Atrial Fibrosis in Obstructive Sleep Apnea Patients: A Pilot Study

Inclusion Criteria: Group A: 10 patients 18-75-year-old With mild OSA (5\<AHI\<15), confirmed by polysomnography. No previous AF diagnosis on the medical chart Group B: 10 patients 18-75-year-old With moderate OSA (15\<AHI\<30), confirmed by polysomnography. No previous AF diagnosis on the medical chart Group C: 10 patients 18-75-year-old With severe OSA (AHI\>30), confirmed by polysomnography. No previous AF diagnosis on the medical chart Group D (mild OSA+ AF): 10 patients 18-75-year-old With mild OSA (5\<AHI\<15), confirmed by polysomnography. Previous AF diagnosis * In this group, patients with AF and OSA who already have done MRI might be included. Group E (severe OSA +AF): 10 patients 18-75-year-old With severe OSA (AHI\>30), confirmed by polysomnography. Previous AF diagnosis \*In this group, patients with AF and OSA who already have done MRI might be included. Group F (Control): 10 Patients 18-75-year-old No previous OSA and/or AF Diagnosis on the medical chart Exclusion Criteria: * History of chronic heart failure (LVEF \< 50%), AF, myocardial infarction, valvular disease. * Prior cardiac or chest surgery. * Other advanced pulmonary disease (severe Chronic Obstructive Pulmonary Disease (COPD) or asthma, pulmonary hypertension) or central sleep apnea. * Contraindications to DE-MRI (e.g. allergy to gadolinium, pacemakers, defibrillators (ICD's), other devices/implants contraindicated for MRI, glomerular filtration rate \<30 ml/min, etc.). * Pregnancy. * Inability to give informed consent.