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Biomedical subjects

M E Safar

Publications and source records attributed to M E Safar.

At least 127 records · Page 7Linked to original sources
PubMed1995

Biaxial mechanical properties of carotid arteries from normotensive and hypertensive rats.

Hypertension is known to decrease arterial distensibility and volumetric compliance, as reported from pressure-volume experiments and ring and strip studies of human and animal large arteries. However, recent data using noninvasive in vivo recording of vessel diameter suggest that the cross-sectional compliance of large arteries can be unchanged or even increased in hypertensive subjects. The present study was performed to test the hypothesis that differences between volumetric and cross-sectional compliance could be related to differences in biaxial mechanical properties in normotensive and hypertensive rats. In normotensive (Wistar-Kyoto [WKY]) rats and spontaneously hypertensive rats (SHR) we measured the simultaneous changes in length and diameter of in situ isolated carotid arteries submitted to static pressures (50 to 200 mm Hg by steps of 25 mm Hg each). Carotid artery diameters and lengths were determined by video microscopy and computer-assisted image analysis. At low transmural pressure (50 mm Hg), carotid artery diameter was 710 +/- 41 microns in WKY rats and 980 +/- 31 microns in SHR (P < .01). In response to pressure increases, the carotid diameter increased by 91 +/- 6% in WKY rats and by 41 +/- 4% in SHR (P < .01). In parallel, the percent increase in carotid length was much larger in WKY rats than in SHR (31 +/- 2% versus 7 +/- 1%, respectively; P < .01). In WKY rats, longitudinal distensibility causes significantly larger volumetric values than cross-sectional compliance values; in contrast, because of the very small longitudinal distensibility, volumetric and cross-sectional compliances are almost identical in SHR.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1995

Proximal and distal pulse pressure after acute antihypertensive vasodilating drugs in Wistar-Kyoto and spontaneously hypertensive rats.

OBJECTIVE: In a previous study (J Hypertens 1993, 11:135-139) our group showed that in anaesthetized rats, although pulse pressure increased from the proximal (common carotid artery) to the distal (terminal aorta) portion of the aorta in normotensive Wistar-Kyoto (WKY) rats, such a pulse pressure gradient was not observed in spontaneously hypertensive rats (SHR) which had identical values of proximal and distal pulse pressure. The purpose of the present study was to show, in awake SHR, in comparison with awake WKY rats, that the lack of pulse pressure gradient might be functionally reversed after acute administration of vasodilating agents. METHODS: The drugs (administered intra-arterially) were an angiotensin converting enzyme inhibitor (perindoprilat; 2 mg/kg), a calcium antagonist (nicardipine; 30 micrograms/kg), a peripheral vasodilator (hydralazine; 200 micrograms/kg) and placebo (isotonic saline). Blood pressure was evaluated invasively. RESULTS: In untreated rats it was noticed that pulse pressure increased physiologically from the proximal to the distal part of the aorta for the same mean arterial pressure in WKY rats, whereas no pulse pressure gradient was observed in SHR. With acute drug administration, marginal modifications were observed in WKY rats, but mean arterial pressure was reduced significantly in SHR (hydralazine > perindoprilat > nicardipine). Proximal pulse pressure was decreased significantly with perindoprilat or nicardipine but was unchanged with hydralazine. Distal pulse pressure was unchanged, except for an increase in the nicardipine-treated group. Heart rate was increased significantly by hydralazine. CONCLUSION: The results show that, although all of the drugs studied decreased mean arterial pressure in SHR, only the calcium antagonist nicardipine and the angiotensin converting enzyme inhibitor perindoprilat reduced proximal pulse pressure. This dissociation between the effects on mean arterial pressure and proximal and distal pulse pressure can be explained by the preferential action of the different antihypertensive agents on large arteries and wave reflections, producing different patterns in the pulsatile component of the heart load.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1995

Blood pressure and serum lipids in hypertensive men and women aged 60-97 years.

