Cardiac repolarization abnormalities in children with familial Mediterranean fever

BACKGROUND: Familial Mediterranean fever (FMF) is an autoinflammatory disease that can have conduction disturbances and cardiac rhythm disorders as manifestations of cardiac involvement. The aim of the study is to assess the susceptibility of children with FMF to cardiac repolarization abnormalities and therefore arrhythmia in children with FMF. METHODS: A cross sectional study conducted on 60 children had FMF and 40 age and sex matched healthy controls. Cardiac repolarization markers, cardiac dimensions and functions were assessed by electrocardiogram (ECG) and conventional echocardiography in patients and controls. RESULTS: The mean ± SD age of the patients was 10.43 ± 3.472 years, corrected QT (QTc) and the ratio of peak to end T wave (Tpe) over QTc interval (Tpe /QTc) increased significantly in FMF patients more than healthy control (p value 0.023 and 0.022 respectively). P wave dispersion (Pd) was significantly higher in FMF patients with amyloidosis (p value 0.030). No significant difference was found in cardiac dimensions and functions between the two groups. We found a statistically negative correlation between Pd and age of patients at time of study, age of disease onset and age at diagnosis. On the other hand, we found a statistically significant positive correlation between Pd with number of attacks per year and disease severity score. Furthermore, Tpe/QTc ratio correlated with FMF 50 score, QTc correlated with 24 hours proteinuria. QT, JT intervals correlated with fibrinogen. CONCLUSIONS: FMF Patients may have increased risk of arrhythmia and should be monitored on regular basis. Compliance to colchicine therapy and better disease control might play a role in decreasing this risk.