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 haematocrit and diastolic function is unclear. OBJECTIVE: To study the association between interindividual haematocrit values and 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 the peak velocity of early left ventricular filling and with the peak velocity of early filling divided by late filling (E/A ratio; both P< 0.005). Left ventricular isovolumic relaxation time (IVRT) was positively associated with haematocrit (r= 0.18, P< 0.001). In individuals with an abnormal Doppler filling pattern (E/A(< 50 years) < 1, E/A(> 50 years) < 0.5, or IVRT(< 30 years) > 92 ms, IVRT30-50 years > 100 ms or IVRT> 50 years > 1 05 ms; n = 119), greater haematocrit values were observed than in those with normal diastolic parameters (P< 0.001). Conversely, individuals with an increased haematocrit (> 50% in men, > 45% in women; n = 16) had a greater risk of presenting with abnormal left ventricular filling (31.3%) compared with individuals with 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 haematocrit and Doppler indexes of left ventricular filling were confirmed after adjustment for multiple potential confounders including blood pressure, antihypertensive medication and body mass index. Similarly, blood pressure and parameters of diastolic filling were strongly associated correlations that were not affected by inclusion of haematocrit values into the regression model. CONCLUSION: The data point to substantial adaptations of diastolic filling in response to both blood pressure and the characteristics of the medium that is propelled by the heart Therefore, in addition to blood pressure values, the variability of haematocrit values should be considered when diastolic function is being evaluated by Doppler echocardiography.

Familial predisposition of left ventricular hypertrophy.

OBJECTIVES: The study evaluated the contribution of familial predisposition to the risk of left ventricular hypertrophy (LVH). BACKGROUND: Left ventricular hypertrophy is a multifactorial condition that serves as an important predictor of cardiovascular mortality. At present it is unclear whether familial predisposition contributes to the manifestation of LVH. Thus, we determined whether siblings of subjects with LVH are at increased risk to present with an elevation of LV mass or an abnormal LV geometry. METHODS: Echocardiographic and anthropometric measurements were performed in 2,293 individuals who participated in the echocardiographic substudies of population-based MONICA Augsburg surveys. In addition, a total of 319 siblings of survey participants with echocardiographic evidence of LVH were evaluated. The risk of these siblings to present with LVH or abnormal LV geometry was estimated by comparison with 636 subjects matched for gender and age that were selected from the entire echocardiography study base. RESULTS: Blood pressure, body mass index, age, and gender (i.e., known determinants of LV mass) were comparable in LVH-siblings and the matched comparison group. However, septal and posterior wall thicknesses, relative wall thickness as well as LV mass index were significantly elevated in LVH-siblings (p < 0.001, each) whereas LV dimensions did not differ. Likewise, the prevalence of LVH was raised in LVH-siblings, as was the relative risk of LVH after adjustment for confounders (p < 0.05). More specifically, LVH-siblings displayed increased prevalences of concentric remodeling and concentric LVH (p < 0.05) but not of eccentric LVH. CONCLUSIONS: Familial predisposition appears to contribute to increased LV wall thickness, to the development of LV hypertrophy and abnormal LV geometry.

Lack of association between a polymorphism of the aldosterone synthase gene and left ventricular structure.

BACKGROUND: Cardiac growth and function may be modulated in part by trophic effects of neurohormones. Specifically, aldosterone has been shown to stimulate the growth of cardiac myocytes and the accumulation of cardiac extracellular matrix proteins. Moreover, a variant of the aldosterone synthase gene (a cytosine/thymidine exchange at position -344 in the transcriptional regulatory region) has been associated with enlargement and disturbed filling of the left ventricle (LV) in a small sample of young white adults. The aim of the present study was to reinvestigate the implications of aldosterone synthase -344C/T allele status for serum aldosterone levels, blood pressure, and LV structure and function in large population-based samples. METHODS AND RESULTS: Individuals who participated in the echocardiographic substudy of the third MONICA (MONitoring trends and determinants in CArdiovascular disease) survey (n=1445) or in the second follow-up of the first MONICA survey (n=562) were studied by standardized anthropometric, echocardiographic, and biochemical measurements as well as genotyping for aldosterone synthase -344C/T allele status. In both surveys, the distribution of sex, age, arterial blood pressure, and body mass index was homogeneous in the aldosterone synthase genotype groups. Echocardiographic LV wall thicknesses, dimensions, and mass indexes were not significantly associated with a specific aldosterone synthase genotype. Likewise, no association was detectable with echocardiographic measures of LV systolic or diastolic function. Data were consistent in both samples and not materially different in subgroups defined by age, sex, or intake of antihypertensive medication. Finally, no significant association was observed for aldosterone synthase allele status and serum aldosterone levels in the group of 562 individuals. CONCLUSIONS: The data are not in favor of a significant contribution of the C/T exchange at position -344 in the aldosterone synthase transcriptional regulatory region to the variability of serum aldosterone levels, blood pressure, or cardiac size or function as found in 2 white population-based samples.

Assessment of left ventricular diastolic filling in arterial hypertension: comparison of pulsed Doppler echocardiography and acoustic quantification.

