Haematocrit profoundly affects left ventricular diastolic filling as assessed by Doppler echocardiography

Background The main determinants of diastolic function - pre- and afterload of the heart - are affected by the haematocrit, but the relation between h aematocrit and diastolic function is unclear. Objective To study the association between interindividual haematocrit valu es end diastolic function, by echocardiography. Design In a cross-sectional survey, blood pressure, haematocrit values, and high-quality Doppler indexes of left ventricular filling were obtained in 1297 individuals, 25-74 years of age, and analysed by regression analyses. Results Haematocrit and systolic blood pressure were strongly correlated (r = 0.23; P < 0.0001). Moreover, haematocrit was inversely correlated with t he peak velocity of early left ventricular filling and with the peak veloci ty of early filling divided by late filling (E/A ratio; both P < 0.005). Le ft ventricular isovolumic relaxation time (IVRT) was positively associated with haematocrit (r = 0.18, P < 0.001). In individuals with an abnormal Dop pler filling pattern (E/A(<50years) < 1, E/A(>50years) < 0.5, or IVRT<30yea rs > 92 ms, IVRT30-50years > 100 ms or IVRT>50years > 105 ms; n = 119), gre ater haematocrit values were observed than in those with normal diastolic p arameters (P < 0.001). Conversely, individuals with an increased haematocri t (> 50% in men, > 45% in women; n = 16) had a greater risk of presenting w ith abnormal left ventricular filling (31.3%) compared with individuals wit h normal (12.1%; n - 898;) or low (< 40% in men, < 35% in women: 10.5%, n = 38; P = 0.07) haematocrit Strong and significant associations between haem atocrit and Doppler indexes of left ventricular filling were confirmed afte r adjustment for multiple potential confounders including blood pressure, a ntihypertensive medication and body mass index. Similarly, blood pressure a nd parameters of diastolic filling were strongly associated correlations th at were not affected by inclusion of haematocrit values into the regression model. Conclusion The data point to substantial adaptations of diastolic filling i n response to both blood pressure and the characteristics of the medium tha t is propelled by the heart. Therefore, in addition to blood pressure value s, the variability of haematocrit values should be considered when diastoli c function is being evaluated by Doppler echocardiography. J Hypertens 18:1 483-1489 (C) 2000 Lippincott Williams & Wilkins.