[Age-related changes in the morphology and functional state of the heart]

The aim of this study was to assess age-related morpho-functional peculiarities of the heart on the basis of investigating the chrono-inotropic dependence of left ventricular [LV] myocardium. The results of this investigation are of importance for geriatric practice. They are necessary for determining the markers and elaborating the quantitative criteria of detecting the early stages of heart failure and finding the ways to its correction in elderly people. Twenty subjects aged 20-35 and forty four subjects aged 60-74 without clinical symptoms of cardiovascular pathology were investigated by means of stress-echocardiography. The indices of systolic and diastolic functions of the heart were studied by means of the transesophageal atrial electric pacing (TAEP) at baseline and at each frequency of pacing with the assessment of degree and type of LV myocardium hypertrophy. In all of the subjects investigated the results of TAEP were negative, i.e. they showed no signs of coronary insufficiency. In elderly people the increment values of contraction and relaxation velocity indices at the same pacing frequency were significantly lower (P < 0.05) in comparison with ones obtained in younger subjects. In elderly people a decrease of the maximal relaxation velocity occurred at submaximal age-related heart rate (on the average 135 beats/min) as compared to intermediate pacing frequencies whereas in younger subjects a further increment of this value continued. The LV hypertrophy developing with ageing plays on the one hand a compensatory role but on the other hand it deteriorates the diastolic function. The inefficiency of work of the old heart while pacing is an important factor limiting functional capabilities of the heart.