HFpEFAPAVENCT07270536
Accelerated Pacing and Cardiac Filling Pressures During Exercise in Patients With Heart Failure With Preserved Ejection Fraction
A study testing Accelerated pacing with AV-delay optimization during rest and light intensity cycling in people with HFpEF, run by Universitaire Ziekenhuizen KU Leuven at 2 sites in Belgium.
Trial summary
What is HFpEF? In heart failure with preserved ejection fraction (HFpEF), the heart pumps well but struggles to relax and fill with blood between beats. This raises the pressure inside the heart, especially during physical activity, causing symptoms like shortness of breath and fatigue - even with light activities… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- HFpEF
- What is being tested?
- Accelerated pacing with AV-delay optimization during rest and light intensity cycling
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 20 participants
- Where
- 2 sitesBelgium
- Study dates
- 10 Dec 2025to 1 Mar 2027
- Phase
- Interventional
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
Participants eligible for inclusion in this study must meet all of the following criteria:
- Voluntary written informed consent of the participant has been obtained prior to any screening procedures
- At least 18 years of age at the time of signing the Informed Consent Form (ICF)
- Heart failure with preserved ejection fraction, defined as one of the below criteria:
- EF >= 45% and HFA-PEFF score >= 5 (Heart Failure Association-Pre-test assessment, Echocardiography and natriuretic peptide, Functional testing, Final etiology; heart failure association of the European Society of Cardiology and the Heart Failure Association (34))
- EF >= 45% and H2FPEF score >= 6 (Heavy, Hypertensive, Atrial fibrillation, Pulmonary hypertension, Elder, Filling pressure; Mayo Clinic group (35)))
- EF >= 45% and
- History of heart failure hospitalization after pacemaker implantation or ii.On loop-diuretics at time of inclusion
- Having a DDD-pacemaker with LBB area pacing, implanted at least 12 weeks before iCPET
- >=6 weeks on optimal HFpEF therapy (MRA and SGLT2i) at time of iCPET, unless contraindicated or not tolerated
- Sinus rhythm at time of screening and iCPET
Participants eligible for this Study must not meet any of the following criteria:
- Participant has a history of:
- Evidence of significant pulmonary comorbidity based on abnormal pulmonary function tests (FEV1 <60%) or aberrant lung parenchyma more than mild on radiological imaging
- Severe/symptomatic valvular diseases
- Severe pulmonary hypertension (PASP > 55mmHg estimated by Doppler Echo)
- Unstable arrhythmias (VT, VF)
- Recurrent syncopes after pacemaker implantation
- Permanent atrial fibrillation
- Amyloid cardiomyopathy
- Physical inability to perform exercise
- More than 1 hospitalization for heart failure in the last year
- Resting heart rate> 100bpm
- At time of iCPET or inclusion: decompensated heart failure, unstable coronary syndrome
- Contraindication to central venous access
- Severe coagulopathy (e.g., spontaneous INR > 2, thrombocytopenia < 50,000/µL)
- Local infection or skin infection at the insertion site
- Thrombosis or anatomical abnormalities of the right jugular vein
- Pneumothorax or contralateral lung pathology
- Inability to properly position the patient
- Contraindication to arterial access
- Thrombosis or occlusion of the target artery
- Raynaud's phenomenon or other vasospastic disorders
- Active infection at the intended insertion site
- Severe coagulopathy (e.g., spontaneous INR > 2, thrombocytopenia < 50,000/µL)
- Insufficient collateral circulation (e.g., inadequate perfusion in an Allen test)
- Contraindications to CPET
- ECG signifying myocardial injury
- ECG signifying current or potentially lethal arrhythmias
- Systemic hypotension (e.g. systolic blood pressure < 90 mmHg)
- Extreme hypertension (e.g. systolic blood pressure > 220 mmHg)
- Syncope, presyncope, or lightheadedness
- SaO2 < 88%
- Severely elevated PCWP (> 40 mmHg) during exercise
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
Belgium2 sites, 2 recruiting
- Recruiting
Jessa Ziekenhuis Hasselt
Hasselt, 3500
Jan Verwerft, MD PhD, jan.verwerft@jessazh.be
Jan Verwerft, MD PhD
- Recruiting
University Hospitals Leuven
Leuven, 3000
Margot Vermeiren, MD, +3216332211, margot.vermeiren@kuleuven.be
margotvermeiren97@gmail.com
About this study
Official title: The Impact of Accelerated Pacing and AV-delay Regulation on the Pulmonary Capillary Wedge Pressure During Exercise in Patients With HFpEF
What is HFpEF? In heart failure with preserved ejection fraction (HFpEF), the heart pumps well but struggles to relax and fill with blood between beats. This raises the pressure inside the heart, especially during physical activity, causing symptoms like shortness of breath and fatigue - even with light activities like walking or climbing stairs.
What is this study about? Recent research suggests that a higher heart rate may help lower this elevated pressure. Many HFpEF patients already have a pacemaker. This study investigates whether simply increasing the pacemaker rate during light exercise can reduce the pressure in the heart.
Read more
How does the study work? We wille measure heart pressures in 20 patients in rest and while cycling using a heart catheter and monitor their breathing. Throughout these measurements, we will gradually increase the pacemaker rate step by step.