OBJECTIVE: To report a large set of observations on blood pressure and blood lipids including high-density lipoprotein cholesterol in male and female hypertensive subjects aged 60 years or above. METHODS: Data on blood pressure (BP), total cholesterol (C), and high-density lipoprotein cholesterol (HDL-C) were made available on 5310 hypertensive subjects aged 60-97 years, from a European study on the effects of urapidil, a multifactorial antihypertensive agent (alpha 1-adrenoceptor antagonist+control 5HT1A-receptor stimulant). Observations before treatment were analysed to assess the male-female difference and the changes with age of BP and serum lipids. The subjects were divided into 7 groups, aged 60-62, 63-65, 66-68, 69-71, 72-76, 77-79, and 80+, respectively, and a 2-factor ANOVA (sex and age groups) was used. RESULTS: Systolic BP increased with increasing age in both sexes (p < 0.0001). Over the whole age range, SBP was higher in women than in men (p < 0.0001). Diastolic BP remained unchanged in men and decreased with increasing age in women (p < 0.001). The C level was almost the same in men as in women, but tended to decrease with increasing age in women (p < 0.05). HDL-C was unchanged in men, but increased with increasing age in women (p < 0.006). In all age ranges, the HDL-C level was higher in women than in men (p < 0.0001). CONCLUSION: This study reports observations on BP and serum lipids in a large sample of hypertensives subjects aged 60-97 years. This type of data, especially on high-density lipoprotein cholesterol, is rare in the elderly.

Aged↗
PubMed1994

Arterial stiffness and wave reflections following acute calcium blockade in essential hypertension.

Antihypertensive agents are routinely studied in terms of changes in the level of systolic, diastolic, and mean arterial pressure. Pulse pressure may be independently modified from these parameters as a consequence of specific changes in the mechanical properties of the large arteries and in the timing of incident and reflected pressure waves. The aim of this study was to evaluate the changes in pulse pressure produced by acute calcium blockade by the dihydropiridine derivative, lacidipine, in a double-blind design versus placebo in 18 subjects with mild to moderate hypertension. Carotid and femoral pressure waveforms were recorded noninvasively by applanation tonometry using a Millar micromanometer-tipped probe. Early (Pi) and mid-to-late (Ppk) systolic peaks of carotid pressure waveform were evaluated, enabling the effect of incident pressure wave to be quantified as the ratio of Pi to the total height of carotid pulse wave (PP) (Pi/PP) and the effect of wave reflections as the ratio (Ppk-Pi)/PP. Travel time of the reflected wave (delta tp) was timed from the foot of the pressure wave to the foot of the late systolic peak. Pulsatile changes in diameter were studied using noninvasive echo-tracking techniques. Whereas mean arterial pressure significantly decreased following lacidipine, pulse pressure measured at three different sites (brachial, carotid, and femoral arteries) was unchanged. Carotid-femoral pulse wave velocity, carotid and femoral arterial stiffness, and delta tp were not modified, whereas the (Ppk-Pi)/PP ratio and left ventricular ejection time was significantly reduced and the Pi/PP ratio was significantly increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Arteries↗
PubMed1994

Life survival and cardiovascular structures following selective beta-blockade in spontaneously hypertensive rats.

The aim of this study was to assess life survival, and arterial and cardiac structural changes following chronic selective beta-blockade in spontaneously hypertensive rats (SHR). Twenty-two SHR aged 3 months and 20 SHR aged 18 months were treated with the beta 1-blocking agent bisoprolol (10 mg/kg/day) or placebo for a period of 2 months. At the end of this period left and right ventricular weight and morphometric parameters of five different arterial segments (thoracic and abdominal aorta, renal, mesenteric, and carotid arteries) were evaluated. In younger SHR, systolic blood pressure (tail-cuff method) was significantly lower in drug-treated animals (225 +/- 15 v 185 +/- 10 mm Hg in placebo-treated animals; P < .001); left ventricular weight was significantly lower in drug-treated rats (0.845 +/- 0.02 v 0.932 +/- 0.03 g; P < .05); medial thickness was significantly lower in the bisoprolol-treated rats at the site of the thoracic (-22%) and abdominal (-17%) aorta, and mesenteric artery (-29%); in the renal and carotid arteries, no change in medial thickness was observed. In older SHR, cardiovascular morbidity and mortality were significantly higher (P < .01) in the placebo group. In bisoprolol-treated animals, systolic blood pressure did not change and was even significantly higher than in controls. Heart weight and medial thickness of the thoracic aorta and the renal arteries were significantly lower in the Bisoprolol group. These results provide evidence that 2 months of selective beta-blockade in adult SHR has an important antihypertrophic cardiac and vascular effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗
PubMed1994

Arterial pulse wave and calcium-channel blockers in hypertension.

