Only be concerned with the number of pixels. Print DPI is just a setting you can change a document's print dpi to any value to want without resampling it just the size pixels will be printed. Pixels is where image details live you do not want to resample to so few pixels you loose all detail. Width is a parameter in the resizing tools like Image size, transform layer. If you transform a smart object layer too small you can recover. However resizing can be very destructive be careful.