(Hypertension. 1997;29:1213-1217.)
© 1997 American Heart Association, Inc.
Articles |
Age-Related Changes in Total Arterial Capacitance From Birth to Maturity in a Normotensive Population
From the Division of Cardiology, The New York Hospital–Cornell Medical Center, New York (G. de S., M.J.R., R.B.D.); Department of Clinical and Experimental Medicine, Federico II University Hospital, Naples, Italy (G. de S., G.M., R.G.); and Children's Hospital Medical Center, Division of Cardiology, Department of Pediatrics, University of Cincinnati (Ohio) (S.R.D., T.R.K.).
Correspondence to Dr Giovanni de Simone, Division of Cardiology, The New York Hospital–Cornell Medical Center, 525 E 68th St, New York, NY 10021. E-mail mjograd{at}mail.med.cornell.edu
 |
Abstract |
|---|
 Top Abstract IntroductionMethodsResultsDiscussionReferences |
|---|
Abstract We evaluated the effect of body growth and aging on the ratio of echocardiographic (Teichholz) stroke volume to pulse pressure (SV/PP ratio) in 373 normal-weight, normotensive children to adolescents (1 day to 17 years old; 166 girls, 87 nonwhite) and 393 normal adults (17 to 85 years old; 164 women, 112 nonwhite). Stroke volume increased with age in children (r=.64, P<.0001) and was stable in adults; pulse pressure decreased slightly with age in children (r=-.10, P=.06) and increased in adults (r=.29, P<.0001). As a consequence, SV/PP ratio increased with age in children (r=.51, P<.0001) and decreased in adults (r=-.18, P=.0004). To control for changes in body size that influence the size of the arterial tree, we used ANCOVA to adjust SV/PP for body size. Body size–adjusted SV/PP ratio was no longer related to age in children, whereas the negative relation with aging in adults remained statistically significant (r=-.19, P<.0002). Heart rate was negatively related to SV/PP ratio in both children and adolescents and adults, but this relation did not influence the relation with age. In multivariate analysis, high SV/PP ratio was predicted by greater height (P<.002) and weight (P<.04) and nonwhite race (P<.001) in children and adolescents and by younger age (P<.0001), greater weight (P<.0001), and low heart rate (P<.001) in adults. Sex did not enter the regression models. Thus, (1) SV/PP ratio is a measure of increasing capacity of the arterial tree during growth, whereas it depends on arterial compliance during adulthood through old age; (2) arterial compliance decreases progressively with aging; (3) the apparent difference between males and females might be due to their different body sizes.
Key Words: age • compliance • body constitution • sex • stroke volume
|
Introduction |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
The capacity of the arterial tree to receive blood pumped with each heart beat is related both to its ability to distend for a given pressure and to its size. Thus, the increase in pulse pressure for a given stroke volume is directly related to vascular stiffness.1 The ratio between stroke volume and pulse pressure (SV/PP ratio) has been proposed as a crude measure of total arterial compliance.2 3
Arterial compliance is an important component of the resistance to ejection, of myocardial afterload, and of the consequent geometric modifications of the left ventricle.4 5 6 It has been demonstrated that arterial compliance decreases with aging in adults,7 8 but there is little information about the physiological evolution of arterial compliance during the different phases of human life from birth to old age in females and males. Accordingly, we designed this study to investigate the relation of the SV/PP ratio and its physiological meaning in an age span encompassing the entire human life.
|
Methods |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Seven hundred sixty-six normal-weight, normotensive individuals, aged 1 day to 85 years, were studied at three centers: 212 men and 138 women from a cohort of employed adults evaluated at the New York Hospital–Cornell Medical Center; 139 boys and 127 girls as part of a population-based epidemiological study at the Children's Hospital, University of Cincinnati; and 69 boys, 42 girls, 16 men, and 23 women as part of population-based studies at Federico II University of Naples, Italy. Among the 766 subjects, 393 were older than 17 years, and 330 were female (166 children to adolescents and 164 adults). Among the 373 children and adolescents, 286 were white (126 females), 86 were black (40 females), and 1 boy was Hispanic. Among the 393 adults, 281 were white (103 women), 78 were black (41 women), 19 were Hispanic (10 women), 10 were Asian (8 women). and 5 were Native Americans (2 women).
