Prevalence of left ventricular hypertrophy and determinants of left ventricular mass in obese women.

BACKGROUND: Obesity is frequently associated with left ventricular hypertrophy (LVH), a condition leading to an increased cardiovascular risk. AIM: The objective of this study was to evaluate the prevalence of LVH in a cohort of obese women, with a main focus on the anthropometric and clinical parameters that are associated with an increased left ventricular mass (LVM). METHODS: The study was performed in 166 obese female patients. LVM was measured by echocardiography. The influence of various parameters on LVM was assessed by multivariate analysis. RESULTS: The prevalence of LVH was drastically different depending on the type of indexed LVM, being 19.9% when the LVM was indexed for body surface area and 72.3% when indexed for height. Age, duration of obesity, weight, waist-to-hip ratio, pulse pressure and hypertension retained an independent direct correlation with the LVM, explaining 39.6% of the overall LVM variability. Among the parameters of the metabolic syndrome, the increase in blood pressure was the main determinant of increased LVM. CONCLUSIONS: By using allometric indexation of LVM for height, the results of our study indicate a high prevalence of LVH in a cohort of obese women. Hypertension, pulse pressure, age, duration of obesity, bodyweight and fat distribution, expressed as waist-to-hip ratio, predict 40% of LVM variation.

Vascular generation of tumor necrosis factor-α reduces nitric oxide availability in small arteries from visceral fat of obese patients.

OBJECTIVES: The aim of this study was to assess whether small arteries from visceral fat of obese patients show a reduced nitric oxide (NO)-dependent relaxation, as compared with lean control subjects, focusing on the role of the pro-inflammatory cytokine tumor necrosis factor (TNF)-α. BACKGROUND: Visceral obesity is characterized by endothelial dysfunction. METHODS: Small arteries from 14 obese (body mass index 48.4 ± 11 kg/m(2)) and 14 control subjects (body mass index 24.9 ± 2 kg/m(2)), dissected after a visceral fat biopsy (laparoscopy), were evaluated on a pressurized micromyograph. Endothelium-dependent relaxation was assessed by acetylcholine. The NO availability, superoxide production, and inflammation were assessed by testing acetylcholine under the nitric oxide synthase (NOS) inhibitor N(ω)-nitro-L-arginine methylester, tempol (superoxide scavenger), and infliximab (monoclonal anti-TNF-α antibody), respectively. The roles of nicotinamide adenine dinucleotide phosphate oxidase and inducible nitric oxide synthase (iNOS) were assessed by their selective inhibitors apocynin and S-methylisothiourea (SMT), respectively. Vascular superoxide generation (dihydroethidium staining) protein expression of TNF-α and NOS isoforms (Western Blot) and TNF-α localization (immunohistochemistry) were assessed. RESULTS: Vessels from obese patients displayed a blunted relaxation to acetylcholine and a reduced inhibitory effect of N(ω)-nitro-L-arginine methylester. These alterations were normalized by tempol or infliximab while being partly ameliorated by apocynin and SMT. Vascular superoxide generation was increased (p < 0.01) in obese patients. This condition was abrogated by both tempol and infliximab and partly (p < 0.05 vs. control subjects) reduced by apocynin or SMT. Enhanced TNF-α and iNOS expression together with increased TNF-α localization in the vascular media were detected. CONCLUSIONS: Small arteries from visceral fat of obese patients are characterized by an increased TNF-α production, which reduces NO availability by promoting superoxide generation via nicotinamide adenine dinucleotide phosphate oxidase and iNOS activation.

Ambulatory monitoring of systolic hypertension in the elderly: Eprosartan/hydrochlorothiazide compared with losartan/hydrochlorothiazide (INSIST trial).

