[Time series analysis of the surface electrocardiogram in patients with atrial fibrillation]

Atrial Fibrillation is one of the most common arrhythmias. Most statistical analyses had been performed on intra atrial electrocardiograms while, diagnosis of this disorder is made more commonly by use of surface electrocardiogram. The aim of this study was to investigate the abnormality of the electrical system of the heart by using the 12- lead ECG. The 12-lead ECGs of 5 patients with atrial fibrillation and that of a healthy subject were studied for 2.5 minutes and compared with each other. Our study showed that in both normal and abnormal hearts, [V1, V2, V3], [V4, V5, V6], [I, II, III] and [aVR, aVF, aVL] were correlated. The correlation between I, II, III leads had no relation to AF; whereas correlation between aVR, aVF and aVL decreased in the patients. This study showed that we can consider both focus and reentrant theories acceptable for explanation of electrical behavior of heart in AF patients

Factors related to surgery worries among Iranian high school adolescents

Surgery operations are the fearful events among all other medical procedures. This fear causes anxiety and stress which affects the outcome of treatments, recovery from surgery and some maladaptive behaviors. To cope with surgery worries and minimize the fear, it is important to study these fears and its associated factors. This study attempts to explore the surgery worries and the associated factors among Iranian high school adolescents. To measure surgery worries, high school adolescents of age 11-15 completed the Child Worries Questionnaire [CPCI] adolescent form, and also answered the questions about the 14 independent variables [sex, age, parents education and occupation, previous hospitalization experience of child and immediate family and friends, number of hospitalization during Child's life long, previous surgery experience of child and her or his immediate families, death of close friends in hospital]. Multivariate regression method was used for statistical analysis to determine the effective factors. The results of this study showed that the Iranian Adolescents have most worries about the "Not being able to do the same things as before" and least worries about "What I will feel during the anesthesia". The factors associated with Surgery worries are; parent's education [P = .021 for father and 0.049 for mother], adolescent previous experience and number of hospitalizations [P = 0.025 and P = 0.008, respectively], the number of previous hospitalizations [P = .003], previous experience of hospitalization of immediate family and friends [P = 0.035]. The findings of this study have implications for parents, family, hospitals' staff and care given. It seems, according to the findings of this study, there should be a special educational program for children who are going to be operated in a hospital ward to reduce their worriships