Role of renin–angiotensin aldosterone system on short-term blood pressure variability in hypertensive patients

The relationship between the renin–angiotensin aldosterone system and short-term blood pressure variability has not been well elucidated. Here, we investigated whether blood pressure variability determined by ambulatory blood pressure monitoring differed among patients with primary aldosteronism (PA), renovascular hypertension (RVHT), and essential hypertension (EHT). We examined 25 patients with PA, 28 patients with RVHT, and 18 patients with EHT. Ambulatory blood pressure monitoring was conducted in all patients. Short-term blood pressure variability was evaluated by calculating the standard deviation (SD), coefficient of variation (CV), and average real variability (ARV) of 24-h, daytime, and nighttime blood pressure values. Day–night differences in blood pressure were also determined. The mean 24-h systolic blood pressure (SBP) and the mean diastolic blood pressure (DBP) in the PA and RVHT groups were found to be comparable to those in the EHT group. The SD, the CV, nor the ARV of the 24-h, daytime, and nighttime blood pressures showed any significant differences among the three groups. The day–night differences in blood pressure were comparable among the three groups. The short-term blood pressure variabilities evaluated by ambulatory blood pressure monitoring were comparable among the patients with EHT, RVHT, and PA. The results suggest that the renin–angiotensin aldosterone system may contribute little to short-term blood pressure variability in individuals with hypertension.     

Left ventricular structural characteristics in unilateral renovascular hypertension and primary aldosteronism

To assess the importance of the renin-angiotensin system and plasma volume as determinants of hypertensive left ventricular hypertrophy and its anatomy, patients with unilateral renovascular hypertension and primary aldosteronism were studied by echocardiography. Blood pressure, age and sex were matched as closely as possible. The 19 patients with unilateral renovascular hypertension and the 19 patients with primary aldosteronism were similar in age, sex and blood pressure (168 +/- 19/97 +/- 11 and 163 +/- 17/99 +/- 10 mm Hg, respectively), but plasma volume was increased in the patients with primary aldosteronism. Interventricular septal thickness, left ventricular posterior wall thickness, left ventricular mass index and relative wall thickness did not differ between the 2 groups of patients. There was a significant correlation between the level of systolic blood pressure and either left ventricular mass index (r = 0.34, p less than 0.05) or relative wall thickness (r = 0.58, p less than 0.001) in both groups of patients. Left ventricular end-diastolic dimension index was increased in the patients with primary aldosteronism compared with those with unilateral renovascular hypertension (3.2 +/- 0.4 vs 2.9 +/- 0.3 cm/m2, p less than 0.02). When confined to the patients with systolic pressure greater than or equal to 150 mm Hg, relative wall thickness was significantly increased in the patients with unilateral renovascular hypertension. Patients with primary aldosteronism and unilateral renovascular hypertension of similar blood pressure levels, age and sex have almost identical degrees of left ventricular hypertrophy and anatomy. In contrast, the patients with primary oldosteronism had increased left ventricular dimension index.(ABSTRACT TRUNCATED AT 250 WORDS)     

Influence of the arterial blood pressure and nonhemodynamic factors on left ventricular hypertrophy in moderate essential hypertension.

In a group of 36 untreated patients with mild to moderate essential hypertension (office systolic and diastolic blood pressures (BPs) 160 +/- 3.4 and 102 +/- 1.5 mm Hg, respectively), a 24-hour ambulatory BP monitoring and determination of left ventricular (LV) mass index according to the formula of Devereux were performed. After an overnight fast, blood samples were taken for the determination of serum aldosterone, plasma renin activity and serum parathyroid hormone. Urinary catecholamines were sampled for 24 hours. LV mass index (143.7 +/- 8 g/m2) did not correlate significantly either with office systolic or diastolic BP. The correlation of LV mass index with mean 24-hour systolic BP (145 +/- 3 mm Hg) was statistically significant: r = 0.395, p = 0.026. However, the best correlation was obtained with mean 24-hour diastolic BP (90 +/- 3 mm Hg) with r = 0.500 (p = 0.004). Urinary catecholamines were not correlated with LV mass index. LV mass index correlated significantly with plasma renin activity (r = 0.346, p = 0.050), and aldosterone (r = 0.559, p = 0.001). There was a very significant correlation between LV mass index and parathyroid hormone (r = 0.719, p = 0.00001) even after adjustment for mean 24-hour systolic and diastolic BPs. These results clearly demonstrate that ambulatory BP determinants but not office BP parameters are well correlated with LV hypertrophy in essential hypertension. Nonhemodynamic factors are important determinants of LV mass as well. Besides the renin-angiotensin-aldosterone system, parathyroid hormone appears to play an important role in cardiac hypertrophy.     

