Heart Failure New York Heart Association Class III, Heart Failure New York Heart Association (NYHA) Class II
- Keywords
- HFpEF, Heart Failure, pacemaker, personalized pacing, heart failure with preserved ejection fraction
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 36 participants (estimated)
- Lead sponsor
- Tufts Medical CenterUniversity, hospital or other
- Study start
- Oct 2026 (estimated)
- Primary completion
- Mar 2029 (estimated)
- Study completion
- Sep 2029 (estimated)
- First posted
- 8 Oct 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The PEP-HFpEF study is a prospective, single-center mechanistic study evaluating personalized heart rate pacing (myPACE) in patients with heart failure with preserved ejection fraction (HFpEF) and existing cardiac physiologic pacemakers. Participants will undergo sequential periods of standard and personalized pacing with serial physiologic assessments to evaluate the effects of myPACE on exercise capacity, cardiac function, biomarkers, quality of life, and clinical outcomes.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Individualized myPACE Pacing | Experimental | Device: Individualized myPACE pacemaker programmingParticipants will undergo a 3-month baseline period with their pacemaker programmed to standard-of-care settings (lower rate limit of 60 beats per minute), followed by individualized programming using the myPACE heart-rate algorithm for 12 months. Following completion of the 12-month intervention period, pacemakers will be reprogrammed to standard-of-care settings (60 bpm) for an additional 3 months. Participants will undergo study assessments and monitoring throughout the entire 18-month study period. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (8 listed)
- Age ≥18 years.
- Diagnosis of heart failure with preserved ejection fraction (HFpEF), defined as left ventricular ejection fraction (LVEF) ≥50% with symptoms and signs consistent with heart failure as determined by the treating investigator.
- New York Heart Association (NYHA) Class II or III symptoms despite stable, maximally tolerated guideline-directed medical therapy.
- Pre-existing FDA-approved cardiac physiologic pacemaker (e.g., conduction system pacing or cardiac resynchronization therapy) implanted for a standard clinical indication and capable of individualized lower-rate programming.
- Expected to require ongoing pacemaker therapy throughout the study period.
Key exclusion criteria (8 listed)
- Age <18 years.
- Left ventricular ejection fraction <50%.
- Pregnancy, breastfeeding, or women of childbearing potential unwilling to use an acceptable method of contraception during study participation.
- Inability or unwillingness to provide informed consent.
- Inability to safely perform study procedures, including CPET or autonomic testing, in the opinion of the investigator.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Individualized myPACE pacemaker programmingThe myPACE intervention uses an individualized heart-rate algorithm to determine a personalized pacemaker backup rate within the normal range of adult resting heart rates. The algorithm estimates an individualized resting heart rate based on participant height and left ventricular ejection fraction (LVEF). The algorithm is designed to provide a modest increase in resting heart rate tailored to individual physiologic characteristics, including LVEF. | Device | Individualized myPACE Pacing |
Primary outcome
Peak Oxygen Consumption (Peak VO₂)
Time frame: Baseline, 12 months
Change in peak oxygen consumption (peak VO2) during upright bicycle cardiopulmonary exercise testing (CPET), from conventional 60 bpm pacing (at baseline) to personalized physiologic pacing (myPACE) (at 12 months). Peak VO2 will be measured in mL/kg/min.
14 secondary outcomes
Ventilatory Efficiency (VE/VCO₂ Slope)
Time frame: Baseline, 12 months
Oxygen Pulse
Time frame: Baseline, 12 months
Arterial Elastance (Ea)
Time frame: Baseline, 12 months
End-Systolic Elastance (Ees)
Time frame: Baseline, 12 months
Ventriculo-Arterial Coupling (Ea/Ees Ratio)
Time frame: Baseline, 12 months
Low-Frequency Blood Pressure Variability
Time frame: Baseline, 12 months
Orthostatic Blood Pressure Recovery
Time frame: Baseline, 12 months
Passive Leg Raise Response
Time frame: Baseline, 12 months
NTproBNP
Time frame: Baseline, 6 months, 12 months, 15 months
Minnesota Living with Heart Failure Questionnaire Score
Time frame: Baseline, 12 months
Hospitalization or Invasive Outpatient Intervention for Heart Failure
Time frame: Through 18 months
Heart Failure Management Events
Time frame: Through 18 months
Abnormal Heart Rhythm Management Events
Time frame: Through 18 months
Serious Cardiovascular Events
Time frame: Through 18 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Oct 2026.
Related trials for Heart Failure and Preserved Ejection Fraction
RecruitingPhase 2
The Clinical Trial of Tamibarotene for Patients With HFpEF (RELIEF Trial)
HFpEF - Heart Failure With Preserved Ejection Fraction
RecruitingPhase 1/2
HS235 Study in Overweight and Obese Participants With Combined Pre and Post-Capillary Pulmonary Hypertension Due to Heart Failure With Preserved Ejection Fraction
Pulmonary Hypertension, Heart Failure With Preserved Ejection Fraction
RecruitingPhase 3
Maridebart Cafraglutide in Heart Failure With Preserved or Mildly Reduced Ejection Fraction and Obesity
Heart Failure With Preserved Ejection Fraction, Heart Failure With Mildly Reduced Ejection Fraction
RecruitingPhase 3
A Study to Test Whether Vicadrostat in Combination With Empagliflozin Helps People With Heart Failure
Heart Failure
Recruiting
Renal Denervation in Patients With Atrial Fibrillation and Hypertension
Atrial Fibrillation (Paroxysmal), Hypertension
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Margaret Infeld, MD, MS principal investigator
Tufts Medical Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Individualized myPACE pacemaker programming in people with Heart Failure and Preserved Ejection Fraction and Heart Failure New York Heart Association Class III, run by Tufts Medical Center at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 8 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 29 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Courtney Uek (617-636-4354, courtney.uek@tuftsmedicine.org), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Peak Oxygen Consumption (Peak VO₂) (time frame: Baseline, 12 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Oct 2026.