Olga Senatorova
Tyumen State Medical University, Russia
Title: Sinus bradycardia in children: Biochemical parameters depending on clinical variant, possible criteria of differential diagnostics
Biography
Biography: Olga Senatorova
Abstract
Background: Destabilization of cardiac myocyte cell membrane, its structure and function influences on the development of sinus bradycardia (SB).
Purpose: To study total cholesterol (TC) of platelet membrane as cardiac myocyte model, total intracellular calcium (Ca2+) in platelets in children with SB without organic heart disease depending on the clinical variant and with autonomic dystonia syndrome (ADS) and idiopathic (asymptomatic) syndrome.
Methods: Children aged 3-13 years matched by sex and age were divided into three groups: group 1 consisted of healthy children (control group, n=30), group 2 consisted of children with idiopathic SB (n=20) and group 3 consisted of children with SB and ADS. Diagnostic tests and procedures were carried out. Special methods included TC and Ca2+ in platelets.
Results: TC volume in platelets of children in group 2 was significantly higher than TC volume in healthy children for 1.8 times, in group 3 – for 2.3 times (p<0.05). Besides, parameters of group 3 were definitely higher than values of group 2 (0.34±0.23 vs 0.27±0.15 mcM/ml, respectively, p <0.05). Decrease of Ca2+ in children with SB was revealed. The value of Ca2+ in children of group 2 showed significant lowering (0.05±0.009 mcM/ml, p<0.05) in comparison with healthy children (0.09±0.009 mcM/ml, p<0.05).
Conclusion: Elevated cholesterol level in the platelet membrane can be estimated as membrane destabilizing factor, altering electrochemical potential of the cell, lowering fluidity of the platelet cell membranes; it may serve as differential and diagnostic criteria of idiopathic SB with ADS. As calcium is the key regulator of several important cell functions, change of Ca2+ concentration in the citosol leads to misbalance of the intracellular processes; it may serve as the marker of idiopathic SB.