Aldosterone excess and resistance to 24-h blood pressure control

BACKGROUND: Aldosterone excess has been reported to be a common cause of resistant hypertension. To what degree this represents true treatment resistance is unknown. OBJECTIVE: The present study aimed to compare the 24-h ambulatory blood pressure monitoring (ABPM) levels in resistant hypertensive patients with or without hyperaldosteronism. METHODS: Two hundred and fifty-one patients with resistant hypertension were prospectively evaluated with an early-morning plasma renin activity (PRA), 24-h urinary aldosterone and sodium, and 24-h ABPM. Daytime, night-time, and 24-h blood pressure (BP) and nocturnal BP decline were determined. Hyperaldosteronism (H-Aldo) was defined as suppressed PRA (<1.0 ng/ml per h or <1.0 mug/l per h) and elevated 24-h urinary aldosterone excretion (>/= 12 mug/24-h or >/= 33.2 nmol/day) during ingestion of the patient's routine diet. RESULTS: In all patients, the mean office BP was 160.0 +/- 25.2/89.4 +/- 15.3 mmHg on an average of 4.2 medications. There was no difference in mean office BP between H-Aldo and normal aldosterone status (N-Aldo) patients. Daytime, night-time, and 24-h systolic and diastolic BP were significantly higher in H-Aldo compared to N-Aldo males. Daytime, night-time, and 24-h systolic BP were significantly higher in H-Aldo compared to N-Aldo females. Multivariate analysis indicated a significant interaction between age and aldosterone status such that the effects of aldosterone on ambulatory BP levels were more pronounced with increasing age. CONCLUSIONS: In spite of similar office BP, ABPM levels were higher in resistant hypertensive patients with H-Aldo. These results suggest that high aldosterone levels impart increased cardiovascular risk not reflected by office BP measurements.     

Cytosolic free calcium concentration in platelets in patients with renovascular hypertension and primary aldosteronism.

To investigate the role of cytosolic free calcium, [Ca2+]i, in secondary hypertension, the levels in platelets from 14 secondary hypertensives (7 renovascular hypertension, 7 primary aldosteronism) were compared with those from 21 essential hypertensives and 15 normotensives by means of the fluorescent indicator, quin-2. The mean BP was significantly higher in both the secondary hypertensives and essential hypertensives (122 +/- 8 and 124 +/- 12 mmHg) than in the normotensives (89 +/- 10 mmHg). Cytosolic free calcium in platelets was significantly higher in the essential hypertensives, but not in the secondary hypertensives, compared with the normotensives (182 +/- 34, 141 +/- 17, 138 +/- 15 nM respectively). There was no significant difference in platelet [Ca2+]i between renovascular hypertension and aldosteronism (142 +/- 19 versus 139 +/- 16 nM). There was no correlation between platelet [Ca2+]i and plasma renin activity, plasma aldosterone concentration or plasma noradrenaline concentration in the three groups. Thus, the increase in platelet [Ca2+]i seen in essential hypertension was not found in patients with secondary hypertension. Our results suggest that the cytosolic calcium handling of secondary hypertensive patients with renal artery stenosis or primary aldosteronism differs from that of essential hypertensives.     

Nurse-recorded and ambulatory blood pressure predicts treatment-induced reduction of left ventricular hypertrophy equally well in hypertension: results from the Swedish irbesartan left ventricular hypertrophy investigation versus atenolol (SILVHIA) study

