Echo Doppler principles, techniques and applications for the cardiac surgeon

Doppler echocardiography is increasingly used not only to identify disease in native heart valves, but also to assess the function of prosthetic valves. The purpose of this paper is to provide a summary of the principles of Doppler echocardiography for the cardiac surgeon which will lead to a discussion of assessment of prosthetic valve function. Solid cardiac structure imaging is first discussed in both one-dimensional (M-mode) and two-dimensional (B-mode) modalities. Measurements of blood cell velocities by conventional spectral Doppler echocardiography are then discussed, leading to two-dimensional flow imaging by color Doppler flow mapping. Assessment of prosthetic valve function is divided into two sections: normal prosthetic valve function and prosthetic valve dysfunction. Subtopics within each of these divisions are discussed in the context of conventional and color Doppler ultrasonography.