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We compared the antihypertensive effects of the beta-blocker atenolol and the converting enzyme inhibitor lisinopril during 12 weeks of treatment in patients with mild to moderate essential hypertension. Atenolol (n = 10) significantly decreased conventionally measured blood pressure from 144/103 to 135/93 mm Hg and lisinopril (n = 9) from 150/104 to 130/92 mm Hg. Based on data derived from automated 24-h ambulatory blood pressure monitoring, atenolol decreased the average whole-day systolic pressure by 18 +/- 6 mm Hg (p less than 0.02) and the diastolic pressure by 11 +/- 2 mm Hg (p less than 0.01). Lisinopril produced decreases of 27 +/- 5 mm Hg (p less than 0.01) and 13 +/- 2 mm Hg (p less than 0.001). Examination of the 24-h blood pressure patterns showed that the efficacies of the two drugs were similar. Each appeared to be effective throughout the whole-day monitoring period, although only lisinopril significantly decreased blood pressure during the final four-h period (4 AM to 8 AM) preceding the next day's dose. Neither drug produced significant echocardiographic changes in left ventricular wall thickness or muscle mass during the short-term treatment. Lisinopril and atenolol effectively decrease blood pressure during a 24-h period. Moreover, we found that automated whole-day blood pressure monitoring is a useful tool for comparing the efficacy and duration of action of differing antihypertensive agents.

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We have evaluated the accuracy of measurements provided by different types of portable automatic blood pressure monitoring devices by comparing them with intra-arterial and mercury sphygmomanometer measurements in 25 hospitalized patients. Systolic blood pressure values with portable devices that use auscultatory or oscillometric methods of measurement correlated significantly with intra-arterial values (r = 0.74 and 0.89; p less than 0.001 for both); similarly, diastolic values correlated significantly (r = 0.86 and 0.81; p less than 0.001 for both). Compared with intra-arterial measurements, there was a slight tendency for the portable devices to underestimate systolic blood pressure and overestimate diastolic blood pressure. Correlations between auscultatory or oscillometric measurements and sphygmomanometer measurements in these patients were also significant; moreover, the absolute blood pressure values obtained with the portable devices were almost identical to those with the sphymomanometer. In a further group of 12 volunteers, auscultatory and oscillometric values correlated very closely with simultaneously measured sphygmomanometer values for both systolic (r = 0.99 and 0.98) and diastolic (r = 0.96 and 0.94) blood pressures. An auscultatory device that uses continuous ECG R wave gating for Korotkoff sounds was also found to be highly accurate. Thus we have found that automated portable devices that use either auscultatory or oscillometric methods of measurement provide reliable blood pressure values.

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Whole-day ambulatory monitoring is used for diagnosing hypertension and for judging response to treatment. We evaluated both of these properties in an antihypertensive trial with the calcium channel blocker diltiazem hydrochloride. Measured by a conventional sphygmomanometer, systolic and diastolic blood pressures fell significantly in patients who received diltiazem, whereas no consistent changes occurred in those who received placebo. Administration of the drug also decreased systolic and diastolic blood pressures evenly throughout the day, as determined by automated monitoring. The 15 diltiazem-treated patients were subdivided into those whose clinically diagnosed hypertension was confirmed by pretreatment blood pressure monitoring (24-hour average diastolic blood pressure, greater than or equal to 90 mm Hg; n = 9) and those whose 24-hour blood pressures failed to meet this criterion (n = 6). Diltiazem therapy decreased average whole-day blood pressures by 18/13 mm Hg in the hypertensives but by only 0/1 mm Hg in the others. Thus, whole-day blood pressure monitoring strengthens antihypertensive trials by documenting efficacy and duration of treatment. In addition, it enhances the diagnosis of hypertension, thereby identifying those patients in whom treatment seems justified.

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To evaluate body weight as a determinant of cardiac structure and function in adolescents, 47 normotensive 13-year-old subjects were studied with M-mode echo duplex Doppler echocardiography (DE). They were separated by body weight into standard (greater than 55 kg) and lighter (less than 55 kg) groups. No subject had a blood pressure greater than 140/90. The differences between the groups in systolic (SBP) and diastolic (DBP) blood pressures, LV mass, left atrial size (LA), and peak aortic flow velocity (PAoV) were measured. (Formula: see text). Body weight strongly correlated with SBP in the entire study group (r = 0.66, P less than 0.001) but slightly less strongly with DBP (r = 0.48, P less than 0.001). Left ventricular filling indices such as peak early diastolic flow velocity, early diastolic filling integral, peak atrial flow velocity, and atrial filling integral were not significantly different between the groups. No significant differences in blood pressure, LV mass, LA size, or peak aortic flow velocity could be demonstrated when the subjects were subdivided on the basis of gender or presence or absence of family history of hypertension. Body weight appeared to be not only a strong predictor of blood pressure but also of cardiac structural and functional characteristics in adolescents.

