Inclusion Criteria:  Age> 18 years; Confirmed infection with SARS-CoV-2; Patients with a first clinical episode of AF ≥30 s at admission or during hospitalization for COVID-19;  Patients with:  implantation of an ILR, a PMK, or an ICD during COVID-19 hospitalization or within 30 days after hospital discharge, or an ILR, a PMK, or an ICD implanted before COVID-19 hospitalization.  Exclusion Criteria:  History of AF or flutter irrespective of type; Moderate/severe mitral stenosis; Mechanical prosthetic heart valve(s); Kidney failure treated with permanent dialysis; Any condition (e.g. psychiatric illness, dementia) or situation, that in the investigators opinion could put the subject at significant risk, confound the study results, or interfere significantly with the subject participation in the study; Unwillingness to participate.