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Recruiting NCT04194632

NCT04194632 Right Ventricular Pacing in Pulmonary Arterial Hypertension

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Clinical Trial Summary
NCT ID NCT04194632
Status Recruiting
Phase
Sponsor University of California, San Francisco
Condition Pulmonary Artery Hypertension
Study Type INTERVENTIONAL
Enrollment 16 participants
Start Date 2021-01-01
Primary Completion 2027-01-01

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age 75 Years
Study Type INTERVENTIONAL
Interventions
Temporary right ventricular pacing

Eligibility Fast-Check

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What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

This trial targets 16 participants in total. It began in 2021-01-01 with a primary completion date of 2027-01-01.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

In pulmonary arterial hypertension (PAH), progressive pulmonary vascular remodeling leads to supraphysiologic right ventricular (RV) afterload. Pharmacologic trials have shown that aggressive upfront treatment reversing pulmonary vascular remodeling successfully increases RV function and improves survival. To date, however, there are no proven treatments that target RV contractile function. Echocardiographic studies of RV dysfunction in the setting of pressure overload have demonstrated intra and interventricular dyssynchrony even in the absence of overt right bundle branch block (RBBB). Electrophysiologic studies of patients with chronic thromboembolic disease (CTEPH) at the time of pulmonary endarterectomy have shown prolongation of action potential and slowed conduction in the right ventricle which has correlated with echocardiographic measures of dyssynchrony. Cardiac MRI measures of RV strain in patients with PAH demonstrated simultaneous initiation of RV and left ventricular (LV) contraction, but delayed peak RV strain suggesting that interventricular dyssynchrony is a mechanical rather than electrical phenomenon. Prior studies of RV dysfunction in an animal model, computer model, congenital heart disease, and CTEPH have suggested acute hemodynamic benefits of RV pacing. However, RV pacing has not been studied in patients with PAH. Furthermore, it remains unclear if pacing particular regions of the RV can achieve a hemodynamic benefit and what cost this hemodynamic improvement may incur with regards to myocardial energetics and wall stress. Therefore, the investigators propose to examine RV electrical activation in PAH, map the area of latest activation, and then evaluate the hemodynamic and energetic effects of RV pacing in these patients.

Eligibility Criteria

Inclusion Criteria: * Patients referred for a clinically indicated right heart catheterization to either diagnose pulmonary arterial hypertension prior to initiating therapies or monitor response to ongoing therapies in patients with diagnosed pulmonary arterial hypertension. * Patients with pulmonary arterial hypertension with or without significant right ventricular dysfunction as assessed by baseline echocardiography and standard of care right heart catheterization * Functional class 2 or 3 symptoms * Are able to undergo cardiac MRI, endocardial mapping, and pressure volume measurements * English speaking * All patients will be required to have evidence of right ventricular hypertrophy or conduction delay (QRS \> 130ms) on surface ECG Exclusion Criteria: * Preexisting left bundle branch block, current atrial fibrillation, or pacemaker/ defibrillators * Functional class 4 symptoms * Patients treated with parenteral or subcutaneous therapies for pulmonary hypertension * Contraindication to right heart catheterization including significant thrombocytopenia (platelets \< 50,000), coagulopathy (INR \> 1.8), or pregnancy as determined by routine screening laboratory work * Mean pulmonary artery pressure less than 25 mmHg as determined by the right heart catheterization on the day of the study procedure * Pulmonary capillary wedge pressure greater than or equal to 15 mmHg as determined by the right heart catheterization on the day of the study procedure * Severe tricuspid regurgitation as determined by baseline transthoracic echocardiogram. * Left ventricular dysfunction (EF \< 50%) as determined by baseline transthoracic echocardiogram. * Inability to complete cardiac MRI or transthoracic echocardiography * Patients with confounding systemic disease specifically portopulmonary hypertension and scleroderma associated pulmonary hypertension * Patients otherwise deemed not appropriate for the study as determined by the study investigators

Contact & Investigator

Central Contact

Benjamin Kelemen, MD

✉ Benjamin.Kelemen@ucsf.edu

📞 415-476-2143

Principal Investigator

Liviu Klein, MD

PRINCIPAL INVESTIGATOR

University of California, San Francisco

Frequently Asked Questions

Who can join the NCT04194632 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, up to 75 Years, studying Pulmonary Artery Hypertension. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

Is NCT04194632 currently recruiting?

Yes, NCT04194632 is actively recruiting participants. Contact the research team at Benjamin.Kelemen@ucsf.edu for enrollment information.

Where is the NCT04194632 trial being conducted?

This trial is being conducted at San Francisco, United States.

Who is sponsoring the NCT04194632 clinical trial?

NCT04194632 is sponsored by University of California, San Francisco. The principal investigator is Liviu Klein, MD at University of California, San Francisco. The trial plans to enroll 16 participants.

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