Search PubMed⌕ Search

Biomedical subjects

Marcin Cwynar

Publications and source records attributed to Marcin Cwynar.

11 recordsLinked to original sources

Arterial characteristics in normotensive offspring of parents with or without a history of hypertension.

BACKGROUND: In this study we compared the arterial characteristics and blood pressure (BP) of normotensive offspring of two normotensive parents (OFF/NT) and normotensive offspring who had at least one hypertensive parent (OFF/HT). METHODS: A total of 174 OFF/HT (17 to 40 years of age) and 59 OFF/NT (16 to 34 years) were recruited in Cracow, Poland (n = 138) and Pilsen, Czech Republic (n = 95). Peripheral pulse pressure (PPp) was determined from conventional and 24-h ambulatory BP. A SphygmoCor device was used to measure the central (CAIx) and peripheral (PAIx) systolic augmentation indexes, central pulse pressure (PPc), and the aortic pulse wave velocity (PWV). In multivariate analyses family clusters and significant covariates were accounted for. RESULTS: The OFF/HT had higher (.14 < P < .0007) conventional BP and PPp on conventional BP measurement (121/75 v 114/71 mm Hg and 46 v 42 mm Hg) as well as on 24-h ambulatory monitoring (118/70 v 114/67 mm Hg and 48 v 47 mm Hg). OFF/HT, compared with OFF/NT, also had higher (.05 < P < .0008) PPc (28 v 26 mm Hg), PAIx (54.7% v 44.9%), CAIx (108.8% v 99.8%), and PWV (7.4 v 6.6 m/sec). However, complex adjustment including mean arterial pressure and age removed the differences between the offspring in the PAIx, CAIx, and PWV. CONCLUSIONS: Large-artery properties are altered in OFF/HT compared with OFF/NT. The findings from this cross-sectional study suggest that the alterations in arterial function in subjects with a family history of hypertension are determined mainly by an increased BP and age-related hemodynamic changes.

Adolescent↗

Sodium excretion as a modulator of genetic associations with cardiovascular phenotypes in the European Project on Genes in Hypertension.

Hypertension is a chronic age-related disorder, affecting nearly 20% of all adult Europeans. This disease entails debilitating cardiovascular complications and is the leading cause for drug prescriptions in Europeans older than 50 years. Intensive research over the past two decades has so far failed to identify common genetic polymorphisms with a major impact on blood pressure or associated cardiovascular phenotypes, suggesting that multiple genes each with a minor impact, along with gene-gene and gene-environment interactions, play a role. The European Project on Genes in Hypertension (EPOGH) is a large-scale, family-based study in which participants from seven different populations were phenotyped and genotyped according to standardized procedures. This review article summarizes the initial 5-year findings and puts these observations into perspective against other published studies. The EPOGH demonstrated that phenotype-genotype relations strongly depend on host factors such as gender and lifestyle, in particular salt intake as reflected by the 24-h urinary excretion of sodium. The EPOGH therefore highlights the concept that phenotype-genotype relations can only be studied within a defined ecogenetic context.

Blood Pressure↗

Reference values in white Europeans for the arterial pulse wave recorded by means of the SphygmoCor device.

Measurement of blood pressure together with applanation tonometry at the radial artery allows the reproducible assessment of various indexes of arterial stiffness, including the peripheral (PPp) and central pulse pressures (PPc) and the peripheral (Alp) and central augmentation indexes (Alc). We defined preliminary diagnostic thresholds, using the distributional characteristics of these hemodynamic measurements in a reference population. We randomly recruited 870 subjects from 3 European populations. PPp was the average difference between systolic and diastolic blood pressure measured five times at one home visit. For measurement of PPc, Alp and Alc, we used the SphygmoCor device. We selected subjects without hypertension, diabetes, dyslipidemia in need of medical treatment or previous or concomitant cardiovascular disease. The study population included 228 men and 306 women (mean age 34.9 years). All hemodynamic measurements were curvilinearly related to age, and Alp and Alc were lower in men than in women. In men at age 40, the upper 95% prediction bands of the relations of the hemodynamic measurements with age approximated 60 mmHg for PPp, 40 mmHg for PPc, 90% for Alp, and 30% for Alc. For PPc, Alp and Alc, these thresholds must be adjusted for age, leading to lower and higher thresholds at younger and older age, respectively. In addition, in women of any age, the Alp and Alc thresholds must be increased by 10% and 7%, respectively. Pending validation in prospective outcome studies, distributional characteristics of arterial stiffness indexes in a reference population can be used to generate operational thresholds for use in clinical practice.

