Relationship between ambulatory and exercise blood pressure and cardiac structure

Isolated diastolic hypertension and target organ damage: Findings from the STANISLAS cohort

BACKGROUND

Isolated diastolic hypertension (IDH) is defined as diastolic blood pressure (DBP) ≥80 mmHg and systolic blood pressure (SBP) <130 mmHg according to 2017 ACC/AHA guidelines. The effective cardiovascular risk linked to IDH is debated.

HYPOTHESIS

IDH might contribute marginally to hypertension-related target organ damage (TOD) development.

METHODS

In this cross-sectional analysis 1605 subjects from the STANISLAS cohort, a large familiar longitudinal study from Eastern France, were included. Participants were categorized according to average values at 24-h ABP recording as having normal BP (SBP < 130/DBP < 80 mmHg); combined hypertension (SBP ≥130/DBP ≥80 mmHg or on antihypertensive treatment); IDH (SBP <130/DBP >80 mmHg); isolated systolic hypertension (ISH: SBP ≥130/DBP <80 mmHg). The association between hypertension status and TOD was assessed by multivariable-adjusted logistic models.

RESULTS

Using normotension as reference, IDH was not significantly associated with NTproBNP levels (adjusted odds ratio [OR] 1.04 [95%CI 0.82;1.32], p = .750), microalbuminuria (OR 0.99 [0.69; 1.42], p = .960), diastolic dysfunction (OR 1.53 [0.88; 2.68], p = .130), left ventricular (LV) mass index (OR per 10 g/m2 increase 1.07 [0.95; 1.21], p = .250), LV longitudinal strain (global: OR 1.07 [0.99; 1.14], p = .054; subendocardial: OR 1.06 [0.99; 1.13], p = .087), carotid intima media thickness (OR 1.27 [0.79; 2.06], p = .320), reduced ankle-brachial index (<0.9; OR 1.59 [0.19; 13.55], p = .670) and pulse wave velocity (PWV; OR 1.07 [0.93; 1.23], p = .360). In contrast, combined hypertension and ISH were independently associated with LV mass index and PWV increase (all p ≤ .01).

CONCLUSIONS

IDH was not significantly associated with TOD. Further studies are needed to clarify the clinical role of IDH. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01391442.

Impact of exaggerated blood pressure response in normotensive individuals on future hypertension and prognosis: Systematic review according to PRISMA guideline

PURPOSE

Arterial hypertension (aHT) is the leading risk factor for morbidity and mortality worldwide. Blood pressure (BP) deviation at rest is well defined and accompanies risk for cardiovascular events and cardiovascular mortality. A growing body of evidence emphasises that an exaggerated blood pressure response (EBPR) in cardiopulmonary exercise testing (CPET) could help to identify seemingly cardiovascular healthy and normotensive subjects, who have an increased risk of developing aHT and cardiovascular events in the future.

MATERIALS AND METHODS

The PubMed online database was searched for published studies reporting exercise-related BP and both the risk of aHT and cardiovascular events in the future.

RESULTS

We identified 18 original studies about EBPR in CPET, which included a total of 35,151 normotensive individuals for prediction of new onset of aHT in the future and 11 original studies with 43,012 enrolled subjects with the endpoint of cardiovascular events in the future. Although an EBPR under CPET is not well defined, a large number of studies emphasise that EBPR in CPET is associated with both new-onset aHT and cardiovascular events in the future.

CONCLUSIONS

A growing number of studies support the hypothesis that EBPR in CPET may be a diagnostic tool to identify subjects with an elevated risk of developing aHT and cardiovascular events in the future.

Ambulatory blood pressure monitoring: what a pediatrician should know

PURPOSE OF REVIEW

Ambulatory blood pressure monitoring is a useful tool for the evaluation and management of hypertension in children and adolescents. This review provides a basic overview of ambulatory blood pressure monitoring and summarizes the most recent available knowledge regarding its use in the pediatric population.

RECENT FINDINGS

Evaluation and validation of ambulatory blood pressure monitoring equipment in children remains limited, although advances in the interpretation of results for this age group have been reported specifically in the area of circadian (24 h) and ultradian (<24 h) variability. Blood pressure is a dynamic phenomenon that varies not only with time but also with changing patient and environmental circumstances. Growing evidence regarding conditions identified when this variability is considered, specifically white coat and masked hypertension, suggests that office blood pressure measurement may not be a sufficient screening test for hypertension-related target-organ damage.

