Peak early diastolic mitral annulus velocity by tissue Doppler imaging for the assessment of left ventricular relaxation in subjects with mitral annulus calcification

Abstract

Aims: The aim of this article was to determine whether lateral and septal early diastolic mitral annular velocities (LW-e' and IS-e', respectively) accuracy to reflect left ventricular (LV) relaxation is truly compromised by a limitation of mitral annular motion due to mitral annulus calcification (MAC) and to search for e' surrogates to circumvent this limitation.

Methods and results: LW-e', IS-e', and peak early diastolic velocities at the basal-lateral and basal-septal LV segments 2 cm distal to the annulus (LW-e'2 and IS-e'2, respectively) were measured using tissue Doppler imaging (TDI) in 206 consecutive patients referred for echocardiography. Significant MAC (assessed by two-dimensional echocardiography) was present in 57 (28%) subjects. There was a significant reduction in LW-Δe' (LW-e' minus LW-e'2) in subjects with posterior MAC (0.15 ± 1.35 vs. 1.30 ± 1.24 cm/s, P < 0.0001) and a small but not significant reduction in IS-Δe' (IS-e' minus IS-e'2) in subjects with anterior MAC (-0.15 ± 1.04 vs. 0.42 ± 1.56 cm/s, P = 0.07), compared with age-matched no MAC subjects. Potential confusion factors were analysed on multiple regression. The basal segments in which e'2 were measured were free of calcification regardless of MAC. In search for e'2-based surrogates for e', the regression equation [Formula: see text] (R(2) = 0.86, P < 0.0001) was obtained from the first 100 consecutive subjects and validated in the next 49 no MAC subjects (intraclass correlation coefficient 0.96, P < 0.0001). In the septal side, no difference was found between IS-e' and IS-e'2 in the 149 subjects with no MAC (8.5 ± 3.1 vs. 8.5 ± 2.9 cm/s, P = 0.55).

Conclusion: MAC significantly affected LW-e' (and not significantly IS-e') accuracy to reflect LV relaxation. [Formula: see text] and IS-e'2 as surrogates for LW-e' and IS-e', respectively, may correct this inaccuracy.

Keywords: Early diastolic mitral annular velocity; Left ventricular longitudinal myocardial relaxation; Mitral annulus calcification; Tissue Doppler imaging.