In contrast to mean blood pressure, arterial pulsatility represented by pulse pressure (PP) varies from heart to periphery. It depends on the stiffness of large arteries and the degree of arteriolar vasoconstriction. The central pulsatility, directly linked to left ventricular work, cannot be accurately evaluated by measurement of brachial PP. Moreover, the pulse wave reflection, when arriving in systole, increases the late-systolic pressure and the left ventricular afterload, particularly in older and hypertensive subjects. Analysis of the central pressure curve recorded by an accurate noninvasive method (applanation tonometry) may improve the hemodynamic evaluation of antihypertensive drugs. Calcium blockers reduce cardiac afterload in hypertension by their arteriolar vasodilating properties, by improving the compliance of large arteries, and also by reducing the central influences of the reflection wave, as shown after single administration and particularly after chronic treatment with calcium blockers.

Arteries↗
PubMed1994

Early disturbance of baroreflex control of heart rate after tail suspension in conscious rats.

Experiments were performed on conscious chronically instrumented rats maintained on tail suspension to determine the time course of changes in baroreceptor control of heart rate produced by this procedure. Pressor responses were elicited by bolus injections of graded doses of phenylephrine and sodium nitroprusside, permitting evaluation of the totality of the sigmoidal curve relating mean arterial pressure to heart rate. Compared with control rats maintained at 0 degrees, rats maintained at 20 degrees using tail suspension for 24 h showed a significant reduction in reflex gain (-3.9 +/- 0.1 vs. -5.8 +/- 0.3 beats/min; P < 0.001) together with a reduction in the upper (472 +/- 11 vs. 512 +/- 5 beats/min; P < 0.01) and lower (270 +/- 3 vs. 284 +/- 2 beats/min; P < 0.01) plateaus of the sigmoidal curve. In three groups of rats, the sigmoidal curve was studied successively after returning for 1, 24, and 48 h at 0 degrees. The observed change in the gain of the reflex returned toward control values after 48 h, whereas the other parameters characterizing the sigmoidal curve did not change significantly. Transient but significant modifications of heart rate (tachycardic response) after the immediate return to the horizontal position were observed. The study provides evidence that 1) a significant change of the totality of the sigmoidal curve characterizing baroreceptor control of heart rate occurs very early after tail suspension in rats and 2) the gain of the reflex is restored during the 48 h after release of tail suspension, whereas the other parameters characterizing the curve, particularly the plateaus, remain altered.

Animals↗
PubMed1994

Cardiac hypertrophy, aortic compliance, peripheral resistance, and wave reflection in end-stage renal disease. Comparative effects of ACE inhibition and calcium channel blockade.

BACKGROUND: We wished to assess the respective roles of the antihypertensive and blood pressure (BP)-independent effects of antihypertensive drugs on arterial hemodynamics and left ventricular hypertrophy (LVH) in end-stage renal disease (ESRD) patients. METHODS AND RESULTS: In a double-blind study, 24 ESRD patients with LVH were randomized to 12 months' administration of either the angiotensin-converting enzyme (ACE) inhibitor perindopril (n = 14) or the calcium channel blocker nitrendipine (n = 10). Repeated measurements of the following parameters were performed: BP (mercury sphygmomanometry), left ventricular mass (LVM, echocardiography), cardiac output (aortic cross-section and velocity integral), total peripheral resistance (cardiac output and mean BP), aortic and large-artery compliance (pulse wave velocity, Doppler flowmeter), and arterial wave reflections (augmentation index, applanation tonometry). Radioimmunoassay was used to determine plasma renin activity, aldosterone, and plasma catecholamine levels. Two-way (time-treatment) ANOVA for repeated measures was used for statistical analysis. Perindopril and nitrendipine induced significant and similar decreases in BP, total peripheral resistance (P < .001), aortic and arterial pulse wave velocities (P < .001), and arterial wave reflections (P < .01). At baseline, the two groups had LVH mostly due to increased LV end-diastolic diameter (LVEDD) (perindopril, 54.3 +/- 1.4 and nitrendipine, 54.3 +/ 2.4 mm) with near-normal mean LV wall thickness (perindopril, 11.4 +/- 0.3 and nitrendipine, 11.2 +/- 0.4 mm). A decrease in LVM was observed only in patients receiving perindopril (from 317 +/- 18 to 247 +/- 21 g) (time-treatment interaction, P = .036). Nitrendipine had no significant effect on LVM (314 +/- 29 versus 286 +/- 32 g). The decrease in LVM observed with perindopril was associated with a reduction in LVEDD (49.9 +/- 1.6 versus 54.3 +/- 1.4 mm after 12 months) (time-treatment interaction, P = .04), while the mean LV wall thickness was unchanged (11.4 +/- 0.3 versus 10.5 +/- 0.5 mm). Cardiac alterations were not correlated with changes in BP or with alterations in plasma renin activity or aldosterone or catecholamine levels. CONCLUSIONS: In ESRD patients with LVH, ACE inhibition decreases LVM independently of its antihypertensive effect and of associated alterations in arterial hemodynamics. The decrease in LVM was due primarily to a decrease in LV volume, which may have resulted in these patients from chronic volume overload.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1994