SUMMARY

Information regarding ambulatory blood pressure monitoring use in children is increasing, although due to its limitations and expense, it remains a tool primarily utilized by the pediatric sub-specialist.

Enhanced antinatriuresis in response to angiotensin II in essential hypertension

Angiotensin II regulates sodium homeostasis by modulating aldosterone secretion, renal vascular response, and tubular sodium reabsorption. We hypothesized that the antinatriuretic response to angiotensin II is enhanced in human essential hypertension. We therefore studied 48 white men with essential hypertension (defined by ambulatory blood pressure measurement) and 72 normotensive white control persons, and measured mean arterial pressure, sodium excretion, renal plasma flow, glomerular filtration rate, and aldosterone secretion in response to angiotensin II infusion (0.5 and 3.0 ng/kg/min). Hypertensive subjects exhibited a greater increase of mean arterial pressure (16.7+/-8.2 mm Hg v 13.4+/-7.1 mm Hg in normotensives, P < .05) and a greater decrease of renal plasma flow (-151.5+/-73.9 mL/ min v -112.6+/-68.0 mL/min in controls, P < .01) when 3.0 ng/kg/min angiotensin II was infused. The increase of glomerular filtration rate and serum aldosterone concentration was similar in both groups. Sodium excretion in response to 3.0 ng/kg/min angiotensin II was diminished in both groups (P < .01). However, the decrease in sodium excretion was more pronounced in hypertensives than in normotensives (-0.18+/-0.2 mmol/min v -0.09+/-0.2 mmol/min, P < .05), even if baseline mean arterial pressure and body mass index were taken into account (P < .05). We conclude that increased sodium retention in response to angiotensin II exists in subjects with essential hypertension, which is unrelated to changes in glomerular filtration rate and aldosterone concentration. Our data suggest a hyperresponsiveness to angiotensin II in essential hypertension that could lead to increased sodium retention.

Elevated ambulatory blood pressure in 20 subjects with Williams syndrome

Previous studies report conflicting frequencies of hypertension in cohorts of patients with Williams syndrome (WS). We studied blood pressure (BP) in WS using 24-hour ambulatory BP monitoring. This technique reliably measures day- and nighttime BP in a subject's natural environment and provides better prognostic information on long-term risks of hypertension than casual BP determinations. Twenty WS subjects evaluated through a multidisciplinary WS clinic and 35 age and gender-matched controls were studied. We found that WS subjects had significantly higher ambulatory BP than controls. After controlling for age, sex, and weight, the diagnosis of WS added approximately 10 mmHg to mean daytime and nighttime BPs. Hypertension, as defined by elevated mean daytime BP, was present in 40% of WS subjects versus 14% of controls (P < 0.05); among the children studied this difference was even more dramatic with 46% of WS children versus 6% of control children classified as hypertensive (P = 0.01). We also demonstrated normal diurnal BP variation but no evidence of a "white coat" effect or increased BP variability. Interestingly, parental reporting of a history of infantile hypercalcemia was strongly associated with the presence of hypertension (P = 0.008). Our data demonstrate that both children and adults with WS have higher mean BP and higher frequency of hypertension than healthy controls. Thus, elevated BP readings in the office setting should not be dismissed but require more thorough assessment.

Office and laboratory blood pressures as predictors of daily blood pressure level in normotensive subjects and borderline and mild hypertensive subjects

A series of standardized laboratory tests [10 min sitting and supine, 9 min standing, dynamic; cycle ergometer (ERG) and isometric exercise; handgrip (HG)] were performed during intra-arterial blood pressure (BP) recording in 97 healthy unmedicated men, initially classified as normotensive (NT, n = 34), borderline hypertensive (BHT, n = 29) or mildly hypertensive (HT, n = 34) by repeated office blood pressure (OBP) measurements. After testing, a 24-h intra-arterial ambulatory BP (IABP) recording was obtained while subjects performed their normal activities. Day and night periods were analysed as well as 24-h averages for systolic BP (SBP) and diastolic BP (DBP) using Pearson correlations and multiple linear regressions. In normotensive subjects, the supine SBP predicted IABP measurements best (r range 0.39-0.69, P < 0.05-0.001). In multiple regression, supine SBP explained 49% of 24-h SBP variance (F = 12.4, P = 0.001). For BHT, supine SBP was also the best predictor (r range 0.09-0.64, P NS to P < 0.001), and it explained 37% of 24-h SBP variance (F = 15.6, P = 0.0005). In HT, ERG DBP correlated best with IABP (r range 0.52-0.75, P < 0.01-0.001). ERG SBP explained 49% of 24-h SBP (F = 31.0, P = 0.0000) and ERG DBP explained 56% of 24-h DBP (F = 35.4, P = 0.0000) variance. Laboratory BP correlations were generally better with day than with night measurements. OSBP correlated moderately well with IABP in NT, and weakly in BHT and HT; ODBP instead correlated with IABP in NT and HT but not significantly in BHT. In conclusion, OBP is less closely related to IABP than laboratory BP, but even laboratory BP generally explains less than 50% of IABP variance. Stressors such as exercise are useful only in HT. For BHT, the prediction of IABP with laboratory measures was even weaker than in other groups, and thus ambulatory measurements cannot be replaced by short-duration laboratory measurements and stress tests.

