Prognostic impact of prolonged ventricular repolarization in hypertension.

BACKGROUND: QT interval prolongation on the surface electrocardiogram (ECG) predicts cardiovascular complications in high-risk subjects, but its prognostic role in uncomplicated hypertension has been understudied. METHODS: For up to 13 years (average, 5.3 years), we followed up 2110 white patients with initially untreated essential hypertension (mean +/- SD age, 49 +/- 12 years; 55% men) without prevalent cardiovascular or renal disease who underwent 12-lead ECG before therapy. We excluded patients with ECG abnormalities including ischemia, necrosis, complete bundle branch block, atrial fibrillation, arrhythmias, and ventricular preexcitation. RESULTS: Heart rate-corrected QT interval (QTc) showed a weak but significant direct association with systolic blood pressure (r = 0.07; P<.001), diastolic blood pressure (r = 0.11; P<.001), and Cornell voltage (r = 0.06; P = .006). During follow-up, 84 patients developed new-onset ischemic heart disease (0.75 event per 100 patient-years). After adjustment (Cox model) for the effects of age, sex, diabetes mellitus, serum cholesterol level, serum creatinine level, smoking, left ventricular hypertrophy, and 24-hour systolic blood pressure, patients with a prolonged QTc (>or=450 milliseconds in women and >or=440 milliseconds in men) had a nearly 2-fold increase in risks of coronary events (hazard ratio, 1.95; 95% confidence interval, 1.12-3.42; P = .02) and cardiovascular death (hazard ratio, 2.05; 95% confidence interval, 1.03-4.37; P = .04). Coronary heart disease risk was independently higher by 33% (95% confidence interval, +7% to +66%; P = .01) for each 32-millisecond increase in QTc. CONCLUSIONS: Prolonged ventricular repolarization is a risk factor for ischemic heart disease and cardiovascular mortality in subjects with uncomplicated hypertension. Its prognostic significance adds to that of several traditional cardiovascular risk factors, including left ventricular hypertrophy.

Prognostic value of the metabolic syndrome in essential hypertension.

OBJECTIVES: We sought to determine the prognostic significance of the metabolic syndrome in hypertension. BACKGROUND: Increased cardiovascular risk in hypertensive patients might be partially attributable to metabolic disturbances. METHODS: We prospectively followed for up to 10.5 years (mean 4.1 years) a total of 1742 hypertensive patients without cardiovascular disease (55% men; blood pressure [BP] 154/95 mm Hg; age 50 +/- 12 years). A modified National Cholesterol Education Program definition for metabolic syndrome was used, with body mass index in place of waist circumference. RESULTS: During follow-up, 162 patients developed cardiovascular events (2.28 events/100 patient-years). Event rates in the groups with one to five characteristics of the metabolic syndrome were 1.54, 1.96, 2.97, 3.35, and 5.27 per 100 patient-years, respectively (p < 0.001). A total of 593 patients (34%) had the metabolic syndrome. Patients with the syndrome had an almost double cardiovascular event rate than those without (3.23 vs. 1.76 per 100 patient-years, p < 0.001). After adjustment for age, gender, total cholesterol, creatinine, smoking, left ventricular hypertrophy, and 24-h systolic BP, the risk of developing cardiovascular events was still higher in patients with the metabolic syndrome (hazard ratio [HR] 1.73, 95% confidence interval [CI] 1.25 to 2.38). The syndrome was an independent predictor of both cardiac and cerebrovascular events (HRs 1.48 and 2.11, respectively). The adverse prognostic value of the metabolic syndrome was attenuated but still significant among the 1637 patients without diabetes (HR 1.43, 95% CI 1.02 to 2.08). CONCLUSIONS: In hypertensive subjects, the metabolic syndrome amplifies cardiovascular risk associated with high BP, independent of the effect of several traditional cardiovascular risk factors.

Prognostic significance of isolated, non-specific left ventricular repolarization abnormalities in hypertension.

