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Muscle Afferent Feedback Effects in Patients With Heart Failure

4. januar 2018 oppdatert av: Markus Amann, University of Utah

Muscle Afferent Feedback Effects in Patients With Heart Failure: The Development of Central Fatigue

The purpose of the study is to find out more about the mechanism by which neural feedback from the working muscle affects the development of central fatigue during exercise. Subjects with chronic heart failure (HF) and healthy subject counterparts will be tested to determine the mechanisms accounting for the premature fatigue characterizing HF patients during physical activity.

Studieoversikt

Status

Fullført

Forhold

Intervensjon / Behandling

Detaljert beskrivelse

A substantial part in limiting exercise and/or physical activity in humans results from the development of peripheral and central fatigue during physical activity. Peripheral fatigue comprises biochemical changes within the metabolic milieu of the working muscle leading to an attenuated response to neural excitation, while central fatigue comprises a failure of the central nervous system to drive motoneurons.

Patients with HF have overactive group III/IV muscle afferents and an exaggerated development of central fatigue during physical activity that is not explained by their reduced physical conditioning or cardiac insufficiency caused by their failing heart. The exact mechanisms accounting for the exaggerated central fatigue in HF remains elusive, however, the development of central fatigue during exercise has recently been linked to signaling by group III/IV muscle afferents. This makes the heightened neural feedback in HF a likely candidate for these patients' increased susceptibility to central fatigue.

Lower pH, increased lactate and increased adenosine triphosphate has been shown to activate group III/IV afferents in a physiological manner and thus induce, in a rested and unfatigued muscle, the intramuscular milieu associated with moderate to heavy exercise. The objective of this study is to quantitate and compare the sensitivity of group III/IV afferents and associated effects on central fatigue in HF patients and healthy controls when skeletal muscle is subject to controlled lower pH, increased lactate and increased adenosine triphosphate.

Studietype

Intervensjonell

Registrering (Faktiske)

144

Fase

  • Fase 1

Kontakter og plasseringer

Denne delen inneholder kontaktinformasjon for de som utfører studien, og informasjon om hvor denne studien blir utført.

Studiesteder

  • Forente stater
    • Utah
      • Salt Lake City, Utah, Forente stater, 84148
        • Veterans Affairs Salt Lake City Heath Care System
      • Salt Lake City, Utah, Forente stater, 84148
        • George E Wahlen Vetern Affairs Medical Center

Deltakelseskriterier

Forskere ser etter personer som passer til en bestemt beskrivelse, kalt kvalifikasjonskriterier. Noen eksempler på disse kriteriene er en persons generelle helsetilstand eller tidligere behandlinger.

Kvalifikasjonskriterier

Alder som er kvalifisert for studier

20 år til 79 år (Voksen, Eldre voksen)

Tar imot friske frivillige

Ja

Kjønn som er kvalifisert for studier

Alle

Beskrivelse

Heart Failure Inclusion Criteria:

  • Subjects with a history of stable cardiomyopathy (ischemic and non-ischemic, greater than 1 year duration, ages 20-79 years)
  • New York Heart Association class I through IV symptoms
  • Left ventricular ejection fraction less than 35 percent (heart failure patients with reduced left ventricular ejection fraction) or greater than 50 percent (heart failure patients with preserved left ventricular ejection fraction)
  • Sedentary, no regular physical activity for at least 6 months prior
  • Post-menopausal for at least 2 years and follicle stimulating hormone greater than 40

Heart Failure Exclusion Criteria:

  • Patients with atrial fibrillation or heart failure believed to be secondary to atrial fibrillation
  • Morbidly obese patients with a body mass index greater than 35
  • Patients with uncontrolled hypertension, greater than 160/100
  • Anemia with a hemoglobin less than 9
  • Severe renal insufficiency (creatinine clearance less than 30 by the Cockcroft-Gault formula)
  • Patients with significant non-cardiac comorbidities
  • Orthopedic limitations that would prohibit them from performing the elbow-flexor exercise
  • Current smoker or smoking history of 15 packs or more per year
  • Women currently taking hormone replacement therapy

Healthy Control Inclusion Criteria:

  • Ages 20-75 years
  • Sedentary, no regular physical activity for at least 6 months prior
  • Post-menopausal for at least 2 years and follicle stimulating hormone greater than 40

Healthy Control Exclusion Criteria:

  • History of cardiovascular related abnormalities or pulmonary abnormalities
  • Morbidly obese patients with a body mass index greater than 35
  • Patients with uncontrolled hypertension, greater than 160/100
  • Anemia with a hemoglobin less than 9
  • Orthopedic limitations that would prohibit them from performing the elbow-flexor exercise
  • Current smoker or smoking history of 15 packs or more per year
  • Women currently taking hormone replacement therapy

Studieplan

Denne delen gir detaljer om studieplanen, inkludert hvordan studien er utformet og hva studien måler.

Hvordan er studiet utformet?

Designdetaljer

  • Primært formål: Grunnvitenskap
  • Tildeling: Ikke-randomisert
  • Intervensjonsmodell: Parallell tildeling
  • Masking: Ingen (Open Label)

Våpen og intervensjoner

Deltakergruppe / Arm
Intervensjon / Behandling
Annen: Heart Failure Patients
Patients with heart failure will undergo intervention of muscle contraction with metabolite solution administration. Maximal voluntary muscle contraction exercise with varying metabolite solution administration of adenosine triphosphate, lactate, and protons with phosphate buffer.
Legemiddel: Muscle Contraction with Metabolite Solution Administration
Participants will perform maximal elbow flexor or knee extensor contractions before and after administration of metabolite solutions of pH 7.2, pH 7.0 and pH 6.6
Andre navn:
  • adenosine triphosphate, lactate, and protons with phosphate buffer
Annen: Control Participants
Healthy control participants will undergo intervention of muscle contraction with metabolite solution administration. Maximal voluntary muscle contraction exercise with varying metabolite solution administration of adenosine triphosphate, lactate, and protons with phosphate buffer.
Legemiddel: Muscle Contraction with Metabolite Solution Administration
Participants will perform maximal elbow flexor or knee extensor contractions before and after administration of metabolite solutions of pH 7.2, pH 7.0 and pH 6.6
Andre navn:
  • adenosine triphosphate, lactate, and protons with phosphate buffer

Hva måler studien?

Primære resultatmål

Resultatmål
Tidsramme
Elbow Flexor Maximal Voluntary Contraction in newton-meters
Tidsramme: 2 minutes
2 minutes

Samarbeidspartnere og etterforskere

Det er her du vil finne personer og organisasjoner som er involvert i denne studien.

Sponsor

University of Utah

Etterforskere

  • Hovedetterforsker: Markus Amann, PhD, University of Utah

Studierekorddatoer

Disse datoene sporer fremdriften for innsending av studieposter og sammendragsresultater til ClinicalTrials.gov. Studieposter og rapporterte resultater gjennomgås av National Library of Medicine (NLM) for å sikre at de oppfyller spesifikke kvalitetskontrollstandarder før de legges ut på det offentlige nettstedet.

Studer hoveddatoer

Studiestart

1. september 2013

Primær fullføring (Faktiske)

3. januar 2018

Studiet fullført (Faktiske)

3. januar 2018

Datoer for studieregistrering

Først innsendt

29. juli 2013

Først innsendt som oppfylte QC-kriteriene

6. august 2013

Først lagt ut (Anslag)

9. august 2013

Oppdateringer av studieposter

Sist oppdatering lagt ut (Faktiske)

8. januar 2018

Siste oppdatering sendt inn som oppfylte QC-kriteriene

4. januar 2018

Sist bekreftet

1. januar 2018

Mer informasjon

Begreper knyttet til denne studien

Ytterligere relevante MeSH-vilkår

Andre studie-ID-numre

  • 62914

Denne informasjonen ble hentet direkte fra nettstedet clinicaltrials.gov uten noen endringer. Hvis du har noen forespørsler om å endre, fjerne eller oppdatere studiedetaljene dine, vennligst kontakt register@clinicaltrials.gov. Så snart en endring er implementert på clinicaltrials.gov, vil denne også bli oppdatert automatisk på nettstedet vårt. .

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