Angiotensin converting enzyme inhibition prevents the increase in aortic collagen in rats.

Four groups of 4-week-old spontaneously hypertensive rats were treated during 4 months with the angiotensin converting enzyme inhibitor quinapril at 1 mg/kg per day (Q1) or 10 mg/kg per day (Q10), hydralazine at 15 mg/kg per day (H), or placebo (P). In the first set of experiments, blood pressure was measured in conscious rats, and plasma and aortic angiotensin converting enzyme activities were evaluated. In the second set of experiments, histomorphometric parameters of the thoracic aorta were evaluated. Mean blood pressure was lower in the Q10 and H groups (136 +/- 16 and 149 +/- 11 mm Hg) compared with the P group (190 +/- 23 mm Hg) (P < .01). The Q1 group showed mean blood pressure values (171 +/- 15 mm Hg) lower than the P group (P < .05) but significantly higher than the Q10 and H groups (P < .01 and P < .05, respectively). Aortic medial cross-sectional area was significantly lower in the H and Q10 groups (455 +/- 61 and 487 +/- 57 x 10(3) microns 2) than in the P group (636 +/- 72 x 10(3) microns 2) (P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1994

Comparison of the efficacy and safety of trandolapril and captopril for 16 weeks in mild-to-moderate essential hypertension. Investigator Study Group.

This multicenter international trial recruited 180 patients from 27 investigators. After a 4-week, single-blind placebo run-in, patients were randomized double-blind to 16 weeks of trandolapril 4 mg o.d. or captopril 50 mg b.i.d. If blood pressure was not normalized at 8 weeks, hydrochlorothiazide (HCTZ) 25 mg was added. Morning predosing supine diastolic blood pressure (DBP) was the primary efficacy measurement. At 8 weeks, the intention-to-treat analysis showed a significant difference for supine DBP (mean +/- SEM) between the two groups: trandolapril -13.5 +/- 0.9 mm Hg; captopril -10.1 +/- 1.0 mm Hg (p = 0.007). The proportion of patients whose blood pressure was normalized was 61% for trandolapril and 44% for captopril (p = 0.02). At 8 weeks, 26% of the trandolapril group received HCTZ compared with 38% taking captopril. The addition of HCTZ further increased the antihypertensive effect in patients who had shown only moderate reductions in blood pressure after drug monotherapy. Both treatments were well tolerated clinically and biochemically. Withdrawals owing to adverse events were three from trandolapril and eight from the captopril group. Trandolapril given once daily is an effective and well-tolerated antihypertensive agent that, in this study, exhibited better efficacy compared with captopril. When blood pressure is not sufficiently controlled with monotherapy, the combination of trandolapril and HCTZ enhances the antihypertensive effect.

Adult↗
PubMed1994

Ambulatory blood pressure profile after carotid endarterectomy in patients with ischaemic arterial disease.

OBJECTIVE: To assess the circadian blood pressure profile observed 3 months after endarterectomy. DESIGN: Twenty-five patients undergoing unilateral or bilateral carotid endarterectomy were compared with a control population of 20 patients, matched for age, sex, weight and drug therapy. Casual mean blood pressure measured by mercury sphygmomanometry was similar in both groups. RESULTS: Non-invasive ambulatory blood pressure monitoring showed that, whereas mean arterial pressure was identical in both groups, the group undergoing surgery had a significant increase in pulse pressure and its variability over 24 h. Such abnormalities predominated during the nocturnal period, in which the reduction in systolic blood pressure was less pronounced in the operated group than in controls. For all parameters there was no significant difference between subjects with unilateral or bilateral endarterectomy. CONCLUSION: This study provides evidence that patients with carotid endarterectomy were characterized in the long term by an increase in the pulsatile component of blood pressure and its variability, in association with a disturbance in the physiological circadian rhythm. Such findings were not identified using casual blood pressure measurements.

