ischaemic preconditioning of the human heart. - Leicester Research ...

6.4 DISCt'SSION'
'rhe present studý is the first to report that ischaernic injury of the human myocardium
is not exacerbated bN increased age and that ischaernic preconditioning equally
protects the myocardium of all ages These findings have important clinical
implications regarding the selection and treatment of patients presenting with
ischaernic syndromes and thev warrant
further discussion.
Ischaernia occurs in a number of clinical settings that include myor-ardial infarction,
coronary angioplasty and cardiac surgery Ischaernic heart syndromes are the
commonest cause of death in the elderly [ 123,1811 and it has been suggested that a
greater vulnerability to ischaemic injury of this age group is a major contfibutor
[ 123,181,3311 This thesis finds support In experimental studies showing that a greater
calcium overload 1121 and increased oxygen free radical generation [641 occur in the
senescent rat heart and that hearts become less tolerant to ischaernia with age [3001. In
contrast, mv results have clearly demonstrated that in the human myocardium the
degree of ischaemic injur-y is unrelated to age. The controversy is further fuelled by
the results recently reported by Mariam et a] [2021 showing that the aged human atnal
myocardium, also obtained from patients undergoing cardiac surgery, has a reduced
capacity to recover developed force after hypoxia or simulated ischaemia than
younger myocardium although contraction duration, time to peak tension and time to
50% relaxation were unaffected by age Therefore, the results of the study
by Mariani
et al [2021 mav be subject to different interpretations depending on the parameter
examined
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