Adolescent↗

Pulse wave velocity in patients with coronary artery disease or type 2 diabetes mellitus.

OBJECTIVE: To check whether the presence of coronary artery disease (CAD) or type 2 diabetes mellitus (DM) has a differentiating effect on arterial stiffness assessed with pulse wave velocity (PWV)--a simple, reproducible and clinically feasible measure of arterial stiffening. METHODS AND RESULTS: The mean age of 101 participants was 63.5 +/- 19.7 years. Fifty-one % of them had CAD, 31.0% had DM and 52.5% were hypertensive subjects. The aortic PWV ranged from 3.40 to 27.50 m/s, with an average of 1.73 +/- 4.69 m/s. PWV was significantly higher (P < 0.01) in both CAD and DM positive groups as compared with CAD and DM negatives, respectively. After adjustment for established co-variables, patients with CAD had significantly higher PWV when compared to CAD negatives (13.0 vs. 10.5 m/s, P < 0.01). After adjustment, DM did not seem to affect PWV. CONCLUSIONS: CAD patients had higher values of PWV when compared to those without the disease. DM, a metabolic equivalent of arterial damage, after adjustment for possible confounders, did not seem to contribute per se to arterial stiffening. The presence of high PWV values in that group of patients should be viewed as an indicator of established widespread atherosclerosis possibly affecting the coronary arteries.

Adult↗

Patient's education in arterial hypertension.

Non-compliance is an important factor in lack of appropriate control of blood pressure. Education of hypertensive patients on about consequences of hypertension and benefits of antihypertensive therapy has been reported to improve the results of the management of hypertension. The aim of this article is to present main factors influencing patients' compliance with antihypertensive treatment and the role of educational interventions in the process of therapy.

Antihypertensive Agents↗

Epistatic interaction between alpha- and gamma-adducin influences peripheral and central pulse pressures in white Europeans.

BACKGROUND: Adducin is a membrane skeleton protein consisting of alpha- and beta- or alpha- and gamma-subunits. Mutations in alpha- and beta-adducin are associated with hypertension. In the European Project on Genes in Hypertension, we investigated whether polymorphisms in the genes encoding alpha-adducin (Gly460Trp), beta-adducin (C1797T) and gamma-adducin (A386G), alone or in combination, affected pulse pressure (PP), an index of vascular stiffness. METHODS: We measured peripheral and central PP by conventional sphygmomanometry and applanation tonometry, respectively. We randomly recruited 642 subjects (162 nuclear families and 70 unrelated individuals) from three European populations. In multivariate analyses, we used generalized estimating equations and the quantitative transmission disequilibrium test. RESULTS: Peripheral and central PP averaged 46.1 and 32.6 mmHg, respectively. Among carriers of the alpha-adducin Trp allele, peripheral and central PP were 5.8 and 4.7 mmHg higher in gamma-adducin GG homozygotes than in their AA counterparts, due to an increase in systolic pressure. gamma-Adducin GG homozygosity was associated with lower urinary Na/K ratio among alpha-adducin Trp allele carriers and with higher urinary aldosterone excretion among alpha-adducin GlyGly homozygotes. Sensitivity analyses in founders and offspring separately, and tests based on the transmission of the gamma-adducin G allele across families, confirmed the interaction between the alpha- and gamma-adducin genes. CONCLUSIONS: In alpha-adducin Trp allele carriers, peripheral and central PP increased with the gamma-adducin G allele. This epistatic interaction is physiologically consistent with the heterodimeric structure of the protein and its influence on transmembranous sodium transport.

Adult↗

Association of peripheral and central arterial wave reflections with the CYP11B2 -344C allele and sodium excretion.