OBJECTIVE : To compare the relationships of treatment-induced reductions of left ventricular hypertrophy to the changes in clinic and ambulatory blood pressure (BP). DESIGN : Double-blind and randomized treatment with irbesartan or atenolol for 48 weeks. PATIENTS : Patients with hypertension and left ventricular hypertrophy (n = 66) with a seated diastolic BP 90-115 mmHg (average of three measurements one minute apart by nurses). MAIN OUTCOME MEASURES : Registrations of echocardiographic left ventricular (LV) mass. Clinic and ambulatory BP. RESULTS : In the total material, nurse-measured BP was reduced by 23 +/- 15/16 +/- 7.7 mmHg and 24-h ambulatory BP fell 20 +/- 15/14 +/- 8.5 mmHg by treatment. The correlation between the change in nurse-measured BP and LV mass index (LVMI) induced by treatment was r = 0.35, P = 0.004 for systolic BP and r = 0.26, P = 0.03 for diastolic BP. Corresponding values for 24-h ambulatory BP were r = 0.29, P = 0.02 and r = 0.35, P = 0.004, respectively, with similar correlations for day- and night-time ambulatory BP. The nurse-recorded BP was slightly higher than ambulatory BP (systolic clinic - systolic 24-h ambulatory BP = 5 mmHg). Using 130/80 mmHg as a cut-off value for normal 24-h ambulatory BP, eight subjects had normal diastolic or systolic ambulatory BP, or both. Interestingly, these patients also experienced LVMI regression following treatment (low/normal ABP, -13 +/- 21 g/m2; remaining patients, -18 +/- 22 g/m2, P > 0.5). CONCLUSIONS : In patients with hypertension and left ventricular hypertrophy, ambulatory BP is not superior to carefully standardized nurse-recorded seated BP in terms of associations with treatment-induced changes in LV mass.     

The correlation between isolated interventricular septal hypertrophy and 24-h ambulatory blood pressure monitoring in apparently healthy air crew

BACKGROUND: Interventricular septal (IVS) hypertrophy is considered to affect prognosis in hypertensive patients. However, the natural history of isolated septal hypertrophy, identified by echocardiography in otherwise healthy subjects is not well defined. METHODS: The study population included 51 apparently healthy pilots with septal hypertrophy (septal thickness > 11 mm) defined by routine echocardiography, with a calculated normal left ventricular (LV) mass. All pilots underwent casual blood pressure (BP) measurements and a 24-h ambulatory BP monitoring (ABPM). Hypertension (HTN) was defined as a casual measurement of > 140/90 mmHg. RESULTS: The mean age of the pilots was 38 +/- 11 years and the body mass index (BMI) 26.3 kg/m(2). The 17 pilots found to be hypertensive had a higher septal thickness than the 34 counterparts with normal BP measurements (13.8 +/- 2.0 mm versus 12.6 +/- 1.7 mm, P < 0.04, respectively). The mean ambulatory daytime systolic and diastolic BP were higher in comparison to non-hypertensive pilots (142 +/- 6.2 versus 128 +/- 5.0 mmHg, P < 0.0001 for systolic BP and 91 +/- 5.3 versus 78 +/- 4.1 mmHg, P = 0.001 for diastolic BP), respectively. The adjusted relative risk (RR) of a subject with an IVS thickness P > 12 mm to be hypertensive by ABPM was 3.12 (95% confidence interval 1.04-9.37, P < 0.02). CONCLUSIONS: Isolated IVS hypertrophy, even in the presence of normal LV mass is associated with HTN. Screening healthy subjects at risk for hypertension by echocardiography enables one to identify those who should be closely monitored, using among others, ABPM.     

Increased intima-media thickness of the common carotid artery in primary aldosteronism in comparison with essential hypertension

BACKGROUND: Aldosterone contributes to the accumulation of collagen fibers and extracellular matrix in arterial wall. The aim of this study was to compare intima-media thickness (IMT) of the common carotid artery and carotid bifurcation in patients with primary aldosteronism, essential hypertension and healthy controls. METHODS: Carotid ultrasound studies were carried out in 33 patients aged 42-72 years with primary aldosteronism, 52 patients with essential hypertension and in 33 normotensive controls. RESULTS: The patients with primary aldosteronism had significantly higher IMT of the common carotid artery than patients with essential hypertension and controls (0.987 +/- 0.152 mm; 0.892 +/- 0.154 mm versus 0.812 +/- 0.124 mm; P < 0.001; P < 0.05). There was also significantly higher IMT of the common carotid in patients with essential hypertension compared to control group (0.892 +/- 0.154 mm versus 0.812 +/- 0.124 mm; P < 0.01). The differences between both hypertensive groups remained statistically significant after adjustment for age and 24-h systolic blood pressure (P = 0.001). The differences of the IMT in the carotid bifurcation were statistically significant only between patients with primary aldosteronism and controls (1.157 +/- 0.243 mm versus 0.994 +/- 0.199 mm; P <0.05). CONCLUSION: Patients with primary aldosteronism have increased common carotid IMT compared to the patients with essential hypertension. This finding could be caused by the deleterious effects of aldosterone excess on the fibrosis and thickening of the arterial wall, mainly in the straight segments of vessels.     