All participants had blood pressures (BPs) that were consistently normal, according to traditional clinical criteria for adults (<140/90 mm Hg) and according to the definition of hypertension in children based on age, sex, and height presented by Rosner et al9 for American children and by the Italian Blood Pressure Tables of the Italian Society of Pediatrics for Italian children who have been reported to have higher average BP than children of the same age from other European countries.10 Children younger than 1 year old were assumed to have normal BP when systolic and diastolic pressures were lower than 101/55 mm Hg (the 95th percentile of BP values in 1-year-old boys at the 25th percentile of height).9 All participants were also normal-weight according to the 1985 National Institutes of Health Consensus Conference11 or the Himes and Dietz simplified criteria for children.12
Procedures
Informed consent was obtained from all adult volunteers and from
parents or guardians of children under protocols approved by the
Institutional Review Boards for Research in Human Subjects in the
United States and the Ethics Committee of Federico II University
Hospital in Naples. Because the echocardiographic study
in Italy was performed in a school site, formal approval by the School
Authority was also required.
Two-dimensionally targeted M-mode echocardiograms were performed as previously described,13 with the subjects in a partial left decubitus position and in held expiration when possible, using commercially available echocardiographs. Tracings were recorded on strip-chart paper at 50 mm/s, coded, and interpreted blindly in each center. Measurements of interventricular septal thickness, posterior wall thickness, and left ventricular (LV) dimensions were taken at or just below the mitral valve tips, by the leading edge–to–leading edge method, according to recommendations of the American Society of Echocardiography.14 Segmental wall motion abnormalities were excluded by two-dimensional echocardiographic recording in multiple standard projections. LV end-diastolic and end-systolic volumes were calculated with the Teichholz correction of the cube formula.15 LV chamber volumes and stroke volume determined with this approach have been shown to correlate well with invasive and two-dimensional and Doppler echocardiographic volume measurements in a variety of populations with symmetric LV wall motion.16 BP was recorded at the end of the echocardiographic examination with an arm-cuff sphygmomanometer and appropriately sized cuffs for children and infants. BP values were used to calculate pulse pressure as the difference between systolic and diastolic values. Stroke volume was therefore divided by pulse pressure (SV/PP ratio) to provide a measure of total systemic arterial compliance.
Statistical Analysis
Because Italian children had BP values slightly higher than
same-age American children, analyses have been adjusted for
"center effect" using the following procedure: Primary
echocardiographic measurements
(end-diastolic and end-systolic LV internal
dimension and wall thickness), BP, and heart rate were related as
dependent variables to a dichotomous variable
representing the center in age-matched groups of subjects.
Thus, Italian children were combined with Cincinnati children in the
same age range (6 to 11 years) and Italian adults were combined with
New York adults in the same age range (20 to 69 years), and dependent
variables were related to the dummy variable indicating the
center (1 or 2). The variables considered in this preliminary
analysis were therefore adjusted using the linear coefficient
of regression (b). Thus the adjusted variable (adjV) was
adjV=V-b(x-µ), where V is the
observed value of the dependent variable, x is the dummy
variable representing the center, and µ is the
average value of the variable representing the centers.
When needed, this approach was also used to adjust SV/PP ratio to body
size or heart rate.
Data are expressed as mean±SD. For categorical variables,
2 statistics was used. One-factor ANOVA was used
to detect between-group differences. Least-squares linear regression
was used to assess univariate relations. ANCOVA was used to
control for confounders. The SV/PP ratio was adjusted for relevant
correlates using regression coefficients as indicated above. To compare
the rates of change in SV/PP ratio, pulse pressure, and stroke volume
with age, the slopes of the age-specific regression lines were examined
after standardization of variables to a mean of 1 and an SD
corresponding to the coefficient of variability of the original
variables.17 With this approach, the slopes of the
lines relating SV/PP ratio, pulse pressure, and stroke volume to age
could be compared with F statistics based on between-slopes sum of
squares.
