The importance of highly effective lipid-lowering therapy with atorvastatin in the normalization of the autonomic regulation of heart rate in patients with STEMI
Authors: Barmenkova Y , Dushina E , Burko N , Oleinikov V 
Published: November 2020

Abstract

Purpose
To assess the importance of highly effective lipid-lowering therapy with atorvastatin in the normalization of the autonomic regulation of cardiac activity in patients with myocardial infarction with ST segment elevation (STEMI).

Methods
The study included 130 patients with STEMI aged 51.3±8.9 years, the majority of males (91%). Inclusion criteria: age from 35 to 70 years, STEMI confirmed by ECG and the level of biomarkers (troponin I, CK-MB), the presence of hemodynamically significant stenosis of a culprit artery according to coronary angiography provided that other coronary arteries are occluded no more than 50%, left main coronary artery - not more than 30%. Exclusion criteria: a history of myocardial infarction, CHF III-IV NYHA, bundle branch block, atrial fibrillation, artificial pacemaker. All patients took atorvastatin at a dose of 40–80 mg/day for 48 weeks after STEMI. As part of a further study at the 7th-9th day and 48 weeks after STEMI, 24-hour ECG monitoring was performed with the Astrocard system. The spectral parameters of heart rate variability (HRV) were evaluated: TotP (ms2), ULF (ms2), VLF (ms2), LF (ms2), HF (ms2), LF / HF. By the 48th week of treatment, patients were divided into groups depending on the achievement of the target level of low density lipoproteins (LDL) of less than 1.4 mmol / l or less than 50% of the initial values: 64 people who reached target values of LDL and formed the group of high-effective lipid-lowering therapy “H”, the group of low effective treatment “L” included 66 patients whose LDL did not meet the recommended level. The groups were matched by gender, age, and anthropometric data.

Results
In the “H” group, by the 48th week, a pronounced power amplification of all spectral components was obtained. The TotP parameter increased from 13021 (95% CI 10967; 15076) ms2 to 20988 (95% CI 17617; 24358) ms2 (p=0.0001); HF - from 164 (95% CI 105; 222) ms2 to 249 (95% CI 178; 321) ms2 (p=0.003). An increase in the low-frequency components of HRV was observed: an increase in ULF from 10695 (95% CI 8985; 12406) ms2 to 20401 (95% CI 15099; 25703) ms2 (p=0.0001), VLF - from 1473 (95% CI 1212; 1734) ms2 to 1734 (95% CI 1478; 1990) ms2 (p=0.01), LF - from 761 (95% CI 573; 949) ms2 to 909 (95% CI 736; 1082) ms2 (p=0.02). Against the background of an increase in all parameters of the frequency spectrum, the sympathovagal balance coefficient LF / HF decreased from 6.6 (95% CI 5.7; 7.6) to 5.2 (95% CI 4.3; 6.1) ( p=0.004). An analysis of the HRV indicators dynamics in the L group revealed an increase in only the total spectrum power - TotP from 12740 (95% CI 10947; 14533) ms2 to 20195 (95% CI 16619; 23770) ms2.

Conclusions
Highly effective therapy with atorvastatin in STEMI patients helps to normalize the parameters of the autonomic regulation of heart rate in the post-infarction period due to the increased effects of parasympathetic activity.

Funding Acknowledgement
Type of funding source: None