**1. Introduction**

Dilated cardiomyopathy (DCM) is a heterogeneous primary muscle disease predominantly affecting men, with a male to female ratio 3:1. The prognosis of DCM has dramatically improved over

the last decades [1–3] and the occurrence of left ventricular reverse remodelling (LVRR) under optimal medical treatment has been shown as one of the main prognostic drivers [1,4,5].

Female sex has recently emerged as an important outcome modifier in DCM patients, being independently associated with more favourable long-term outcomes and with a lower incidence of cardiovascular events in comparison to the male counterpart [6–8]. However, little is known regarding the mechanism underlying this important sex-specific effect. So far, none of the available reports have evaluated whether this difference could be partially explained by a different response to treatment and a more frequent occurrence of LVRR in women.

The aim of the present study was to investigate the rates of LVRR in males and females, and the prognostic impact of the relationship between LVRR and sex in a well-selected large cohort of real-world DCM patients with a long-term follow-up.