INTRODUCTION: Systolic hypertension is very common in the elderly and is strongly associated with the risk of cardiovascular and cerebrovascular events. The control of systolic hypertension is difficult and most patients require combination antihypertensive therapy. Few data are available regarding the efficacy of angiotensin II receptor antagonists on systolic hypertension of the elderly. The aim of this double-blind, double-dummy, randomized, parallel-group, multicenter study was to assess the efficacy of eprosartan 600 mg in combination with hydrochlorothiazide (HCTZ) 12.5 mg in comparison with losartan 50 mg in combination with HCTZ 12.5 mg, in reducing blood pressure in elderly patients with grade 2 systolic hypertension who did not optimally respond to eprosartan or losartan monotherapy. METHODS: After a 3-week placebo wash-out, 155 patients with an Office trough sitting systolic blood pressure (Office sitSBP) >or=160 mmHg and <180 mmHg were randomized to eprosartan 600 mg (n=78) or losartan 50 mg (n=77) once daily for 6 weeks. In patients not optimally responding to monotherapy (Office sitSBP>or=130 mmHg) 12.5 mg HCTZ was added as fixed combination once daily for 6 weeks. A 24-hour ambulatory blood pressure monitoring (ABPM) was performed at the end of wash-out and at the end of the fixed-combination period. RESULTS: No statistically significant difference was found between eprosartan/HCTZ and losartan/HCTZ on the primary endpoint (24-hour ABPM SBP) with an adjusted mean difference between treatments of 3.1 mmHg (95% CI: -0.32-6.59). However, the mean 24-hour ABPM SBP significantly decreased by 16.7 mmHg with eprosartan/HCTZ and 20.3 mmHg with losartan/HCTZ (P<0.001 vs. baseline). The mean Office sitSBP significantly decreased by 28.7 mmHg and 29.6 mmHg respectively, with eprosartan/HCTZ and losartan/HCTZ (P<0.001 vs.baseline and vs. monotherapy). CONCLUSION: In this study, eprosartan/HCTZ did not demonstrate to be superior to losartan/HCTZ in reducing ABPM systolic hypertension in the elderly.

Effect of sulfaphenazole on tissue plasminogen activator release in normotensive subjects and hypertensive patients.

BACKGROUND: A nitric oxide-independent response, possibly mediated by hyperpolarization, regulates vascular tone, acting as a compensatory mechanism in the presence of impaired nitric oxide availability. Cytochrome P450 2C9 (CYP 2C9) is a source of endothelium-derived hyperpolarizing factors and modulates tissue-type plasminogen activator (tPA) release from endothelial cells; however, no effect of hyperpolarization on fibrinolysis has been documented in humans. We aimed to assess the effect of sulfaphenazole, a specific CYP 2C9 inhibitor, on tPA release in normotensive subjects and patients with essential hypertension. METHODS AND RESULTS: tPA release was measured in the forearm microcirculation of 56 normotensivesubjects and 57 patients with essential hypertension after bradykinin (0.015 microg x 100 mL(-1) x min(-1)) and acetylcholine (1.5 microg x 100 mL(-1) x min(-1)) infusions, with or without sulfaphenazole (0.03 microg x 100 mL(-1) x min(-1)). Bradykinin and acetylcholine infusions were repeated with N(G)-monomethyl-l-arginine (L-NMMA; 100 microg x 100 mL(-1) x min(-1)) and/or sulfaphenazole. tPA release by bradykinin and acetylcholine was higher in normotensive subjects than in patients with essential hypertension (P<0.01). Sulfaphenazole (P<0.01) blunted bradykinin-induced but not acetylcholine-induced tPA release in both groups. In normotensive subjects, L-NMMA infusion reduced tPA release (P<0.01). When L-NMMA was coinfused with sulfaphenazole, tPA release induced by bradykinin, but not by acetylcholine, was further reduced (P<0.01). In patients with essential hypertension, tPA release by both agonists was unaffected by L-NMMA, but only bradykinin-induced tPA release was blunted by sulfaphenazole, alone or with L-NMMA (P<001). CONCLUSIONS: Sulfaphenazole inhibits bradykinin-induced tPA release, which suggests a modulatory role of CYP 2C9-derived endothelium-derived hyperpolarizing factors in tPA release in humans. In patients with essential hypertension, tPA release depends exclusively on endothelium-derived hyperpolarizing factor, which is an ineffective compensatory mechanism in the presence of impaired nitric oxide availability.

Fixed dose combination of perindopril and indapamide improves peripheral vascular function in essential hypertensive patients.

