rss
Heart 2000;83:161-166 doi:10.1136/heart.83.2.161
  • Cardiovascular medicine

Dissociation between muscle metabolism and oxygen kinetics during recovery from exercise in patients with chronic heart failure

  1. A Hanadaa,
  2. K Okitaa,
  3. K Yonezawaa,
  4. M Ohtsuboa,
  5. T Kohyaa,
  6. T Murakamia,
  7. H Nishijimab,
  8. M Tamurac,
  9. A Kitabatakea
  1. aDepartment of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita–15, Nishi–7, Kitaku, Sapporo 060–8638, Japan, bSapporo Health Promotion Centre, Sapporo, Japan, cBiophysics Group, Research Institute for Electronic Science, Hokkaido University, Sapporo, Japan
  1. Dr Hanada email:cvext{at}med.hokudai.ac.jp
  • Accepted 17 August 1999

Abstract

OBJECTIVE To estimate muscle metabolism and oxygen delivery to skeletal muscle in patients with chronic heart failure.

METHODS 13 patients with chronic heart failure and 15 controls performed calf plantar flexion for six minutes at a constant workload of 50% of one repetition maximum. During recovery from exercise, skeletal muscle content of oxygenated haemoglobin (oxy-Hb) and the level of phosphocreatine (PCr) were measured by near-infrared spectroscopy and 31P-magnetic resonance spectroscopy, respectively.

RESULTS The mean (SD) time constants of PCr and oxy-Hb during recovery from exercise were significantly greater in patients with chronic heart failure than in normal subjects (τ PCr: 76.3 (30.2) s v 36.5 (5.8) s; τ oxy-Hb: 48.3 (7.3) s v 30.1 (7.7) s; p < 0.01). Both time constants were similar in normal subjects, while the τ PCr was significantly greater than the τ oxy-Hb in patients with chronic heart failure.

CONCLUSIONS The slower recovery of PCr compared with oxy-Hb in patients with chronic heart failure indicates that haemoglobin resaturation is not a major rate limiting factor of PCr resynthesis. It is suggested that muscle metabolic recovery may depend more on oxygen utilisation than on haemoglobin resaturation or oxygen delivery in patients with chronic heart failure.

Footnotes

    This Article

    1. Abstract
    2. Full text
    3. PDF

    Responses

    1. Submit a response
    2. No responses published

    Latest from Education in Heart

    Latest from Education in Heart

    Register for free content

    The full back archive is now available for all BMJ Journals. Institutional subscribers may access the entire archive as part of their subscription. Personal subscribers will also have access to all content when logged in. Non-subscribers who register have free access to all articles published before 2006 right back to volume 1 issue 1. Register here to access the free archive of all BMJ Journals.

    Don't forget to sign up for content alerts so you keep up to date with all the articles as they are published.