Structural changes in small resistance arteries and left ventricular geometry in patients with primary and secondary hypertension

OBJECTIVE : To prospectively evaluate the interrelationships between left ventricular (LV) geometry and structural characteristics of the vessel wall in small resistance arteries in patients with consecutive primary and secondary hypertension. METHODS : In 14 patients with phaeochromocytoma, 12 with primary aldosteronism, 25 with renovascular, 25 with essential hypertension and 12 normotensive controls, an echocardiographic study for the measurement of LV mass index and relative wall thickness (RWT) was performed. Morphological characteristics of small resistance arteries (relaxed diameter < 300 microm) were directly evaluated by a micromyographic technique. RESULTS : A total of 25 patients had normal LV mass and geometry, 28 patients had normal RWT (< 0.45) and 23 patients had a RWT >or= 0.45; all normotensive subjects had normal LV mass and geometry. Media to lumen ratio (M/L) in subcutaneous small arteries was greater in hypertensive patients with concentric LV hypertrophy in respect to normotensives (ANOVA P = 0.01) and hypertensives with normal LV geometry (ANOVA P = 0.05). In the whole group of hypertensive patients the correlation coefficient between M/L and LV mass index was 0.33 (P < 0.05); the correlation coefficient between M/L and RWT was 0.46 (P < 0.01) and it was higher in primary aldosteronism (r = 0.67) and renovascular hypertension patients (r = 0.46). CONCLUSIONS : A close relation between morphology of subcutaneous small resistance arteries and LV geometric patterns may be observed in hypertensive patients; this relationship is more evident when the renin-angiotensin-aldosterone system is activated.     

Type 2 diabetes is associated with left ventricular concentric remodeling in hypertensive patients

BACKGROUND: Left ventricular (LV) geometric remodeling is associated with cardiovascular prognosis in hypertensive patients. It is uncertain how LV remodeling is modulated by diabetes in hypertensive patients. In this study, we investigated the impact of diabetes and ambulatory blood pressure (BP) on LV geometric remodeling in hyptensives with/without diabetes. METHODS: Ambulatory BP monitoring and echocardiography were performed to compare 24-h BP levels and LV measurements in 400 uncomplicated hypertensives (mean age, 67 years, 152 men and 248 women) between diabetic (n = 161) and nondiabetic (n = 239) patients. RESULTS: The age (67 v 68 years), percentage of men (43% v 34%), body mass index (24.5 v 24.0 kg/m(2)), 24-h systolic BP (144/80 v 144/82 mm Hg), LV mass index (128 v 130 g/m(2)) were similar between the groups. Diabetic patients had higher relative wall thickness (0.50 v 0.44, P < .001) and higher prevalence of concentric LV hypertrophy (39.4% v 26.8%, P < .001) than nondiabetic patients. The presence of diabetes (odds ratio [OR] = 2.76; 95% confidence interval [CI] = 1.73-4.41, P < .001) and 24-h systolic BP (OR for 10 mm Hg increase = 1.17; 95% CI = 1.01-1.37, P < .05) were independently associated with the higher relative wall thickness (>/=0.45). On the other hand, 24-h systolic BP was independently associated with LV hypertrophy (OR for 10 mm Hg increase = 1.32; 95% CI = 1.14-1.52, P < .05). CONCLUSIONS: Among hypertensive patients, type 2 diabetes was associated with concentric LV geometry independent of ambulatory BP.     