Stepwise multiple regression analysis was used to study the
independent correlate of the SV/PP ratio, by considering variables
initially identified as having statistically significant relations to
the SV/PP ratio in univariate analyses. F to enter
and F to remove were set to P<.05 and P<.10,
respectively. Sex was treated as a dummy variable by assigning 1 to
males and 2 to females. Race was also treated as a dichotomous
variable (white=1 and nonwhite=2). A two-tailed value of
P
.05 was considered statistically significant, but higher
P values also are reported.
|
Results |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
Table 1
shows the demographic characteristics of
this study population. All individuals were, by inclusion criteria, of
normal weight and normotensive.
|
Effect of Body Growth on SV/PP Ratio
In children and adolescents, stroke volume increased with age (Fig 1, top, P<.0001), whereas pulse pressure
tended to decrease slightly (Fig 1, bottom, P=.06). As a
consequence, SV/PP ratio markedly increased with age from birth to
adolescence (Fig 2, top, P<.0001). This
increase was completely due to body growth, as the relations became
flat when the SV/PP ratio was adjusted for mean values of body weight
and height (Fig 2, bottom).
|
|
The relation between SV/PP ratio and age was close in the 188 children up to 10 years old (r=.56, SEE=0.31 mL/beat/mm Hg, P<.0001), with an increase of 0.11 mL/beat/mm Hg per year. This was more than twofold greater than the increase in SV/PP ratio detected in the 183 children and adolescents 11 to 17 years old (0.05 mL/beat/mm Hg per year; r=.20, SEE=0.5 mL/beat/mm Hg, P<.0002; slope difference: P<.001). The increase in SV/PP ratio with age was significantly closer in white (r=.53, P<.0001, y=0.42+0.07x) than nonwhite (r=.24, P<.02, y=0.97+0.04x; between-slope difference: P=.051) children and adolescents.
The rate of change of SV/PP ratio with age was significantly higher (standardized slope=1.48) than the change in the inverse of pulse pressure (standardized slope=0.22; between-slope difference: P<.0001), whereas it was not statistically different from the rate of change in stroke volume (standardized slope=1.26).
Effect of Aging on SV/PP Ratio in Adults
In adults, stroke volume was not related to age (r=.01,
P=.9, Fig 3, top), whereas pulse pressure
increased significantly (r=.29, SEE=8 mm Hg,
P<.0001, Fig 3, bottom). The SV/PP ratio was therefore
negatively related to age from 18 to 85 years (Fig 4, top, P<.0001), with parallel regression
lines in women and men. In contrast with findings in children and
adolescents, this decrease was independent of the variance of body size
in the population, as demonstrated by the persistence of relation
between the body size–adjusted SV/PP ratio and age (Fig 4, bottom).
White and nonwhite adults exhibited similar regression lines
(r=-.16, P<.008,
y=1.89-0.005x in whites; r=-.26,
P<.006, y=1.99-0.009x in nonwhites).
The negative relation detected in the entire group was due to a faster
reduction of SV/PP ratio with age in the 123 adults older than 50 years
(0.02 mL/beat/mm Hg per year, r=-.32, SEE=0.39
mL/beat/mm Hg, P<.0003), whereas the regression line was
actually flat in the 270 adults between 18 and 50 years of age
(r=.08, P=.2).
|
|
The rate of change of SV/PP ratio with age was similar (standardized slope=-0.12) to the change in the inverse of pulse pressure (standardized slope=-0.11; between-slope difference: P=.89), whereas it was statistically higher than the rate of change in stroke volume (standardized slope=-0.005; between-slope difference: P=.01).
Influence of Heart Rate on SV/PP Ratio
Heart rate was inversely related to SV/PP ratio. This relation was
steeper in children and adolescents (reduction of 0.10 mL/beat/mm Hg
for each increase in heart rate of 10 beats per minute;
r=-.33, P<.0001) than in adults (reduction of
0.05 mL/beat/mm Hg for each increase in heart rate of 10 beats per
minute; r=-.18, P<.007; slope difference:
P<.02). The SV/PP ratio was adjusted to the age
group–specific average heart rate using the age-specific coefficient
of regression. After heart rate adjustment, the SV/PP ratio remained
positively related to age in children and adolescents
(r=.34, P<.0001) and negatively related to age
in adults (r=-.18, P<.0003).