We compared acoustic quantification (AQ) to Doppler echocardiography (DE) in the evaluation of left ventricular (LV) diastolic filling in 41 hypertensives and 42 controls. In hypertensives, DE showed reduced ratios of early to late diastolic velocity, AQ revealed reduced peak to late filling rate ratios, and both techniques found prolonged acceleration times indicating abnormal filling. In 22 patients with mild hypertension and less LV hypertrophy, however, all DE filling parameters were normal. In these patients AQ indicated prolonged acceleration times and early filling times. In conclusion, AQ is useful for the identification of abnormal LV filling in arterial hypertension and might be superior to DE in detection of early diastolic dysfunction.

Changes in left ventricular structure and function in patients with white coat hypertension: cross sectional survey.

OBJECTIVES: To assess the relation between white coat hypertension and alterations of left ventricular structure and function. DESIGN: Cross sectional survey. SETTING: Augsburg, Germany. SUBJECTS: 1677 subjects, aged 25 to 74 years, who participated in an echocardiographic substudy of the monitoring of trends and determinants in cardiovascular disease Augsburg study during 1994-5. OUTCOME MEASURES: Blood pressure measurements and M mode, two dimensional, and Doppler echocardiography. After at least 30 minutes' rest blood pressure was measured three times by a technician, and once by a physician after echocardiography. Subjects were classified as normotensive (technician <140/90 mm Hg, physician <160/95 mm Hg; n=849), white coat hypertensive (technician <140/90 mm Hg, physician >=160/95 mm Hg; n=160), mildly hypertensive (technician >=140/90 mm Hg, physician <160/95 mm Hg; n=129), and sustained hypertensive (taking antihypertensive drugs or blood pressure measured by a technician >=140/90 mm Hg, and physician >=160/95 mm Hg; n=538). RESULTS: White coat hypertension was more common in men than women (10.9% versus 8.2% respectively) and positively related to age and body mass index. After adjustment for these variables, white coat hypertension was associated with an increase in left ventricular mass and an increased prevalence of left ventricular hypertrophy (odds ratio 1.9, 95% confidence interval 1.2 to 3.2; P=0.009) compared with normotensive patients. The increase in left ventricular mass was secondary to significantly increased septal and posterior wall thicknesses whereas end diastolic diameters were similar in both groups with white coat hypertension or normotension. Additionally, the systolic white coat effect (difference between blood pressures recorded by a technician and physician) was associated with increased left ventricular mass and increased prevalence of left ventricular hypertrophy (P<0.05 each). Values for systolic left ventricular function (M mode fractional shortening) were above normal in subjects with white coat hypertension whereas diastolic filling and left atrial size were similar to those in normotension. CONCLUSION: About 10% of the general population show exaggerated inotropic and blood pressure responses when mildly stressed. This is associated with an increased risk of left ventricular hypertrophy.

Neurohormonal activity and left ventricular geometry in patients with essential arterial hypertension.

The purpose of this study was to investigate whether the basal activity of the renin-angiotensin-aldosterone system or the basal levels of the atrial natriuretic peptide (ANP) are related to distinct patterns of left ventricular (LV) geometry in patients with essential hypertension. The left ventricle of patients with arterial hypertension may be exposed to a variety of growth-regulating mechanisms, including pressure overload and humoral activation. The interaction of such growth stimuli may be involved in the modulation of LV geometry. LV geometry was determined echocardiographically in 104 patients with mild to moderate essential hypertension. The same number of age- and sex-matched normotensive subjects served as controls. Plasma renin activity (PRA) and serum concentrations of aldosterone and ANP were measured by radioimmunoassay. Correlation analyses revealed that PRA was significantly associated with septal wall thickness and LV mass index (r = 0.25; p < 0.005 each). In addition, as compared with normal subjects (1.0 +/- 0.7 ng/ml/hr), PRA was significantly increased in patients with concentric LV hypertrophy (LVH) (3.4 +/- 6.6 ng/ml/hr, p < 0.01). Aldosterone displayed a close correlation with septal, posterior, and relative wall thickness (r > 0.27, p < 0.005 each). Compared with normal subjects (74 +/- 27 pg/ml), patients with hypertension and pathologic patterns of LV geometry were characterized by elevations of aldosterone (LV remodeling 203 +/- 93 pg/ml, concentric LVH 123 +/- 67 pg/ml; eccentric LVH 199 +/- 89 pg/ml; p < 0.05 each). ANP was significantly associated with septal wall thickness, left ventricular dimension, and LV mass index (r > 0.22, p < 0.005 each). Furthermore, compared with normal subjects (50 +/- 17 pg/ml), ANP values were significantly increased in patients with hypertension and concentric LVH (80 +/- 44 pg/ml, p < 0.005) and eccentric LVH (88 +/- 24 pg/ml, p < 0.001). Multivariate analysis adjusting for systolic blood pressure, body mass index, and age revealed that renin and ANP were independently associated with LV mass index (p < 0.05 each). Interestingly, adjusted PRA levels were not related to any specific pattern of LV geometry. In contrast, adjusted ANP levels were associated with concentric and eccentric LVH, whereas adjusted aldosterone levels were significantly elevated in subjects with LV remodeling and eccentric LVH (p < 0.005). Thus elevated levels of renin and ANP may be found in patients with hypertension and elevated LV mass index. In addition, ANP and aldosterone are related to specific geometric patterns of the left ventricle. The data may further stimulate the discussion on the mechanisms that account for alterations of LV geometry in hypertension.