In relation with the published article "Natriuretic Peptide Concentrations and Echocardiography Findings in Patients with Micro-atrial Fibrillation", we have issued a comment. The authors of the article addressed a widely discussed topic of "Short episodes of fast arrhythmias initially detected in records on implantable devices". Further, these episodes are studied already by Holter monitoring of different durations with assessment of their clinical significance. This is the subject of the cited article and our comment.