Intracardiac echocardiography allows excellent resolution images because high frequency transducers can be used in close proximity to the structures being imaged. High frequency signals, though providing high resolution, have poor depth penetration. But since intracardiac echocardiography signals need not travel large distances as the structures are quite near to the transducer. Superb anatomical details may be obtained to help in the diagnosis of complex cardiac abnormalities. The intracardiac echocardiography transducer is enclosed in an acoustic housing at the distal end of the catheter used for introducing it into the cardiac chambers. Just as in intravascular ultrasound (IVUS), 360 degree imaging is possible. The images are cross-sectional with the catheter in the centre, just as in IVUS. It is also possible to deflect the catheter tips in certain models which allow easy manipulation within cardiac chambers. It has Doppler facility for evaluating blood flow velocity as well as tissue velocity. Intracardiac echocardiography is being increasingly used to guide radiofrequency ablations and septal punctures for electrophysiology work. It is useful in evaluating aortic aneurysms and stent grafts. Intracardiac echocardiography has also been used recently to aid complex surgical procedures for congenital heart disease and structural heart diseases.