Authors: Batushkin V. V.1, Ashdari M. Ch.2
1Kyiv Medical University, Kyiv, Ukraine
2Kyiv City Clinical Hospital No. 5, Kyiv, Ukraine
Prevention of Heart Failure and Improvement of Prognosis in Patients after Primary Transcutaneous Angioplasty by Adding L-carnitine at the Acute Stage of Myocardial Infarction
Abstract
Due to the active tactics of timely delivery of infarction patients for revascularization in recent years, the proportion of patients with the most severe form of myocardial infarction (MI), Q-infarction, in our clinic decreased by 15.7%. There was a significant decrease in oneyear mortality due to acute myocardial infarction (AMI) from 4.2% in 2016 to 2.53% in 2018.
The objective of our work was to evaluate the hospital course and to prevent post-infarction heart failure (HF) during the first 6 months from the date of AMI in patients after primary transcutaneous angioplasty under the influence of cardiocytoprotective therapy with L-carnitine.
We examined and treated 97 patients with AMI aged 52–76 years (mean age 66.3 ± 7.2 years) who were hospitalized on the first day of the disease. All patients were randomly assigned to one of two groups. The first group consisted of 47 patients who received L-carnitine i.v. 3.0 g in the first 3 hours of hospitalization on day 1 of the disease and 2.0 g on days 2–10 of treatment. The control group included the results of a survey of 50 patients whose mean age was 64.6 years and who received conventional therapy from the first day after stenting (group II), according to the National Recommendations for the Treatment of Patients with ST-Elevation AMI (2018).
Cardiocytoprotective therapy with L-carnitine statistically significantly prevented the development of HF after AMI and significantly improved prognosis in patients after primary transcutaneous angioplasty, reduced the relative risk of developing life-threatening arrhythmias during the 6-month observation regardless of localization of the affected area.
Early initiation of L-carnitine at the acute stage of MI contributed to an earlier (day 10 of observation) and complete (within 1 month) restoration of autonomic nervous system function. Specifically, in patients receiving carnitine, the standard deviation normal to normal (SDNN) on the day 10 of the treatment increased by 67.6%, the root mean squared successive differences (RMSSD) increased by 33.4%, while in the control group these barely reached the normal limits. In the course of metabolic therapy, the proportion of differences in successive RR intervals greater than 50 ms (PNN50) showed more than 4-fold increase. In the control group, the changes in the above indicators were less significant, and the PNN50 even decreased beyond the normal limit. The level of entropy on the day 10 of treatment with L-carnitine significantly decreased by 65.4% (p < 0.05), which indicated stabilization of the processes of myocardial adaptation.
Among other systemic indicators of homeostasis regulation, in our opinion, an interesting observation was significant increase in the overall level of bioenergy under the influence of improvement of the state of reserves of vascular regulation and operative control of vegetovascular regulation.
The course appointment of carnitine significantly improved the HF functional class by NYHA according to the results of the 6-minute walk test after 1 month of follow-up. Thus, with posterior infarction, the number of patients with NYHA class I-II HF increased by 45.5%, from 37.5 to 68.8%, and only by 19.8% in the control group (p <0.05). Accordingly, the number of patients with NYHA class III–IV HF decreased almost twice in the L-carnitine group (p = 0.033). In the anterior localization of myocardial infarction, the group of patients with NYHA class I–II HF who received metabolic therapy after 1 month increased by 2.12 times (from 34.7 to 73.7%) (p = 0.02), whereas in control group it increased only by 46.2% (p = 0.7). At the same time, the number of patients with NYHA class III–IV HF in the L-carnitine group decreased almost 2.5-fold, from 65.3 to 26.3%, and from 68.2 to 40.8% in the control group.
Administration of L-carnitine in the acute period prevented the progression of pathological remodeling of the left ventricle: the number of patients with critical increase in the endsystolic index and end-diastolic index was 2.8 times lower (p = 0.015). At the same time, there was significant improvement in the heart pump function, and complete recovery of global contractility (left ventricular ejection fraction > 50%) was observed in 25.5% of patients within 1 month after MI.
Under the influence of metabolic therapy, the increase of NT-proBNP by the day 10 of observation was 35.7% less, which showed significantly lower volume of necrotized myocardium. Faster decrease in the level of NT-proBNP to subnormal values at the day 30 after treatment in the L-carnitine group suggested more favorable course after left ventricular remodeling.
Keywords: acute myocardial infarction after primary transcutaneous angioplasty, L-carnitine, heart failure, prognosis.