Sex Differences in SV/PP Ratio
Although the SV/PP ratio changed similarly with age in males and
females, in either age group (Figs 2
and 4), the average values were
higher in adult men than women (Table 2 and Fig 5). This difference persisted when the
SV/PP ratio was adjusted for heart rate (P<.0001) but was
eliminated after the SV/PP ratio was adjusted for weight and height or
after the use of stroke volume normalized for body surface area (Table 2). No sex differences were detected in children and adolescents up to
17 years of age.
|
|
) and females (
).To better investigate the interrelations between sex, race, age, and body size, we examined the correlates of the SV/PP ratio by multiple linear regression models in each age stratum. In children and adolescents, the SV/PP ratio was independently associated with greater height (Ht, ß=0.32, P<.002) and body weight (BW, ß=0.22, P<.03) and with nonwhite race (ß=0.15, P<.001); the regression equation was SV/PP Ratio=0.70·Ht+0.007·BW+0.18·Race-0.26±0.39 mL/beat/mm Hg (multiple R2=.36, P<.0001). Age, sex, and heart rate did not enter the model.
In adults, the SV/PP ratio was independently related to higher body weight (ß=0.41, P<.0001), younger age (ß=-0.21, P<.0001), and lower heart rate (HR, ß=-0.15, P<.01); the regression equation was SV/PP Ratio=0.015·BW-0.007·Age-0.006·HR+1.27±0.36 mL/beat/mm Hg (multiple R2=.22, P<.0001). Body height, sex, and race did not enter the model.
|
Discussion |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
The SV/PP ratio has been proposed as an approximate measure of arterial compliance2 3 based on the principle that the arterial tree can be modeled as an elastic chamber with a constant compliance (two-element Windkessel model). In this model, the blood flow from the heart in systole (stroke volume) produces an increase in arterial pressure. The simplicity of such an assumption is questionable, but recently, measurements of arterial compliance based on the two-element Windkessel model have been shown to be more accurate than measurements based on the three-element Windkessel model (a model taking into account also the characteristic ascending aortic impedance, placed proximally to the two-element Windkessel model).18 The present study demonstrates that the SV/PP ratio identifies the expected age-related changes in total arterial compliance in adults, when physiological body growth is complete, and reveals an increase in the absolute capacitance of the arterial tree in children and adolescents during body growth.
SV/PP Ratio in Children and Adolescents
During body growth, stroke volume increases markedly with age in
boys and girls. In a system with a constant size and compliance, pulse
pressure should increase concomitant with the increase in stroke
volume. In children, pulse pressure does not change with increasing
age; in fact, we observed a weak trend toward a decrease of pulse
pressure during childhood and adolescence. The marked increase in SV/PP
ratio can therefore be attributed to an age-related increase in
"arterial capacitance" caused by the increasing body
size and parallel growth in the arterial tree, which
increases its internal volume (capacitance). As a consequence,
adjustment for body height and weight completely eliminated the
positive relation between age and SV/PP ratio in children and
adolescents (Fig 2, bottom).
SV/PP Ratio in Adults
When body growth is complete, total arterial
compliance is the result of the ability of the arterial
tree to distend in relation to a given input of blood flow. Whereas a
reduction of this ability has been documented during
adulthood,5 7 8 19 20 this reduction became evident after
age 50 in the present normal-weight, normotensive study population
(Fig 5). In early adulthood, between 18 and 50 years, age did not
affect the SV/PP ratio. Men and women exhibited the same behavior
compared with aging, although average values were lower in women than
men.5 19 21 22 We found that this sex difference was
eliminated when body size was considered as a covariate, suggesting
that the reduced SV/PP ratio in women compared with men might be at
least partly due to the smaller body size in women; stepwise regression
also suggested that body proportions might be more important than sex
in explaining the magnitude of the SV/PP ratio in adults. A potential
explanation for the apparent effect of body size on SV/PP ratio is the
known parallelism between body size and the size of the
aorta23 24 and of medium-sized capacitance vessels (eg,
common carotid artery).25 However, the SV/PP ratio is a
pure hemodynamic parameter, reflecting the
compliance of the arterial tree for that given stroke
volume. Although in our subjects, indexation of stroke volume for body
surface area eliminated the difference between normal men and women
(the SVi/PP ratio), this observation does not establish whether it is
physiologically appropriate or potentially
misleading to index stroke volume for body surface area for
incorporation into the ratio. Unless the size of the
arterial tree closely parallels the chosen measure of body
size, normalizing stroke volume in adults might actually yield a less
accurate estimate of arterial compliance. Further research
on this question is needed.