Safe withdrawal of monotherapy for hypertension is poorly effective and not likely to reduce health-care costs

OBJECTIVE

To carry out a population-based evaluation of withdrawal of treatment in primary care using repeated ambulatory blood pressure monitoring (ABPM) assessment to avoid subjecting patients to prolonged periods of excess risk.

METHOD

Patients from two community practices (total population 11 034 patients) being administered monotherapy for hypertension, were identified and invited to participate. Subjects were withdrawn from treatment if they had no significant co-morbidity and daytime ABPM blood pressure was < or = 150/90 mmHg. Antihypertensive therapy was restarted if daytime ABPM blood pressure was > 150/90 mmHg during weeks 4, 8, 12, 26, 39 and 52.

RESULTS

Of 126 eligible patients 53 had a co-morbidity and 37 declined to participate. Of the 36 patients who entered the study 10 were excluded because they had elevated ABPM blood pressures during treatment and one because they had echocardiographic left ventricular hypertrophy. Of the 25 patients from whom monotherapy was withdrawn, we restarted treatment of 19 before week 52. If clinic blood pressure monitoring had been used instead of ABPM, different decisions would have been taken in eight of 25 cases. The costs of the ABPM-determined withdrawal of treatment programme were greater than the expected savings in drug costs, even assuming that all six patients from whom treatment was withdrawn remained without treatment for a further 9 years. This conclusion was not sensitive to reducing the number of ABPM measurements and to inflation in study-drug costs. However, if all patients had been treated with the most expensive drug, then even the full ABPM programme could have saved money within 9 years.

CONCLUSIONS

Antihypertensive therapy could be withdrawn from only a small proportion of patients in the community on the basis of ABPM. The costs of the programme are likely to exceed savings unless the cost of drugs administered is substantially higher than that observed in this study.

Blood pressure level and variability in the prediction of blood pressure after 5-year follow-up

We compared mean intra-arterial ambulatory blood pressure (IAMB), blood pressure (BP) diurnal profiles are variability, and postural measurements with casual sphygmomanometric measurements for the prediction of future BP. We studied 97 healthy, ummedicated men classified as normotensive (NT, n = 34), borderline hypertensive (BHT, n = 29), or mildly hypertensive (HT, n = 34) by repeated casual measurements during the 2 months before IAMB. Five years later, we reassessed 79 subjects (81%) using casual BP measurements and noninvasive ambulatory 24-hour BP monitoring (NAMB). IAMB level generally correlated well with follow-up BP and slightly better with NAMB level than with casual measurements (24-hour IAMB versus follow-up NAMB systolic BP [SBP], r = .64, P < .001; versus diastolic' BP [DBP], r = .52, P < .001). NT and BHT subgroup correlations were of similar strength, but the relationship in the HT subgroup was not significant. Similarly, when we examined daytime and nighttime BP levels, nighttime BP correlated better with follow-up BP in NT and BHT but not in HT. The only measures that were significantly related to follow-up BP in HT were two BP variability measures, SD and the range of variability (RV80: 90th minus 10th percentile), (initial 24-hour IAMB SD and follow-up BP, r = .42 to r = .52, P < .05 to P < .01; RV80 versus follow-up BP, r = .43 to r = .52, P < .05 to P < .01). Correlations of follow-up BP with postural BP were generally weaker than with casual BP or IAMB level. Linear stepwise regressions for SBP and DBP separately (including all IAMB variables) demonstrated that the best single predictor for follow-up BP was 24-hour IAMB SBP level, which explained 41% of follow-up NAMB SBP level variance (F = 52.6, P < .001). However, in a second analysis including casual values, casual SBP alone explained 44% of follow-up NAMB SBP variance (F = 62.5, P < .001), whereas IAMB SBP added only 4% (F = 5.5, P < .05). Predictions of follow-up DBP were always poorer. After 5 years, 70% of NT and 86% of HT were still in their initial classification group, but 67% of BHT had become hypertensive. In these new HT (n = 16), initial IAMB level correlated most strongly with follow-up NAMB level (24-hour SBP, r = .70, P < .01; 24-hour DBP, r = .55, P < .05). The only other significant demographic variable predicting future BP was change in weight over 5 years, which added 10% to the explanation of future casual SBP variance (F = 12.5, P = .0007) and 15% to casual DBP variance (F = 18.0, P = .0001); for NAMB, the percentages were lower. In logistic regression, those NT and BHT who became hypertensive (n = 22) had a 75% probability of becoming hypertensive if they gained 11.7 kg or more during 5 years (X2 = 4.5, P = .03). To conclude, BP tended to increase in all groups, especially in BHT, during follow-up. Nominal differences were observed between casual measurements and BP level measures in the prediction of future BP, and their explanatory value for future BP was generally less than 50%. However, for BHT who became hypertensive, BP level and variability measurements somewhat improved the prediction of follow-up BP. Weight gain was an important additional predictor for future hypertension in both NT and BHT.

