Adding up to these findings, Kim et al. demonstrated that HSP60 levels are doubled in HF, and concurred in that the chaperonin is present embedded in the plasma membrane; furthermore, they mention that it is also found extracellularly, where it can activate apoptotic pathways on cardiomyocytes via TLR4 activation as previously described.69 Here, HSPD1 is linked to hydrops fetalis.