BACKGROUND: The effect on endothelium-dependent and independent vasodilation of 24-week treatment with a fixed-dose combination of perindopril/indapamide (2/0.625 mg, daily) and atenolol (50 mg, daily), was evaluated in 62 untreated essential hypertensive patients according a double-blind, parallel group, randomized study. METHODS: Brachial artery flow-mediated dilation (FMD), response to sublingual glyceril trinitrate (GTN, 25 microg) and to cold pressor test (CPT) were measured at baseline and after treatments at 12 and 24 weeks, as change in diameter from ultrasound scans by a computerized system. RESULTS: Blood pressure (BP) was (P < 0.001) reduced in both groups, but to a greater (P < 0.01) extent in the perindopril/indapamide group. After 24 weeks, FMD was significantly increased (P < 0.01) by perindopril/indapamide (from 5.0 +/- 2.1 to 6.0 +/- 1.7%) but not by atenolol (from 5.1 +/- 1.8 to 5.5 +/- 1.8%). Improvement in FMD was not statistically related to BP reduction. Response to GTN was also significantly (P < 0.05) increased by perindopril/indapamide (from 6.2 +/- 1.9 to 6.9 +/- 1.7%), but not by atenolol (from 6.1 +/- 2.8 to 6.6 +/- 2.6%). Improvement in GTN response was significantly (P < 0.05) related to BP reduction. Response to CPT was significantly increased (P < 0.001) by perindopril/indapamide after 12 and 24 weeks, whereas atenolol significantly (P < 0.05) improved it only after 24 weeks. CONCLUSIONS: Treatment with perindopril/indapamide improves endothelium-dependent vasodilation in comparison with atenolol. This improvement was observed without significant relations with BP changes, suggesting a pressure-independent effect. Improvement in endothelium-independent and sympathetic-associated vasodilation was also observed. These results suggests that long term therapy with a fixed-dose combination of perindopril/indapamide affords vascular protection in hypertensive patients.

Vascular reactivity in patients with undifferentiated connective tissue diseases.

INTRODUCTION: Endothelial dysfunction is an early event in the development of atherosclerotic disease. We investigated endothelial function in the peripheral circulation of patients with undifferentiated connective tissue diseases (UCTDs), in comparison to healthy controls. METHODS: In 15 young UCTD patients (mean age 39 years) with inactive disease and without cardiovascular risk factors and in 15 age-matched controls we evaluated endothelial function in the brachial conduit artery and in the forearm microcirculation. The first district was assessed by flow mediated dilation (FMD) and response to glyceryl trinitrate, and forearm microcirculation by blood flow changes (strain-gauge venous plethysmography) in response to intra-arterial acetylcholine (Ach) and sodium nitroprusside (SNP). Nitric oxide (NO) availability was evaluated by repeating Ach in the presence of intraarterial N(G)-monomethyl-l-arginine (l-NMMA), an NO synthase inhibitor. RESULTS: FMD and response to GTN were similar in UCTD patients and controls. UCTD patients showed a reduced response to Ach (P<0.001) and SNP (P<0.01) as compared to controls. In healthy controls l-NMMA infusion significantly (P<0.001) reduced the vascular response to Ach, while in UCTD patients l-NMMA failed to affect vasodilation to Ach. In UCTD patients, vascular responses were unrelated to clinical manifestations or autoantibody profile. CONCLUSIONS: Young UCTD patients are characterized by reduced endothelium-dependent and -independent vasodilation in the forearm microcirculation, but not in peripheral conduit arteries. Reduced NO availability was indirectly observed. These results suggest that in the absence of traditional risk factors, inactive systemic autoimmune diseases impair NO-dependent but also endothelium-independent vasodilation selectively in the microcirculation.

Arterial stiffness, intima-media thickness and carotid artery fibrosis in patients with primary aldosteronism.

OBJECTIVES: To evaluate vascular wall structure and conduit artery stiffness in patients with primary aldosteronism. METHODS: This observational study, conducted in a University Hypertension Center, evaluated the carotid wall by 2-D ultrasonography and ultrasonic tissue characterization, and analyzed arterial stiffness by applanation tonometer. Twenty-three consecutive patients with primary aldosteronism, 24 matched patients with essential hypertension and 15 controls were studied. Intima-media thickness and corrected integrated backscatter signal of the carotid arteries were evaluated. Radial and femoral pulse wave velocity and aortic augmentation index were also investigated. RESULTS: Intima-media thickness in patients with essential hypertension (0.69 +/- 0.03 mm) was higher (P < 0.04) than that in controls (0.59 +/- 0.02 mm). This finding was more evident in primary aldosteronism patients (0.84 +/- 0.03 mm), in whom intima-media thickness was greater than that in controls (P < 0.0001) or in patients with essential hypertension (P < 0.01). Similarly, corrected integrated backscatter signal in patients with essential hypertension (-23.6 +/- 0.35 dB) was higher (P < 0.0001) than that in controls (-26.2 +/- 0.44 dB), but it was even more elevated in patients with primary aldosteronism (-22.1 +/- 0.46 dB), who showed greater corrected integrated backscatter signal than was the case in patients with essential hypertension (P < 0.009) or in controls (P < 0.0001). Femoral pulse wave velocity was higher in primary aldosteronism patients (10.8 +/- 0.57 m/s) than in patients with essential hypertension (9.1 +/- 0.34 m/s, P < 0.03) or in controls (7.1 +/- 0.51 m/s, P < 0.0001). Femoral pulse wave velocity was lower in controls than in patients with essential hypertension (P < 0.0001). The same pattern was observed for radial pulse wave velocity. Aortic augmentation index was higher in primary aldosteronism patients (28.2 +/- 2.1%) than in patients with essential hypertension (26.0 +/- 1.8%) or in controls (16.8 +/- 2.0%, P < 0.001). Patients with essential hypertension likewise exhibited higher aortic augmentation index than controls (P < 0.001). CONCLUSION: Aldosterone excess is responsible per se for vascular morphological (wall thickening and carotid artery fibrosis) and functional (central stiffness) damage.

Tissue-type plasminogen activator release in healthy subjects and hypertensive patients: relationship with beta-adrenergic receptors and the nitric oxide pathway.

The relationship between adrenergic stimuli and NO in modulating tissue-type plasminogen activator (t-PA) release from endothelial cells was investigated in normotensive subjects and essential hypertensive patients. Sympathetic activation, a well-known stimulus for endogenous fibrinolysis, is also involved in the determination of cardiovascular risk in essential hypertension. However, the existence of cross-talk between adrenergic stimuli and NO availability in modulating t-PA release is not well established yet. We assessed the release of t-PA in the forearm microcirculation of 58 normotensive subjects (mean age: 47+/-9 years) and 44 essential hypertensive patients (mean age: 48+/-11 years) under specific intra-arterial adrenergic stimuli. Intrabrachial infusion of epinephrine (0.1 to 0.3 microg/100 mL per minute) induced greater t-PA release in normotensive subjects as compared with essential hypertensive patients (P<0.05). However, inhibition of NO synthase with N(G)-monomethyl-L-arginine (100 microg/100 mL per minute) infusion blunted epinephrine-induced t-PA release in normotensive subjects (P<0.05) but not in essential hypertensive patients. In normotensive subjects, t-PA release by epinephrine was not affected by phentolamine (8 microg/100 mL per minute) coinfusion and was abolished in the presence of propanolol (10 microg/100 mL per minute). Intrabrachial isoproterenol (0.03 microg/100 mL per minute) induced a significant increase in t-PA release (P<0.01), an effect blunted by N(G)-monomethyl-L-arginine (P<0.05). In essential hypertensive patients, the response to isoproterenol was impaired as compared with normotensive subjects and was unaffected by N(G)-monomethyl-L-arginine coinfusion. In conclusion, the results of the present study demonstrate that adrenergic-induced t-PA release is mediated by beta-adrenoreceptors via a mechanism involving the NO pathway. Our results show an impaired adrenergic-stimulated t-PA release among essential hypertensive patients, probably mediated via a reduced NO availability. This impaired fibrinolytic activity might contribute to the increased cardiovascular risk associated with hypertension.

Peripheral wave reflection and endothelial function in untreated essential hypertensive patients with and without the metabolic syndrome.

OBJECTIVE: Metabolic syndrome is associated with a high risk of cardiovascular disease in hypertension. We evaluated whether metabolic syndrome is associated with early vascular alterations, such as increased peripheral wave reflections and endothelial dysfunction, in untreated essential hypertensive patients. METHODS: Augmentation index and pulse wave velocity were determined with applanation tonometry in 391 untreated hypertensive patients and 166 controls. Endothelium-dependent response was assessed as flow-mediated dilation of the brachial artery. Metabolic syndrome was defined according to the latest National Cholesterol Education Program Adult Treatment panel III. RESULTS: Hypertensive patients showed significantly (P < 0.001) increased augmentation index and central pulse wave velocity, as well as reduced flow-mediated dilation, compared with controls. No further impairment in augmentation index or flow-mediated dilation was observed between patients with or without the metabolic syndrome components and with increasing number of metabolic syndrome. Age and systolic blood pressure, but no other single factor of the metabolic syndrome, resulted as significant predictors of augmentation index and flow-mediated dilation. Female gender was associated with increased augmentation index (P < 0.05) in the presence of the metabolic syndrome. Central pulse wave velocity was selectively impaired by metabolic syndrome in both genders. Finally, reactive hyperemia was reduced in patients with the metabolic syndrome and decreased significantly with the increasing number of metabolic syndrome. CONCLUSIONS: In untreated hypertensive patients, the presence of metabolic syndrome, which selectively impairs central pulse wave velocity, does not account for a further deterioration of peripheral wave reflection and conduit artery endothelial function. Our results suggest that blood pressure, age and gender are important determinants of peripheral vascular structural and functional parameters in these subjects, irrespective of the metabolic syndrome.

