Beta-adrenergic receptor blockade as a therapeutic approach for suppressing the renin-angiotensin-aldosterone system in normotensive and hypertensive subjects.

Although beta-adrenergic-blocking drugs suppress the renin system (RAAS), plasma angiotensin II (Ang II) responses during beta-blockade have not been defined. This study quantifies the effects of beta-blockade on the RAAS and examines its impact on prorenin processing by measuring changes in the ratio of plasma renin activity (PRA) to total renin. In normotensive (N = 14) and hypertensive (N = 16) subjects, blood pressure (BP), heart rate, PRA, plasma prorenin, plasma total renin (prorenin + PRA), ratio of PRA to total renin (%PRA), plasma Ang II, and urinary aldosterone were measured before and after 1 week of beta-blockade.

Relations of ambulatory blood pressure level and variability to left ventricular and arterial function and to left ventricular mass in normotensive and hypertensive adults.

OBJECTIVE: To assess the relationships between the level and variability of ambulatory blood pressure and left ventricular and arterial function. METHOD: We related 24 h ambulatory systolic blood pressure (SBP) and diastolic blood pressure (DBP), measures of their variability and clinic blood pressures to echocardiographic measures of left ventricle geometry and systolic function, total peripheral resistance, and the pulse pressure: stroke volume ratio as a measure of arterial stiffness in 58 normotensive and 222 unmedicated hypertensive adults. RESULTS: For hypertensive patients and for the entire population, awake and home ambulatory as well as technician-measured DBP were negatively related to left ventricle midwall fractional shortening (MWS) and to MWS as a percentage of the value predicted for end-systolic stress (afterload-corrected MWS), with inconsistent relations with SBP.

Blood Pressure Monitoring begins its second year.

This issue of Blood Pressure Monitoring introduces our second year of publishing research papers devoted to original investigation in the discipliners of blood pressure measurement and variability. In this foreword, we would like tio take the opportunity to review some of the achievements from our first year of the Journal and briefly describe our plans for the future.

White-coat hypertension and sex.

OBJECTIVES: To compare, by sex, selected behavioral and biologic characteristics among normotensive, white-coat hypertensive, and essential hypertensive patients, and to assess the similarities and differences in these characteristics between men and women diagnosed as having white-coat hypertension. METHODS: The subjects of this study were 764 men (80 normotensives, 112 white-coat hypertensives, and 572 essential hypertensives) and 442 women (53 normotensives, 81 white-coat hypertensives and 308 essential hypertensives) who were a nonrandom subset of a larger cohort of patients being assessed to determine the prognostic significance of ambulatory blood pressure measurements. Physician-measured technician-measured and ambulatory (average awake and asleep) blood pressures, daytime blood pressure variability, the difference between awake and sleeping blood pressures, cholesterol levels, plasma renin activity (PRA) and anthropometric and demographic characteristics were compared across the patient classifications within each sex group and between male and female white-coat hypertensives using one-way analysis of variance.

Variability of blood pressure.

INTRODUCTION: The justification for ambulatory blood pressure monitoring is that blood pressure varies, and a better understanding of the causes of such vqariability will greatly improve our knowledge of its consequences. Although it is generally assumed that the average or true level of blood pressure is the main culprit causing vascular damage, it would be surprising if the variability did not also contribute. Variability of blood pressure is a compoex issue, and is the result of internal and external influences acting in various combinations.

Assessment of arterial compliance by carotid midwall strain-stress relation in hypertension.

To elucidate the relations between arterial hypertrophy and compliance in hypertension, we studied 205 unmedicated hypertensive patients (129 men and 76 women) and 82 normotensive adults (56 men and 26 women) from an employed population by carotid ultrasound, noninvasive applanation tonometry, and echocardiography. Carotid midwall strain and circumferential stress were calculated at end diastole and peak systole. The relations of luminal and midwall strain to the increment in circumferential stress from end diastole to peak systole (Deltacarotid stress in normal subjects) were used to calculate ratios of observed/predicted carotid luminal and midwall strain.

Assessment of arterial compliance by carotid midwall strain-stress relation in normotensive adults.

Examining left ventricular midwall as opposed to endocardial mechanics enhances understanding of left ventricular function in individuals with abnormal cardiac geometry. Accordingly, we used carotid ultrasound and applanation tonometry of arterial pressure to derive carotid midwall strain and its relation to carotid peak-systolic and end-diastolic stresses in 82 apparently normal, employed subjects (56 men, 26 women; median age, 47 years; 70% white; 21% overweight) with no evidence of coronary or valvular heart disease. Regression equations relating carotid luminal and midwall strain to the increment in carotid stress during systole (Deltacarotid stress) were used to predict strain for the observed Deltastress.

Prevention of recurrent pulmonary edema in patients with bilateral renovascular disease through renal artery stent placement.

Pulmonary edema and congestive heart failure (both referred to here as PE) have been reported to be complications of bilateral renal artery stenosis or unilateral stenosis in a solitary functioning kidney (both referred to as BRAS). The goals of this study were to determine whether a history of PE was more common in patients with BRAS than in those with unilateral stenosis and a normal contralateral kidney (URAS), and whether recurrent PE could be prevented by renal artery stent placement. We evaluated 90 consecutive patients with renovascular disease who were treated with percutaneous renal artery stent placement.

