In any case, further studies focused on the determination of HO-1 expression levels in cardiac tissue in advanced phases of SSc need to be conducted, as well as the investigation of the effects of CO in endogenous cardiac Kv7.1 where it is co-expressed with the auxiliary subunit KCNE1 and KCNE2 (Plant et al., 2014). This evidence concerns the gene HMOX1 and systemic sclerosis.