Giacomo Pucci

Metabolic Syndrome Is Associated With Aortic Stiffness in Untreated Essential Hypertension

Metabolic syndrome is a powerful predictor of cardiovascular disease in hypertension, and large-artery stiffness is increasingly recognized as a cardiovascular risk factor. We hypothesized that the adverse prognostic significance of the metabolic syndrome in hypertension might be explained in part by its association with aortic stiffness. A total of 169 newly diagnosed, never treated, nondiabetic patients with essential hypertension (men 55%, 48±11 years) were classified by the presence (n=45) or absence (n=124) of the metabolic syndrome. All patients underwent aortic and upper limb pulse wave velocity determination by means of an applanation tonometry-based method. Aortic pulse wave velocity had a direct correlation with office and 24-hour systolic pressure (r=0.42 and 0.31, respectively), as well as with waist circumference (r=0.35, all P<0.001), but not with body mass index (r=0.10, P=not significant). Aortic pulse wave velocity was higher in the subgroup with the metabolic syndrome (10.0±2.7 versus 8.8±2.1 m/s; P=0.003), whereas upper limb velocity did not differ in the 2 groups (8.6±1.4 versus 8.7±1.5 m/s; P=not significant). In a multiple regression, aortic pulse wave velocity was independently associated with age, systolic blood pressure, and the metabolic syndrome. Only diastolic BP independently predicted upper limb pulse wave velocity. We conclude that in untreated hypertension, the metabolic syndrome is independently associated with a higher aortic, but not upper limb, pulse wave velocity. Central, but not general, adiposity is an important determinant of aortic stiffness in hypertension.

Relationship Between Short-Term Blood Pressure Variability and Large-Artery Stiffness in Human Hypertension: Findings From 2 Large Databases

Short-term blood pressure (BP) variability predicts cardiovascular complications in hypertension, but its association with large-artery stiffness is poorly understood and confounded by methodologic issues related to the assessment of BP variations over 24 hours. Carotid-femoral pulse wave velocity (cfPWV) and 24-hour ambulatory BP were measured in 911 untreated, nondiabetic patients with uncomplicated hypertension (learning population) and in 2089 mostly treated hypertensive patients (83% treated, 25% diabetics; test population). Short-term systolic BP (SBP) variability was calculated as the following: (1) SD of 24-hour, daytime, or nighttime SBP; (2) weighted SD of 24-hour SBP; and (3) average real variability (ARV), that is, the average of the absolute differences between consecutive SBP measurements over 24 hours. In the learning population, all of the measures of SBP variability showed a direct correlation with cfPWV (SD of 24-hour, daytime, and nighttime SBP, r=0.17/0.19/0.13; weighted SD of 24-hour SBP, r=0.21; ARV, r=0.26; all P<0.001). The relationship between cfPWV and ARV was stronger than that with 24-hour, daytime, or nighttime SBP (all P<0.05) and similar to that with weighted SD of 24-hour SBP. In the test population, ARV and weighted SD of 24-hour SBP had stronger relationships with cfPWV than SD of 24-hour, daytime, or nighttime SBP. In both populations, SBP variability indices independently predicted cfPWV along with age, 24-hour SBP, and other factors. We conclude that short-term variability of 24-hour SBP shows an independent, although moderate, relation to aortic stiffness in hypertension. This relationship is stronger with measures of BP variability focusing on short-term changes, such as ARV and weighted 24-hour SD.

Ambulatory Arterial Stiffness Index Is Not a Specific Marker of Reduced Arterial Compliance

Ambulatory arterial stiffness index (AASI), a measure based on the relative behavior of 24-hour systolic and diastolic blood pressure (BP), has been suggested as a marker of arterial stiffness and a predictor of cardiovascular mortality. However, a narrow range of diastolic BP values over the 24 hours tends to flatten the regression slope and to artificially increase AASI. We explored the possible influence of different ranges of 24-hour diastolic BP fluctuations, such as those related to nocturnal BP fall, on AASI, and on its relationship with target organ damage. In 515 untreated hypertensive patients, AASI was directly related to age (r=0.30) and 24-hour systolic BP (r=0.20), whereas it was inversely related with nocturnal systolic and diastolic BP reduction (r=−0.28 and −0.46, respectively; all P<0.001). A direct relationship was found between AASI and left ventricular mass index (r=0.17; P<0.001), but this relation was no longer significant after adjustment for age, sex, body mass index, daytime systolic BP, and day-night systolic BP reduction (all P<0.05). AASI was directly related to carotid-femoral pulse wave velocity, an intrinsic measure of aortic stiffness (r=0.28; P<0.001), but no independent relation was found in a multiple linear regression. Our conclusions are as follows: (1) AASI is strongly dependent on the degree of nocturnal BP fall in hypertensive patients; (2) there is no significant relation between AASI and left ventricular mass after proper adjustment for confounders; and (3) the relation between AASI and a widely accepted measure of aortic stiffness, such as pulse wave velocity, is weak and importantly affected by other factors.

