Pulmonary valve. This valve is difficult to image so not visualizing it well isn't necessarily meaningful.
Depends on test. The terminology that the pulmonivc valve is not well visualized usually refers to the echocardiographic exam. This test uses sound waves to visualize the heart and measure pressures and structures, because of the location of the pulmonic valve, the sound waves often are unable to acquire a detailed picture of this valve. It simply means it could not be seen and does not imply any pathology.