Prevalence of left ventricular diastolic dysfunction in a general population

BACKGROUND: Because the process of myocardial remodelling starts before the onset of symptoms, recent heart failure (HF) guidelines place special emphasis on the detection of subclinical left ventricular (LV) systolic and diastolic dysfunction and the timely identification of risk factors for HF. Our goal was to describe the prevalence and determinants (risk factors) of LV diastolic dysfunction in a general population and to compare the amino terminal probrain natriuretic peptide level across groups with and without diastolic dysfunction. METHODS AND RESULTS: In a randomly recruited population sample (n=539; 50.5% women; mean age, 52.5 years), we measured early and late diastolic peak velocities of mitral inflow (E and A), pulmonary vein flow by pulsed-wave Doppler, and the mitral annular velocities (Ea and Aa) at 4 sites by tissue Doppler imaging. A healthy subsample of 239 subjects (mean age, 43.7 years) provided age-specific cutoff limits for normal E/A and E/Ea ratios and the differences in duration between the mitral A and the reverse pulmonary vein flows during atrial systole (DeltaAd-ARd). The number of subjects in diastolic dysfunction groups 1 (impaired relaxation), 2 (elevated LV end-diastolic filling pressure), and 3 (elevated E/Ea and abnormally low E/A) were 53 (9.8%), 76 (14.1%), and 18 (3.4%), respectively. We used Delta(Ad<ARd+10) to confirm possible elevation of LV filling pressures in group 2. Compared with subjects with normal diastolic function (n=392, 72.7%), group 1 (209 versus 251 pmol/L; P=0.015) and group 2 (209 versus 275 pmol/L; P=0.0003) but not group 3 (209 versus 224 pmol/L; P=0.65) had a significantly higher adjusted NT-probrain natriuretic peptide. Higher age, body mass index, heart rate, systolic blood pressure, serum insulin, and creatinine were significantly associated with a higher risk of LV diastolic dysfunction. CONCLUSIONS: The overall prevalence of LV diastolic dysfunction in a random sample of a general population, as estimated from echocardiographic measurements, was as high as 27.3%

Influence of chorionicity on the heritability estimates of blood pressure: a study in twins

Influence of chorionicity on the heritability estimates of blood pressure: a study in twins. Fagard RH, Loos RJ, Beunen G, Derom C, Vlietinck R. Hypertension and Cardiovascular Rehabilitation Unit, Faculty of Medicine, University of Leuven, KU Leuven, Belgium. [email protected] BACKGROUND: A basic assumption of the twin design is that environmental influences including prenatal experiences are equal across twin types. However, the intra-uterine environment may differ according to the chorionicity of the monozygotic twins, which may have biased previous heritability estimates of blood pressure. OBJECTIVE: The aim of the present study was to assess whether the heritability of blood pressure, derived from measurements in monozygotic and dizygotic twins, differs according to the chorionicity of the monozygotic twins. METHODS: Conventional and 24-h ambulatory blood pressures were measured in 125 dizygotic twin pairs and in 97 dichorionic and 128 monochorionic monozygotic twin pairs at the age of 18-34 years. The twin sample was drawn from the East Flanders Prospective Twin Survey, in which perinatal data were collected at birth. Intra-pair correlation coefficients were calculated and compared between both types of monozygotic twin pairs. Heritability was estimated from model-fitting and path analysis, based on the dizygotic twins and, respectively, all monozygotic twins and the two subtypes. RESULTS: Intra-pair correlation coefficients for the various blood pressures, after adjustment for body mass index, ranged from 0.45 to 0.71 in the monozygotic twin pairs and did not differ significantly according to chorionicity. Heritability estimates of blood pressure were between 52 and 64%, and were similar when calculated from dizygotic twins and, respectively, dichorionic and monochorionic monozygotic twins. CONCLUSIONS: Heritability estimates of conventional and ambulatory blood pressure do not differ significantly according to the chorionicity of the monozygotic twins

Document de consensus. Du bon usage de l'automesure tensionnelle.

Self or home blood pressure measurement (HBPM) is increasingly popular. Its prognostic value and clinical interest in the diagnosis and follow-up of hypertension are well established. In addition, experts widely agree on the fact that it improves hypertension management and therapeutic compliance. In particular, HBPM often allows to detect white coat hypertension (to be confirmed by 24-hour ambulatory blood pressure measurement). Unfortunately, a large part of HBPM devices in the European Union have not fulfilled independent validation criteria. Furthermore, many patients buy and use such devices without medical supervision. This consensus document summarizes the advantages and disadvantages of HBPM and the conditions of a proper use, in agreement with the recent European and American guidelines

Influence of the endothelial nitric oxide synthase gene on conventional and ambulatory blood pressure: sib-pair analysis and haplotype study

Influence of the endothelial nitric oxide synthase gene on conventional and ambulatory blood pressure: sib-pair analysis and haplotype study. Persu A, Vinck WJ, Khattabi OE, Janssen RG, Paulussen AD, Devuyst O, Vlietinck R, Fagard RH. aNephrology Unit, Universite Catholique de Louvain, Brussels bHypertension and Cardiovascular Rehabilitation Unit, Katholieke Universiteit Leuven cCentre for Human Genetics, Katholieke Universiteit Leuven, Leuven, Belgium dCluster of Genetics and Cell Biology, Department of Population Genetics, Maastricht University, Maastricht eNutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht, The Netherlands. BACKGROUND: Nitric oxide is involved in the regulation of vascular basal tone and blood pressure. Polymorphisms of NOS3, the gene that codes for endothelial nitric oxide synthase, have been associated with essential hypertension. OBJECTIVE: To look for linkage and association of three di-allelic polymorphisms (Glu298Asp, intron 4 VNTR and T-786C) and the intron 13 CA-repeat of NOS3 with blood pressure as a continuous trait. METHODS: Genotyping was performed in 110 dizygotic white twin pairs from Flanders, Belgium. The influence of NOS3 polymorphisms on conventional and ambulatory blood pressure was assessed by sib-pair analysis and haplotype association analysis. RESULTS: Genotype frequencies were similar to those previously reported in white populations. Sib-pair analysis did not show a significant influence of either polymorphism on blood pressure. Haplotype analysis disclosed a significant association between NOS3 haplotypes and daytime ambulatory diastolic (P = 0.02) and systolic (P < 0.0001) blood pressure, the latter remaining significant after multiple testing was taken into account (P = 0.032). The association between daytime ambulatory systolic blood pressure and NOS3 haplotypes was mainly attributable to four haplotypes accounting for 11.9% of all represented haplotypes. CONCLUSION: We show for the first time a highly significant association of ambulatory blood pressure with NOS3 haplotypes in well-characterized white individuals from Flanders. These results pave the way for studies looking for the influence of NOS3 on blood pressure in high-risk subsets such as diabetic or hypertensive patients. They indicate the importance of ambulatory blood pressure and haplotype analysis in revealing the moderate effect of polymorphisms on blood pressur