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Results of clinical and experimental studies suggest that extrarenal actions of corticosteroid hormones must be involved in the overall effects of these steroids on the circulation. A dissociation between levels of mineralocorticoids and sodium balance or renal effects of steroid hormones is often observed in patients with primary or secondary forms of hypertension. Receptors for various steroids have been found in the peripheral circulation. Stimulation of these receptors probably leads to changes in the electrolyte content of the cell. In turn, these changes have a direct or indirect effect on the contractility of the vascular wall. The physiological importance of the vascular effects of steroids in human hypertension remains to be elucidated.

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Self-adhesive patches containing a 7-day supply of transdermal clonidine were used to treat twenty patients with mild essential hypertension. These skin patches (3.5 cm2), which were changed by the patients every week, reduced diastolic blood-pressure to less than 90 mm Hg in twelve patients. When placebo-containing patches were substituted in these twelve patients after 3 months of treatment, blood-pressure rose slowly to its pretreatment level. Side effects appeared to be milder than those experienced during conventional oral antihypertensive treatment. Plasma clonidine concentrations were lower than peak levels after oral administration. This new method for treating hypertension was convenient and well tolerated, and may increase patient compliance.

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M-mode echocardiography was used in 12 patients with essential hypertension to study changes in cardiac anatomy during long-term therapy with hydrochlorothiazide (50 to 100 mg) and alpha-methyldopa (500 to 1,750 mg). Echocardiographic examination was performed after six weeks of treatment with hydrochlorothiazide alone and after four to six weeks, six months, and nine months of treatment with both hydrochlorothiazide and alpha-methyldopa. Hydrochlorothiazide alone induced a small, and not significant, change in blood pressure (from 157 +/- 16 (SD)/105 +/- 9 to 150 +/- 14/101 +/- 5 mm Hg). Changes in echocardiographic parameters of cardiac anatomy were not observed during short-term diuretic therapy. Addition of alpha-methyldopa further reduced blood pressure (to 133 +/- 11/90 +/- 6 mm Hg, p less than 0.001), which was maintained throughout the study. Gradual decreases in diastolic septal thickness (from 10.9 +/- 1.1 to 9.5 +/- 1.0 mm, p less than 0.01), relative wall thickness (from 0.40 +/- 0.06 to 0.36 +/- 0.06, p less than 0.05) and left ventricular cross-sectional area (from 18.9 +/- 2.9 to 17.3 +/- 2.6 cm2, p less than 0.05) were observed. Posterior wall thickness did not change significantly during the study. The results provide evidence for regression of echocardiographic parameters of cardiac muscle mass during long-term antihypertensive treatment with a diuretic and a centrally-acting sympatholytic drug. Regression of left ventricular mass was not clearly related to changes in casual blood pressure. However, patients who showed a decrease in septal thickness tended to have a greater decrease in systolic blood pressure than those in whom septal thickness did not change during therapy. Moreover, patients in whom a decrease in left ventricular transverse dimension was observed, had a greater decrease in both systolic and diastolic blood pressure than those in whom left ventricular diastolic dimension did not change.

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Trimazosin was given for periods of at least 6 mo to 25 patients with mild to moderate essential hypertension. In doses of 300 to 900 mg dialy trimazosin alone led to blood pressure control (supine diastolic blood pressure less than 90 mm Hg with a fall of at least 10 mm Hg) in 16 patients (64%). Despite the decrements in blood pressure there were no changes in body weight or creatinine clearance. There was also no changes in plasma renin activity or urinary aldosterone excretion rate. Although patients with high control renin values appeared to have greater blood pressure decreases than those with low renin values, responsiveness to treatment was not associated with consistent effects of trimazosin on the renin-angiotensin system. Trimazosin induced a small decrease in plasma total cholesterol concentration. In seven patients whose blood pressures were not controlled by trimazosin alone, the addition of polythiazide led to decreased blood pressure and in five control of pressure was achieved. Thus, trimazosin is an effective antihypertensive when given by itself or in combination with a diuretic. Its mechanism of action has not been established, but its ability to induce vasodilation without concomitant sodium retention or stimulation of the renin axis may be an important factor in its effectiveness.

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