This study will use contrast echocardiography to assess the accuracy of a new non-invasive imaging method for subharmonic aided pressure estimation (SHAPE) compared to simultaneously acquired intra-cardiac pressures measured invasively during cardiac catheterization. This study is designed to verify that contrast echocardiography using the SHAPE method, already proven in a canine model and tested in a human pilot study can be used as a surrogate for cardiac catheterization with sufficient accuracy to allow clinical applicability in humans.