Normalization of catecholamine production following resection of phaeochromocytoma positively influences carotid vascular remodelling.

OBJECTIVE: To evaluate the influence of plasma catecholamines on the vascular structure in humans, the effects of catecholamine normalization on the carotid wall of patients with phaeochromocytoma (PHEO) were investigated. A prospective study in patients with PHEO before and after (first follow-up: 20.5+/-1.8 months, second follow-up: 31.5+/-2.2 months) successful surgery was conducted in the University Referral Center for Blood Pressure Diseases. Ten consecutive patients with PHEOs and ten age- and blood pressure-matched controls were investigated. Intima-media thickness (IMT) by two-dimensional conventional ultrasonography and corrected ultrasonic integrated backscatter signal (C-IBS) analysis of carotid arteries were investigated in basal conditions and after mass removal. RESULTS: In PHEOs, at variance with the expected reduction in metanephrines and catecholamines, no variation in body weight, blood pressure and lipid profile was observed after operation. IMT and C-IBS values in patients with PHEO were greater (at least P<0.01) than in controls. At long-term follow-up after surgery, a significant reduction in mean carotid IMT (P<0.0009) and C-IBS (P<0.009) values was observed. A significant correlation (r=0.54, P<0.03) was found between absolute reduction in C-IBS values and absolute decrement in urinary normetanephrine levels. CONCLUSIONS: Our study shows that normalization of catecholamine levels after the removal of PHEO improves carotid IMT and reduces carotid wall fibrosis even without influencing blood pressure and lipid profile. These findings confirm that high catecholamine tone in humans directly influences vascular remodelling of carotid arteries.

Plasma and urine aldosterone to plasma renin activity ratio in the diagnosis of primary aldosteronism.

OBJECTIVE: To establish the best cut-off value of the aldosterone (ALD)/plasma renin activity (PRA) ratio when screening patients for primary aldosteronism. One hundred and six patients with primary aldosteronism and 100 essential hypertensive patients were investigated in rigorous standardized conditions. METHODS: The ALD/PRA cut-off values were calculated from both the plasma and urine ALD/PRA ratio and analyzed by receiver operating characteristic (ROC) curve. In patients with PRA below 0.2 ng/ml/h [our radioimmunoassay detection limit], values were calculated both with PRA levels set at 0.2 ng/ml/h ('adjusted') and with PRA levels detected ('unadjusted') in the assay. RESULTS: ROC analysis on the ALD/PRA ratio indicated that the best performance was obtained when the plasma ALD (ng/dl)/PRA ratio was used in comparison with that observed in the urine ALD (microg/day)/PRA ratio. In patients with primary aldosteronism, as a whole group, the cut-off value of 69 corresponded to the best compromise value between sensitivity (96%) and specificity (85%), with and without PRA adjustment. In patients with aldosterone-producing adenoma, the cut-off to obtain 100% sensitivity with high specificity (85%) proved to be 69, with and without PRA adjustment. In patients with bilateral adrenal hyperplasia, both with and without PRA adjustment, the best compromise between sensitivity (94%) and specificity (86%) was a cut-off value of 71. CONCLUSION: The best cut-off to identify patients with primary aldosteronism, corresponding to 69, was obtained by using the plasma ALD/PRA ratio. Adjustment of PRA to 0.2 ng/ml/h does not interfere with calculation of the plasma ALD/PRA ratio cut-off.

Metabolic syndrome and vascular alterations in normotensive subjects at risk of diabetes mellitus.

We evaluated the possible association between early vascular abnormalities and the metabolic syndrome (MS) in 77 normotensive subjects (mean age: 50 years) at risk of developing diabetes for family history of diabetes, obesity, or impaired fasting glucose. Fifty healthy subjects were recruited as controls. MS was defined according to the ATP III criteria. Brachial artery endothelium-dependent and -independent vasodilation were assessed as flow-mediated dilation (FMD) and response to glyceryl trinitrate (GTN, 25 microg sublingual), respectively, by automatic computerized edge detection system. Carotid-femoral pulse wave velocity (PWV) and radial augmentation index (AIx) were assessed by applanation tonometry. PWV was significantly (P<0.01) higher in subjects with MS (n=29, 9.0+/-1.9 m/s) as compared with those without MS (n=48, 7.7+/-1.2 m/s) and controls (7.2+/-1.5 m/s). FMD was significantly (P<0.05) reduced in both subjects with (5.8+/-2.7%) and without MS (6.1+/-3.7%) as compared with controls (6.9+/-2.5%). No significant differences were found for response to GTN and AIx. PWV and FMD were significantly (P<0.05) affected by increasing number of MS components. Among the components of the MS, only blood pressure significantly affected PWV, whereas blood pressure and fasting glucose influenced FMD. Logistic regression analysis showed that MS was associated with increased risk of altered PVW (odd ratio: 7.95, confidence limits: 1.06 to 69.11), whereas only blood pressure component was significantly related with increased risk of impaired FMD (odd ratio: 3.60, confidence limits: 1.01 to 12.78). In conclusion, in normotensive subjects at risk of developing diabetes mellitus, the presence of MS is associated with a selective alteration of central PWV.

Omega 3 : where do we stand?

Omega-3 fatty acids are essential polyunsaturated fatty acids that are crucial components of plasma membrane phospholipids. They influence cell structure and function and have anti-thrombotic and anti-arrhythmic properties, thus potentially exerting a favourable action on primary and secondary prevention of cardiovascular events. However, the supposed beneficial effect of omega-3 fatty acids in the management of cardiovascular risk has been evaluated only in a relatively small number of interventional studies, with results that are not consistent and are only suggestive of a putative beneficial effect of omega-3 supplementation on the prevention of cardiovascular mortality. Benefits have been reported mainly for the prevention of sudden death in patients with recent myocardial infarction and for primary and secondary prevention of nonfatal cardiac events in populations with high fish intake. Therefore, only ongoing trials will provide definitive data to elucidate whether omega-3 fatty acids could represent a new therapeutic approach for cardiovascular disease.

Preclinical cardiac involvement in phaeochromocytoma: a study with integrated backscatter.

OBJECTIVE: It is well known that vascular and cardiac structure may be influenced by circulating neurohormonal factors. Our aim was to study the myocardial wall texture by integrated backscatter (IBS) analysis in patients with phaeochromocytoma (PHEO). DESIGN: Fourteen patients with PHEO, 15 matched high-normal blood pressure (BP) subjects, 15 mild essential hypertensives and 15 normotensive controls underwent two-dimensional conventional ultrasonography and ultrasonic IBS of the myocardial wall. IBS analysis was performed at both interventricular septum and posterior wall levels. IBS values were expressed in decibels and corrected for the IBS values obtained within the pericardium (C-IBS). The systo-diastolic cyclical variations in IBS (CV-IBS), an index of myocardial contractile performance, were also evaluated. RESULTS: Patients with PHEO showed C-IBS values comparable to those of hypertensive patients, and significantly higher than those of high-normal BP subjects and controls at both septum and posterior wall levels (P < 0.001 for all). In PHEO patients, CV-IBS was lower than that of normotensive, high-normal BP subjects and hypertensive patients, at both septum and posterior wall levels (P < 0.001 for all). An inverse relationship was found in the PHEO group between 24-h urinary normetanephrine and CV-IBS of both septum (r(2) = -0.29, P < 0.05) and posterior wall (r(2) = -0.46, P < 0.05). CONCLUSIONS: Our results show that patients with PHEO have myocardial remodelling characterized by increased myocardial fibrosis, confirmed by an increase in the overall myocardial backscatter level measured. The observed decrease in the magnitude of CV-IBS suggests an impairment of myocardial contractile performance. These results may provide insights into the role of catecholamines in left ventricular (LV) structure and function in PHEO.

Left ventricular diastolic dysfunction in elderly hypertensives: results of the APROS-diadys study.

