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To determine the presence of cardiac disease in hypertensive patients with disparities between physician and out-of-office blood pressures, we prospectively studied three groups of age-matched patients identified by both casual (office) and ambulatory blood pressures: (1) office blood pressure greater than 140/90 mm Hg and awake ambulatory blood pressure of 130/80 mm Hg or less ("office" hypertensives); (2) office blood pressure less than 135/85 mm Hg and awake ambulatory blood pressure of 130/80 mm Hg or less (normotensives); and (3) office blood pressure greater than 140/90 mm Hg and awake ambulatory blood pressure of 140/90 mm Hg or greater ("daytime" hypertensives). In the patients with office hypertension, both the left atrial index and left ventricular mass index were significantly less than in patients with daytime hypertension and not statistically different from those of the normotensive subjects. Left ventricular filling rate at rest and ejection fraction at peak exercise were significantly greater in the office hypertensive group than in the daytime hypertensive group but were no different from those of the normotensive subjects. These findings demonstrate that patients with blood pressure elevation only in the physician's office have cardiac size and function similar to those of normotensive individuals. Thus, the average daily blood pressure best predicts cardiac end-organ damage. [ABSTRACT FROM AUTHOR]

To determine the magnitude and the relationships of the difference between office and awake ambulatory blood pressures (BP) (white-coat effect) in ambulatory hypertensive patients, 64 consecutive patients referred to the ambulatory BP monitoring laboratory were studied. All subjects were evaluated prospectively by study nurse, study doctor, and ambulatory BP measurements. Order of measurements was randomized and observers were blinded to each others readings. No differences were found in the white-coat effects among study nurse (22/14 +/- 20/9 mm Hg), study doctor (27/12 +/- 20/10 mm Hg) and referring doctor (19/11 +/- 18/10 mm Hg). Similarly, female and male patients exhibited similar white-coat effects on the day of ambulatory monitoring. Older patients (> or = 65 years) displayed higher mean systolic white-coat effects than younger patients (29 +/- 18 mm Hg vs 19 +/- 19 mm Hg, P = 0.04). Multivariate analysis using the mean average systolic white-coat effect as the dependent variable and age, gender, treatment status, body mass index (BMI) and duration of hypertension as independent variables showed a significant independent role for age. In contrast, no clinical correlates of the diastolic white-coat effect were found. Older patients are more likely to display a systolic white-coat effect in the medical care environment.

Objective: To compare the reproducibility of ambulatory and office blood pressure readings in established hypertensive subjects when studies are repeated at extended time intervals., Subjects: Twenty-five hypertensive patients (office diastolic blood pressure > or = 90 mmHg) who were off antihypertensive therapy for at least 4 weeks and had repeat office and ambulatory blood pressures at least 3 months apart under similar study conditions., Methods: On the same day, patients underwent office blood pressure readings measured by mercury column sphygmomanometry and then by ambulatory blood pressure monitoring. Ambulatory blood pressure monitoring was done for 24 h, and awake and sleep periods were divided according to a diary kept by each patient. A second study was performed in an identical manner at a mean +/- SD interval of 23 +/- 24 months (range 3-80, median 15). The agreement between studies was assessed by correlation coefficients, coefficients of variation and standard deviation of the differences (SDD)., Results: There were no significant differences in office, 24-h, awake and sleep mean blood pressures between the two studies. Mean 24-h systolic and diastolic blood pressures were 16 and 14 mmHg lower, respectively, than office blood pressure values. Correlation coefficients were significantly higher for 24-h ambulatory blood pressure than office blood pressure, whereas the SDD between visits was significantly lower for 24-h ambulatory blood pressure than office blood pressure., Conclusions: These data demonstrate that long-term reproducibility of ambulatory blood pressure is superior to that for office measurement. One implication of this finding is that, in long-term clinical pharmacology trials utilizing ambulatory blood pressure, fewer subjects would be required than for studies that used office blood pressure end-points.