Ambulatory blood pressure reproducibility and application of the method in a healthy Finnish cohort

The aim of the present study has been to study the reproducibility, validity and normal values of ambulatory blood pressure measurement in a healthy Finnish cohort. The reproducibility of ambulatory blood pressure monitoring was examined in healthy volunteers and normal values were determined in a Finnish cohort of males and women of different ages. In the reproducibility study the recording was repeated at 2-week intervals. In the validity study simultaneous measurements were done manually with a mercury sphygmomanometer and compared with the measurement by the ambulatory blood pressure recording unit, both connected with the cuff by a T-tube; this study included 100 consecutive measurements in a patient group. A relatively small cohort was taken from the normal value study group. In addition to ambulatory blood pressure their left ventricle mass was also determined by echocardiography. The correlation between manual blood pressure measurement and simultaneous measurement by the ambulatory blood pressure unit was 0.98. In the reproducibility study the correlations between the two 24-h measurements 2 weeks apart were also good. Depending on the parameter (daytime, nighttime or 24-h blood pressure mean, systolic or diastolic values) the correlation coefficient varied between 0.81 and 0.91. Thus both systolic and diastolic blood pressures, whether expressed as 24-h averages and daytime or nighttime averages, correlated well between these two recording sessions. The data obtained in the present Finnish cohort were well within the published reference value limits, showing only fairly modest age-dependence appearing at quite an old age. There was no significant correlation between the left ventricle mass and ambulatory blood pressure values in a population having normal blood pressure. The results suggest good intra-individual correlation and reproducibility in ambulatory blood pressure monitoring, suggesting this method to be useful in the monitoring of individual blood pressure levels. The validity of the method is good and the published reference values can be applied with reasonable reliability in different populations. In an adult population with normal blood pressure, no correlation between left ventricle mass and blood pressure values can be found, suggesting this correlation may first appear in cohorts including persons with elevated blood pressure values.

Comparison of the 10-minute supine-30-minute tilt test with 24-hour ambulatory blood pressure for the diagnosis of diastolic systemic hypertension

A variant of the protracted tilt test, the 10-minute supine -30-minute tilt test (10S-30TT), has been proposed by us for the evaluation of blood pressure (BP). The present investigation compares parameters of diastolic BP by 3 methods: office measurements, 10S-30TT, and 24-hour ambulatory monitoring; the last method served as a reference standard. Twenty patients presenting at the office with diastolic BP values ranging from 80 to 120 mm Hg (median 90) were studied. Statistically significant correlations were observed between the following parameters: diastolic office BP and average ambulatory awake diastolic BP (r = 0.64, p = 0.002); average tilt-test diastolic BP and average ambulatory awake diastolic BP (r = 0.69, p = 0.0006); frequency of elevated diastolic BP values during the tilt test and frequency of elevated ambulatory awake diastolic BP values (r = 0.69, p = 0.0007). Diastolic BP diagnosis scores exhibited strong correlation only between the ambulatory and tilt-test diagnosis (kappa = 0.70), but not between ambulatory and office BP diagnosis (kappa = 0.50). Based on the close correlation between results of the 10S-30TT and ambulatory monitoring in the evaluation of diastolic BP, we suggest that the faster and cheaper tilt test may serve as a substitute in certain categories of patients.

