Intracardiac echocardiography: gross anatomy and magnetic resonance correlations and validations

The feasibility and safety of intracardiac echocardiography (ICE) in humans, using low frequency transducers, and its excellent tissue contrast capabilities that enhances the differentiation of intracardiac structures have been previously demonstrated. However, correlations among ICE imaging and anatomic sections or magnetic resonance (MR) scan planes have never been described before. This study was designed to correlate a simplified ICE approach with the anatomy of the right atrium and great vessels obtained by serial post-mortem sections and cardiac MR images.

A stepwise approach to ICE, which is based on our experience on over 300 consecutive patients with interatrial communications, has been correlated with anatomic sections from pressure-perfused-fixed hearts and spin echo cardiac MR imaging. A 9F-9 MHz mechanical device was used to record four transverse and one longitudinal sections for an extensive evaluation of the intracardiac architecture.

ICE transverse and longitudinal views allowed the detection of all the required information. Moreover, the anatomic sections and cardiac MR scan planes allowed validation of all the structures imaged by ICE. The potential clinical applications of the ICE technique are further discussed.

This paper demonstrates the basic accuracy of this new imaging modality. Therefore, mechanical ICE might be considered an active investment in cardiac catheterization laboratories, specifically in the percutaneous interventional procedure setting, discovering a new route (let's see and treat) to sophisticated interventions. In this respect, there can be little doubt that the knowledge of cross-sectional mechanical ICE imaging provides the basis for understanding the heart anatomy.