A longitudinal study of job strain and ambulatory blood pressure: results from a three-year follow-up.

Objective: This study was conducted to investigate the hypothesis that exposure to "job strain" is related to increased ambulatory blood pressure (ABP).

Method: Participants were 195 men who wore an ABP monitor for 24 hours on two occasions 3 years apart. Job strain status, evaluated at each assessment, was used to identify four groups: those not having job strain at either assessment (N = 138), those having job strain at both times (N = 15), and two crossover groups.

Impact of shift work and race/ethnicity on the diurnal rhythm of blood pressure and catecholamines.

To evaluate the effects of shift work and race/ethnicity on the diurnal rhythm of blood pressure and urinary catecholamine excretion of healthy female nurses, 37 African American women and 62 women of other races underwent ambulatory blood pressure monitor and urine collection for 24 hours that included a full work shift: day shift (n=61), evening shift (n=11), and night shift (n=27). Awake and sleep times were evaluated from subjects' diaries. Of African Americans, 79% who were working evenings or nights and 32% working day shifts were nondippers (<10% drop in systolic pressure during sleep), whereas only 29% of others working evening+night and 8% working day shifts were nondippers.

Relation of age to left ventricular function in clinically normal adults.

The extent to which age, independent of cardiovascular diseases, influences left ventricular (LV) function in adults is uncertain. Echocardiograms and simultaneous arterial pressure in 464 clinically normal adults aged 16 to 88 years were used to measure LV dimensions, endocardial and midwall LV fractional shortening, stroke volume, cardiac output, and circumferential end-systolic stress. The ratios of observed endocardial and midwall shortening to values predicted for observed end-systolic stress were used as measures of chamber and myocardial function.

Differential effects of angiotensin converting enzyme inhibition and diuretic therapy on reductions in ambulatory blood pressure, left ventricular mass, and vascular hypertrophy.

Diuretic-based therapy is less effective in reducing the cardiac complications of hypertension than the risk of stroke and may be less effective in reducing left ventricular (LV) mass than is therapy with angiotensin converting enzyme (ACE) inhibition. In view of the strong association of LV hypertrophy with cardiovascular risk, this study was designed to compare the impact of therapy with a diuretic and ACE inhibition on cardiac and vascular structure. Fifty essential hypertensives (74% male, 88% nonwhite) participated in a double-blind study for 6 months and were randomized to either ramipril or hydrochlorothiazide (HCTZ).

Time-voltage QRS area of the 12-lead electrocardiogram: detection of left ventricular hypertrophy.

Identification of left ventricular hypertrophy (LVH) using 12-lead ECG criteria based primarily on QRS amplitudes has been limited by poor sensitivity at acceptable levels of specificity. Because the product of QRS voltage and duration, as an approximation of the time-voltage area of the QRS complex, can improve accuracy of the 12-lead ECG for LVH, we examined the diagnostic value of true time-voltage area measurements of QRS complexes from the standard 12-lead ECG. Standard 12-lead ECGs and echocardiograms were obtained in 175 control subjects without LVH and in 74 patients with regurgitant valvular heart disease and LVH defined by echocardiographic criteria (indexed LV mass >110 g/m2 in women and >125 g/m2 in men).

Relation of left ventricular midwall function to cardiovascular risk factors and arterial structure and function.

Left ventricular (LV) midwall shortening (MWS) is subnormal in relation to LV circumferential end-systolic stress (ESS) (ESS-corrected MWS) in many hypertensive patients with normal LV chamber function and predicts subsequent morbidity and mortality. However, little is known of the relations of LV midwall function to demographic and metabolic variables or to arterial geometry. Asymptomatic, unmedicated normotensive (n=366) or hypertensive (n=282) adults were assessed with echocardiography and carotid ultrasound.

The generalizability of cardiovascular responses across settings.

The generalizability of cardiovascular reactivity change scores remains largely unsupported. In previous studies, several factors differed between laboratory and field, making poor lab-to-life correlations difficult to interpret. The present study varied only one parameter between the lab and field: setting.

Prospective study of simultaneous orthoiodohippurate and diethylenetriaminepentaacetic acid captopril renography. The Einstein/Cornell Collaborative Hypertension Group.

Unlabelled: Captopril renography (CR) has been established in the past 10 yr as a useful diagnostic test for renovascular hypertension. However, direct comparison of tubular and glomerular tracers, quantitative criteria, comparison of quantitative and qualitative results and the reliability of the results in renal failure have not been described in a systematic, prospective fashion.

Methods: Same-day baseline and CR using 99mTc-labeled diethylenetriaminepentaacetic acid (DTPA) and [131I]orthoiodohippurate (OIH) were simultaneously performed in two groups of hypertensive subjects, one with demographically defined essential hypertension (n = 43) and the other (n = 60) with a high prevalence of renovascular disease, defined with angiograms.

Job strain and health behaviors: results of a prospective study.

Purpose: To assess the association between job demands, job decision latitude, and job strain (defined by Karasek as a combination of high demands and low decision latitude) and cardiovascular disease-related health behaviors such as cigarette smoking, alcohol use, lack of exercise, and overweight.

Design: Cross-sectional and prospective.

Setting: Nine New York City public and private sector worksites.