In cases of Dilated Cardiomyopathy, there is a known decrease in contractile output due to the thinned walls of the left ventricle. Research is currently looking for ways to increase this contractile force and improve the efficiency of the heart. The ultimate question is, how can one increase contractility. Calcium, an ion known to be involved in muscle contraction, is found in cardiomyocytes. One way to increase force output is to utilize calcium by preventing its movement out of the cell. This project looks at the Sodium Potassium (NKA) pump, a protein that moves sodium and potassium across the cell membrane, and its effect on calcium movement out of the cell. As these ions are moving, there is a change in electrical charges which influences other ions, such as calcium, to move out of the cell. The theory, then, is to find a way to inhibit the NKA pump, preventing its movement of calcium out of the cell and allowing calcium to aid in the contraction of the heart. To inhibit the NKA pump, this project utilizes Phospholemmon (PLM), which has been show to inhibit NKA function and prevent the ions from moving against a concentration gradient. The goal is then to assess how closely these two proteins (NKA and PLM) bind to one another, as tighter binding can lead to greater inhibition of the NKA pump. The binding affinity is assessed by fluorescently tagging these two proteins and quantifying their difference in binding using Fluorescence Resonance Energy Transfer (FRET) Microscopy. To further this project, known disease-causing mutations of PLM were identified and investigated to determine the mutation that shows the greatest inhibition of the NKA pump, leading to the greatest increase in contractility of dilated cardiomyopathy hearts.