Different Impact of the Metabolic Syndrome on Left Ventricular Structure and Function in Hypertensive Men and Women

Metabolic syndrome (MS) is increasingly recognized as an important cardiovascular risk factor in hypertension, but its influence on left ventricular (LV) mass and function in the 2 genders has not been specifically addressed. Among 618 nondiabetic, untreated hypertensive subjects, echocardiographically detected LV mass was significantly greater in subjects with MS. A significant interaction was observed between sex and the MS (P<0.003 for the multiplicative interaction term). Compared with women without the MS, those with the syndrome had a 24% greater LV mass (49.5±12 versus 40.0±10 g×m−2.7; P<0.001), whereas the difference was only 9% in men (50.3±12 versus 46.1±10 g×m−2.7; P=0.003). A greater prevalence of LV hypertrophy was found in women (37% versus 14%; P<0.001) but not in men (39% versus 29%; P=0.09) with the MS. After adjustment for the effect of age, body mass index, 24-hour systolic blood pressure, and several confounders, the MS was independently associated with a greater LV mass index in women (regression coefficient, 4.80; P<0.001) but not in men. Women with the MS also had a greater LV relative wall thickness (0.42±0.07 versus 0.39±0.07; P=0.004) and a depressed afterload-corrected midwall fractional shortening (94.0±12% versus 101.0±13%; P<0.001) than women without the syndrome, whereas no differences emerged in men. We conclude that, in untreated hypertension, MS has a different impact on LV hypertrophy and function in men and women. The effect of MS is more pronounced in women and is partly independent from the effect of several hemodynamic and nonhemodynamic determinants of LV mass.

Aortic Stiffness in Untreated Adult Patients With Human Immunodeficiency Virus Infection

HIV infection is associated with chronic immune activation, subclinical inflammation, and an atherogenic metabolic profile. It remains controversial whether HIV infection is a risk factor for accelerated arteriosclerosis independent from the effects of antiretroviral drugs. We investigated whether aortic stiffness, an early marker of arteriosclerosis, is increased in HIV patients who were not under antiretroviral treatment. In 39 untreated HIV-infected patients and 78 individually matched age-, sex-, and blood pressure–matched HIV-uninfected control subjects, we determined aortic pulse wave velocity (PWV), a direct noninvasive measure of aortic stiffness, by tonometric method. Subjects with overt cardiovascular disease or major cardiovascular risk factors were excluded from the study. Prevalence of the metabolic syndrome was higher in HIV patients (18% versus 5%; P=0.025). HIV patients had a higher aortic PWV (7.5±1.4 versus 6.7±1.1 m · s−1; P=0.001) than control subjects. Age, mean arterial pressure as a measure of distending pressure, and HIV infection (all P<0.05) independently predicted aortic PWV when a consistent number of cardiovascular risk factors was simultaneously controlled for. Among HIV-infected subjects, serum γ-glutamyl transpeptidase concentration (β=0.46; P=0.003) and mean arterial pressure (β=0.32; P=0.03) were independent determinants of aortic PWV. In conclusion, aortic stiffness is increased in HIV-infected individuals who have never received antiretroviral therapy. PWV increases with increasing serum γ-glutamyl transpeptidase concentration. Our data support the hypothesis that HIV infection is a risk factor for arteriosclerosis.

Relation between renal function within the normal range and central and peripheral arterial stiffness in hypertension.