To clinically evaluate the QuietTrak ambulatory blood pressure (BP) recorder (Tycos-Welch-Allyn, Arden, NC), we assessed the device according to the performance criteria set out by the 1992 Association for the Advancement of Medical Instrumentation (AAMI) guidelines. The QuietTrak is a portable, noninvasive recorder that uses an auscultatory measuring system. As recommended in the 1992 AAMI guidelines, a large, heterogeneous population was recruited for the study using three clinic sites to assess accuracy and clinical performance. In addition, observer agreement and the effects of age, arm circumference, heart rate, posture, and blood pressure level on the observer-device differences were analyzed. There were 1098 simultaneous, same arm BP measurements performed in 122 subjects by the QuietTrak recorder versus two skilled clinicians per site using a teaching stethoscope and 24-h blood pressure recordings performed in 46 subjects to assess reliability of the monitor. The differences in observers for all sites were 0.7/-0.5 +/- 3.8/3.5 mm Hg with 89% of the BPs within 5 mm Hg. The mean difference between observer average and the device (all positions) was 0.3/-1.5 +/- 5.0/7.5 mm Hg. The agreement between the QuietTrak and mercury column determinations was within 10 mm Hg for 92 to 94% of systolic readings and 91 to 93% of diastolic readings, depending on the posture. The limits of agreement (2 standard deviations about the mean difference) between observers and the device for systolic BP tended to be lower for the sitting position (-11 to 10 mm Hg) compared to supine (-14 to 13 mm Hg) and standing (-14 to 14 mm Hg) positions.(ABSTRACT TRUNCATED AT 250 WORDS)

Objective: To study the test-ordering behavior of practicing physicians regarding ambulatory monitoring of blood pressure and to assess changes in patient management after this study., Design: Cross-sectional assessment of physicians' practice habits regarding the ordering of ambulatory blood pressure monitoring and a longitudinal study of patient management after monitoring., Setting: Physicians' offices in central Connecticut., Participants: Two hundred thirty-seven consecutive patients referred by 65 community- and hospital-based physicians., Measurements: Indications for ambulatory blood pressure monitoring, changes in diagnosis and therapy, and office blood pressures before and after the ambulatory blood pressure study., Results: The main indications for ordering the test included borderline hypertension (27% of studies ordered), assessment of blood pressure control during drug therapy (25%), evaluation for "white coat" or "office" hypertension (22%), and drug-resistant hypertension (16%). After the ambulatory blood pressure study, only 13% of the patients had further testing (for example, echocardiography); the diagnosis was changed in 41% of the patients, and antihypertensive therapy was changed in 46%. In 122 patients for whom data were complete, office blood pressure measured by the referring physician decreased from 161/96 +/- 22/12 mm Hg before the ambulatory blood pressure study to 151/86 +/- 27/12 mm Hg 3 months after the study (P = 0.004 for systolic blood pressure and P < 0.001 for diastolic blood pressure). One to 2 years after the study, office blood pressure was 149/86 +/- 24/12 mm Hg (P > 0.2 compared with 3 months after the study). Seventy-two percent of the patients had a lower office blood pressure within 3 months of the ambulatory blood pressure study., Conclusions: Practicing physicians use ambulatory blood pressure recordings for appropriate indications, and data from the monitoring studies affected the management of patients with hypertension.

During the last decade, ambulatory blood pressure monitoring (ABPM) made a transition from a method reserved for clinical investigators to a technique considered useful by practicing physicians in assessing certain problems in hypertension. Recent recommendations of the National High Blood Pressure Education Program (NHBPEP) Working Group on Ambulatory Blood Pressure Monitoring suggested using ABPM for a number of clinical problems, including borderline hypertension without target organ damage, evaluation of drug resistance, and white-coat hypertension. We evaluated the clinical indications for ordering ABPM by Connecticut physicians both in hospital and community-based practices. Through specific questionnaires, the clinical indications used by referring physicians to order ABPM and their inclinations for future use of the methodology were assessed. Forty-seven of 70 physicians (65%) responded to the questionnaire, basing their answers on 237 patients. The majority of physicians were internists (57%) or cardiologists (25%). Leading indications for patient referral for ABPM included borderline hypertension (27%), assessment of drug therapy/BP control (25%), and possible white-coat hypertension (22%). Far fewer referrals were observed for severe hypertension or as a routine test for the diagnosis of hypertension. These data suggest that practicing physicians have become aware of the usefulness of ambulatory blood pressure recordings and are following the NHBPEP guidelines on referral for the study.