Left ventricular morphology and diastolic function in uraemia: echocardiographic evidence of a specific cardiomyopathy

OBJECTIVE

To see whether cardiac morphological and functional abnormalities in uraemic patients are determined by high blood pressure or if they are an expression of a specific cardiomyopathy.

DESIGN

Cross sectional study.

SETTING

City general hospital in Italy.

SUBJECTS

35 uraemic patients receiving haemodialysis (17 men, 18 women; mean age 60.3 (11.2); mean duration of dialysis 52 months) were selected from the 64 patients in Venice who were receiving dialysis; subjects with diabetes, haemochromatosis, valvar dysfunction, regional dyskinesias, and pericarditis were excluded. 19 control normotensive subjects (6 men and 13 women), matched for age.

MAIN OUTCOME MEASURES

Echocardiographic measurements of left atrium, left ventricular end diastolic and end systolic volume, aortic root diameter, posterior wall and interventricular septum thickness, left ventricle mass index, and ejection fraction in controls and in patients according to whether they were normotensive (five men, eight women) or hypertensive (12 men, 10 women) on 48 hour ambulatory monitoring; left ventricular diastolic function by Doppler ultrasonography.

RESULTS

Mean systolic and diastolic pressures, daytime systolic and diastolic pressures, and night time systolic and diastolic pressures were significantly higher in the hypertensive patients than in the normotensive patients. The normotensive patients had similar blood pressures to the controls. Left ventricular mass correlated significantly with the mean diastolic pressure and mean night time systolic and diastolic pressures. Parathyroid hormone concentrations were similar in the two groups of patients. Diastolic relaxation was impaired to the same degree in the two groups of patients. Parameters of diastolic function showed no relation to left ventricular mass, which was significantly higher in the hypertensive than in the normotensive patients.

CONCLUSIONS

Uraemia is likely to induce specific changes in the relaxation properties of the myocardium. These changes are responsible for the impaired diastolic function independently of blood pressure, degree of hypertrophy, and metabolic changes, which suggests the existence of a specific cardiomyopathy. Hypertension remains a determinant of left ventricular mass.

Ambulatory blood pressure monitoring in paediatric patients treated by regular haemodialysis and peritoneal dialysis

Ambulatory blood pressure monitoring (ABPM) has been shown to be more representative of blood pressure (BP) levels than casual BP measurements in adult patients treated by haemodialysis (HD). In this study we compared ABPM using the oscillometric SpaceLabs 90207 monitor with casual BP measurements in 35 paediatric patients [17 treated by peritoneal dialysis (PD) and 18 by HD]. Heart rate and plasma concentrations of atrial natriuretic peptide were also measured. No correlations were found between ABPM and causal BP measurements, except for systolic day-time BP in PD patients (r = 0.63). Seventy percent of PD and 33% of HD patients were regarded as hypertensive when evaluated by ABPM, while casual BP measurements demonstrated hypertension in 47% (P < 0.05) of PD patients and in 44% (NS) of HD patients. One-third of patients were reclassified by ABPM either from normotensive to hypertensive (7/19) or from hypertensive to normotensive (5/16). BP assessed by ABPM was higher in PD than in HD patients. The physiological decline of BP at night was significant and more pronounced in PD than in HD patients. In HD patients day-time BP did not differ between the 1st and the 2nd interdialytic day, but increased in the night hours before the following dialysis session. A positive correlation was found between day-time BP and pre-dialysis plasma atrial natriuretic peptide in both treatment groups. In conclusion this study demonstrates that casual BP recordings are not representative of average BP in dialysed paediatric patients. ABPM is useful in the diagnosis and treatment of hypertension in children with end-stage renal disease.

Influence of isolated diastolic hypertension identified by ambulatory blood pressure on target organ damage

Clinical decisions and controlled studies in regard to hypertension have long emphasized the casual diastolic blood pressure (DBP). The influence of superimposition of high systolic blood pressure (SBP) on the target organ damage has been less studied. To assess the role of isolated diastolic hypertension without interference of superimposition of systolic hypertension, 171 subjects with normal blood pressure, isolated diastolic hypertension (SBP < 140 and DBP > or = 90 mmHg) isolated systolic hypertension (SBP > or = 140 and DBP < 90 mmHg) or combined hypertension (SBP > or = 140 and DBP > or = 90 mmHg) determined by mean 24-h ambulatory blood pressure were compared in relation to target organ damage including ECG abnormality related to hypertension, cardiac enlargement by chest X-ray, proteinuria and retinopathy. The incidence of target organ damage was lower in subjects with normal BP than in the other three groups. The incidence of target organ damage was almost significantly higher in patients with isolated systolic hypertension than in those with isolated diastolic hypertension. No significant difference in the incidence of complications existed between patients with isolated systolic and combined hypertension. These findings demonstrate that the severity of hypertensive complications is more closely related to mean ambulatory SBP than mean ambulatory DBP. The level of systolic BP is important for predicting the severity of target organ damage in patients with high diastolic BP, because there is a significant difference in the incidence of target organ damage between isolated diastolic hypertension and combined hypertension.

