[Assessment of dynamics of the autonomic cardiovascular system regulation based on low-frequency rhythm synchronization in patients with ischemic heart diseases complicated by myocardial infarction treated with metoprolol].

AIM

To develop a procedure for assessing the adequacy of metoprolol use in patients with coronary heart disease (CHD) on the basis of synchronization of 0.1-Hz rhythms in cardiac rhythm variability (CRV) and vascular blood filling in the microcirculatory bed (MCB). Materials and methods. 43 patients with CHD (age 63 +/- 8 years), who had sustained myocardial infarction about 6 months before, were examined. Synchronous registration of ECG and a pulsogram were made during an orthostatic test before and after therapy with metoprolol in the maximum tolerable doses during 3 months. The presence of synchronization of 0.1-Hz rhythms identified from a series of R-R intervals and the pulsogram was determined from the difference of phases; the total percent of synchronization (S) was estimated.

RESULTS

The authors identified 2 groups of CHD patients: those with positive (n=21) and negative (n=16) orthostatic S, trends during treatment. The groups were matched by major clinical characteristics. There was an inverse relationship between the values of S, in the lying and standing position prior to or following treatment. It is suggested that there is the optimum range of 0.1-Hz rhythm synchronization values in the cardiovascular system during beta-blocker therapy in patients with CHD.

CONCLUSION

There is a possibility applying an objective approach to assessing the adequacy of metoprolol treatment in CHD patients on the basis of synchronization of 0.1-Hz fluctuations in variations CR V and vascular blood filling in MCB.