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Chemoreflex Gain on Exercise

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ClinicalTrials.gov Identifier: NCT01050179
Recruitment Status : Unknown
Verified April 2010 by Imperial College London.
Recruitment status was:  Recruiting
First Posted : January 15, 2010
Last Update Posted : April 19, 2010
Information provided by:

January 13, 2010
January 15, 2010
April 19, 2010
February 2010
October 2010   (Final data collection date for primary outcome measure)
chemoreflex gain on exercise [ Time Frame: every minute ]
Same as current
Complete list of historical versions of study NCT01050179 on ClinicalTrials.gov Archive Site
Reproducibility of chemoreflex gain on exercise [ Time Frame: every minute ]
Same as current
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Chemoreflex Gain on Exercise
Chemoreflex Gain on Exercise
The purpose of this study is to assess chemoreflex gain on exercise.

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.

Phase 1
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Exertional Periodic Breathing
Other: carbon dioxide
sinusoidal carbon dioxide delivery
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*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
Unknown status
October 2010
October 2010   (Final data collection date for primary outcome measure)

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.
Sexes Eligible for Study: Male
18 Years to 80 Years   (Adult, Senior)
Contact information is only displayed when the study is recruiting subjects
United Kingdom
Not Provided
Not Provided
Darrel Francis, Imperial College
Imperial College London
Not Provided
Not Provided
Imperial College London
April 2010

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP