Search PubMed⌕ Search

Biomedical subjects

F H Messerli

Publications and source records attributed to F H Messerli.

At least 289 records · Page 16Linked to original sources
PubMed1982

Borderline hypertension and obesity: two prehypertensive states with elevated cardiac output.

Systemic, renal and splanchnic hemodynamics, intravascular volume, circulating catecholamine levels and plasma renin activity were compared in 39 patients with borderline hypertension and 28 normotensive subjects, who were less than 5% (n = 42, lean patients) or more than 40% overweight (n = 25, obese patients). Lean borderline hypertensive patients had greater cardiac output (p less than 0.05), heart rate (p less than 0.01) and renal blood flow (p less than 0.05); cardiopulmonary redistribution of intravascular volume (p less than 0.05); and higher circulating norepinephrine levels (p less than 0.05). Obese normotensive subjects also showed an increased cardiac output (p less than 0.005), stroke volume (p less than 0.01), left ventricular stroke work (p less than 0.05), and renal blood flow (p less than 0.05) (but not respective indexes), but intravascular volume was expanded (p less than 0.05) without redistribution and circulating catecholamine levels were normal. Obese borderline hypertensive patients had hemodynamic characteristics similar to those of obese normotensive subjects except for an increased peripheral resistance (p less than 0.05). The data indicate that although both populations have an increased cardiac output, the lean borderline hypertensive patients have signs of enhanced adrenergic activity as evidenced by higher circulating catecholamine levels and heart rate with blood volume translocation to the cardiopulmonary circulation. In contrast, the obese subjects (whether normotensive or borderline hypertensive), who also have increased cardiac output, seem to have normal adrenergic activity and an expanded intravascular volume without cardiopulmonary redistribution.

Adult↗
PubMed1982

Arterial compliance in systolic hypertension.

Arterial compliance as estimated by pulse wave velocity and the pulse pressure/stroke volume index was evaluated in 27 normotensive subjects, 21 patients with established, and 18 patients with systolic essential hypertension. Pulse wave velocity was elevated to the same degree in both hypertensive groups when compared to the normotensive controls. The pulse pressure/stroke volume index was higher in essential hypertension than in normotensive subjects and even higher in patients with systolic hypertension. It is concluded that both indices are useful clinical tools to determine arterial compliance. Systolic hypertension does not always indicate stiffening of the arterial tree, but may result from a high stroke volume in the presence of a normal arterial compliance.

Aorta, Thoracic↗
PubMed1981

Obesity and essential hypertension. Hemodynamics, intravascular volume, sodium excretion, and plasma renin activity.

Systemic hemodynamics, intravascular volume, and plasma renin activity were determined in 135 lean, midly obese, or distinctly overweight subjects who were normotensive or had borderline or established essential hypertension. Cardiac output (but not index) was higher and peripheral resistance lower in obese than in lean subjects, except in borderline hypertension. Intravascular volume was increased in obese patients, and more so when corrected for body height; correction for body weight led to relative volume contraction. Intravascular volume correlated directly with cardiac output in the entire population, as well as in the subgroups. Intravascular volume correlated inversely with total peripheral resistance in all subjects and in each subgroup. Both correlations remained significant when an approximation was used to correct influences of obesity on total blood volume. Sodium excretion was higher in obese than in lean subjects. Thus, despite the expanded intravascular volume in obesity, the pathophysiologic relationship between systemic hemodynamics and intravascular volumes remains unchanged. Relatively low peripheral resistance in obesity may decrease the risk of systemic vascular disease. Nevertheless, since circulating volume is increased, the greater venous return adds an additional load to a left ventricle that is already burdened by a high afterload caused by arterial hypertension.

Adult↗
PubMed1981

Echocardiographic diastolic ventricular abnormality in hypertensive heart disease: atrial emptying index.

To analyze changes in left ventricular diastolic properties in hypertensive heart disease, the atrial emptying index was used to assess the rapid phase of diastolic filling of the left ventricle. Ten normal subjects (Group 1), 11 hypertensive patients without evidence of cardiac involvement (Group 2) and 10 hypertensive patients with echocardiographic evidence of left ventricular hypertrophy (Group 3) were compared using M mode echocardiography and systemic hemodynamic data. Whereas cardiac index (dye-dilution method) and rate of circumferential fiber shortening (echocardiogram) were normal in all three groups, there was a progressive increase in left atrial index (p less than 0.001, Group 1 versus Group 2 and versus Group 3) and a progressive decrease in the atrial emptying index (p less than 0.001, Group 1 versus Group 2 and versus Group 3). No correlation existed between the atrial emptying index and the left atrial index, mean arterial pressure or total peripheral resistance in any of the three groups. These data suggest that rapid filling of the left ventricle is reduced early in hypertension, even before electrocardiographic or systolic echocardiographic abnormalities are detectable. The atrial emptying index therefore appears to be an early indicator of abnormalities of left ventricular diastolic compliance in uncomplicated hypertension.

Adult↗
PubMed1981

Hypertension in the elderly: haemodynamic, fluid volume and endocrine findings.

