Reply to the comment by Al-Khafaji and Cho

Excerpt

Sir: We thank Drs. Al-Khafaji and Cho for their interest in our study and are grateful to have the opportunity to respond. Their comments raise an important issue: how can atrial fibrillation occurring in the ICU be compared with that in the general population? The incidence of atrial fibrillation is higher in ICU patients, and the risks factors are clearly different except as regards age [1, 2, 3]. The course of the arrhythmia also differs, and it is noteworthy that patients who have experienced atrial fibrillation in the ICU are discharged without arrhythmias and without anti-arrhythmic medications [3]. Clearly, atrial fibrillation in ICU could be viewed as the interaction between specific risks factors and an underlying cardiac susceptibility, but in ICU the cardiac component passes on a second rank. Consequently we must consider the point raised by Drs. Al-Khafaji and Cho in this way. Accordingly, it has been shown after noncardiac thoracic surgery that the left and right atrial sizes are in a normal range and do not differ between patients who develop or do not develop surpaventricular tachydysrhythmias [4]. Nevertheless, we agree with Drs. Al-Khafaji and Cho: further studies including echocardiography are necessary to definitively differentiate atrial fibrillation occurring in ICU from that in the general population. …