Transthoracic coronary Doppler vibrometry in the evaluation of normal volunteers and patients with coronary artery stenosis

Quest for the Vulnerable Atheroma: Carotid Stenosis and Diametric Strain--A Feasibility Study

The Bernoulli effect may result in eruption of a vulnerable carotid atheroma, causing a stroke. We measured electrocardiography (ECG)-registered QRS intra-stenotic blood velocity and atheroma strain dynamics in carotid artery walls using ultrasonic tissue Doppler methods, providing displacement and time resolutions of 0.1 μm and 3.7 ms. Of 22 arteries, 1 had a peak systolic velocity (PSV) >280 cm/s, 4 had PSVs between 165 and 280 cm/s and 17 had PSVs <165 cm/s. Eight arteries with PSVs <65 cm/s and 4 of 9 with PSVs between 65 and 165 cm/s had normal systolic diametric expansion (0% and 7%) and corresponding systolic wall thinning. The remaining 10 arteries had abnormal systolic strain dynamics, 2 with diametric reduction (>-0.05 mm), 2 with extreme wall expansion (>0.1 mm), 2 with extreme wall thinning (>-0.1 mm) and 4 with combinations. Decreases in systolic diameter and/or extreme systolic arterial wall thickening may indicate imminent atheroma rupture.

Development of an interactive Coronary Doppler Vibrometry system for detection of coronary artery disease

Coronary artery disease is a deadly and costly condition and represents an important public health issue globally. Coronary Doppler vibrometry (CDV), a new noninvasive coronary artery stenosis detection technique, showed encouraging results in our recent clinical study. However, the CDV system required lengthy offline data analysis, thus it did not provide any feedback during examination on the quality of data, not to mention analysis results. To overcome these limitations, we have developed a new CDV system that interactively performs acquisition, analysis and display of a complete data set while a subject is still on the examination table. Our system is based on a commercial ultrasound machine, and it will be a useful tool for CDV research and clinical studies in the future.