Left ventricular mass estimation by echocardiography: is it clinically useful?

Echocardiographic determination of left ventricular mass provides prognostic information that is independent of blood pressure. This prognostic information has a graded and continuous relationship with outcome, and is independent of traditional risk factors. This article addresses the prognostic and clinical utility of echocardiography for detection of left ventricular mass. Recommendations will be offered regarding the use of echocardiography for screening in select individuals.

24 hour blood pressure monitoring in healthy and hypertensive children

24 Hour ambulatory blood pressure monitoring (ABPM) was performed to provide data on the normal daily blood pressure of healthy schoolchildren and on patients with hypertension. The subjects studied were 123 healthy schoolchildren with a mean (SD) age of 12.5 (1.6) years (range 9.5-14.5 years), 24 children with borderline or mild hypertension, 17 with renal hypertension and normal renal function, 10 with chronic renal failure, and six with a renal allograft. In eight children with definite renal disease a second measurement was performed after treatment modification. The monitor used for ABPM was validated with a mercury column manometer. The mean (SD) of the signed differences of the blood pressure measured by the two methods was -0.19 (1.75) mmHg for the systolic and -0.21 (2.11) mmHg for the diastolic blood pressure (n = 60). Normal values for daytime and night time blood pressure were determined for those aged 10-14 years. The mean (SD) blood pressure of the 123 children was 109 (7)/66 (8) mmHg (systolic/diastolic) for the daytime and 96 (8)/52 (7) mmHg at night time. Of the 24 children with borderline or mild hypertension 14 had a raised blood pressure on ABPM. The circadian rhythm was disturbed in three children of this group. Even children with normal daytime blood pressure had significantly higher systolic blood pressure in the night when compared with the controls. The incidence of disturbed circadian rhythm was higher in the groups with renal hypertension (4/17 in the subgroup with normal renal function, 5/16 in the group with renal failure and/or transplantation). All children undergoing a second ABPM measurement had a lower average blood pressure after treatment adjustment. ABPM measurements were reproducible and accurate. The method provided new data on the physiological circadian variation of blood pressure in healthy children. It proved to be a helpful tool in the diagnosis of hypertension, particularly in the detection of cases of disturbance of the circadian rhythm of blood pressure pattern and individual adjustment of treatment.

Is white coat hypertension innocent? Structure and function of the heart in the elderly

To evaluate the morphological and functional characteristics of the heart in elderly patients with white coat hypertension, we performed an echocardiographic study in 67 elderly individuals older than 60 years: 17 patients with white coat hypertension, 34 patients with true hypertension, and 16 normotensive control subjects. White coat hypertension was defined as a mean 24-hour ambulatory systolic blood pressure of less than 140 mm Hg associated with office hypertension. Cardiac responses to an isometric handgrip exercise test were used to evaluate left ventricular functional reserve. Left atrial dimension and left ventricular mass index were significantly greater in the white coat hypertension group than in the normotension group (P < .05) but were similar to values in the true hypertension group. Left ventricular diastolic function, expressed by peak late-early filling ratio of diastolic mitral flow, showed increasing impairment in the order of the normotension, white coat hypertension, and true hypertension groups (analysis of variance, P < .05); the ratio in the white coat hypertension group tended to be higher than that in the normotension group (unpaired t test, P = .054). The relation between fractional shortening and end-systolic stress did not shift downward after handgrip exercise in the white coat hypertension group, indicating that functional reserve in the left ventricle was maintained. Thus, patients with white coat hypertension had a moderately increased left atrial dimension and left ventricular mass in association with a tendency for disturbed diastolic function, although systolic functional reserve remained the same. These findings suggest that white coat hypertension in the elderly may not be innocent.

