Metabolic and Ventilatory Responses to Exercise in Patients with a Deficient O2 Utilization by a Mitochondrial Myopathy
Patients with an abnormal mitochondrial metabolism may become easily fatigued. In some of them severe exercise intolerance 1,2,6 is present. A lactic acidosis, occurring on low exercise levels then causes a specific response of ventilatory and metabolic variables when considered as a function of the oxygen consumption (V̇O2) as a measure for the metabolic demand 1,4. In this report exercise responses of three young patients with a mitochondrial myopathy are described. The exercise tests were repeated at regular time intervals. The responses during these tests were analyzed in relation to basic mechanisms in order to determine the effects of therapy.
KeywordsBase Excess Respiratory Quotient Anaerobic Threshold Mitochondrial Myopathy Exercise Response
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