Myocardial ultrasonic backscatter in hypertension: relation to aldosterone and endothelin

A disproportionate accumulation of fibrillar collagen is a characteristic feature of hypertensive heart disease, but the extent of myocardial fibrosis may differ in different models of hypertension. In experimental studies, aldosterone and endothelins emerge as important determinants of myocardial fibrosis. Changes in myocardial extracellular matrix and collagen deposition can be estimated noninvasively by analysis of the ultrasonic backscatter signal, which arises from tissue heterogeneity within the myocardium and describes myocardial texture. This study was designed to investigate the relations between myocardial integrated backscatter and circulating aldosterone and immunoreactive endothelin in human hypertension. The study population consisted of 56 subjects: 14 healthy normotensive volunteers and 42 hypertensive patients (14 with primary aldosteronism, 7 with renovascular hypertension, and 21 with essential hypertension). The patients with essential and secondary hypertension were matched for age, gender, body mass index, and blood pressure. Myocardial integrated backscatter at diastole was 19.8+/-2.0 and 20.8+/-2.9 decibels in normotensive control subjects and patients with essential hypertension and significantly higher in patients with primary aldosteronism (27.4+/-3.8 decibels, P<0.01) and renovascular hypertension (26.8+/-4.8 decibels, P<0.01). In the population as a whole, as well as in the hypertensive subpopulation, myocardial integrated backscatter was directly related to plasma aldosterone (r=0.73 and 0.71, P<0.01 for both) and immunoreactive endothelin (r=0.60 and 0.56, P<0.01 for both). The data of this study suggest that in human hypertension, circulating aldosterone and immunoreactive endothelin may induce alterations in left ventricular myocardial texture, possibly related to increased myocardial collagen content.     

Left ventricular concentric remodelling and extracardiac target organ damage in essential hypertension

Left ventricular (LV) concentric remodelling is an adaptive change in cardiac geometry frequently observed in arterial hypertension. This study was addressed to investigate the extent of extracardiac target organ damage (TOD) in patients with LV concentric remodelling. Two groups of never-treated essential hypertensives, 31 with normal LV geometry (group I, relative wall thickness: 0.39) and 31 with LV concentric remodelling (group II, relative wall thickness: 0.47) matched for age, sex, body mass index and mean 24-h systolic blood pressure (BP), were included in the study. They underwent clinical and laboratory examination, 24-h ambulatory BP monitoring (ABPM), 24-h urinary collection for microalbuminuria, non-mydriatic photography of ocular fundi, echocardiography and carotid ultrasonography. In both groups age (I: 51 +/- 11 years; II: 51 +/- 11 years), body mass index (I: 25 +/- 3 kg/m(2); II: 26 +/- 3 kg/m(2)), clinic and 24-h ABPM values (I: 149 +/- 11/95 +/- 8, 142 +/- 11/91 +/- 7 mm Hg; II: 150 +/- 11/98 +/- 9, 142 +/- 12/92 +/- 9 mm Hg) were similar by design. There were no differences between patients with normal LV geometry and with LV concentric remodelling in LVM index (97 +/- 16 vs 99 +/- 16), carotid intima-media thickness (0.7 +/- 0.02 vs 0.7 +/- 0.02) and carotid plaques prevalence (35% vs 35%). Furthermore, no significant differences among the two groups were found in the prevalence of retinal changes and microalbuminuria. These results suggest that in hypertensive patients with similar BP and LVMI levels, LV concentric remodelling is not associated with more prominent TOD.     

Twenty-four-hour heart rate and blood pressure are additive markers of left ventricular mass in hypertensive subjects

BACKGROUND: We investigated whether mean heart rate (HR(24)) and blood pressure (BP) parameters during 24-h ambulatory BP monitoring (ABP) are independent or additive markers of left ventricular (LV) mass in subjects with newly diagnosed, untreated hypertension. METHODS: A total of 250 patients (40% women, 60% men; mean age 59.6 +/- 11 years) with essential hypertension who were attending the outpatient Hypertension Unit were studied. All patients underwent 24-h ABP and HR monitoring as well as echocardiography for assessment of left ventricular (LV) dimensions and function. RESULTS: A decreasing HR24 or increasing ABP parameters (ie, systolic, diastolic, mean BP, and pulse pressure) were associated with increasing LV mass (P < .001) and wall thickness (P < .01). In multivariate analysis, after adjusting for age, gender, body surface area, body mass index, hematocrit, glucose, cholesterol, smoking, and each of the measured ABP parameters separately, decreasing HR24 was independently related to increasing LV mass in addition to ABP and body size parameters (P < .001). The addition of HR24 in different multivariate models for prediction of LV mass significantly increased the adjusted model r2 (range of r2 change: 0.039 to 0.064, P for change <.05). Decreasing HR24 or HR during daytime (6 am to 10 pm) was associated with a higher likelihood of LV hypertrophy in addition to ABP parameters (adjusted odds ratio 0.92 (CI 0.87 to 0.98), per 1 beat/min greater HR24 P = .002 and 0.93 (CI: 0.87 to 0.98), per 1 beat/min greater HR in the daytime P = .017). CONCLUSION: The 24-h HR and BP during ABP are independent and additive markers of increased LV mass in untreated hypertensive individuals.     