Thermal biofeedback treatment of mild hypertension. A comparison of effects on conventional and ambulatory blood pressure measures

Several studies have produced results suggesting that thermal biofeedback treatment is effective in lowering the blood pressure (BP) of individuals with both mild and moderate essential hypertension. This study used thermal biofeedback to treat 9 unmedicated individuals with mild hypertension. Subjects underwent 24-hour ambulatory BP monitoring both prior to and following the thermal biofeedback treatment regimen. Four of the subjects were considered treatment successes using standard office blood pressure assessments as the success-fail criteria. However, 24-hour ambulatory BP measures showed a markedly different pattern of results, with several subjects who were considered successes under conventional assessment techniques showing an increase in 24-hour ambulatory BP from pre- to posttreatment. There was a significant decrease in diastolic blood pressure for all subjects as measured by the ambulatory method. There was also a significant decrease in systolic and diastolic standing home blood pressure. The implications of these results are discussed.

Diminished nocturnal decline in blood pressure in elderly hypertensive patients with left ventricular hypertrophy

To assess the circadian blood pressure (BP) changes in elderly hypertensive patients with left ventricular hypertrophy (LVH), the ambulatory BP was measured noninvasively every 30 minutes for 24 hours in those patients with LVH (n = 15) and without LVH (n = 23), and in normotensive elderly subjects (n = 11). Although the daytime systolic BP (SBP) was comparable in the two hypertensive groups, the nighttime SBP in patients with LVH tended to be higher than in patients without LVH (149.0 +/- 15.1 versus 138.4 +/- 20.1 mm Hg, p less than 0.10). The LV mass index correlated significantly with the nighttime SBP (r = 0.43, p less than 0.01), but not with the daytime SBP (r = 0.24, ns), with clinic SBP (r = 0.14, p = ns) or the SBP after handgrip exercise (r = 0.31, p = ns). The difference in the systolic BP between daytime and nighttime (D-N SBP) in patients with LVH (2.8 +/- 9.4 mm Hg) was significantly less than that in patients without LVH (12.8 +/- 16.0 mm Hg) (p less than 0.02). In addition, the D-N SBP correlated inversely with the left ventricular mass index (r = -0.33, p less than 0.05). It was concluded that hypertension in the elderly with LVH was associated with a diminished nocturnal decline in blood pressure.

Once vs twice daily administration of a fixed combination of captopril plus hydrochlorothiazide in essential hypertension: a double-blind crossover study in known responders to a standard combination

The purpose of this randomized, double-blind, crossover trial was to compare the hypotensive effects of a fixed combination of captopril (C) 50 mg and hydrochlorothiazide (HCTZ) 25 mg (C 50/HCTZ 25) once daily with those of a fixed combination of C 25 mg and HCTZ 12.5 mg (C 25/HCTZ 12.5) twice daily. We studied 199 patients (108 M, 91 F) with mild to moderate essential hypertension whose BP was already controlled by the co-administration of C 25 mg and HCTZ 12.5 mg twice daily. They were randomly assigned to either C 25/HCTZ 12.5 twice daily during the first 6 weeks and C 50/HCTZ 25 once daily during the second 6 weeks or C 50/HCTZ 25 once daily followed by C 25/HCTZ 12.5 twice daily. Both regimens showed comparable efficacy on office diastolic BP (91.6 vs 91.3 mm Hg). Systolic BP was slightly but significantly higher (P = 0.02) with the once daily formulation (141.2 vs 139.1 mm Hg). Fixed combinations once daily and twice daily resulted in identical working ambulatory BP (133.7 +/- 13/83.6 +/- 8 mm Hg vs 132.4 +/- 11/83.3 +/- 7 mm Hg) without affecting heart rate. Adverse events were reported by 16% of patients and cough was the most common occurring in 7%. In conclusion, these results indicate that the fixed combination of C 50/HCTZ 25 given once daily controls office and working BP as well as the fixed combination C 25/HCTZ 12.5 given twice daily in patients with mild to moderate hypertension.

Efficacy of 24-hour ambulatory blood pressure monitoring in children

OBJECTIVES

To determine whether the use of an ambulatory blood pressure monitor (ABPM) is feasible and gives accurate readings in children, and to provide data on normal daily blood pressures (BPs) and BP patterns in children.

DESIGN

Cohort.

SUBJECTS

Ninety-nine healthy fifth-grade students.

INTERVENTIONS

Students wore an ABPM for 24 hours while recording their activities in diaries. Before and after the study period, each subject had three BPs simultaneously measured with the ABPM and a mercury manometer to assess the accuracy of the ABPM. An activity scale was retrospectively applied to diary entries to help explain the variety of BP patterns noted during data analysis.

