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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Contrast Media, Data Interpretation, Statistical, Echocardiography, Doppler, Elastic Modulus, Elasticity Imaging Techniques, Female, Heart Ventricles, Humans, Image Enhancement, Image Interpretation, Computer-Assisted, Magnetic Resonance Imaging, Cine, Male, Myocardial Contraction, Reference Values, Reproducibility of Results, Sensitivity and Specificity, Signal Processing, Computer-Assisted, Ventricular Function.
user
Are longitudinal myocardial peak velocities using high temporal resolution phase-contrast and simple averaging comparable to tissue Doppler echocardiography? Context: Phase contrast imaging is widely used to measure blood velocity. However tissue Doppler imaging (TDI) echocardiography is the reference for myocardial velocity assessment. This study aims at validating the ability of phase contrast (PC) sequences to correctly assess myocardial velocities and to compare these velocities to TDI. The phase contrast sequence was performed with breath-hold parameters and with parameters tuned to increase temporal resolution in free breathing. Left and Right auriculo-ventricular annuluses longitudinal velocities were recorded on six healthy volunteers with different temporal resolutions (TDI: 5 ms, breath-hold PC: 94 ms and free-breathing PC: 19 ms). Free-breathing PC was obtained by averaging of three excitations. Amplitudes of four standard echocardiographic and clinically relevant myocardial longitudinal velocity waves were compared: Early filling and auricular, systolic and isovolumic contractions. Isovolumic contraction waves were only visible with free-breathing PC and TDI. The differences with the reference TDI wave velocities were lower (p = 0.02) for free-breathing PC (19.2 ± 2.6%) than for breath-hold PC (28.1 ± 2.9%). These differences for free-breathing PC were close to (p = 0.21) the coefficient of variation of the measurements provided by TDI (14.8 ± 1.2%).
assistant
Myocardial longitudinal peak velocities can be assessed with a PC sequence tuned to optimize temporal resolution. Final Decision: yes