Chronic kidney disease is accompanied by increased large-artery stiffness, but the relation between glomerular filtration rate within the reference range and central or peripheral arterial stiffness has been understudied. The link between renal function and arterial stiffness was assessed in 305 patients with never-treated essential hypertension (men: 58%; age: 48±11 years, blood pressure: 151/95±20/11 mm Hg), free from overt cardiovascular disease and with serum creatinine values <1.4 mg/dL (men) and <1.2 mg/dL (women), who underwent noninvasive aortic and upper-limb pulse wave velocity (PWV) determination. Aortic PWV was strongly related to age (r=0.55; P<0.001), whereas upper-limb PWV had a weaker nonlinear relation with age (&bgr;=1.392; P<0.001 for age; &bgr;=−1.312; P<0.001 for age squared) and a weak relation with aortic PWV (r=0.22; P<0.001). Glomerular filtration rate (GFR), estimated according to the Mayo clinic equation for healthy subjects, was inversely correlated with large-artery stiffness, as assessed by aortic PWV (r=−0.34; P<0.001), and with peripheral artery stiffness, as assessed by upper-limb PWV (r=−0.25; P<0.001). In a multivariate linear regression, aortic PWV was independently predicted by age (&bgr;=0.48; P<0.001), mean arterial pressure (&bgr;=0.14; P=0.013), and GFR (&bgr;=−0.13, P=0.029). Upper-limb PWV was predicted by GFR (&bgr;=−0.24; P<0.001) and mean arterial pressure (&bgr;=0.20; P<0.001). We conclude that, in hypertensive patients with normal renal function, an inverse relationship exists between GFR and stiffness of both central elastic and peripheral muscular arteries. These relations are in part independent from the effect of several confounders, including age, sex, and blood pressure values.

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. The two devices were also compared noninvasively in a separate group of 90 healthy individuals. Results: Central SBP (cSBP) obtained with each device satisfied the American Association for the Advancement of Medical Instrumentation accuracy criteria when peripheral waveforms were calibrated to invasive mean arterial pressure (MAP)/DBP: estimated − invasive cSBP difference, −4.0 ± 7.4 mmHg, Vicorder, P < 0.001; −1.4 ± 7.9 mmHg, SphygmoCor, P = 0.21. When oscillometric brachial SBP/DBP was used for peripheral waveform calibration, cSBP was underestimated by Vicorder (&Dgr; −6.4 ± 7.4 mmHg, P < 0.001 versus invasive) and more so by SphygmoCor (&Dgr; −11.9 ± 7.2 mmHg, P < 0.001 versus invasive). Conversely, cSBP was more closely estimated by SphygmoCor when waveforms were calibrated to brachial MAP/DBP (&Dgr; −2.8 ± 9.4 mmHg, P = 0.04 versus invasive). In the noninvasive study, Vicorder cSBP correlated well with SphygmoCor cSBP when SphygmoCor waveforms were calibrated to brachial MAP/DBP (121 ± 16 versus 121 ± 17 mmHg, P = 0.2) but not when brachial SBP/DBP was used for calibration (115 ± 19 mmHg, P < 0.001). Conclusion: The Vicorder and SphygmoCor devices provide reliable estimates of cSBP when calibrated to invasive pressure. When calibrated to brachial BP, both devices underestimated cSBP, although this was attenuated when SphygmoCor was calibrated to brachial MAP/DBP. Vicorder may be a simple alternative to tonometry-based methods for noninvasive assessment of cBP.

Age-Specific Relationship of Aortic Pulse Wave Velocity With Left Ventricular Geometry and Function in Hypertension

Aortic pulse wave velocity (PWV), generally considered an intrinsic marker of arterial stiffness, might depend in part on the velocity of myocardial fiber shortening, but the relation between PWV and myocardial function in humans has been understudied. A total of 237 untreated hypertensive subjects over a wide age range (18 to 88 years) underwent aortic PWV determination and echocardiography, from which the mean velocity of circumferential fiber shortening was calculated as a measure of the velocity of myocardial shortening, and relative wall thickness was taken as a measure of left ventricular concentric remodeling. Patients were divided in 3 age groups (<40 years, 40 to 59 years, and ≥60 years). In the young, aortic PWV was directly associated with heart rate–corrected velocity of circumferential fiber shortening (r=0.39; P=0.002) but not to relative wall thickness (r=−0.01; P=0.95). The opposite was found in the older group, in which aortic PWV was accompanied by a concentric left ventricular geometric pattern (r=0.44 with relative wall thickness; P=0.009) and a reduced velocity of circumferential fiber shortening (r=−0.54; P<0.001) and stress-corrected midwall fractional shortening (r=−0.56; P<0.001). Intermediate values were found in the middle-aged group (r=0.23; P<0.01 with relative wall thickness; r=−0.07, P value not significant with velocity of circumferential fiber shortening). In conclusion, the relation between aortic PVW and the left ventricle is strongly age dependent. These data suggest that, in young people, aortic PWV is partly determined by an increased velocity of myocardial shortening. With increasing age, a relationship between aortic PWV (as a measure of arterial stiffness) and left ventricular concentric geometry emerges, which ultimately leads to a depressed ventricular systolic function.