Aged↗
PubMed1994

Acute and long-term effects of angiotensin converting enzyme inhibition on larger arteries and cardiac hypertrophy: mechanical and structural parameters.

AIM OF STUDIES: The extent of cardiovascular alterations in hypertension is related quantitatively to the degree of hypertension. However, there is increasing evidence that humoral processes, which are not dependent on blood pressure, are of major importance in these alterations. In particular, angiotensin converting enzyme (ACE) activity seems to be involved. We therefore compared the effects of blood pressure reduction and of acute and long-term ACE inhibition on cardiac hypertrophy, arterial function and morphologic alterations in hypertension. ACUTE STUDY: To examine the acute effect of ACE inhibition on arterial compliance, we used an experimental model allowing a pressure-volume determination in the carotid artery in situ to assess arterial compliance in normotensive Wistar-Kyoto and spontaneously hypertensive rats. The pressure-volume relationship was determined after an acute, single, oral administration of either placebo or the ACE inhibitor quinapril in doses of 0.3 and 3 mg/kg. Both doses of quinapril produced a similar relaxation of arterial smooth muscle, approximately 80-90% of the maximum relaxation produced by potassium cyanide. LONG-TERM STUDY: We then studied the long-term effects of ACE inhibition compared with those of hydralazine. Four groups of 4-week-old spontaneously hypertensive rats were treated for 4 months with quinapril at 1 or 10 mg/kg per day, hydralazine at 15 mg/kg per day or placebo. Blood pressure, plasma and aortic ACE activity, left ventricular weight and histomorphometric parameters of the thoracic aorta, the renal and the mesenteric arteries were evaluated. We found a marked dissociation between the effects on blood pressure and cardiovascular structural parameters. Whereas both hydralazine and 10 mg/kg quinapril prevented the development of hypertension and aortic hypertrophy in a pressure-dependent manner, only the ACE inhibitor prevented left ventricular hypertrophy and aortic collagen accumulation. These quinapril effects were observed even with a small non-antihypertensive dose (1 mg/kg); the effect on aortic collagen was related to a reduction in aortic but not plasma ACE. CONCLUSIONS: These results indicate that the acute and long-term effects of ACE inhibitors on arterial function and structure go well beyond their antihypertensive actions and seem to be related to inhibition of tissue ACE. However, while clear effects were observed in the particular arterial segment explored, it may not be valid to extrapolate these findings to other arterial segments.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1994

Intrinsic modifications of the brachial and radial arteries in hypertensive humans.

The properties of vessel walls of brachial and radial arteries were studied noninvasively, using 2 original pulsed ultrasound echo-tracking systems based on Doppler shift, in an investigation comparing 32 normotensive controls and 50 age-matched hypertensive patients. The 2 groups did not differ with respect to sex, total and high-density lipoprotein cholesterol, blood glucose, and smoking habits. Whereas noninvasive measurements of blood pressure indicated that both mean arterial pressure and pulse pressure were significantly increased in the arterial tree of the hypertensive forearm, end-diastolic diameter and pulsatile changes of the brachial and radial arteries remained within the normal range. The finding was more pronounced at the site of the radial artery in which: (i) pulsatile changes of blood pressure (documented from Finapres method) were significantly higher than those of the brachial artery, yet (ii) indices of arterial stiffness (compliance and distensibility) remained within the normal range. For the branchial artery, distensibility was significantly reduced (p = 0.01), whereas no significant change in compliance was observed. The study provides evidence that, in subjects with essential hypertension, the mechanical properties of the brachial and the radial arteries are not exclusively related to the level of blood pressure, and differ according to the arterial segment studied.

Adult↗
PubMed1994

Placebo-controlled crossover comparison of spirapril at 3, 6, 12 and 24 mg once daily in mild to severe essential hypertension.

In a randomized, double-blind, crossover study, 20 patients with mild to severe essential hypertension received 3 weeks of treatment with each of four dosages of spirapril (3, 6, 12 and 24 mg once daily) or placebo. Standing and supine blood pressures were measured by use of both an automatic oscillometric instrument (Dinamap) and a mercury sphygmomanometer over a 24-hour period. Spirapril at 6, 12 and 24 mg once daily produced similar reductions in systolic and diastolic blood pressure. At most time points, there was a statistically significant difference between the reductions with spirapril compared with placebo. Spirapril at 3 mg once daily was less effective than the higher dosages, producing a lower mean blood pressure reduction and a shorter duration of antihypertensive action, mainly as regards systolic pressure. Spirapril was well tolerated and no patients withdrew from the study because of adverse effects. These data suggest that, although all four evaluated spirapril dosages effectively lowered supine and standing blood pressure in patients with mild to severe hypertension, the blood pressure-lowering effect of the 3 mg/day regimen was less than optimal. There were only minor variations in efficacy between dosages > or = to 6 mg/day, which may be attributable to the variability of blood pressure. Further investigations of larger numbers of patients are required to verify these results.