BACKGROUND: A number of patients with chronic heart failure (CHF) have diastolic but not systolic dysfunction. This occurs particularly in the elderly and in hypertension, but the prevalence of diastolic dysfunction in elderly hypertensives without CHF has never been investigated systematically. METHODS AND RESULTS: The Assessment of PRevalence Observational Study of Diastolic Dysfunction (APROS-diadys) project was a cross-sectional observational study on elderly (age >/= 65 years) hypertensives without systolic dysfunction [left ventricular ejection fraction (LVEF) >/= 45%] consecutively attending hospital outpatient clinics in Italy, in order to establish the prevalence of echocardiographic signs of diastolic dysfunction according to various criteria, and to correlate them with a number of demographic and clinical characteristics. Primary criteria for diastolic dysfunction was an E/A ratio (ratio between transmitral peak velocities of E and A waves) < 0.7 or > 1.5 on echocardiographic Doppler examination. Secondary criteria were: E/A < 0.5 and deceleration time (DT) > 280 ms, or isovolumic relaxation time (IVRT) > 105 ms or pulmonary vein (PV) peak systolic/peak diastolic flow (S/D) ratio > 2.5 or PV atrial retrograde flow (PV A) > 35 cm/s. Throughout Italy, 27 447 patients were screened in 107 clinics, with 24 141 excluded according to protocol. Among the remaining 3336 patients, 754 (22.6%) had signs of CHF. After exclusion of 37 protocol violators, 2545 patients (49.0% men, mean age 70.3 years, 95.4% under antihypertensive treatment) were studied ultrasonographically. Diastolic dysfunction (primary criteria) was found in 649 (25.8%) patients. Multiple logistic regression analysis found age, gender, left ventricular mass, systolic and pulse pressures and midwall shortening fraction as significant covariates. Using secondary criteria, the prevalence of diastolic dysfunction was higher (45.6%), mostly because of IVRT > 105 ms or PVA flow > 35 cm/s. CONCLUSION: CHF and diastolic dysfunction are highly prevalent in elderly hypertensives attending hospital clinics.

Nitric oxide modulates tissue plasminogen activator release in normotensive subjects and hypertensive patients.

We evaluated the possible role of NO in modulating tissue plasminogen activator (t-PA) release in the forearm microcirculation of normotensive subjects and hypertensive patients. Essential hypertensive patients are characterized by endothelial dysfunction because of a reduced NO availability and also show an impaired t-PA release. In healthy volunteers and essential hypertensive patients, we studied local t-PA release and forearm blood flow changes (strain-gauge plethysmography) induced by intrabrachial administration of acetylcholine (0.45 and 1.5 microg/100 mL/min) and of sodium nitroprusside (0.5 and 1.0 microg/100 mL/min), an endothelium-dependent and -independent agonist, respectively. Acetylcholine was also repeated in the presence of intra-arterial infusion of the NO synthase inhibitor N(G)-monomethyl-l-arginine (100 microg/100 mL/min). In normotensive subjects, vasodilation to acetylcholine was blunted by N(G)-monomethyl-l-arginine. In these subjects, acetylcholine infusion induced a significant, dose-dependent increase in net forearm t-PA release. N(G)-monomethyl-l-arginine significantly reduced basal t-PA release, as well as acetylcholine-induced t-PA release. In essential hypertensive patients, vasodilation to acetylcholine was reduced as compared with controls and resistant to N(G)-monomethyl-l-arginine. In contrast to what was observed in healthy control subjects, in hypertensive patients, acetylcholine had no effect on t-PA release. Similarly, N(G)-monomethyl-l-arginine failed to modify either the tonic or the agonist-induced t-PA release. Both tonic and agonist-induced release of NO are directly involved in t-PA release by endothelial cells. Essential hypertension, characterized by a reduction in tonic and stimulated NO availability, is also associated with impaired capacity of t-PA release, suggesting a major role of impaired NO availability in worsening both vasodilation and t-PA release.

Supplementation with vitamins C and E improves arterial stiffness and endothelial function in essential hypertensive patients.

BACKGROUND: Essential hypertension is characterized by endothelial dysfunction, arterial stiffness, and increased oxidative stress. We evaluated the effect of short-term combined treatment with the antioxidants vitamins C and E on endothelial function, arterial stiffness, and oxidative stress in untreated essential hypertensive patients. METHODS: A randomized, double-blind, placebo-controlled, crossover study design was used to assign 30 male essential hypertensive patients to either vitamin C (1 g) and vitamin E (400 IU) or placebo for 8 weeks. Endothelium-dependent response was assessed as flow-mediated dilation (FMD) of the brachial artery. Arterial stiffness was assessed as central pulse wave velocity (PWV) and augmentation index (AIx). Plasma markers of oxidative stress and antioxidant status were measured. RESULTS: After vitamin supplementation, FMD was significantly improved. Central PWV was significantly reduced, while AIx tended to decrease. Plasma vitamin levels and antioxidant capacity increased significantly. Levels of oxidative stress decreased. Changes in central PWV were related to changes in levels of oxidative stress. CONCLUSIONS: Combined treatment with vitamins C and E has beneficial effects on endothelium-dependent vasodilation and arterial stiffness in untreated, essential hypertensive patients. This effect is associated with changes in plasma markers of oxidative stress.