Why does this matter? If a higher pacemaker rate successfully lowers heart pressure, this could offer a simple, drug-free way to improve daily functioning and comfort for thousands of patients with HFpEF, justifying further long-term studies to evaluate effects beyond the immediate changes in heart pressures.
Read the detailed description
First, we will review patient records to identify eligible participants, who will then be contacted during their regular check-up visit. If they are interested in participating, they will be invited for an additional screening visit if needed.
Patients who meet the eligibility criteria will be invited for an invasive exercise test. At this visit, two small tubes (catheters) will be placed, one in a neck vein and one in a wrist artery, to measure heart pressures and blood oxygen levels. The patient then sits on a reclined stationary bike, wearing a breathing mask to monitor oxygen uptake. Throughout the visit, ultrasound measurements of the heart will also be performed.
First, heart pressures are measured at rest while the pacemaker rate is gradually increased in three steps (+20, +40, +60 beats per minute). Second, the patient cycles gently while the same measurements are repeated, with the pacemaker rate increased in three steps (+10, +30, +50 beats per minute). In a final step of both the rest and exercise protocol, the heart rate will return to the level associated with the lowest heart pressure, and blood oxygen levels will be checked, allowing the research team to calculate how many liters of blood the heart pumps per minute. Afterward, the catheters are safely removed and the pacemaker settings are restored to their original values. This visit is expected to last about three hours, after which study participation ends.
The full study is expected to be completed once 20 patients have finished all study tests.
- Conditions
- HFpEF
- Being tested
- Accelerated pacing with AV-delay optimization during rest and light intensity cycling
- Keywords
- Heart Failure with Preserved Ejection Fraction, Accelerated pacing, Chronotropic response, Hemodynamics
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Accelerated pacing with AV-delay optimization during rest and light intensity cyclingOther
Patients will undergo one resting and one exercise protocol (25 Watts). During each protocol, the pacemaker rate will be gradually increased in three stages: +20, +40, +60 bpm at rest and +10, +30, +50 bpm during exercise. At each stage, intracardiac pressures and shear-wave velocity will be measured. In a final fourth stage, the pacemaker rate returns to the level associated with the lowest filling pressure, after which blood oxygen levels and oxygen uptake are assessed to calculate cardiac output.
| Study group | Role | What they receive |
|---|---|---|
| All patients | Experimental | Not described Receives: Other: Accelerated pacing with AV-delay optimization during rest and light intensity cycling |
What is being measured
The primary outcome is the main question the study is designed to answer.
Pulmonary capillary wedge pressure (PCWP), measured using a Swan-Ganz catheter (pulmonary artery catheter).
The change in PCWP at each pacing frequency (+20 bpm, +40 bpm, +60 bpm) with its corresponding optimal AV-delay at rest, compared to baseline PCWP.
The change in PCWP at each pacing frequency (+10 bpm, +30 bpm, +50 bpm) using dynamic AV-delay programming, while avoiding truncation, compared to baseline PCWP during exercise (cycle ergometry at 25 W) Baseline PCWP is calculated as the average of the measurements before and after each accelerated pacing-on step, using the intrinsic HR or baseline atrial pacing rate as the reference HR, as applicable
Measured: Intraprocedural
Secondary outcomes (4)
Cardiac output, measured using the direct Fick principle
The change in CO, measured by the direct Fick principle, at the pacing frequency corresponding to the greatest reduction in PCWP compared to the reference HR at rest and during exercise (cycling at 25 Watts)
Measured: Intraprocedural
Shear wave velocity, measured via echocardiographically obtained myocardial shear waves following mitral valve closure
The change in shear wave velocity (SWV) at each pacing rate compared to the reference heart rate at rest and during exercise (cycling at 25 Watts) The shear wave velocity at the reference heart rate is defined as the average of the SWV at the reference heart rate heart rate before and after each pacing step.
Measured: Intraprocedural
Peripheral oxygen extraction
The change in peripheral oxygen extraction, measured by the oxygen uptake divided by the cardiac output, at the pacing frequency corresponding to the greatest reduction in pulmonary capillary wedge pressure compared to peripheral oxygen extraction at the reference heart rate at rest and during exercise (cycling at 25 Watts)
Measured: Intraprocedural
Stroke volume
The change in stroke volume, measured by the cardiac output divided by the heart rate, at the pacing frequency corresponding to the greatest reduction in pulmonary capillary wedge pressure compared to stroke volume at the reference heart rate at rest and during exercise (cycling at 25 Watts)
Measured: Intraprocedural
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Dec 2025
- Study start10 Dec 2025
- Primary completion1 Mar 2027 (estimated)
- Study completion1 Mar 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for HFpEFStudies of the same condition, open and under way.
- More trials run by Universitaire Ziekenhuizen KU LeuvenThe sponsor's other registered studies.
- 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
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 20 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Universitaire Ziekenhuizen KU Leuven
- Sponsor type
- University, hospital or other
- Collaborators
- Hartcentrum Hasselt
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07270536
- Sponsor's protocol ID
- S70922
- Acronym
- APAVE
- Status last verified
- Nov 2025
- First submitted
- 14 Nov 2025
- Last updated
- 5 Jun 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: IPD will not be shared due to privacy considerations and participant confidentiality.