An experimental study is reported which investigates the wall shear stress (WSS) distribution in a transparent model of the human aorta comparing a SJM Regent bileaflet mechanical heart valve (BMHV) with the Lapeyre-Triflo FURTIVA trileaflet mechanical heart valve (TMHV) in physiological pulsatile flow. Elastic micro-pillar structures, calibrated as WSS sensors by micro-Particle-Image-Velocimetry measurement, are applied to the wall along the ascending aorta (AAo). The peak WSS values in the BMHV are observed to be almost twice that of the values seen in the TMHV. Flow field analysis illuminates that these peaks are linked to the jet-like flows generated in the valves interacting with the aortic wall. Not only the magnitude, but also the impact regions are specific for different valve designs. The side-orifice jets generated by the BMHV travel along the aortic wall in the AAo, impacting the wall throughout the AAo. Whereas the jets generated by TMHV impact further downstream in the AAo and results in a reduced WSS.