Large-artery stiffness: A reversible marker of cardiovascular risk in primary hyperparathyroidism

OBJECTIVE Patients with primary hyperparathyroidism (pHPT) are at increased risk of cardiovascular mortality. We investigated whether aortic stiffness, an early marker of arteriosclerosis and a strong predictor of cardiovascular risk, is increased in pHPT, and whether it improves after parathyroidectomy. METHODS Twenty-four patients with mild pHPT (age 56 ± 10 years, blood pressure 136/85 mmHg, serum calcium 2.55-3.00 mmol/L) and 48 control subjects individually matched with cases by age, sex and blood pressure underwent aortic (carotid-femoral) and upper-limb (carotid-radial) pulse wave velocity (PWV) determination by applanation tonometry in a case-control study. Subjects with renal disease, diabetes, treated hypertension or overt cardiovascular disease were excluded from the study. Seventeen of the patients with pHPT were re-examined 4 weeks after surgical parathyroidectomy. RESULTS Aortic PWV was significantly higher among pHTP patients (11.4 ± 2 vs 9.6 ± 2 m/s, p<0.001). In a conditional logistic regression analysis, pHPT was independently associated with an increased risk of having an aortic PWV >12 m/s (odds ratio 3.28, 95% confidence interval 1.21-8.93). As expected, surgery was accompanied by a reduction in serum calcium (from 2.77 ± 0.2 to 2.25 ± 0.1 mmol/L, p<0.001) and parathyroid hormone (from 29.6 ± 10 to 3.3 ± 2 pmol/L, p<0.001). Aortic PWV decreased after surgery (from 10.9 ± 2 to 9.8 ± 2 m/s, p=0.003). The change in aortic PWV remained significant also after adjustment for changes in blood pressure (p<0.01). Changes in upper-limb PWV generally paralleled those in aortic PWV. CONCLUSION pHPT is associated with increased aortic stiffness, which improves after parathyroidectomy. Our data demonstrate that aortic stiffness may improve upon removal of hyperparathyroid stimuli.

Prevalence, Awareness, Treatment, and Control Rate of Hypertension in HIV-Infected Patients: The HIV-HY Study

BACKGROUND We aimed to assess the prevalence of hypertension in an unselected human immunodeficiency virus (HIV)-infected population and to identify factors associated with hypertension prevalence, treatment, and control. METHODS We used a multicenter, cross-sectional, nationwide study that sampled 1,182 unselected, consecutive, HIV-infected patients. Office blood pressure was accurately measured with standard procedures. RESULTS Patients were 71% men and 92% white, with a median age of 47 years (range = 18-78); 6% were antiretroviral treatment naive. The overall prevalence of hypertension was 29.3%; high-normal pressure accounted for an additional 12.3%. Among hypertensive subjects, 64.9% were aware of their hypertensive condition, 52.9% were treated, and 33.0% were controlled (blood pressure < 140/90 mm Hg). Blood pressure-lowering medications were used in monotherapy in 54.3% of the subjects. Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers were the most frequently used drugs (76.1%: monotherapy = 39.1%, combination treatment = 37.0%). In multivariable regression models, hypertension was independently predicted by traditional risk factors, including age ≥50 years, male sex, family history of cardiovascular disease, body mass index ≥25 kg/m2, previous cardiovascular events, diabetes, central obesity, and metabolic syndrome, as well as by duration of HIV infection, duration of antiretroviral therapy, and nadir CD4+ T-cell count <200/μl. The choice of protease inhibitors vs. nonnucleoside reverse transcriptase inhibitors as a third antiretroviral drug was irrelevant. CONCLUSIONS Hypertension affects nearly 30% of HIV adult outpatients in Italy. More than one-third of the hypertensive subjects are unaware of their condition, and more than two-thirds are uncontrolled. A higher level of attention to the diagnosis and treatment of hypertension is mandatory in this setting.