CLCNKA and heart failure: At the CLCNKA locus for LVEF, we indicate HSPB7 (heat shock protein family B member 7) as a likely candidate given its recognized role in cardiogenesis by modulating actin filament assembly and known association with heart failure development.38–40 Decreased cardiomyocyte proliferation and abnormal sarcomere morphology were observed in HSPB7 knockout mice.