The A&D TM-2420 (A&D Engineering, Milpitas, CA) is an automatic, portable, noninvasive blood pressure (BP) recorder which uses a dual microphone system for the detection of Korotkoff sounds. Its accuracy and clinical performance were assessed in a multicenter study that also addressed issues such as observer agreement and the effects of age, arm circumference, heart rate, posture, and blood pressure level on the observer-device differences. We compared 906 simultaneous, same-arm BP measurements in 151 subjects using the TM-2420 versus two skilled clinicians per site using a teaching stethoscope. The agreement between the TM-2420 and mercury column determinations were within 10 mm Hg for 86 to 91% of systolic readings and 91 to 94% of diastolic readings, depending on the posture; a level of agreement which would receive a 'B+' grade from the recent British Hypertension Society guidelines. The limits of agreement (2 standard deviations about the mean difference) for systolic BP between observers and the TM-2420 tended to be greater for the standing position (-20 to 15 mm Hg) compared to supine (-14 to 12 mm Hg) and seated (-13 to 8 mm Hg) positions. Limits of agreement between the observers and device were not dependent upon age, heart rate, arm size, or blood pressure level. Twenty-four-hour blood pressure monitoring in two of the four centers demonstrated an error code rate of 3.4%, excluding 'retries' that are one of the device's features. These data demonstrate an acceptable level of accuracy and performance of the sixth generation of the TM-2420 for use in clinical practice and research.(ABSTRACT TRUNCATED AT 250 WORDS)

To assess the clinical efficacy of chronic nitrendipine therapy in mild to moderate essential hypertension, we studied blood pressure (BP) and heart rate responses in 22 subjects receiving maintenance nitrendipine therapy. Ten subjects (45%) whose hypertension was controlled with chronic monotherapy had an 11/12 mm Hg decrease in supine BP (P less than 0.05) with a mean (+/- SD) dose of 71 +/- 15 mg/day. The 12 (55%) subjects whose hypertension was not controlled with monotherapy had a comparatively higher baseline BP than the other 10 (156/105 +/- 10/6 compared with 150/98 +/- 15/4 mm Hg; P less than 0.05). Eight of the 10 subjects demonstrating office BP control with chronic nitrendipine monotherapy who also had full-time employment underwent continuous ambulatory BP monitoring before and after maintenance monotherapy. Nitrendipine induced a reduction in the mean 24-hour BP and mean BP at home, but did not reduce the BP during work or while asleep. These data suggest that nitrendipine lowers BP when assessed by casual office methods. The ambulatory BP monitor data demonstrate that the hypotensive response to chronic nitrendipine is modified during work periods, which are generally associated with increased adrenergic activity. Ambulatory BP monitoring may be superior to office (casual) monitoring in the assessment of the overall efficacy of antihypertensive drugs.

To determine the effects of dopamine-1 agonist therapy in severe hypertension, blood pressure, heart rate, catecholamines and left ventricular function were studied in 18 patients (10 with renal disease) with diastolic blood pressure greater than 120 mm Hg (range 124 to 160) after intravenous fenoldopam therapy. Constant infusions of fenoldopam were titrated upward every 10 to 20 min from an initial dose of 0.1 microgram/kg per min to a maximal dose of 0.9 microgram/kg per min. The therapeutic goal of a supine diastolic blood pressure of less than 110 mm Hg was achieved in every patient within 1 h at an average dose of 0.34 +/- 0.22 microgram/kg per min. Blood pressure decreased from 214/134 +/- 33/10 mm Hg at baseline to 170/96 +/- 29/7 mm Hg (p less than 0.0001) at 3 h, whereas heart rate increased from 77 +/- 23 to 88 +/- 21 beats/min (p less than 0.01). Plasma norepinephrine increased during the fenoldopam infusion; epinephrine and dopamine levels did not change. Two indexes of left ventricular function (end-systolic dimension and isovolumic relaxation time) improved during the fenoldopam infusion, but mitral flow velocities during ventricular filling were unchanged. Side effects of intravenous fenoldopam were mild, transient and associated with the marked vasodilatory properties of the drug. Thus, fenoldopam is safe and effective as a parenteral monotherapy in patients with severe essential and renovascular hypertension. Preliminary data suggest that blood pressure reduction with selective dopamine-1 agonist therapy is accompanied by improved left ventricular function.

