Impact Of Closure Of Patent Foramen Ovale On Apnoea-Hypopnoea-Index, Nocturnal Hypoxemia And Systemic Vascular Function In Patients With Obstructive Sleep Apnoea

Inclusion Criteria: * Patients with newly diagnosed moderate to severe OSA * Age \> 17 years * Written informed consent for study participation. Exclusion Criteria: * Patients with other pulmonary disease associated with oxygen desaturation (other than obesity-associated pulmonary restriction) * Patients with central sleep apnea syndrome * Patients with other causes of pulmonary hypertension * Intracardiac shunt other than via PFO * Severe valvular heart disease * Abnormal left ventricular (LV) systolic function (ejection fraction \<50%) * Obesity with BMI \> 40 * Contraindication to TOE * Severe pulmonary arterial hypertension (mean pulmonary artery pressure \> 45 mmHg)