Patients included in the study will be monitored and followed for a minimum of one year and a maximum of three years. Patients will be examined at the time of inclusion (T0), after one month (T1), three months (T2), six months (T3), 12 months (T4) and every six months thereafter, if applicable, during the follow-up period. Evaluations will include; i)new episodes of ACS, stroke, TIA, heart failure, hospitalization for cardiovascular causes and cardiovascular mortality, ii) biological risk markers involved in cardiovascular complications, iii) an evaluation of the cost-effectiveness of diagnosis and CPAP treatment in patients with ACS who have obstructive sleep apnea.