Development of left ventricular diastolic dysfunction in children who are in long-term remission of acute lymphoblastic leukemia

Abstract

Aim. To determine the frequency and nature of myocardial damage in children on the background of long-term remission of acute lymphoblastic leukemia, to assess the significance of the concentration of the N-terminal precursor of the brain natriuretic peptide and of the protein that binds fatty acids in blood serum. Methods. The observation group included 22 children aged 7 to 17 years, who are in long-term remission of acute lymphoblastic leukemia. The average duration of the remission was 6.1±1.0 years. All children were treated according to the standard and intermediate risk group protocol ALL-MB-2002. The control group included 65 children. A clinical and instrumental examination, including 12-lead electrocardiography, as well as complex transthoracic Doppler echocardiography was conducted. Analysis of the diastolic function of the myocardium was performed during assessment of the ratio of peak transmitral flow velocities (E/A), of the index of myocardial stiffness and of the time indicator B(E-Ea). The content of the N-terminal precursor of the brain natriuretic peptide and of the protein that binds fatty acids in blood serum was determined by enzyme immunoassay. Results. In 70% of the children with acute lymphoblastic leukemia who are in the remission stage for over 5 years, noted was the development of early signs of diastolic myocardial dysfunction, in 50% of the patients of this group reported was a significant increase in the concentration of the marker of heart failure - brain natriuretic peptide. At the same time, in a third of the examined individuals an increase in concentration of the protein that binds fatty acids was revealed, which may be indicative of myocardial damage at the cellular level. Positive correlation links between the indicators of initial manifestations of the evolving left ventricular diastolic dysfunction in children, who are in long-term remission of acute lymphoblastic leukemia, and the content of the N-terminal precursor of the brain natriuretic peptide have been revealed. Conclusion. The increase in the levels of the mentioned indicators makes it possible to identify high-risk groups for cardiovascular disease development among the cohort of children who are in long-term remission of acute lymphoblastic leukemia in order to develop preventive and rehabilitative programs.