OBJECTIVES:   Unexplained Syncope patients have 1.6 times the mortality risk of the average population. The “Eastbourne Syncope Assessment Study” (EaSyAS; Farwell 2004) is an RCT which demonstrated a significantly higher diagnostic yield in unexplained syncope patients using ILRs (Reveal, Medtronic) (34/101 Patients diagnosed (33.7%) versus a conventional diagnostic strategy (4/97 Patients diagnosed (4.1%); p<0.001) after a mean follow-up period of 9 months. The study also included detailed health care utilisation analysis, ultimately demonstrating a reduced cost-per-correct-diagnosis under the UK setting and significant reductions in the overall volume of diagnostic tests. We sought to explore potential cost implications of ILR use in this patient population, from the perspective of the French Social Security. METHODS: We used EaSyAS to assess the type and volume of diagnostic tests used. Direct medical costs were derived from the 2008 CCAM Procedure Tariff and DRG Tariff. Reveal selling price was used to assess ILR cost.  RESULTS: The cost of a successfully diagnosing an unexplained syncope patient with Reveal is 4.7 times lower than the equivalent cost using a conventional strategy. This allows for a moderate ICER equal to €2535.60 on a cost-per-diagnosis basis.Two univariate sensitivity analysis on the device cost and the procedures cost showed little impact on the ICER. CONCLUSIONS: Although this analysis was based on UK short term data, its results are consistent with analyses performed in other developed countries. The analysis demonstrated an ICER below €4,000 on a cost-per-diagnosis basis. This could mean that ILR use in France has the potential for significant cost-savings in this patient population. The upcoming FREnch Syncope study on Holter monitoring (FRESH) should allow for a more precise assessment of cost-savings achieved with ILRs in France.