RESULTS

Systolic BPs obtained with the ABPM at the beginning and end of the study were slightly higher than those obtained with a mercury manometer; diastolic BPs were virtually identical. A circadian pattern of BPs was noted: mean systolic and diastolic BPs were higher during the day than at night. The BP patterns ranged from "hypoactive" (little baseline variation) to "hyperactive" (wide fluctuations with spikes to elevated BP ranges) during various activities. In general, higher BPs were noted at times of increased activity or emotional levels.

CONCLUSIONS

Ambulatory BP monitoring was well tolerated, and measurements were reproducible and accurate. The variety of BP measurements noted at different activity levels indicate that a child's activity should be considered during data analysis. As further experience is gained, the ABPM should prove helpful in diagnosis and management of hypertension in children.

Circadian blood pressure pattern in patients with treated hypertension and left ventricular hypertrophy

Left ventricular hypertrophy in hypertensives is an important determinant of prognosis. In the present study 45 patients with treated essential hypertension were divided into two groups: 23 patients had normal left ventricular dimension and 22 patients had echocardiographic signs of left ventricular hypertrophy (LVH). All patients were adequately treated during daytime, but ambulatory blood pressure monitoring showed a distinct abnormal pattern in the LVH group characterized by a lack of blood pressure reduction during the night; 16 of 22 patients with LVH had no blood pressure decline during the night, whereas 17 of 23 patients without hypertrophy showed this reduction (P less than 0.01). In conclusion, patients with hypertension and LVH often reveal a lack of blood pressure decline during the night, which may be the reason for the development of left ventricular hypertrophy (and thus should be managed by a different circadian blood pressure therapy) or which may be the consequence of progressive structural changes in the resistance vessels, along with the development of left ventricular hypertrophy. It is suggested that patients with hypertension and left ventricular hypertrophy should have ambulatory twenty-four hour blood pressure monitoring.

Elevated pulmonary artery pressure. An independent predictor of mortality

Analyses in this study were based on hemodynamic and angiographic data obtained in a cohort of 1,371 predominantly black patients during right and left heart catheterization. All patients were followed up prospectively for a mean of 117 weeks, and 103 fatal events were recorded. In Cox survival analysis, three variables were found to be independently related to survival: pulmonary artery mean pressure (PAMP), number of stenosed vessels, and left ventricular (LV) ejection fraction (p less than 0.01); in multivariate stepwise analysis, PAMP entered the model first with the largest chi 2 value of the three prognostic variables (chi 2 = 33.4; p less than 0.0001). The PAMP was 32 percent higher in decedents compared with survivors (25 + 11 mm Hg vs 19 + 8 mm Hg, p less than 0.01 [mean, SD]) and a 10 mm Hg increase in PAMP was associated with a more than fourfold increase in the relative risk of dying; this finding was independent of pulmonary vascular resistance and therefore could not be attributed to primary pulmonary vascular or parenchymal disease. In both the subgroup of 1,118 patients with a normal LV ejection fraction (greater than 50 percent) and the 253 patients with a reduced ejection fraction (less than 50 percent), PAMP emerged as an independent predictor of mortality (p less than 0.0001 and 0.01, respectively), and is therefore a marker of cardiac disease beyond impairment of systolic contractile function. Among patients without obstructive coronary artery disease, PAMP alone provided prognostic information in the multivariate survival analysis.

Effect of 24-hour blood pressure and heart rate variations on left ventricular hypertrophy and dilatation in essential hypertension

This study correlates variables derived from blood pressure (BP) and heart rate (HR) monitoring with the degree of left ventricular structural changes in essential hypertension. Forty patients with mild-to-moderate hypertension according to World Health Organization criteria underwent 24-hour ambulatory monitoring. Echocardiographic (posterior wall and interventricular septum thickness, left ventricular mass) or ECG (SV1 + RV5) indices of hypertrophy were significantly (p less than 0.01) correlated (positive correlations) with derivatives of BP monitoring (mean systolic and diastolic BP values) but not with HR derivatives. Echocardiographic indices of dilatation (left ventricular end-diastolic volume and diameter) were significantly (p less than 0.01 to less than 0.001) correlated (negative correlations) with derivatives of HR monitoring (mean HR values, mainly during the night) but not with BP derivatives. It is concluded that in essential hypertension, left ventricular hypertrophy depends on mean 24-hour systolic and diastolic BP values, whereas left ventricular dilatation appears to be more prominent in patients with bradycardia mainly during the night.