Microalbuminuria as a marker of preclinical diastolic dysfunction in never-treated essential hypertensives

Using 24-h ambulatory blood pressure (BP) monitoring and digitized M-mode echocardiography, we evaluated whether microalbuminuria is related to preclinical left ventricular (LV) diastolic dysfunction in hypertensive patients. We selected 87 never-treated hypertensive patients (mean 24-h BP > 140 and/or > 90 mm Hg); albuminuria was evaluated as mean value of 24-h urinary albumin excretion (UAE) from two 24-h urine collections. Microalbuminuria was found in 28 patients, classified as MA+ (UAE 30 to 300 mg/24 h); 59 patients had normal UAE (< 30 mg/24 h) and were classified as MA−. The MA+ and MA− groups did not differ with regard to age, sex, body mass index, or 24-h heart rate, whereas 24-h, daytime, and nighttime systolic and diastolic BP were significantly higher in MA+ than in MA−. The LV mass index was greater in MA+, as was the prevalence of LV hypertrophy; peak shortening rate of LV diameter, index of systolic function, was normal in all, but was lower in MA+. Peak lengthening rate of LV diameter and peak thinning rate of posterior wall, indices of diastolic function, were lower in MA+ and the prevalence of diastolic dysfunction was higher in MA+. UAE was inversely correlated with both indices of LV diastolic function, also after correction for age, 24-h heart rate, 24-h BP, and LV mass. In conclusion, in never-treated hypertensive patients, microalbuminuria is not only associated with greater myocardial mass, but is also related with preclinical impairment of LV diastolic function. This relation, independent from increased BP or LV mass, strengthens the role of microalbuminuria as an early and reliable marker of preclinical cardiac involvement.     

Prevalence of target organ damage in treated hypertensive patients: different impact of clinic and ambulatory blood pressure control

OBJECTIVES: First, to evaluate the prevalence of left ventricular (LV) hypertrophy, LV concentric remodelling and microalbuminuria in a selected sample of treated hypertensive patients with effective and prolonged clinic blood pressure (BP) control (BP < 140/90 mmHg). Second, to compare the prevalence of these markers of organ damage in patients with and without ambulatory BP (ABP) control, defined as average daytime BP < 132/85 mmHg). DESIGN AND METHODS: Fifty-eight consecutive hypertensive patients who attended our hypertension outpatient clinic over a period of 3 months and were regularly followed up by the same medical team were included in the study. Obesity, diabetes mellitus, history or signs of cardiovascular or renal complications and major noncardiovascular diseases were the exclusion criteria from the study. Each patient underwent 24 h ABP monitoring, echocardiography and 24 h urine collection for albumin measurement. RESULTS: The prevalence of LV hypertrophy (LV mass index > 125 g/m2 in both sexes), LV concentric remodelling (relative wall thickness > 0.45) and microalbuminuria (urinary albumin excretion < 300 mg/ 24 h) in this selected group of patients (32 men, 26 women; mean age 53 +/- 9 years; mean clinic BP 122 +/- 9/ 78 +/- 6 mmHg) was markedly low (6.9, 8.6 and 5.1%, respectively). The 26 patients with effective ABP control (group I) were similar to the 32 patients without effective ABP control (group II) in age, gender, body surface area, clinic BP, smoking habit, glucose, cholesterol and creatinine plasma levels. Prevalence of LV hypertrophy, LV concentric remodelling and microalbuminuria was lower in group I than in group II (0 versus 12.9% P< 0.01, 7.7 versus 9.4% NS, 3.8 versus 6.2% NS, respectively). CONCLUSIONS: This study demonstrates that nonobese, nondiabetic hypertensive patients with an effective clinic BP control have a very low prevalence of target organ damage and that LVH is present only in individuals with insufficient ABP control.     

