Although absence of DWORF does not exacerbate PLN-R14del cardiomyopathy in mice, it is of importance to note that PLN-R14del cardiomyopathy has a distinct disease mechanism compared with other HF etiologies, including abnormal S/ER clustering (8) which, to our knowledge, has not been observed in other types of HF. Here, PLN is linked to hydrops fetalis.