An elderly man with acute anterior wall myocardial infarction who underwent medical therapy followed by angioplasty and stenting was referred to our centre for evaluation of sleep-disordered breathing. The gentleman had moderate hypothyroidism for which he was on replacement therapy. At our centre PSG showed OSA for which a trial of CPAP was given. On correction of OSA by CPAP, presence of underlying CSA was unmasked. The patient improved over time on intensified medical therapy, continuous use of CPAP and regulated thyroid replacement therapy.