The Role of Pharmaceutical Innovation in Clinical Practice Guidelines for Chronic Diseases.

Background: Over the last 25 years, clinical practice guidelines have emerged as a means to standardize and improve care. As pharmaceutical innovations develop, guidelines are updated to incorporate new interventions. However, the extent to which pharmacotherapies are represented as treatment options in guideline recommendations has not been well elucidated.

Role of Vascular Adaptation in Determining Systolic Blood Pressure in Young Adults.

Background Two individuals can have a similar pulse pressure (PP) but different levels of systolic blood pressure (SBP), although the underlying mechanisms have not been described. We hypothesized that, for a given level of PP, differences in SBP relate to peripheral vascular resistance (PVR); and we tested this hypothesis in a large cohort of healthy young adults. Methods and Results Demographic, biochemical, and hemodynamic data from 3103 subjects were available for the current analyses.

Stiffening and ventricular-arterial interaction in the ascending aorta using MRI: ageing effects in healthy humans.

Objectives: The aim of this study was to investigate the effect of age and sex on nPWV and ndI in the ascending aorta of healthy humans.

Background: Local pulse wave velocity (nPWV) and wave intensity (ndI) in the human ascending aorta have not been studied adequately, because of the need for invasive pressure measurements. However, a recently developed technique made the noninvasive determination of nPWV and ndI possible using measurements of flow velocity and arterial diameter.

Influence of the central-to-peripheral arterial stiffness gradient on the timing and amplitude of wave reflections.

In individuals with compliant aortas, peripheral muscular artery stiffness exceeds central elastic artery stiffness. With aging, central stiffness increases with little change in peripheral stiffness, resulting in a reversal of the normal stiffness gradient. This reversal may reduce the wave reflection amplitude due to the movement of the major 'effective' reflection site further from the heart.

Estimation of aortic pulse pressure using Fourier velocity encoded M-mode MR.

Purpose: To use a simplified hemodynamic model and Fourier-encoded velocity data to measure pulse pressure (PP) in the descending aorta.

Materials And Methods: A one-dimensional, cylindrically localized pulse sequence with Fourier velocity encoding (FVE) was used to obtain time-dependent velocity distributions along the descending aorta. Numerical evaluation of a simplified hemodynamic model, based on a cross-sectionally averaged form of the mass conservation equation, allowed estimation of the average pressure waveform and PP along 6-cm-long segments located within the descending aorta.

Evaluation of the Vicorder, a novel cuff-based device for the noninvasive estimation of central blood pressure.

Objectives: The Vicorder is a new brachial cuff-based device that estimates central blood pressure (cBP) using a brachial-to-aortic transfer function. The aim of this study was to evaluate cBP estimated by the Vicorder.

Methods: During cardiac angiography, cBP estimated by the Vicorder and the SphygmoCor was evaluated against simultaneous invasive cBP in 50 patients.

Use of the oral contraceptive pill is associated with increased large artery stiffness in young women: the ENIGMA study.

Background: The oral contraceptive pill (OCP) is widely prescribed throughout the world. Although it is associated with a small but significant increase in blood pressure, the influence of the OCP on large artery stiffness and wave reflection is unclear. The aim of this study was to determine the relationship between use of the OCP and aortic stiffness and wave reflections in a young, healthy cohort of women.

The relationship of age with regional aortic stiffness and diameter.

Objectives: The purpose of this study was to determine the impact of age on regional aortic pulse wave velocity (aPWV).

Background: aPWV is an independent predictor of cardiovascular risk and increases exponentially with age. However, it is unclear whether such changes occur uniformly along the length of the aorta or vary by region.

Using magnetic resonance imaging measurements for the determination of local wave speed and arrival time of reflected waves in human ascending aorta.

Wave speed is one of the key factors describing wave propagation in arteries [1]. Local wave speed is directly related to the arterial wall properties [2]. With aging, arterial wave speed increases due to the stiffening of arterial wall, and also related to arterial disease.

Age-related changes of regional pulse wave velocity in the descending aorta using Fourier velocity encoded M-mode.

Aortic pulse wave velocity (PWV) is an independent determinant of cardiovascular risk. Although aortic stiffening with age is well documented, the interaction between aging and regional aortic PWV is still a debated question. We measured global and regional PWV in the descending aorta of 56 healthy subjects aged 25-76 years using a one-dimensional, interleaved, Fourier velocity encoded pulse sequence with cylindrical excitation.

The impact of cardiovascular risk factors on aortic stiffness and wave reflections depends on age: the Anglo-Cardiff Collaborative Trial (ACCT III).

Ageing exerts differential effects on arterial stiffness and wave reflections. However, the impact of cardiovascular risk factors on arterial stiffness and wave reflections and, particularly, how such effects are influenced by ageing has not been assessed within a single large population, covering a sufficiently wide age range. Therefore, we determined the extent to which age alters the impact of traditional cardiovascular risk factors on arterial stiffness and wave reflections.

Validity and repeatability of the Vicorder apparatus: a comparison with the SphygmoCor device.

Aortic stiffness, an independent predictor of cardiovascular risk and all-cause mortality, can be estimated non-invasively by measuring carotid to femoral (aortic) pulse wave velocity (aPWV). The Vicorder device has been developed to measure aPWV with little operator training in a non-intrusive manner. The aim of this study was to assess the repeatability of aPWV measured with the Vicorder device and to compare aPWV values with those obtained using the SphygmoCor system.

The accuracy of central SBP determined from the second systolic peak of the peripheral pressure waveform.

Background: Recent evidence suggests that central aortic blood pressure may be a better predictor of cardiovascular risk than peripheral blood pressure. The central SBP (cSBP) can be estimated from the late systolic shoulder of the radial pulse waveform. We compared the second systolic peak of the radial waveform (pSBP(2)) with the central systolic pressure derived by a generalized transfer function in a large cohort, across a wide age range, of patients from the Anglo-Cardiff Collaborative Trial.

Aortic calcification is associated with aortic stiffness and isolated systolic hypertension in healthy individuals.

Arterial stiffening is an independent predictor of mortality and underlies the development of isolated systolic hypertension (ISH). A number of factors regulate stiffness, but arterial calcification is also likely to be important. We tested the hypotheses that aortic calcification is associated with aortic stiffness in healthy individuals and that patients with ISH exhibit exaggerated aortic calcification compared with controls.