Described herein is an intracardiac ultrasound catheter (IUC) with an enlarged distal end comprising an enlarged ultrasound transducer array for improved imaging. In some embodiments, the distal end and transducer array are foldable. In some embodiments, the transducer array is two-dimensional. The transducer array can be side-firing or end-firing. In some embodiments, the transducer array can be covered in its folded position by a catheter housing. In some embodiments, the transducer array can be covered in its folded position by a retractable distal end cover.
