[Estimation of immune response parameters in patients with frequent premature ventricular contractions without signs of organic pathology of the cardiovascular system].

AIM: To study the specific features of an immune response and the role of infectious pathogens in the occurrence, development, and maintenance of ventricular ectopic activity in patients without signs of organic disease of the cardiovascular system (CVS). SUBJECTS AND METHODS: The investigation enrolled 91 patients (27 men and 64 women with a mean age of 36.5 +/- 11.5 years) with premature ventricular contractions (PVC) without signs of organic CVS pathology. A control group comprised 31 healthy volunteers. In addition to standard physical examination, a study of N-terminal pro-brain natriuretic peptide (NT-proBNP) and cellular and humoral immune parameters was performed and the serological and molecular genetic markers of infections were determined in all the patients. RESULTS: The persons with PVC, as compared to the control group, were recorded to have a higher NT-proBNP level (49.2 pg/ml versus 25.4 pg/ml; p = 0.001) accompanied by an increase in both the total number of PVC and the number of coupled PVC and the episodes of ventricular tachycardia. They were also found to have elevated CD3(+)HLA-DR+ (2.4% versus 1.56%) and CD3(+)CD95+ (27.6% versus 18.8%) counts (p = 0.001). In patients with a C-reactive protein level of more than 2 mg/l, the total number of PVC was larger than that in the other patients (p = 0.065). The patients with PVC did not show a statistically significant difference from the controls in the levels of antiviral and antibacterial antibodies. The people with PVC displayed a number of relationships between the infectious pathogen antibody titers and the ECG Holter monitoring and echocardiography readings. CONCLUSION: In the patients with PVC without signs of organic CVS pathology, the parameters of an immune response were not different from those obtained in the control group, which was likely to be associated with the involvement of the immune system in the development and maintenance of ventricular arrhythmias.

The role of Interleukin-6, its -174 G>C polymorphism and C-reactive protein in idiopathic cardiac arrhythmias in children.

UNLABELLED: ABSTRACT Purpose: Knowledge about the role of inflammation in the pathogenesis of arrhythmias in children is limited. Several studies have suggested a relationship between plasma IL-6 levels and/or the -174G>C IL-6 gene polymorphism and atrial fibrillation in adults. Our present study was performed to investigate whether serum IL-6, -174G>C IL-6 polymorphism and C-reactive protein (CRP) are associated with arrhythmias of unknown origin in children. METHODS: The study included 126 children diagnosed with supraventricular or ventricular arrhythmia. Patients with congenital heart defects as well as arrhythmias of known origin were excluded from the study. The control group comprised 37 healthy children. The 24 hour Holter electrocardiography monitoring was performed. Serum IL-6, -174 GC IL-6 polymorphism and CRP concentrations were measured on admission. RESULTS: There were no differences in IL-6, CRP and -174 G>C IL-6 genotype distribution between the control and patient groups. No significant differences in IL-6, CRP and -174 G>C IL-6 genotypes were observed between children with supraventricular or ventricular arrhythmias. The severity of arrhythmias showed also no associations with IL-6, CRP or -174 G>C IL-6 genotypes. CONCLUSION: The results suggest that idiopathic cardiac arrhythmias of unknown origin in children are not associated with selected pro-inflammatory markers of infections i.e. elevated IL-6, CRP or -174 G>C IL-6 polymorphism. This new information can effectively reduce the total financial cost of unnecessary diagnosis and treatment of children affected by cardiac arrhythmias.

Mast cell degranulation--a mechanism for the anti-arrhythmic effect of endothelin-1?

BACKGROUND AND PURPOSE: The aim of this study was to investigate whether the previously reported anti-arrhythmic effect of endothelin-1 (ET-1) is mediated by degranulation of cardiac mast cells prior to myocardial ischaemia. EXPERIMENTAL APPROACH: Male Sprague-Dawley rats received either ET-1 (1.6 nmolxkg(-1)) in the presence or absence of disodium cromoglycate (DSCG; 20 mgxkg(-1)xh(-1)) prior to coronary artery occlusion (CAO). In separate experiments rats were given compound 48/80 (50 microgxkg(-1)) to compare the effects of ET-1 with those of a known mast cell degranulator. Ischaemia-induced ventricular arrhythmias were detected through continuous monitoring of a lead I electrocardiogram. After 30 min of CAO, the hearts were removed and mast cell degranulation determined by histological analysis. A parallel series of sham groups were performed to determine the direct effects of ET-1 and compound 48/80 on mast cell degranulation in the absence of ischaemia. KEY RESULTS: ET-1 and compound 48/80 both exerted profound anti-arrhythmic effects, significantly reducing the total number of ventricular ectopic beats (P < 0.001) and the incidence of ventricular fibrillation (P < 0.05). These anti-arrhythmic effects were abolished by concomitant DSCG infusion prior to CAO. In sham animals ET-1 and compound 48/80 both induced mast cell degranulation (P < 0.001), an effect which was abolished by DSCG, confirming their ability to induce degranulation of mast cells. CONCLUSIONS AND IMPLICATIONS: These results demonstrate for the first time that when given prior to ischaemia ET-1 mediates its anti-arrhythmic effects, at least in part, via cardiac mast cell degranulation.