Impact of stroke volume on mitral annular velocities derived from tissue Doppler imaging: Figure 1

Mitral annular velocities derived from pulsed tissue Doppler imaging (TDI) were recently demonstrated to complement the analysis of systolic and diastolic left ventricular (LV) performance in different clinical settings.1,2 The early diastolic mitral annular velocity (E′) was found to behave as a preload independent index of relaxation.3 The mitral E/E′ ratio (that is, the mitral E velocity corrected for the influence of relaxation) has been suggested as an estimate of LV filling pressures.3 We hypothesised that LV stroke volume (SV) impacts on mitral annular velocities derived from TDI. Thus, mitral annular velocities should be altered in the presence of either increased or reduced SV. LV stroke volume index (SVI) was derived from biplane two dimensional images by subtracting LV end systolic volume from LV end diastolic volume, calculated by using Simpson’s rule. According to previously published normal values,4 expressed as mean (SEM), an SVI of 35.0 (6.8) ml/m2 (range 22–48 ml/m2) was considered normal for female subjects, and an SVI of 39.9 (6.0) ml/m2 (range 28–52 ml/m2) was considered normal for male subjects. Following these definitions, three study groups were separated. Group 1 comprised 19 patients with increased SVI (mean 62 (18) ml/m2), mean age …