Conclusions
The SV/PP ratio is an easy-to-calculate, approximate index of
total arterial capacitance that may be useful in
epidemiological studies. The ratio increases during body growth because
of the increased size of the arterial tree; remains stable
during early adulthood, after the end of body growth; and decreases
during late adulthood to old age because of a decrease in
arterial compliance. After adjustment for body size, no
difference could be detected between adult men and women. Race does not
influence the SV/PP ratio in adults, whereas in children and
adolescents, the increase of the ratio with body growth is faster in
white than nonwhite individuals.
|
Acknowledgments |
|---|
This work was supported in part by grants HL-18323, HL-30605, HL-47540, and HL-34698 from the National Heart, Lung, and Blood Institute, Bethesda, Md, and by grant MURST-158-1993 and 1994 of the Ministry of University and Research, Italy.
Received September 3, 1996; first decision October 8, 1996; accepted November 29, 1996.
|
References |
|---|
|
TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
1. Defares JG, Wise ME. Theory of the measurement of arterial compliance in humans. Bull Math Biol. 1973;35:237-244.[Medline] [Order article via Infotrieve]
2. Ferguson JJ, Julius S, Randall OS. Stroke volume-pulse pressure relationships in borderline hypertension: a possible indicator of decreased arterial compliance. J Hypertens. 1984;2(suppl):s397-s399.
3. Randall OS, Westerhof N, van den Bos GC, Alexander B. Reliability of stroke volume to pulse pressure ratio for estimating and detecting changes in arterial compliance. J Hypertens. 1986;4(suppl):s293-s296.
4.
Tatchum-Talom R, Niederhoffer N, Amin F, Makki T,
Tankosic P, Atkinson J. Aortic stiffness and left
ventricular mass in a rat model of isolated
hypertension. Hypertension. 1995;26:963-970.
5. Saba PS, Roman MJ, Ganau A, Pini R, Jones EC, Pickering TG, Devereux RB. Relationship of effective arterial elastance to demographic and arterial characteristics in normotensive and hypertensive adults. J Hypertens. 1995;13:971-977.[Medline] [Order article via Infotrieve]
6. O'Rourke M. Coupling between the left ventricle and arterial system in hypertension. Eur Heart J. 1990;11(suppl G):24-28.
7.
Vaitkevicius PV, Fleg JL, Engel JH, O'Connor FC,
Wright JG, Lakatta LE, Yin FC, Lakatta EG. Effects of age and
aerobic capacity on arterial stiffness in healthy
adults. Circulation. 1993;88:1456-1462.
8.
Kelly R, Hayward C, Avolio A, O'Rourke M.
Noninvasive determination of age related changes in the human
arterial pulse. Circulation. 1989;80:1652-1659.
9. Rosner B, Prineas RJ, Loggie JM, Daniels SR. Blood pressure nomograms for children and adolescents, by height, sex and age, in the United States. J Pediatr. 1993;123:871-886.[Medline] [Order article via Infotrieve]
10. Menghetti E, Spagnolo A, Virdis R, Strambi M e Gruppo Italiano Ipertensione Infantile. Le tavole della pressione arteriosa infantile in Italia (da 0 a 18 anni). Minerva Pediatr. 1994;46:73-82.[Medline] [Order article via Infotrieve]
11. National Institutes of Health Consensus Development Panel on the Health Implication of Obesity. Health implication of obesity. Ann Intern Med. 1985;103:1073-1077.
12.
