Nortamo S, et al. - This study is performed to assess the value of heart rate variability (HRV), a marker of cardiac autonomic regulation, in predicting new-onset atrial fibrillation (AF) in coronary artery disease (CAD). The outcome suggests that the impaired cardiac autonomic regulation measured by detrended fluctuation analysis (DFA1) and low-frequency and high-frequency components of the power spectrum (LF/HF ratio) ratio predict the development of new-onset AF and also or even better than LA diameter in patients with CAD.