Oxygen extraction rate of the myocardium at rest and on exercise in various conditions.

نویسندگان

  • K Binak
  • N Harmanci
  • N Sirmaci
  • N Ataman
  • H Ogan
چکیده

The ability to study the oxygen arterio-venous difference in the heart and to measure coronary blood flow has led to a unique concept of the way in which oxygen demands of the heart are met. The coronary sinus oxygen content is low and apparently constant in health and in a wide variety of diseases (anemia, arterio-venous fistula, hyperthyroidism), and oxygen demand is met by increased blood flow, not increased extraction (Bing et al., 1949; Bing, 1951; Wegria et al., 1958; Leight et al., 1956). Only conditions in which coronary flow is restricted behave differently (Messer et al., 1962). This is in marked contrast to the behaviour of skeletal muscle during exercise (Donald, 1959). The unique nature of the myocardial response to exertion and the relatively few data on which these conclusions are based indicate the need for further study (Messer et al., 1962; Lombardo et al., 1953; Regan et al., 1961). The present study attempts to answer two questions. (1) Is coronary venous oxygen content and oxygen extraction of the myocardium constant at rest in normal subjects and in patients with various diseases ? (2) Does the heart meet increased oxygen demand solely by increased coronary blood flow?

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عنوان ژورنال:
  • British heart journal

دوره 29 3  شماره 

صفحات  -

تاریخ انتشار 1967