Aims : The hypoventilation syndromes represent a variety of disorders that affect central ventilatory control, respiratory mechanics, or both. Obesity hypoventilation syndrome is a clinically important disorder with serious cardiovascular and metabolic consequences, increased morbidity and mortality, if unrecognized. CSA represents also a variety of disorders and/or results from various diseases, have a negative impact on patient prognosis depending also in the severity of underlying disease. HF patients with CSA are highly heterogeneous group with clinical relevant subgroups which has different prognosis and treatment response. This course aim to summarize the current knowledge regarding the: 1. early recognition and effective hypoventilation treatment using various currently available treatment modalities with the scope to improve patient-centered outcomes. 2. different clinical phenotypes of CSA in Heart failure (HF) patients , their correlation with prognosis and their relevance for identifying individualized therapeutic strategies targeted to improve morbidity and mortality and in general to improve patient-centered outcomes, 3. Early recognition and effective pre and post operative management of a patient with SDB, use of anaesthetics, towards patient safety and surgery outcomes, 4. Various types of sleep diagnostic test from type I to type IV and their use depending on patient profile, as well as their strengths and limitations.