An interventional study of Individualized myPACE pacemaker programming in Heart Failure and Preserved Ejection Fraction, Heart Failure New York Heart Association Class III and Heart Failure New York Heart Association (NYHA) Class II, sponsored by Tufts Medical Center. Not yet recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-08.
Sponsored by Tufts Medical Center · Not applicable, Interventional, and Treatment
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.
180 studies on the registry are indexed under Heart Failure, Diastolic; 38 are open to participants now.
This study's planned enrollment of 36 is below the median of 49 across 126 interventional studies indexed under Heart Failure, Diastolic.
Browse Heart Failure, Diastolic studies →Tufts Medical Center is the lead sponsor of 195 studies on the registry; 29 are open to participants now.
Of its 30 completed or terminated interventional studies of FDA-regulated products, 16 (53%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
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.
Device: Individualized myPACE pacemaker programming
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.
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.
Time frame: Baseline, 12 months
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).
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: Baseline, 12 months
NTproBNP
NTproBNP level change from baseline to 12 months
Time frame: Baseline, 6 months, 12 months, 15 months
Minnesota Living with Heart Failure Questionnaire Score
Change in MLHFQ total score from conventional pacing at 60 bpm to personalized physiologic pacing (myPACE).
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: Through 18 months
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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