Himes JH, Dietz WH. Guidelines for overweight in
adolescent preventive services: recommendations from an expert
committee. Am J Clin Nutr. 1994;59:307-316.
13. de Simone G, Devereux RB, Roman MJ, Ganau A, Saba PS, Alderman MH, Laragh JH. Assessment of left ventricular function by the midwall fractional shortening/end-systolic stress relation in human hypertension. J Am Coll Cardiol. 1994;23:1444-1451.[Abstract]
14.
Sahn DJ, DeMaria A, Kisslo J, Weyman A. The
Committee on M-Mode Standardization of the American Society of
Echocardiography: Recommendations regarding
quantitation in M-mode echocardiography: results of
a survey of echocardiographic measurements.
Circulation. 1978;58:1072-1083.
15. Teichholz LE, Kreulen T, Herman MV, Gorlin R. Problems in echocardiographic volume determination: echocardiographic-angiographic correlations in the presence or absence of asynergy. Am J Cardiol. 1976;37:7-12.[Medline] [Order article via Infotrieve]
16. Wallerson DC, Ganau A, Roman MJ, Devereux RB. Measurement of cardiac output by M-mode and two-dimensional echocardiography: application to patients with hypertension. Eur Heart J. 1990;11(suppl 1):67-78.
17.
de Simone G, Devereux RB, Daniels SR, Meyer RA.
Gender differences in cardiac growth. Hypertension. 1995;26:979-983.
18.
Stergiopulos N, Meister JJ, Westerhof N.
Evaluation of methods for estimation of total arterial
compliance. Am J Physiol. 1995;268:H1540-H1548.
19. O'Rourke M. Arterial compliance and wave reflection. Arch Mal Coeur Vaiss. 1991;84(suppl 3):45-48.
20. Hickler RB. Aortic and large artery stiffness: current methodology and clinical correlations. Clin Cardiol. 1990;13:317-322.[Medline] [Order article via Infotrieve]
21. de Simone G, Moccia D, Di Lorenzo L, Buonissimo S, Costantino G, de Divitiis O. Echocardiographic assessment of arterial impedance: relation to anatomic left ventricular patterns in systemic hypertension. Am J Noninvas Cardiol. 1988;2:232-237.
22. Hansen F, Mangell P, Sonesson B, Lanne T. Diameter and compliance in the human common carotid artery: variations with age and sex. Ultrasound Med Biol. 1995;21:1-9.[Medline] [Order article via Infotrieve]
23. Roman MJ, Devereux RB, Niles NW, Hochreiter C, Kligfield P, Sato N, Spitzer M, Borer JS. Aortic root dilatation as a cause of isolated severe aortic regurgitation. Ann Intern Med. 1987;106:800-807.
24. Roman MJ, Devereux RB, Kramer-Fox R, O'Loughlin J, Spitzer M, Robins J. Two-dimensional echocardiographic aortic root dimensions in normal children and adults. Am J Cardiol. 1989;64:507-512.[Medline] [Order article via Infotrieve]
25.
Roman MJ, Pickering TG, Pini R, Schwartz JE, Devereux
RB. Prevalence and determinants of cardiac and vascular
hypertrophy in hypertension.
Hypertension. 1995;26:369-373.
