In this work, comprehensive high resolution EM-simulations were performed for three different 16-element transmit/receive (Tx/Rx) planar RF coil arrays loaded with the anatomical Duke human model to examine their performance in cardiac magnetic resonance imaging (cMRI) at 7T. An optimization routine has been developed in MATLAB to optimize the phases for B1+ field homogeneity with minimal local SAR values within the Duke human biological model. Before B1-shimming, all arrays demonstrated approximately the same B1+ field distributions with a pronounced higher field values near to the coil surface. With phase increments of 45° phase shift between each of the 8-element pairs, the arrays generate pronounced local SAR hot spots with maximum values of 10.3, 10.1, and 9.4 W/kg for design 1, 2 and 3, respectively. In accordance with IEC regulations, the calculated 10 g averaged SAR values were found to be within the limits and the relative hot spots were found to be below 11 W/kg. RF shimming improves the B1+ field homogeneity by 24%, 49% and 40% in the central sagittal slice for design 1, 2 and 3, respectively.