Over all variability of mitral annular plane peak systolic velocity and peak global longitudinal strain rate in relation to age, body size, and sex: The HUNT Study.

BACKGROUND: Left ventricular (LV) systolic global function can be assessed by peak annular systolic velocity S'. Global longitudinal strain rate (GLSR) is relative LV shortening rate, equivalent to normalizing S' for LV length (S'n ). It has previously been shown that mitral annular plane systolic excursion (MAPSE) and global longitudinal strain (GLS) have similar biological variability, but GLS normalizes for one dimension only, inducing a systematic error, increasing body size dependence. The objective of this study was to compare S' with GLSR in the same way, comparing biological variability and body size dependence. METHODS AND RESULTS: A total of 1266 subjects from the third wave of Nord-Trøndelag Health Study (HUNT), without evidence of heart disease, were examined. Strain rate, S' and wall lengths were measured in the four walls of the two- and four-chamber views. Mean S' was 8.4 (1.4) cm/s, (S'n ) was 0.7 (0.14)s-1 and GLSR 1.02 (0.14)s-1 . All measures declined with age. Normalization of mitral annular velocities for LV length, or the use of GLSR, did not reduce overall biological variability compared with S'. S' did show a weak, positive correlation to BSA, while S'n and GLSR a slightly stronger, negative correlation to BSA. CONCLUSIONS: S', S'n , and GLSR have similar biological variability, which is mainly due to age, not body size variation. Normalizing S' for LV length (as in Sn or GLSR) reverses correlation with BSA inducing a systematic error, due to the one-dimensional normalization for one dimension only.

Relation between Mitral Annular Plane Systolic Excursion and Global longitudinal strain in normal subjects: The HUNT study.

BACKGROUND: Left ventricular (LV) systolic long-axis shortening can be measured as Mitral Annular Plane Systolic Excursion (MAPSE). Global longitudinal strain (GLS) is relative LV shortening, equivalent to normalizing MAPSE for LV length (MAPSEn). The objective of this study was to test whether normalizing LV shortening reduced biological variability of MAPSE due to normalizing for heart size and, possibly BSA. Secondly to provide normal reference values for MAPSE. METHODS AND RESULTS: A total of 1266 subjects from the Nord-Trøndelag Health Study (HUNT), without evidence of heart disease were examined. MAPSE and wall lengths were measured in all three standard apical views, while GLS has been published previously. Mean MAPSE was 1.58 (0.25) cm, MAPSEn 16.3 (2.4)%, and GLS 16.7 (2.4)%. All measures declined with age, correlations between -0.50 and -0.41. MAPSE was gender independent, and less BSA dependent than MAPSEn and GLS, while relative standard deviations (SDs) were similar for all three measures. CONCLUSIONS: MAPSE, MAPSEn, and GLS have similar biological variability, which is mainly due to age variation, indicating they are equivalent in normal, and normalizing for BSA will not reduce the variability. Normalizing MAPSE for LV length (MAPSEn and GLS) normalizes for one dimension only, inducing a systematic error, which increases BSA and gender dependence. Normal age-related, gender-independent values for MAPSE are provided.

Regional motion of the AV-plane is related to the cardiac anatomy and deformation of the AV-plane. Data from the HUNT study.

The study examines global and regional systolic shortening of the left (LV) and right ventricle (RV) in 1266 individuals without evidence of heart disease in the third wave of the HUNT study. Regional mitral annular systolic displacement (mitral annular plane systolic excursion [MAPSE]) was 1.5 cm in the septum and anterior walls, 1.6 cm in the lateral wall and 1.7 cm in the inferior wall, global mean 1.6 cm. Peak systolic velocity S' was 8.0, 8.3, 8.8 and 8.6 cm/s in the same walls (global mean 8.7 cm/s). All measures of LV longitudinal shortening correlated, mean MAPSE and S' also correlated with stroke volume (SV) and ejection fraction (EF). Global longitudinal strain by either method correlated with MAPSE, S' and EF, but not with SV, reflecting a systematic difference. S' and MAPSE correlated with early annular diastolic velocity (e'), reflecting that e' is the recoil from systole. Mean displacement was 2.8 (0.5) cm in the tricuspid annulus (tricuspid annular plane systolic excursion [TAPSE]). Normal values by age and sex are provided. Both TAPSE and S' were lower in women, where body size explained the sex difference. Normalisation of MAPSE and S' for wall length reduced intra-individual variation of displacement and velocity by 80%-90%, showing regional MAPSE to be related to LV wall length, and that longitudinal wall strain was relatively uniform. Displacement and S' were lowest in the septum and highest in the left and right free walls, shows systolic bending of the AV-plane into a U-shape, relating to the total cardiac volume changes during the heart cycle.

Importance of length and external diameter in left ventricular geometry. Normal values from the HUNT Study.

BACKGROUND: We aimed to study left ventricular (LV) geometry assessed by length (LVWL), external diameter (LVEDD) and relative wall thickness (RWT) in relation to age, body size and gender in healthy individuals. METHODS: 1266 individuals underwent echocardiography in the Nord-Trøndelag Health Study (HUNT3), Norway. Septum thickness (IVS), posterior wall thickness (LVPWd) and end-diastolic internal diameter (LVIDD) were measured in M-mode, and LVEDD was calculated as the sum. Myocardial wall lengths were measured in a straight line from apex to the mitral ring in apical views at end diastole and averaged to LVWL. RWT ([IVSd+LVPWd]/LVIDD) and the ratio between length and diameter (L/D) were calculated. RESULTS: Normal age-related and gender-related values are provided. Conventional measures conform to previous studies. All measures correlated with body surface area (BSA) (r 0.29-0.60), and BSA indexed values were higher in women. Wall thickness (WT) and LVEDD, but not LVIDD, were higher with higher age. LVWL and L/D were lower with increasing age, but L/D was independent of BSA and similar in women and men (1.41 vs 1.40). RWT correlated with BSA and age (r 0.17 and 0.34). CONCLUSIONS: LV WT increases and LVWL decreases with higher age. Excluding length in LV mass calculations increasingly overestimates mass with ageing. L/D is a BSA independent measure of LV age-related geometry and may be useful as a body size independent measure in LV hypertrophy. RWT depends on body size and age, and a single cut-off value is not warranted.