Changes of calcium cycling in HFrEF and HFpEF.

Dysfunctions of calcium cycling occur in heart failure with reduced and preserved ejection fraction (HFrEF and HFpEF). HFrEF and HFpEF showed Ca leakage at diastole. The compensation of Na/Ca exchanger and the decrease of T-tubule density reduces cytoplasmic Ca concentration in HFrEF and impairs systolic function. In contrast, HFpEF has the increase of cytoplasmic Ca concentration and diastolic dysfunctions. The decrease of mitochondrial Ca concentration weakens myocardial contractility in HFrEF while the increased concentration retains the contractility in HFpEF. Here, the changes of calcium cycling in HFrEF and HFpEF are summarized and the possibility of relevant therapeutic targets is discussed.