New modes of Doppler ultrasound and new signal conditioning of the received sonic spectra permit accurate assessments of velocities of intracardiac blood flow. Color-encoded, two-dimensional Doppler permits qualitative and quantitative evaluations of entire flow field velocity patterns. Studies utilizing these technologies include the following: 1) Doppler velocity/flow mapping in vivo and in vitro of clinical and preclinical prosthetic mitral valves; 2) comparison of in vivo Doppler ultrasound with in vitro Doppler ultrasound and laser Doppler anemometry; 3) assessment of mitral regurgitation; 4) quantitation of obstruction and regurgitation in right ventricular to pulmonary artery conduits. Studies in patients, both intraoperatively and postoperatively, have been initiated for assessment of operations for valvular lesions.