OBJECTIVE: Clinicians are often confronted with the incidental finding of isolated minor, non-specific repolarization changes on the electrocardiogram (ECG) in hypertensive patients. The aim of this study was to investigate the prognostic significance of such changes. DESIGN: Prospective, observational study. METHODS: A total of 1970 hypertensive patients without prevalent cardiovascular disease were followed for up to 9.1 years (mean 4.7 years). Patients with ECG abnormalities including ischaemia, previous infarction, bundle branch block, atrial fibrillation and ventricular pre-excitation were excluded. Patients were divided into three groups: normal left ventricular (LV) repolarization (n = 1355); minor repolarization changes (n = 504); and typical LV strain (n = 111). RESULTS: During follow-up, 78 patients developed new-onset ischaemic heart disease. The event rates were 0.50, 1.28 and 3.08 per 100 patient-years in the groups with normal repolarization, minor changes, and typical LV strain, respectively (P < 0.001). After adjustment for the effect of age, sex, diabetes, serum cholesterol, smoking, LV hypertrophy and 24-h pulse pressure, the risk for developing coronary events was higher in patients with minor repolarization changes (hazard ratio 2.07, 95% confidence interval 1.23-3.47; P < 0.01) or LV strain (hazard ratio 4.00, 95% confidence interval 2.09-7.65; P < 0.001) than in patients with normal repolarization (reference category). Population-attributable risks were 21 and 14%, respectively. Minor ST-T changes also retained an adverse prognostic value among patients without LV hypertrophy (hazard ratio 1.90, 95% confidence interval 1.08-3.33; P = 0.026). CONCLUSION: We have identified minor, non-specific LV repolarization changes as a novel, independent risk factor for ischaemic heart disease in patients with uncomplicated hypertension.

Increased C-reactive protein concentrations in never-treated hypertension: the role of systolic and pulse pressures.

OBJECTIVE: To test whether the plasma concentration of C-reactive protein (CRP), a sensitive marker of systemic inflammation, is increased in patients with newly diagnosed, never-treated hypertension and whether blood pressure and its pulsatile component, pulse pressure, are correlated with plasma CRP concentration independently of a consistent number of cardiovascular risk factors. DESIGN: Cross-sectional study in a hospital outpatient hypertension clinic. METHODS: A total of 135 newly diagnosed, never-treated patients with hypertension and 40 healthy matched non-hypertensive controls underwent office and 24-h blood pressure measurement and blood sampling for determination of plasma CRP and serum lipid concentrations. RESULTS: Plasma CRP concentration was greater in hypertensive individuals (1.85 mg/l, interquartile range 0.74-3.64) than in control individuals (1.01 mg/l, interquartile range 0.67-1.88; P = 0.02). In the entire population, CRP had a significant direct association with office systolic blood pressure and pulse pressure, but not with diastolic blood pressure. Among hypertensive patients, plasma CRP was related to 24-h systolic blood pressure (r = 0.28, P < 0.01) and pulse pressure (r = 0.32, P < 0.01), but not to diastolic blood pressure (r = 0.12, P > 0.2). CRP was also directly associated with body mass index (r = 0.25, P < 0.01), serum low-density lipoprotein cholesterol (r = 0.21, P = 0.03) and serum triglycerides (r = 0.21, P = 0.03). In the multivariate analysis, systolic blood pressure and pulse pressure, but not diastolic blood pressure, were significant predictors of plasma CRP concentration when a consistent number of cardiovascular risk factors was controlled for simultaneously. CONCLUSIONS: Systolic blood pressure and pulse pressure, but not diastolic blood pressure, are predictors of plasma C-reactive protein concentrations in patients with newly diagnosed, never-treated hypertension, irrespective of the potential proinflammatory action of traditional cardiovascular risk factors.

Effect of body weight changes on 24-hour blood pressure and left ventricular mass in hypertension: a 4-year follow-up.

