Pré-publication, Document de travail: The role of innovative procedures in the mortality differences between university, non-teaching public and for-profit hospitals is investigated using a French exhaustive administrative dataset on patients admitted for heart attack. Mortality is roughly similar in the three types of hospitals after controlling for case-mix. For-profit hospitals treat the at-risk oldest patients more often with innovative procedures. Therefore, additionnally controlling for innovative procedures makes them having the highest mortality rate. Non-teaching public hospitals end up having the lowest mortality rate.