OBJECTIVE: Angiotensin II and aldosterone, generated by the angiotensin-converting enzyme (ACE) and aldosterone synthase (CYP11B2), respectively, not only regulate sodium and water homeostasis, but also influence vascular remodeling in response to high blood pressure. In the European Project on Genes in Hypertension (EPOGH), we therefore investigated whether the ACE I/D and CYP11B2 C-344T polymorphisms influence early arterial wave reflections, a measure of vascular stiffness. METHODS: We measured the peripheral and central augmentation index of systolic blood pressure by applanation tonometry at the level of the radial artery in 622 subjects (160 families and 64 unrelated individuals) randomly recruited from three European populations, whose average urinary sodium excretion ranged from 196 to 245 mmol/day. In multivariate analyses, with sodium excretion analyzed as a continuous variable, we explored the phenotype-genotype associations by means of generalized estimating equations and the quantitative transmission disequilibrium test. RESULTS: The peripheral and central augmentation indexes were significantly higher in CYP11B2 -344C allele carriers than in -344T homozygotes. In offspring, early wave reflections increased with the transmission of the -344C allele. This effect of the CYP11B2 polymorphism occurred in subjects with a higher than median urinary sodium excretion (210 mmol/day). The ACE I/D polymorphism did not influence augmentation of systolic blood pressure. CONCLUSIONS: The CYP11B2 C-344T polymorphism affects arterial stiffness. However, sodium intake seems to modulate this genetic effect.

Adult↗

[Laser doppler flowmetry--repeatability of the method].

The aim of the study was to evaluate the repeatability of flow microcirculation measurements by laser doppler flowmetry (Periflix, firm Perimed, Sweden). Measurements of right forearm skin perfusion were performed twice in 3-4 day intervals in 40 healthy subject aged 39.5 +/- 18.3. Two independent investigators analysed the results. Pearson correlation and analysis ac. Bland and Altman (Lancet 1986, 1, 307-310) were performed during comparing results obtained in the same studied persons and by the investigators. There was a high correlation between the compared results performed on the same subjects within a few days interval, especially between the results for post-occlusive congestion reaction in basic temperature (r = 0.64-0.72) and the results for congestion reaction at a temperature of 44 degrees C (r = 0.5-0.56). High correlation values (r = 0.8-0.95) were also observed when comparing both investigators' evaluations. Repeatability evaluation using Bland and Altman analysis was poorer, especially for values observed in resting conditions and for some values observed after stimulation with both investigators (2.5-10% of results were out of interval: mean +/- 2SD). The results show good repeatability of microcirculation flow measurements, especially under stimulation.

Adult↗

[Mechanisms of large artery remodeling].

Degenerative changes of elastin, increase of collagen fibres, proliferation of muscle cells and impairment in endothelium function occurs in the vessel wall with ageing, in hypertensive and others diseases. Early changes are potentially reversible. Atherosclerosis is a late stage of pathologies occurring in the arterial wall in response to various factors. The present paper describes current knowledge on mechanisms of arterial wall remodelling. The authors define basic indices of arterial compliance and describe several physiological and pathological factors which occur play the main role in process of arterial wall remodelling. A chapter is devoted to the effects of increased arterial stiffness on heart pathology and clinical implications of measuring these parameters.

Age Factors↗

[Pulse wave analysis: from the basic sciences to clinical applications].

Assessment of the pulse character is one of the earliest recorded medical skills, but objective recordings of pulse waveform emerged only in the nineteenth century. This technique fell into disuse with the advent of the sphygmomanometer, but interest has recently been rekindled with the introduction of computer technology and high fidelity applanation tonometry. Sphygmocardiography is a non-invasive and accurate technology which utilizes tonometric analysis of the radial or carotid artery pulse wave and measurement of peripheral arterial blood pressure to derive a central arterial pulse wave, central arterial blood pressure and related indices. In clinical studies pulse wave analysis is a highly reproducible method and easy to apply. This measure provides important information about arterial stiffness and heart-vascular interactions. This technique may provides better cardiovascular risk assessment associated with increased arterial stiffness and allow treatment to be targeted to those most in need.

Blood Pressure↗