Echocardiographic Evaluation of Left Ventricular Filling Pressures Validated Against an Implantable Left Ventricular Pressure Monitoring System

Abstract

Aim of this study was to assess the ability of different echocardiographic indices to evaluate left ventricular (LV) filling pressures in patients with reduced LV function. In 5 patients scheduled for aortocoronary bypass surgery, a telemetric intraventricular pressure sensor was implanted. Over 6 months, these patients underwent a total of 21 echocardiographic examinations with a simultaneous recording of left ventricular mean (LVMDP) and end-diastolic pressure (LVEDP). The following echocardiographic parameters were extracted from the transmitral flow profile: early (E) and late (A) diastolic flow velocity, deceleration time of the E-wave (DT) and the isovolumic relaxation time (IVRT). Early diastolic velocity of the mitral ring (E') was recorded using pulsed-wave tissue Doppler echocardiography. All patients were in NYHA class III and mean ejection fraction was 30%. E correlated only moderately with LVMDP (r =-0.60, P = 0.003), but revealed the highest area under the receiver operating characteristic curve for the prediction of an elevated LVMDP > 12 mmHg (AUC = 0.94, sensitivity of 92% and specificity of 86%, cut-off value 7.5 cm/s). E/A > 1 predicted LVEDP > 15 mmHg with a sensitivity of 87% and a specificity of 80%. E/E' was not correlated with LVMDP or LVEDP. Although linear correlation between echocardiographic parameters and diastolic LV pressures reached statistical significance, the correlation coefficients were low. However, in these patients with severely reduced LV function due to ischemic heart disease conventional echocardiographic parameters of transmitral flow showed higher predictive values for elevated LV filling pressures than E/E'.