Chemoreflex Gain on Exercise

The purpose of this study is to assess chemoreflex gain on exercise.

Study Overview

• Status: Unknown
• Conditions: Exertional Periodic Breathing
• Intervention / Treatment: Other: carbon dioxide

Detailed Description

Normally breathing is controlled by a reflex that responds to the levels of carbon dioxide (CO2) in the blood. The change in breathing that results from a change in the blood's CO2 concentration is called the chemoreflex.

In heart failure, a condition where the heart muscle is damaged and can not pump as well, this reflex is exaggerated. The result of this can be breathing conditions characterised by patients hyperventilating at times and at other times taking very shallow breaths or even stopping altogether. In the past the only way of measuring this chemoreflex was to get patients to breathe into a large container and to rebreathe their exhaled air and allow the CO2 to rise over time, whilst keeping the oxygen constant. The proportion by which the ventilation increases with increasing carbon dioxide is the chemoreflex gain. Unfortunately, because this test takes a long time to conduct, requires specialist knowledge and equipment it has not been possible to measure this reflex on exercise.

• Study Type: Interventional
• Enrollment (Anticipated): 20
• Phase: Phase 1

Contacts and Locations

Study Locations

• United Kingdom
  • London
    • Paddington, London, United Kingdom, W2 1LA
      • Recruiting
      • St Mary's Hospital
      • Contact: Resham Baruah, MBBS; Phone Number: 02075941027; Email: resham.baruah@imperial.ac.uk
      • Principal Investigator: Darrel P Francis, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Volunteers: Males aged 18-80 years who are able to perform both running and cycling and can follow simple visual instructions.
• Heart Failure Subjects: Males aged 18-80 with a clinical diagnosis of heart failure who are able to perform both running and cycling and can follow simple visual instructions.

Exclusion Criteria:

• Chest pain of any cause within 4-6 days,
• Pulmonary oedema,
• Uncontrolled hypertension (systolic blood pressure > 220 mm Hg, diastolic >120 mm Hg),
• Severe aortic stenosis,
• Severe hypertrophic obstructive cardiomyopathy,
• Untreated life threatening arrhythmia,
• Dissecting aneurysm,
• Recent surgery (within 4-6 weeks), COPD.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
chemoreflex gain on exercise	every minute

Secondary Outcome Measures

Outcome Measure	Time Frame
Reproducibility of chemoreflex gain on exercise	every minute

Collaborators and Investigators

• Sponsor: Imperial College London

Study record dates

Study Major Dates

• Study Start: February 1, 2010
• Primary Completion (Anticipated): October 1, 2010
• Study Completion (Anticipated): October 1, 2010

Study Registration Dates

• First Submitted: January 13, 2010
• First Submitted That Met QC Criteria: January 14, 2010
• First Posted (Estimate): January 15, 2010

Study Record Updates

• Last Update Posted (Estimate): April 19, 2010
• Last Update Submitted That Met QC Criteria: April 16, 2010
• Last Verified: April 1, 2010

More Information

Terms related to this study

• Keywords: chemosensitivity
• Additional Relevant MeSH Terms: Pathologic Processes; Respiratory Tract Diseases; Respiration Disorders; Respiratory Aspiration
• Other Study ID Numbers: 10/H0712/9

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No