Transmitral Doppler assessment of left ventricular diastolic function during coronary artery bypass surgery

To evaluate which Doppler transmitral velocity indices of left ventricular diastolic function change with alteration of left ventricular filling pressure.

Twenty-two patients undergoing coronary artery bypass surgery. The effect of fluid loading on indices derived from the transmitral Doppler waveform, recorded by a trans-oesophageal echocardiography, was evaluated using a generalised linear statistical model.

E-wave maximum velocity, E-wave acceleration time and slope, E-wave deceleration slope, A-wave maximum velocity and E/A wave maximum velocity ratio showed significant changes after alterations in left ventricular filling pressure. E-wave deceleration time and E-wave maximum velocity/time velocity integral showed no significant change after fluid loading.

Several commonly used Doppler derived indices of left ventricular diastolic function are significantly affected by changes in filling pressure of the left ventricle. This may limit the usefulness of the Doppler method for serial assessment of diastolic function when the left ventricular filling pressure has changed between assessments. Only the E-wave deceleration time did not show significant changes and might be a useful Doppler index for the serial measurement of left ventricular compliance but this needs to be confirmed with haemodynamic measurements.