Determination of pressure gradient in the Hancock mitral valve from noninvasive ultrasound Doppler data

Abstract

The accuracy with which the pressure gradient in the Hancock mitral valve can be determined from noninvasive ultrasound Doppler data was explored in a study of eight adult patients. The mean manometric pressure gradient (ΔP_M) was determined by performing simultaneous left atrial and left ventricular catheterization. The mean diastolic pressure gradient was also determined from noninvasive ultrasound data (ΔPu). Identical cardiac cycles were used to compare ΔP_M and ΔPu. In the eight patients ΔP_M ranged from 3.0 to 9.0 mmHg and cardiac output from 3.7 to 5.5 l/min. The difference ΔP_M-ΔP_U was 0.3 ± 0.9 mmHg (mean ± SD). The results thus indicated that noninvasive ultrasound can determine the mean diastolic gradient in the Hancock mitral valve with an accuracy which approaches that attained with conventional manometric methods.

Key Words:

• Haemodynamics
• prosthetic mitral valve
• ultrasound Doppler