Nurse-recorded clinic and ambulatory blood pressures correlate equally well with left ventricular mass and carotid intima-media thickness

OBJECTIVE: To assess relationships between noninvasive ambulatory blood pressure (BP), clinic BP (mean value of three readings in the seated position measured by nurses), structural cardiac indices, intima-media thickness of the common carotid artery and several hormones. DESIGN: Cross-sectional study of 75 subjects with hypertension and left ventricular hypertrophy (HTH) according to echocardiography, 35 subjects with hypertension and normal left ventricular dimensions (HT) and 23 normotensive subjects (NT). RESULTS: We found an excellent correlation between mean 24-h ambulatory BP and clinic BP, the r-value for systolic BP being 0.82 and for diastolic levels 0.78 (both P < 0.0001). Clinic and ambulatory BP correlated equally well with left ventricular (LV) mass index (r-values between 0.55 and 0.64, all P < 0.0001) and to intima-media thickness of the carotid artery (r = 0.18-0.34, P < 0.01). The systolic white-coat effect (clinic BP - day-time BP) was higher in the HTH and HT compared with NT and was weakly correlated to LV mass index (r = 0.18, P = 0.04). Nondippers (mean arterial night/day BP ratio of > 0.9) had higher brain (6.1 +/- 7.5 pmol L(-1) vs. 3.7 +/- 3.2 pmol L(-1), P = 0.01) and atrial (14 +/- 3.4 pmol L(-1) vs. 9.3 +/- 5.4 pmol L(-1), P = 0.04) natriuretic peptide levels, and also exhibited a lower ejection fraction (49 +/- 8% vs. 57 +/- 9%, P = 0.006), than dippers. CONCLUSION: Clinic BP recordings performed by nurses as three measurements 1 min apart provide excellent relationship to target organ damage. Nondippers exhibited signs of a more advanced hypertensive organ damage than dippers which corresponds well with the poor prognosis linked to this condition.     

Myocardial imaging with 123I-metaiodobenzylguanidine in essential hypertension and renovascular hypertension

Iodine-123 metaiodobenzylguanidine (MIBG) myocardial imaging is considered to reflect cardiac sympathetic function. We performed myocardial MIBG scintigraphy and echocardiography in 27 patients with essential hypertension (EHT), 7 patients with renovascular hypertension (RVHT), and 8 normotensive subjects (NT) to investigate alterations in MIBG myocardial imaging in the presence of hypertension and left ventricular hypertrophy (LVH). EHT were divided into two groups based on LV wall thickness; EHT with LVH group (> or = 13 mm, n = 15) and EHT without LVH group (< 13 mm, n = 12). The delayed uptake of MIBG was decreased, and the washout rate of MIBG was greater in the EHT with LVH group than EHT without LVH group or NT group. The washout rate was correlated with LV mass and LV diastolic function (as assessed by mitral flow). In RVHT group, the MIBG washout rate increased even without LVH, compared with NT and EHT without LVH groups. In summary, the washout rate of MIBG increased in parallel with the development of LVH in EHT and increased independently of the LV mass in RVHT. Cardiac sympathetic function could be altered in hypertensive LVH and in renovascular hypertension.     

Long-term cardiac effects of adrenalectomy or mineralocorticoid antagonists in patients with primary aldosteronism

Exposure to excess aldosterone results in cardiac damage in hypertensive states. We evaluated the long-term cardiac structural and functional evolution in patients with primary aldosteronism after surgical or medical treatment. Fifty-four patients with primary aldosteronism were enrolled in a prospective study and were followed for a mean of 6.4 years after treatment with adrenalectomy (n=24) or spironolactone (n=30). At baseline, echocardiographic measurements of patients with primary aldosteronism were compared with those of 274 patients with essential hypertension. Patients with primary aldosteronism had greater left ventricular mass, more prevalent left ventricular hypertrophy, lower early:late-wave diastolic filling velocities ratio, and longer deceleration time than patients with essential hypertension but no differences in relative wall thickness and systolic function. During follow-up, average blood pressure was 135/82 and 137/82 mm Hg in patients treated with adrenalectomy and spironolactone, respectively. In the initial 1-year period, left ventricular mass decreased significantly only in adrenalectomized patients. Subsequent changes in left ventricular mass were greater in patients treated with spironolactone, with an overall change from baseline to the end of follow-up that was comparable in the 2 groups. Prevalence of hypertrophy decreased in both treatment groups, whereas diastolic parameters had only mild and nonsignificant improvement. Changes in blood pressure and pretreatment plasma aldosterone were independent predictors of left ventricular mass decrease in both treatment groups. Thus, in the long-term, both adrenalectomy and spironolactone are effective in reducing left ventricular mass in patients with primary aldosteronism, with effects that are partially independent of blood pressure changes.     

