Continuous-wave Doppler ultrasound assessment of peak pressure drop showed good correlation (r = 0.85) with invasive catheterization in patients with left ventricular outflow obstruction.
Observational (n=33)
Does Doppler ultrasound accurately estimate peak pressure drop compared to invasive catheterization in patients with left ventricular outflow obstruction?
Doppler ultrasound provides a reliable noninvasive method to estimate peak pressure drops and determine the level of obstruction in patients with left ventricular outflow obstruction.
Effect estimate: r = 0.85
Blood flow velocities in the left ventricle and the ascending aorta were recorded noninvasively with Doppler ultrasound. The ultrasound beam was aligned as much as possible to the direction of velocity, using the frequency shift in the audio signal as a guide to obtain velocities as close as possible to those present. From the maximal velocity recorded by continuous-wave Doppler, a peak pressure drop was calculated in 24 patients with aortic valve stenosis and nine with fixed subaortic stenosis. Fourteen patients with aortic stenosis and three with fixed subaortic stenosis were catheterized. In these patients, the correlation between calculated pressure drops and those obtained by pressure recording was good (r = 0.85). The pressure drop can be underestimated by underestimating velocity, but cannot be overestimated. With pulsed Doppler, the level of obstruction can be determined.
Liv Hatle (1981) conducted an observational in Left ventricular outflow obstruction (aortic valve stenosis and fixed subaortic stenosis) (n=33). Doppler ultrasound vs. Catheterization was evaluated on Correlation between calculated pressure drops and those obtained by pressure recording (r = 0.85). Continuous-wave Doppler ultrasound assessment of peak pressure drop showed good correlation (r = 0.85) with invasive catheterization in patients with left ventricular outflow obstruction.