[1] Aalborg Univ Hosp, Dept Otolaryngol Head & Neck Surg & Audiol, Hobrovej 18-22, DK-9000 Aalborg, Denmark
[2] Aarhus Univ Hosp, Dept Otolaryngol Head & Neck Surg & Audiol, Aarhus, Denmark
[3] Harvard Med Sch, Brigham & Womens Hosp, Dept Med, Div Cardiovasc Med, Boston, MA USA
[4] Liverpool John Moores Univ, Univ Liverpool, Liverpool Ctr Cardiovasc Sci, Liverpool, England
[5] Liverpool Heart & Chest Hosp, Liverpool, England
[6] Aalborg Univ, Danish Ctr Hlth Serv Res, Dept Clin Med, Aalborg, Denmark
[7] Aalborg Univ Hosp, Dept Cardiol, Aalborg, Denmark