BACKGROUND: Few data are available on the long-term effects of weight loss on 24-h blood pressure (BP) and left ventricular mass in overweight hypertensive patients. METHODS: A total of 181 never-treated overweight hypertensive subjects (body mass index, 25 to 39 kg/m(2), office BP 145/94 +/- 12/7 mm Hg) had 24-h BP monitoring and echocardiography twice, at baseline and after 3.8 +/- 2 years (minimum 1 year). None of the subjects received antihypertensive drugs during the follow-up. Main outcome measures were changes in 24-h BP and in left ventricular mass. RESULTS: Percent change in body weight had a direct relationship with 24-h BP changes (r = 0.35 and 0.31 for systolic and diastolic BP, respectively; both P <.001). The associations with office BP changes (r = 0.13, P =.10 for systolic BP; r = 0.15, P =.06 for diastolic BP) were significantly weaker (both P <.01, z test). The patients who lost weight during follow-up (n = 106) had a significantly lower increase in 24-h BP (+0.6 +/- 9/ +0.2 +/- 6 v +4.9 +/- 9/ +2.7 +/- 7 mm Hg for systolic/diastolic BP, both P <.01) and in left ventricular mass (-3 +/- 30 g v +9 +/- 32 g, P <.02) than the remaining subjects. In a multiple linear regression, a 10% weight loss independently predicted a 4.3/3.8 mm Hg decrease in 24-h systolic/diastolic BP. CONCLUSIONS: Long-term weight loss determines a sustained BP reduction during the 24 h and a decrease in left ventricular mass in overweight hypertensive subjects. The relation of weight loss with ambulatory BP changes is closer than that with office BP.

Plasma C-reactive protein in subjects with hypo/hyperalphalipoproteinemias.

Hypoalphalipoproteinemia (Hypo-A), a lipid disorder characterized by low high-density lipoprotein (HDL)-cholesterol (HDL-C) levels, is frequently associated with an increased risk of suffering future coronary heart disease (CHD). Conversely, hyperalphalipoproteinemia (Hyper-A) is a characterized by high HDL-C concentrations and is possibly associated with longevity and protection against CHD. Whether plasma C-reactive protein (CRP) level, an emerging marker of CHD risk, may be influenced by either extremely low or high HDL-C concentrations is yet to be determined. Plasma levels of lipids and CRP have been measured in 52 middle-aged men and women, clinically free of CHD, including 20 subjects with Hypo-A, 12 with Hyper-A, and 20 healthy normolipemic age-matched controls. CRP levels were the highest in Hypo-A [0.22 mg/dL (interquartile range, 0.15 to 0.44)], the lowest in Hyper-A [0.03 mg/dL (0.02 to 0.07)], and intermediate in the control group [0.10 mg/dL (0.05 to 0.20)]. Differences in plasma CRP concentrations were significant between Hypo-A and the other 2 groups, as well as between Hyper-A and controls. Plasma CRP levels showed a particularly strong correlation with plasma HDL-C concentrations (r = -.66, P <.001). In multivariate models, HDL-C represented the only significant predictor of circulating levels of CRP. In conclusion, in subjects with Hypo-A or Hyper-A, HDL-C levels may account for plasma CRP variations independent of other potential cardiovascular risk factors.

Simvastatin increases bone mineral density in hypercholesterolemic postmenopausal women.

