This is a prospective observational pilot study. Fifteen mild to severe OSA patients and five age- and Body Mass Index (BMI)-matched controls will undergo a DE-MRI. Demographics, medical history and polysomnography results will be collected. Patients diagnosed with obstructive sleep apnea have undergone a polysomnography before the study and were diagnosed based on this test. The investigators will not be performing a polysomnography for any of the patients, just collecting the previous results from their medical charts to confirm they have a true OSA diagnosis for their inclusion in the study.~Patients will be followed over a period of 6 months with a wearable device (WATCHPAT 300) that will record a home sleep apnea study biweekly, including OSA metrics like AHI and nocturnal oxygen variations. Patients will also use an ElectroCardioGram (ECG) Check device for arrhythmia detection.
The investigators hypothesize that Obstructive Sleep Apnea (OSA) is an independent risk factor for atrial fibrosis development. The investigators aim to prove the presence and progression of atrial fibrosis on Delayed Enhancement Magnetic Resonance Imaging (DE-MRI) in OSA patients without atrial fibrillation (AF).~The investigators will also investigate the correlation between OSA metrics (nocturnal oxygen saturation and Apnea Hypopnea Index (AHI)) and degree of fibrosis at baseline and its progression.