Effect Baroreflex Activation Therapy on the Carotid Body

NCT02210923 | Unknown DMC

• 1 other identifier: NL3770006813
• Study Type: observational
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Carotid baroreflex activation therapy (BAT) by the Rheos® system produces a sustained fall in blood pressure in patients with resistant hypertension. Since the activation electrodes are implanted at the level of the carotid sinus, it is conceivable that the nearby located carotid body chemoreceptors are stimulated as well. Physiological stimulation of carotid chemoreceptors not only raises respiration, but it also increases sympathetic activity which may in part counteract the effects of BAT. The aim of the present study is to investigate whether there is evidence for concomitant carotid chemoreflex activation during BAT. We hypothesized that there is no clinically relevant co-activation of the carotid body chemoreceptors during BAT in patients with resistant hypertension.

Conditions

Hypertension Resistant To Conventional Therapy; Baroreflex; Carotid Body

Keywords

Baroreflex; Electrical stimulation; Carotid body; Chemoreceptors; Resistant hypertension

Outcome Measures

Primary Outcomes (1)

• Change in arterial CO2 (PaCO2) during baroreflex activation therapy

  During one hour several device activation settings will be programmed at random. During each device setting we will collect arterial blood samples to check for PaCO2.

  6 times during different electrical activation settings within one hour

Secondary Outcomes (7)

• Change in end-tidal CO2 during baroreflex activation therapy

  1 - 1.25 hour

• Change in blood pressure during baroreflex activation therapy

  1 - 1.25 hour

• Change in respiratory rate during baroreflex activation therapy

  1 - 1.25 hour

• Change in expiration time during baroreflex activation therapy

  1 - 1.25 hour

• Change in heart rate during baroreflex activation therapy

  1 - 1.25 hour

Study Arms (1)

Resistant hypertensive patients with Rheos system

We will program 6 electrical device activation setting twice in a random order to see what happens with the aforementioned respiratory and cardiovascular variables. The following electrical settings will be programmed for 4 minutes each setting: * 20 Hz, 3 Volts, 480 microseconds * 20 Hz, 6 Volts, 480 microseconds * 50 Hz, 3 Volts, 480 microseconds * 50 Hz, 6 Volts, 480 microseconds * 90 Hz, 3 Volts, 480 microseconds * 90 Hz, 6 Volts, 480 microseconds

Eligibility Criteria

• Age: 21 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Subjects implanted with a BAT system will be invited to participate in this study. These are patients who were enrolled in the DEBuT-HET and Rheos Pivotal Trial and have given their permission to be approached for follow-up studies. Subjects are all \>21 years of age and were all known with a blood pressure ≥160/90 mmHg despite optimal antihypertensive therapy before receiving BAT. It is essential to have the Rheos® device implanted to enable participation in this study, as we want to investigate the effect of electrical carotid sinus activation on the carotid body chemoreflex.

You may qualify if:

• Be currently implanted with Rheos system and have completed the 13-month follow-up period.
• Have at least one functional carotid baroreflex activation electrode.
• Have signed and approved informed consent form for participation in this study.

You may not qualify if:

• Myocardial infarction (MI) or cerebral vascular accident (CVA) within the past 90 days, or subject is still unstable from a prior MI or CVA that occurred more than 90 days ago.
• Are unable or unwilling to comply with the protocol requirements of this study.
• Diagnosed with severe chronic obstructive lung disease (COPD/asthma GOLD stadium III and IV).

Sponsors & Collaborators

• Maastricht University Medical Center: lead
• CVRx, Inc.: collaborator

Study Sites (1)

Maastricht University Medical Center+

Maastricht, 6229 HX, Netherlands

RECRUITING

Related Links

• Overall description of the device and related safety and efficacy results

Biospecimen

Retention: SAMPLES WITHOUT DNA

Arterial blood for analysis of PaCO2, PaO2 and pH

MeSH Terms

Conditions

Hypertension Resistant to Conventional Therapy

Study Officials

• Abraham Kroon, MD, PhD

  Maastricht University Medical Center

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Teba Alnima, MD

CONTACT

003143 3875367; teba.alnima@mumc.nl

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 4, 2014
• First Posted: August 7, 2014
• Study Start: October 1, 2013
• Primary Completion: August 1, 2014
• Last Updated: August 7, 2014

Record last verified: 2014-08

Locations

NL (1)