RESULTS OF STUDYING ISOSORBIDE MONOTITRATE PHARMACODYNAMICS IN PATIENTS WITH FUNCTIONAL CLASS 1 AND 2 STABLE ANGINA BY HEART RATE VARIABILITY ANALYSIS
Aim. To study the effect of isosorbide monotitrate (ISMN) on heart rate variability (HRV) in patients with functional class 1 and 2 (FC) stable angina (SA). Materials and methods. Eighty five male patients with FC 1 and 2 SA at the age of 53,1±5,56 years old were examined. The control group included 42 healthy men. All the examined subjects underwent rhythmocardiographic investigation ( RCI ). HRV in 1 and 2 FC SA was assessed before and 1 hour after taking ISMN in the dose of 20 mg. Results. In the group of 1 and 2 FC SA patients, there was observed dysregulation of sinoatrial node manifested by 2,5 fold decrease in total HRV at the expense of fall in humoral-metaboic amplitude ( l ) on average by 1,5 times, sympathetic ( m ) – 2,5 times, parasympathetic ( s ) – 3–4,5 times, shift of vegetative regulation to the side of humoral-metabolic one with decreased parasympathetic one, reduced manifestation of reaction to stimulus. After taking ISM, total HRV increase at the expense of growth of σl, σm amplitude with decreased σs, shift of vegetative regulation pattern to the side of humoral-metabolic effect, sympathetic effect with reduced protective parasympathetic peripheral regulation link was registered. At the same time, under ISMN effect, reaction to stimulus in Valsalva test significantly increased from 17,056±8,609 to 25,411±12,681%, in active orthostatic test – from –20,733±9,508 to –23,522 9,886%, in stress – ( PWC <sub>120</sub>) rehabilitation time after stimulus effect decreased from 45,177±10,732 to 42,198±6,251 that is beneficial from positions of HRV. Conclusion. Thus, taking into account peripheric vegetative dysregulations arising with ISMN, it is rational to use RCG-investigation for choosing and monitoring the conducted therapy with organic nitrates, in particular ISMN.