This article has been cited by other articles:
 |
|
 |
|
  J. S. Drukteinis, M. J. Roman, R. R. Fabsitz, E. T. Lee, L. G. Best, M. Russell, and R. B. Devereux Cardiac and Systemic Hemodynamic Characteristics of Hypertension and Prehypertension in Adolescents and Young Adults: The Strong Heart Study Circulation, January 16, 2007; 115(2): 221 - 227. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Mahapatra, R. A. Nishimura, P. Sorajja, S. Cha, and M. D. McGoon Relationship of Pulmonary Arterial Capacitance and Mortality in Idiopathic Pulmonary Arterial Hypertension J. Am. Coll. Cardiol., February 21, 2006; 47(4): 799 - 803. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. de Simone, P. Verdecchia, S. Pede, M. Gorini, and A. P. Maggioni Prognosis of Inappropriate Left Ventricular Mass in Hypertension: The MAVI Study Hypertension, October 1, 2002; 40(4): 470 - 476. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. Baldassarre, M. Amato, C. Palombo, C. Morizzo, L. Pustina, and C. R. Sirtori Time course of forearm arterial compliance changes during reactive hyperemia Am J Physiol Heart Circ Physiol, September 1, 2001; 281(3): H1093 - H1103. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. B. Devereux, J. N. Bella, V. Palmieri, A. Oberman, D. W. Kitzman, P. N. Hopkins, D.C. Rao, D. Morgan, M. Paranicas, D. Fishman, et al. Left Ventricular Systolic Dysfunction in a Biracial Sample of Hypertensive Adults: The HyperGEN Study Hypertension, September 1, 2001; 38(3): 417 - 423. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J H Henriksen, S Moller, S Schifter, J Abrahamsen, and U Becker High arterial compliance in cirrhosis is related to low adrenaline and elevated circulating calcitonin gene related peptide but not to activated vasoconstrictor systems Gut, July 1, 2001; 49(1): 112 - 118. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. H. Henriksen, S. Fuglsang, F. Bendtsen, E. Christensen, and S. Moller Arterial compliance in patients with cirrhosis: stroke volume-pulse pressure ratio as simplified index Am J Physiol Gastrointest Liver Physiol, April 1, 2001; 280(4): G584 - G594. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. S Hayward, W. V Kalnins, and R. P Kelly Gender-related differences in left ventricular chamber function Cardiovasc Res, February 1, 2001; 49(2): 340 - 350. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. A. Weber, J. M. Neutel, and D. H. G. Smith Contrasting clinical properties and exercise responses in obese and lean hypertensive patients J. Am. Coll. Cardiol., January 1, 2001; 37(1): 169 - 174. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. B. Devereux, M. J. Roman, M. Paranicas, M. J. O'Grady, E. T. Lee, T. K. Welty, R. R. Fabsitz, D. Robbins, E. R. Rhoades, and B. V. Howard Impact of Diabetes on Cardiac Structure and Function : The Strong Heart Study Circulation, May 16, 2000; 101(19): 2271 - 2276. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. M Montgomery, L. R Berney, and D. Blane Prepubertal stature and blood pressure in early old age Arch. Dis. Child., May 1, 2000; 82(5): 358 - 363. [Abstract] [Full Text]
|
|
|
|
|
|
C. S. Hayward, R. P. Kelly, and P. Collins The roles of gender, the menopause and hormone replacement on cardiovascular function Cardiovasc Res, April 1, 2000; 46(1): 28 - 49. [Full Text] [PDF]
|
|
|
|
|
|
J. Alfie, G. D. Waisman, C. R. Galarza, and M. I. Camera Contribution of Stroke Volume to the Change in Pulse Pressure Pattern With Age Hypertension, October 1, 1999; 34(4): 808 - 812. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. N. Bella, M. J. Roman, R. Pini, J. E. Schwartz, T. G. Pickering, and R. B. Devereux Assessment of Arterial Compliance by Carotid Midwall Strain-Stress Relation in Normotensive Adults Hypertension, March 1, 1999; 33(3): 787 - 792. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. N. Bella, M. J. Roman, R. Pini, J. E. Schwartz, T. G. Pickering, and R. B. Devereux Assessment of Arterial Compliance by Carotid Midwall Strain-Stress Relation in Hypertension Hypertension, March 1, 1999; 33(3): 793 - 799. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. de Simone, M. J. Roman, M. J. Koren, G. A. Mensah, A. Ganau, and R. B. Devereux Stroke Volume/Pulse Pressure Ratio and Cardiovascular Risk in Arterial Hypertension Hypertension, March 1, 1999; 33(3): 800 - 805. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. de Simone, R. B. Devereux, T. R. Kimball, G. F. Mureddu, M. J. Roman, F. Contaldo, and S. R. Daniels Interaction Between Body Size and Cardiac Workload : Influence on Left Ventricular Mass During Body Growth and Adulthood Hypertension, May 1, 1998; 31(5): 1077 - 1082. [Abstract] [Full Text] [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||