Statins are able to reduce cardiovascular morbility and mortality mainly through their hypocholesterolemic effect. Beyond the inhibition of cholesterol synthesis, the identification of "ancillary" mechanisms has motivated studies evaluating the relationship between the use of statins and the modification of bone mineral density (BMD). To date, clinical trials have provided discordant results. The aim of our study was to evaluate whether simvastatin treatment (40 mg/d) could modify BMD in hypercholesterolemic women (n = 40) after a 2-year treatment as compared with a control group treated only with diet (n = 20) and matched by gender, age, body mass index (BMI), lipids, menopausal age, and BMD and the number of osteopenic, osteoporotic, and normal women (on the basis of T-score value). Exclusion criteria were secondary hyperlipemias and osteoporosis and current or previous therapy with statins, bisphosphonates, and estrogens. The BMD was measured at the lumbar spine and hip by dual energy x-ray absorpiometry (DEXA). In the group treated by simvastatin, BMD, both on the spine and femoral hip, showed a significant increase after 8 and 24 months, respectively (0.878 +/- 0.133 v 0.893 +/- 0.130 and 0.907 +/- 0.132; 0.840 +/- 0.101 v 0.854 +/- 0.101; and 0.863 +/- 0.10, P <.001); there was a percentage increase of 1.7% after 8 months and 3.3% after 24 months at the spine; at the femoral hip, BMD increased 1.6% after 8 months and 2.7% after 24 months. The group treated only with hypolipidic diet demonstrated after 8 and 24 months a slight decrease in BMD both on the spine and femoral hip (respectively, 0.884 +/- 0.175 v 0.872 +/- 0.174 and 0.861 +/- 0.164; 0.860 +/- 0.110 v 0.853 +/- 0.096 and 0.847 +/- 0.095; P <.05). In conclusion, as partly suggested by retrospective or observational data, this longitudinal study indicates that simvastatin treatment exerts a beneficial effect on BMD.

Artichoke juice improves endothelial function in hyperlipemia.

Artichoke extracts have been shown to produce various pharmacological effects, such as the inhibition of cholesterol biosynthesis and of LDL oxidation. Endothelial dysfunction represents the first stage of atherosclerotic disease; it is usually evaluated in humans by a noninvasive ultrasound method as brachial flow-mediated vasodilation (FMV) and by the determination of several humoral markers such as vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and E-selectin. Aim of the study was to investigate the effects of dietary supplementation with artichoke juice on brachial FMV of hyperlipemics. We studied 18 moderately hyperlipemic patients (LDL cholesterol > 130 <200 mg/dl and/or triglycerides >150 <250 mg/dl) of both genders and 10 hyperlipemic patients, matched for age, sex and lipid parameters. All subjects were under isocaloric hypolipidic diet. A basal determination of serum lipids, soluble VCAM-1, ICAM-1, E-selectin and brachial FMV was performed. Thereafter patients were given 20 ml/die of frozen artichoke juice. The same parameters were repeated after 6 weeks. After artichoke treatment there was an increase of triglycerides (156 +/- 54 vs 165 +/- 76 mg/dL, p <0.05) and a reduction of total cholesterol (261 +/- 37 vs 244 +/- 38 mg/dL, p <0.05) and LDL cholesterol (174 +/- 31 vs 160 +/- 34 mg/dL, p <0.05). Controls showed a significant decrease in total and LDL cholesterol (respectively: 267 +/- 22 vs 249 +/- 20 mg/dL and 180 +/- 24 vs 164 +/- 23 mg/dL, both p <0.001). After artichoke there was a decrease in VCAM-1(1633 +/- 1293 vs 1139 +/- 883 ng/mL, p <0.05) and ICAM-1(477 +/- 123 vs 397 +/- 102 ng/mL, p <0.05), brachial FMV increased (3.3 +/- 2.7 vs 4.5 +/- 2.4%, p <0.01), while controls did not exhibit significant changes in VCAM-1, ICAM-1, E-selectin and brachial FMV. Univariate analysis showed that, in artichoke patients, changes of VCAM-1 and ICAM-1 were significantly related to changes in brachial FMV (respectively: r=-0.66 and r=-0.62; both p <0.05). In conclusion, artichoke dietary supplementation seems to positively modulate endothelial function in hypercholesterolemia.

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 x m(-2.7); P<0.001), whereas the difference was only 9% in men (50.3+/-12 versus 46.1+/-10 g x 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.

Day-to-day variability of electrocardiographic diagnosis of left ventricular hypertrophy in hypertensive patients. Influence of electrode placement.

