RESUMEN
Cardiac involvement as pericarditis, myocarditis and valvular disease is common in juvenile idiopathic arthritis [JIA]. However, there are few studies concerning systolic and diastolic functions of the left ventricle in children with JIA. P wave dispersion is a sign for the prediction of atrial fibrillation. A recent study found that rheumatoid arthritis patients had an abnormally high P wave duration and P wave dispersion, markers for supraventricular arrhythmogenicity. In this study, we aimed to evaluate P wave dispersion and its relation with diastolic dysfunction of the left ventricle in patients with JIA. We performed electrocardiography and Doppler echocardiography on patients and controls. Maximum and minimum P wave duration were obtained from electrocardiographic measurements. P wave dispersion defined as the difference between maximum and minimum P wave duration was also calculated. No statistically significant differences were found between the patients and controls in minimum, maximum P wave duration and P wave dispersion. Among the diastolic parameters in patients group, increased late flow velocity, decreased early flow velocity and prolonged isovolumic relaxation time reflected diastolic dysfunction. During 12 months of follow-up, no supraventricular arrhythmias were documented in JIA with diastolic dysfunction. JIA with diastolic dysfunction has normal atrial conduction parameters and therefore seemingly do not have an increased risk of atrial fibrillation