Relation of ambulatory blood pressure load with left ventricular geometry in untreated patients with mild-to-moderate hypertension.

Whether ambulatory blood pressure (ABP) load is associated with left ventricular (LV) geometry was assessed in 335 patients (range 32-72 years) with stage I-II essential hypertension by performing 24-h ABP monitoring and echocardiographic examination. Of these 335 hypertensive subjects, 116 (34.5%) had normal LV geometry, 136 (40.5%) had concentric LV remodelling, 37 (11%) had eccentric LV hypertrophy and 46 (14%) had concentric LV hypertrophy according to the relative wall thickness and left ventricular mass index. Subjects with concentric LV hypertrophy had significantly increased 24-h systolic BP (SBP), diastolic BP (DBP) and mean arterial pressure as well as increased 24-h SBP and DBP load compared to those with normal LV geometry or concentric LV remodelling while there was no difference in the above parameters in comparison with the subjects with eccentric LV hypertrophy. The incidence of patients with normal LV geometry was significantly decreasing and the incidence of patients with LV-CH was significantly increasing as the degree of ABP loads were increasing. Using multiple regression analysis models with each type of LV geometry as a dependent variable and various degree of ABP loads as independent variables, it was revealed that normal LV geometry was significantly related with normal values of 24-h SBP and DBP load (P < 0.05) while there was not any significant relation between concentric LV remodelling and 24-h SBP or DBP load values. Concentric LV hypertrophy was significantly related with increased values of both 24-h SBP and DBP load (P < 0.05) while eccentric LV hypertrophy was significantly related with increased values of 24-h DBP load only (P < 0.05). In conclusion normal LV geometry is associated with normal values of SBP and DBP load while concentric LV hypertrophy is associated with increased values of both SBP and DBP load.     

24-h Ambulatory blood pressure in patients with ECG-determined left ventricular hypertrophy: left ventricular geometry and urinary albumin excretion-a LIFE substudy

This study was undertaken to evaluate the relationships among left ventricular (LV) geometric patterns and urinary albumin excretion in patients with hypertension and electrocardiographic (ECG) LV hypertrophy. In 143 patients with stage II-III hypertension, 24-h ambulatory blood pressure (BP) monitoring, single urine albumin determination, and echocardiography were performed after 14 days of placebo treatment. Mean age was 68+/-7 years, 35% were women, body mass index was 28+/-5 kg/m(2), LV mass index (LVMI) was 125+/-26 g/m(2), and 24% had microalbuminuria. The mean office BP was 176+/-15/99+/-8 mmHg and the mean daytime ambulatory BP was 161+/-18/92+/-12 mmHg. Ambulatory BP, but not office BP, was higher among albuminuric compared to normoalbuminuric patients. In patients with established hypertension, daytime pulse pressure and office BP were different in the four patterns of LV geometry, with the highest pressure in those with abnormal geometry. Furthermore, microalbuminuria was more frequent in hypertensive patients with LV hypertrophy than in those with either normal geometry or concentric remodelling. White coat hypertensives (10%) showed lower LVMI and no microalbuminuria compared to patients with established hypertension. There were no differences in the prevalence of nondippers (26%) among the four LV geometric patterns or in microalbuminuria. In conclusion, increased daytime pulse pressure and office BP were associated with increased prevalence of abnormal LV geometry. Microalbuminuria was more frequent in groups with concentric and eccentric LV hypertrophy. Ambulatory BP, but not office BP, was higher in albuminuric than normoalbuminuric patients. With regard to the relationship among BP, LV geometric patterns, and urine albumin excretion in this population, 24-h ambulatory BP did not provide additional information beyond the office BP.