Adolescent↗
PubMed1994

Sodium, large arteries, and diuretic compounds in hypertension.

Clinical and experimental data have shown that antihypertensive drugs do not cause the same change in arterial compliance for an equipotent blood pressure reduction. However, there is not clear data on the effect of sodium and diuretics on the visco-elastic properties of the hypertensive arterial wall. Cross-sectional epidemiologic studies suggest that, at any given value of age and blood pressure, pulse wave velocity is lower in the presence of decreased sodium intake. Longitudinal studies indicate that, in hypertensive subjects, low sodium intake is associated with a larger brachial artery diameter than is high sodium intake. In hypertension in the elderly and in severe hypertension with end-stage renal disease, sodium overload causes a reduction in arterial compliance and distensibility unrelated to blood pressure changes. In animal studies, the diuretic compounds cycletanine and indapamide were shown to increase systemic and carotid compliance independently of blood pressure changes. In contrast, a crossover study of hypertensive subjects showed that the diuretic agent hydrochlorothiazide did not change arterial compliance and pulse wave velocity, whereas the calcium entry blocker, felodipine, improved these parameters. Nevertheless, indapamide decreased the pulse pressure on stroke volume ratio, a parameter used as a marker of aortic distensibility. Taken together, such studies indicate that sodium may act on the arterial wall independently of blood pressure changes. The contribution of counter regulatory mechanisms, possibly related to the renin-angiotensin and sympathetic nervous systems, might explain the differences between the clinical and experimental changes observed with diuretic compounds. Of the various antihypertensive agents, diuretics seem to have the least effect on the arterial system.

Animals↗
PubMed1994

Abnormalities of lipid metabolism and arterial rigidity in young subjects with borderline hypertension.

Plasma lipoprotein levels and carotid-femoral pulse wave velocity, used as a marker of aortic rigidity, were evaluated in 53 young subjects with borderline hypertension by comparison with normotensive controls of the same age and body surface area. Subjects with body weight excess, exaggerated alcohol intake, and/or tobacco consumption were excluded from the study. Borderline hypertensive patients were characterized by significantly higher values of pulse wave velocity and plasma levels of glucose, total cholesterol, high density lipoprotein subfraction HDL3, apolipoprotein B, and lipoprotein (a). There were no group/sex interactions. A significant dyslipidemia was observed in 13 males of the 53 borderline hypertensive subjects. Only in this subgroup did subjects exhibit a strong positive relationship between pulse wave velocity and either plasma total cholesterol or apolipoprotein B. The correlation was observed even after adjustment for blood pressure. The study provides evidence that, in young males with borderline hypertension, some abnormalities of plasma lipoproteins requiring treatment may be present and are associated with an increased stiffness of the arterial wall.

Adolescent↗
PubMed1993

Comparison of effects of felodipine versus hydrochlorothiazide on arterial diameter and pulse-wave velocity in essential hypertension.

In a double-blind cross-over study, the arterial changes produced by hydrochlorothiazide were compared with those observed after the calcium antagonist felodipine in 16 patients with mild to moderate systemic hypertension. Diameter changes at the site of the common carotid and brachial arteries were investigated using pulsed Doppler velocimetry, and pulse-wave velocities of the aortic, brachial and femorotibial areas were measured using standard noninvasive techniques. Whereas hydrochlorothiazide and felodipine similarly decreased blood pressure, hydrochlorothiazide did not change pulse-wave velocity, and the diameters of the brachial and common carotid arteries. Felodipine significantly decreased pulse-wave velocity, and increased brachial arterial diameter and compliance, with no change in carotid arterial diameter. Evidence was found that although felodipine had specific effects on the arterial system of hypertensive subjects, hydrochlorothiazide did not produce any sizable arterial change. These differential effects may influence specifically the heart afterload, with important consequences for diuretics that are known to cause minimal changes in cardiac structure and function.

Adult↗