Possible Mechanisms Underlying Aging-Related Changes in Early Diastolic Filling and Long Axis Motion-Left Ventricular Length and Blood Pressure.

BACKGROUND: The transmitral E wave and the peak velocity of early diastolic mitral annular motion (e`) both decrease with age, but the mechanisms underlying these age-related changes are incompletely understood. This study investigated the possible contributions of blood pressure (BP) and left ventricular end-diastolic length (LVEDL) to age-related reductions in E and e`. METHODS: The study group were 82 healthy adult subjects <55 years of age who were not obese or hypertensive. Transmitral flow and mitral annular motion were recorded using pulsed-wave Doppler. LVEDL was measured from the mitral annular plane to the apical endocardium. RESULTS: Age was positively correlated with diastolic BP and septal wall thickness (SWT), inversely correlated with LVEDL (ß = -0.25) after adjustment for sex and body surface area, but was not related to left ventricular end-diastolic diameter (LVEDD). Age was also inversely correlated with E (r = -0.36), septal e`(r = -0.53) and lateral e`(r = -0.53). On multivariable analysis, E was inversely correlated with diastolic BP and LVEDD, septal e`was inversely correlated with diastolic BP and positively correlated with SWT and LVEDL, after adjusting for body mass index, whilst lateral e`was inversely correlated with diastolic BP and positively correlated with LVEDL. CONCLUSION: The above findings are consistent with higher BP being a contributor to age-related reductions in both E and e`and shortening of LVEDL with age being a contributor to the age-related reduction in e`. An implication of these findings is that slowing of myocyte relaxation is unlikely to be the sole, and may not be the main, mechanism underlying age-related decreases in E and e`.

Early changes in left ventricular long-axis function in Friedreich ataxia: relation with the FXN gene mutation and cardiac structural change.

OBJECTIVE: Friedreich ataxia (FRDA) is an autosomal recessive condition due to a GAA triplet expansion in the FXN gene that causes increased left ventricular (LV) wall thickness and can progress to LV systolic dysfunction. However, the changes in myocardial function that occur before a reduction in LV ejection fraction are incompletely understood. METHODS: LV long-axis function was assessed by measurement of tissue Doppler imaging (TDI) peak systolic (S`), early diastolic (E`), and atrial velocities (A`) at the septal and lateral borders of the mitral annulus in 60 subjects homozygous for a GAA expansion in the FXN gene who had preserved LV ejection fraction. Comparison was made with 60 sex- and age-matched controls. TDI velocities at 5 years were compared with baseline values in 17 FRDA subjects with follow-up studies who still had preserved ejection fraction. RESULTS: S` and E` were reduced in FRDA subjects at both the septal and the lateral mitral annular borders. Lateral E` was independently and inversely related to age, blood pressure, septal wall thickness, and the number of GAA repeats in the smaller allele of the FXN gene, whereas septal E` was not correlated with GAA repeat number. At 5 years, there was a reduction in lateral S` and E` but no change in septal TDI velocities. CONCLUSION: Subjects with FRDA have impairment of septal and lateral long-axis LV function, but there also seem to be regional differences in the effects of this condition that are at least partly related to the degree of genetic abnormality.

Factors associated with mitral annular systolic and diastolic velocities in healthy adults.

BACKGROUND: Measurements of systolic mitral annular velocity (S'), early diastolic mitral annular velocity (E'), and late diastolic mitral annular velocity (A') are used to assess left ventricular (LV) function. OBJECTIVE: We sought to investigate the relationship between septal and lateral annular velocities and determine whether these velocities are related to body size (including body mass index [BMI]), heart rate (HR), blood pressure, or LV mass. METHODS: A total of 60 healthy participants who were normotensive, between age 20 and 52 years, underwent standard echocardiography and measurement of septal and lateral S', E', and A'. RESULTS: The lateral velocity exceeded the septal velocity for S', E', and A'. There was only weak to moderate correlation between the velocities at the two sites (r = 0.43-0.60). Septal S' was positively correlated with height and HR, and lateral S' was correlated with HR. Septal E' was negatively correlated with age, BMI, LV mass, and diastolic blood pressure, but lateral E' was only negatively correlated with age and BMI. Septal A' was positively correlated with age, HR, and BMI, whereas lateral A' was only positively associated with age. CONCLUSIONS: S', E', and A' are not only of different magnitudes at the septal and lateral sites, but are not closely correlated. There are relationships between annular velocities and body size, HR, blood pressure, and LV mass that differ between the septal and lateral annulus, providing a possible explanation for the lack of close correlation in these velocities and suggesting that these variables may need to be considered when interpreting annular velocities.

Effect of preload reduction by haemodialysis on new indices of diastolic function.

Assessment of mitral annular motion diastolic velocities by M-mode or tissue Doppler imaging and the propagation velocity of early diastolic filling (Vp) by colour M-mode have been proposed as preload-independent indices of diastolic function. The aim of the present study was to determine the effects of preload reduction by haemodialysis on these new echocardiographic indices and to assess the relationship between these indices. The study group comprised 17 patients with chronic renal failure in sinus rhythm with normal left ventricular systolic function who underwent echocardiography 30 min prior to and 30 min following haemodialysis. Following dialysis there were significant reductions in weight (P<0.001), left atrial diameter (P=0.001), the peak Doppler velocity of early diastolic transmitral flow (P=0.005) and the ratio of Doppler velocities of early to late diastolic transmitral flow (P=0.02), consistent with a reduction in intravascular volume. There was no change after dialysis in early diastolic mitral annular velocity using M-mode (P=0.19) or tissue Doppler imaging from either the septal or lateral walls (P=0.88 and P=0.15 respectively), but there was a reduction in Vp after dialysis (55 to 49 cm/s; P=0.04). There were only weak correlations between Vp and the early diastolic mitral annular velocities (r<0.6 for all). We conclude that the assessment of diastolic function by the mitral annular early diastolic velocity appears to be preload-independent, that Vp may be affected by preload and that there is only a weak relationship between Vp and the early diastolic mitral annular velocity.

Mitral valve thrombus mimicking a primary tumor in the antiphospholipid syndrome.

Cardiac valvular abnormalities detected by echocardiography are relatively common in patients with the primary antiphospholipid syndrome. Valvular thickening with small vegetations are typical, but reports of lesion histology are rare. We report the case of a 50-year-old man presenting with thromboembolic phenomena who had a large (>2 cm), mobile, pedunculated, mass attached to the mitral valve that had the echocardiographic appearance of a primary valve tumor. Following surgical removal, histopathologic examination demonstrated pure fibrin thrombus and serological testing confirmed the antiphospholipid syndrome. This case highlights an unusual echocardiographic appearance of intracardiac thrombus in this syndrome.