Doppler echocardiographic parameters of LV diastolic function (isovolumic relaxation time, E wave velocity, ratio of E/A wave velocities, mitral valve pressure half time) were compared to catheter data in 35 patients (average age 67 years) with pure or dominant aortic stenosis (mean gradient: 65 +/- 30 mmHg). The isovolumic relaxation time was prolonged in most patients (m = 103 +/- 23 ms) and seemed uninfluenced by any haemodynamic parameter. There was a positive correlation between pressure half time and ejection fraction (r = 0.41, p = 0.02) and a negative correlation with pulmonary capillary pressure (r = -0.61, p < 0.01). The E and E/A ratio were negatively correlated with the ejection fraction (r = -0.41 and -0.52) and positively correlated with pulmonary capillary pressure (r = 0.46 and 0.62). The Doppler parameters were independant of the patients' age, severity of stenosis and degree of left ventricular hypertrophy. Patients with normal pulmonary capillary pressure (< 15 mmHg, N = 19) had abnormal diastolic filling with low E wave velocities (71 +/- 28 cm/s) and E/A ratios (0.9 +/- 0.6) and prolonged half pressure times (96 +/- 37 ms). Conversely, patients with high pulmonary capillary pressures (> 15 mmHg, N = 16) had normal or high E wave velocities (107 +/- 31 cm/s) and E/A ratios (1.5 +/- 0.6) and normal or shortened isovolumic relaxation times (62 +/- 22 ms).(ABSTRACT TRUNCATED AT 250 WORDS)