OBJECTIVE: Although electrocardiography (ECG) is recommended in all subjects with hypertension, no information is available on the influence exerted by random changes in the placement of electrodes on the day-to-day variability of ECG criteria for diagnosis of left ventricular hypertrophy (LVH). METHODS: In a multicentre, randomized study, two standard 12-lead ECG were recorded, 24 h apart, from 276 consecutive hypertensive patients (mean age 65 +/- 12 years, 49.6% men). Overall, 142 patients were randomized to ECG with the position of electrodes marked on the skin using a dermographic pen and 134 to traditional ECG without marking the position of electrodes. Day-to-day variability of ECG criteria for LVH was compared between the two groups. RESULTS: Coefficients of variation (SD of the difference between paired voltage measurements divided by the mean value) varied consistently among subjects randomized to ECG without dermographic pen, ranging from 30% (R wave in lead I) to 81% (R wave in lead V5). Dermographic pen led to a lesser variability of ECG voltages with consequent reduction in the coefficients of variation, which ranged from 26% (R-wave amplitude in lead I) to 43% (R-wave amplitude in lead V5). The proportion of subjects who changed classification status for LVH ('reclassification rate') from the first to the second ECG session (LVH present in session 1 and absent in session 2, or vice versa) decreased for effect of dermographic pen from 11 to 4% (P = 0.040) with the Cornell voltage, from 19 to 11% (P = 0.029) with the Sokolow-Lyon voltage, and from 18 to 7% with the Romhilt-Estes criterion (P = 0.018), but not with other criteria. In particular, the typical strain and the Cornell strain were associated with the lowest reclassification rates regardless of dermographic pen. CONCLUSIONS: Random changes in the position of ECG electrodes strongly impair the day-to-day reproducibility of Cornell voltage, Sokolow-Lyon and Romhilt-Estes criteria for LVH. The typical strain and Cornell strain criteria showed a lesser spontaneous day-to-day variability.

Attenuation of inflammation with short-term dietary intervention is associated with a reduction of arterial stiffness in subjects with hypercholesterolaemia.

BACKGROUND: Increased arterial stiffness has been found in patients with chronic high-grade inflammatory diseases. Whether mitigation of low-grade systemic inflammation, through a low-cholesterol/low-saturated fat diet, may have a role in improving arterial stiffness is still untested. DESIGN: We investigated whether variations in blood lipids and plasma C-reactive protein induced by low-cholesterol/low-saturated fat diet are associated with variations in large-artery stiffness in hypercholesterolaemia. METHODS: Thirty-five patients with primary hypercholesterolaemia and 15 normal control subjects were recruited for the study. Hypercholesterolaemic patients followed an 8-week low-cholesterol/low-saturated fat diet (30% total fat, 5% saturated fat, cholesterol <200 mg/daily). Anthropometric characteristics, blood lipids, plasma C-reactive protein and arterial stiffness were measured at baseline and after the diet. RESULTS: Arterial stiffness and C-reactive protein levels were higher in hypercholesterolaemic patients than in controls. Significant reductions in body weight (2 kg, 3%), plasma total cholesterol (13.4 mg/dl, 5.3%), low-density lipoprotein cholesterol (11.2 mg/dl, 6.4%), C-reactive protein (0.7 mg/l, 39%) and arterial stiffness (from 8.9+/-2.0 to 8.1+/-1.9 m/s, 11%) were achieved among hypercholesterolaemic patients after the 8-week diet (P<0.05 for all). Bivariate correlations and multivariate analysis showed reduction in arterial stiffness after short-term diet to be associated with reduction of plasma C-reactive protein levels (r=0.59, beta=0.38, P<0.05 for both). CONCLUSIONS: Short-term low-cholesterol/low-saturated fat diet in hypercholesterolaemia may be effective in improving large artery stiffness, likely through the mitigation of low-grade systemic inflammation.