We assessed blood pressure (BP) and heart rate (HR) responses in a double-blind, randomized study comparing cilazapril, a long-acting, nonsulfhydryl-group converting enzyme inhibitor, with placebo in 18 patients with mild to moderate (sitting diastolic BP, 95 to 114 mm Hg) essential hypertension. The BP and HR parameters were evaluated at rest (casual, 24 hours after administration), during treadmill exercise testing (Bruce protocol), and with 24-hour noninvasive ambulatory BP monitoring. These assessments were made after a 4-week drug washout period and after 8 to 12 weeks of therapy. After 8 weeks of therapy with cilazapril (mean dose 3.6 +/- 0.9 mg/day), casual BP decreased 19/11 mm Hg (p less than 0.01), whereas placebo lowered BP by 4/5 mm Hg (difference not significant) compared with the baseline period. The casual HR was modestly (7 beats/min) but significantly (p less than 0.05) lowered by cilazapril monotherapy. Exercise BP was reduced by cilazapril (reduction at peak HR, 23/11 +/- 10/5 mm Hg; p less than 0.05), and exercise HR was unchanged. Compared with baseline, the duration of exercise was improved with cilazapril but not with placebo (1.0 minute vs -0.2 minute; p less than 0.05). Twenty-four-hour mean, awake, and sleep BPs were reduced with cilazapril with the most impressive reduction occurring during the awake period (19/12 mm Hg; p less than 0.01). These data demonstrate that cilazapril lowers casual, exercise, and ambulatory BP with a modest but significant improvement in exercise time. Thus cilazapril may be particularly effective in the physically active hypertensive patient.

We studied blood pressure (BP) and heart rate (HR) responses in 12 patients with hypertension who were receiving cetamolol, a cardioselective beta-blocker with intrinsic sympathomimetic activity. The BP and HR parameters were evaluated at rest (casual, office readings), with ambulatory BP monitoring, and after treadmill exercise testing. At a mean (+/- SD) dose of 46 +/- 21 mg/day, casual supine BP decreased by 10/12 mm Hg (P less than 0.05 for systolic; P less than 0.01 for diastolic) compared with placebo, while HR decreased 4 bpm. Cetamolol resulted in a significant reduction in the mean 24-hour systolic BP. The most striking reduction occurred in the BP at work (23 mm Hg), with almost no decrease in the BP during sleep. Ambulatory HR reductions occurred while the subjects were at work (9 bpm; P less than 0.05) but not while at home (awake) or during sleep. The mean duration of exercise was the same during cetamolol and placebo phases, but both HR and BP fell significantly at peak performance after cetamolol. These data suggest that cetamolol reduces BP without lowering HR at rest. During periods of increased adrenergic activity such as work and dynamic exercise, both HR and BP are reduced.

We compared simultaneous, same-arm blood pressure (BPs) obtained with the Accutracker, an ambulatory blood pressure (BP) monitor, which uses R-wave gating for Korotkoff sounds to those of both a blinded, skilled clinician using a mercury column and a three-channel graphic display of cuff pressure tracings, Korotkoff sounds, and ECG tracing. Eighteen subjects, with a wide variety of BPs, heart rates, and ages, participated in the study. The systolic BP obtained by the ambulatory recorder, clinician, and the three-channel strip chart recorder were 132 +/- 23 mmHg, 132 +/- 24 mmHg, and 133 +/- 25 mmHg, (all NS), respectively. Accutracker recorder-determined systolic BP correlated highly both with the clinician and strip chart readings (r = 0.98 and 0.97, respectively; p less than 0.0001 for both). The diastolic BP obtained by the Accutracker recorder was slightly, but significantly, lower than the clinician's readings (76 +/- 12 mmHg vs. 81 +/- 13 mmHg; p less than 0.005) and similar to the strip chart recorder readings (76 +/- 12 mmHg vs. 77 +/- 12 mmHg; NS). In 32 young, healthy subjects with no activity restrictions, 91% of the raw BP data from 24-hour ambulatory recordings was acceptable using strict deletion criteria. These data demonstrate that the Accutracker is highly accurate compared with clinician-determined blood pressures. The lower diastolic BP readings may stem from the ability of this device to detect softer Korotkoff sounds than can be detected by the clinician. These findings should be taken into consideration when using ambulatory BP monitoring in clinical trials of antihypertensive drugs.