Therapeutic inhibition of RBM20 improves diastolic function in a murine heart failure model and human engineered heart tissue.

Heart failure with preserved ejection fraction (HFpEF) is prevalent and deadly, but so far, there is no targeted therapy. A main contributor to the disease is impaired ventricular filling, which we improved with antisense oligonucleotides (ASOs) targeting the cardiac splice factor RBM20. In adult mice with increased wall stiffness, weekly application of ASOs over 2 months increased expression of compliant titin isoforms and improved cardiac function as determined by echocardiography and conductance catheter.