The invention provides a method of identifying candidate agents to test for treating heart failure involving diastolic impairment, the method comprising: testing an agent to determine whether it (a) binds to serum response factor (SRF), (b) reduces SRF binding to a serum response element (SRE), or (c) reduces SRF protein levels in a cell; wherein if the agent does one or more of (a), (b), and (c), it is identified as a candidate agent.