Ramipril dose-dependently increases nitric oxide availability in the radial artery of essential hypertension patients.

DESIGN AND PARTICIPANTS: A double-blind, crossover, randomized study was designed to evaluate the effect of 3-month treatment with a lower versus a higher antihypertensive dosage of ramipril (5 or 10 mg/day) on nitric oxide (NO)-dependent vasodilation in 46 untreated patients with essential hypertension. Radial artery flow-mediated dilation (FMD), before and after the intra-arterial infusion of NG-monomethyl-L-arginine (L-NMMA), to block NO synthase, and the response to sublingual glyceril trinitrate (GTN, 25 microg) were measured at baseline and after the two treatment periods as a change in artery diameter (computerized system from ultrasound scans). Plasma angiotensin II and oxidative stress markers were also assessed. RESULTS: FMD was significantly (P < 0.01) lower in hypertensive patients (4.6 +/- 1.8%) than in normotensive subjects (7.1 +/- 2.6%), whereas the response to GTN was similar. L-NMMA significantly (P < 0.001) inhibited FMD in normotensive but not in hypertensive subjects. Mean 24-h ambulatory blood pressure, plasma angiotensin II and oxidative stress marker levels were similarly reduced at the end of the two treatment periods. Both dosages of ramipril significantly (P < 0.001) increased FMD (5 mg: 5.9 +/- 2.1%; 10 mg: 6.3 +/- 2.4%) without modifying the response to GTN. However, compared with baseline (11 +/- 19%), the inhibiting effect of L-NMMA on FMD (NO-dependent FMD) was significantly (P < 0.01) greater with ramipril 10 mg (49 +/- 12%) than 5 mg per day (38 +/- 15%). The improvement in FMD and NO-dependent FMD was not related to changes in plasma levels of angiotensin II or markers of oxidative stress. CONCLUSION: Treatment with ramipril at a higher dosage induced a greater improvement in NO-dependent vasodilation compared with the lower antihypertensive dosage in hypertensive patients.

Soy protein diet improves endothelial dysfunction in renal transplant patients.

BACKGROUND: Since it has been demonstrated that soy diet can improve endothelial function, in the present study we evaluated the effect of dietary substitution of 25 g of animal proteins with soy proteins on endothelial dysfunction in renal transplant patients. METHODS: In 20 renal transplant patients (55 +/- 11 years, serum creatinine 1.7 +/- 0.6 mg/dl), brachial artery flow mediated dilation (FMD) and endothelium-independent vasodilation (sublingual nitroglycerine, 25 microg) were measured at baseline, after 5 weeks of a soy diet and finally after 5 weeks of soy wash-out. Changes in plasma lipids, markers of oxidative stress (lipid peroxides, LOOH) and inflammation (C-reactive protein), isoflavones (genistein and daidzein), asymmetric dimethyl arginine (ADMA) and L-arginine were also evaluated. RESULTS: At baseline, patients showed a significantly lower FMD as compared with age-matched healthy subjects (3.2 +/- 1.8 vs 6.3 +/- 1.9, respectively; P < 0.001), while response to nitroglycerine was similar. After soy diet, actual protein intake was not changed, cholesterol and lipid peroxides were significantly reduced, and isoflavones were detectable in plasma. Soy diet was associated with a significant improvement in FMD (4.4 +/- 2.0; P = 0.003 vs baseline), while response to nitroglycerine was unchanged. Improvement in FMD was related to L-arginine/ADMA ratio changes, but no significant relation was found to changes in cholesterol, lipid peroxides or genistein and daidzein plasma concentrations. After 5 weeks of soy diet discontinuation, FMD (3.3 +/- 1.7%) returned to baseline values and isoflavones were no longer detectable in plasma. CONCLUSIONS: A soy protein diet for 5 weeks improves endothelial function in renal transplant patients. This effect seems to be strictly dependent on soy intake as it disappears after soy withdrawal and is mediated by an increase in the L-arginine/ADMA ratio, independently of change in lipid profile, oxidative stress or isoflavones.