1. Systemic and renal haemodynamics, intravascular volume, circulating catecholamines and plasma renin activity were measured in 18 patients with established essential hypertension who were older than 60 years of age. Each patient was matched with respect to mean arterial pressure, body surface area, race and sex with a patient that was younger than 42 years of age. 2. When compared with the younger group, elderly patients had a lower cardiac output, impaired myocardial reserve, lesser aortic elasticity, higher total peripheral resistance, more contracted intravascular volume and higher circulating noradrenaline levels. 3. Similar effects of age, although less pronounced, have been reported in normotensive subjects. We conclude that essential hypertension is a pathophysiological process that seems to accelerate the natural physiological haemodynamic, fluid volume and endocrine processes of aging.

Adult↗
PubMed1981

Borderline hypertension: relationship between age, hemodynamics and circulating catecholamines.

The relationships between age, systemic and renal hemodynamics, circulating catecholamines (norepinephrine, epinephrine and dopamine) and intravascular volumes were studied in 38 normotensive subjects and in 77 patients with borderline essential hypertension. Borderline hypertensive patients had a higher cardiac index (p less than 0.02) and renal blood flow (p less than 0.05) than normotensive subjects if they were younger than 30 years of age, whereas in older patients no difference was observed. In contrast, total peripheral resistance was normal in young borderline hypertensive patients, but significantly increased (p less than 0.02) in patients older than age 40 years. Cardiac output (r = -0.28, p less than 0.01) and renal blood flow (r = -0.47, p less than 0.001) correlated inversely with age in the entire population and in both subgroups. Cardiac output also correlated closely with renal blood flow in all subjects (r = 0.45, p less than 0.001). Circulating norepinephrine levels increased with age (r = 0.25, p less than 0.05), whereas epinephrine concentration tended to decrease. Plasma and total blood volume correlated directly with cardiac output (r = 0.39, p less than 0.001) and inversely with peripheral resistance (r = -0.34, p less than 0.001). These data indicate that the hyperdynamic circulation (high cardiac output and renal blood flow) of borderline hypertension is found predominantly in patients younger than age 30 years. Older patients are characterized by an elevated total peripheral resistance and normal cardiac output. The age-dependent increase in circulating norepinephrine and decrease in epinephrine levels may participate in the shift of the hemodynamic profile from high-cardiac-output hypertension in the young to a high-arteriolar-resistance hypertension in the older patient.

Adolescent↗
PubMed1981

Patterns of left ventricular adaptation in borderline and mild essential hypertension. Echocardiographic findings.

To assess patterns of left ventricular adaptation, 38 patients with borderline and 38 with sustained mild essential hypertension, all lacking electrocardiographic and roentgenographic criteria for left ventricular hypertrophy, were compared using systemic hemodynamic values and M-mode echocardiograms. All patients had normal left ventricular function and measurements of wall thickness. Those with borderline hypertension showed no asymmetric increase in the ratio of septal to posterior wall thickness. The ratio of the left ventricular radius to wall thickness remained normal in both groups, indicating no disproportionate hypertrophy or dilatation of chambers during the phase of normal left ventricular function. Neither finding substantiates asymmetric septal hypertrophy in early hypertension. Those with mild essential hypertension demonstrated an augmented mean circumferential fiber shortening rate compared to those with borderline hypertension (P less than 0.005), suggesting an early stage of left ventricular hyperfunction in the development and elaboration of hypertensive heart disease.

Adult↗
PubMed1981

Adverse effects of antihypertensive drugs.

Early essential hypertension is asymptomatic and should remain so throughout treatment. In view of the increasing number of available antihypertensive agents, clinicians need to become familiar with the potential side effects of these drugs. By placing more emphasis on non-pharmacological treatment (sodium restriction, weight loss, exercise) and thoroughly evaluating each case in particular, the pharmacological regimen can be optimally tailored to the patient's needs. Potential side effects should be predicted and can often be avoided; if they become clinically significant they should be rapidly recognised and corrected. These side effects can be easily remembered in most instances, as they fall into 3 broad categories: (a) those caused by an exaggerated therapeutic effect; (b) those due to a non-therapeutic pharmacological effect; and (c) those caused by a non-therapeutic, non-pharmacological effect probably representing idiosyncratic reactions. This review focuses mainly on adverse effects of the second and third kind. Each group of drugs in general shares the common side effects of the first two categories, while each individual drug has its own idiosyncratic side effects.

Antihypertensive Agents↗
PubMed1980

Asymptomatic mild hyperuricaemia: an indicator of nephrosclerosis in essential hypertension.

1. Glomerular filtration rate, renal and systemic haemodynamics and intravascular volume were measured in 20 established essential hypertensive patients classified according to serum uric acid level into two groups (below 0.36 mmol/l, and above 0.54 mmol/l). 2. Although glomerular filtration rate was comparable between the two groups, renal blood flow was lower and renal vascular and total peripheral resistances were higher in the patients with the highest uric acid levels (P < 0.02). 3. Cardiac output, heart rate and splanchnic blood flow were similar in both patient groups but arterial pressure tended to be higher in patients with high uric acid levels. 4. These data suggest that unexplained hyperuricaemia in patients with essential hypertension most likely reflects early renal vascular involvement, i.e. nephrosclerosis.

Adult↗
PubMed1980

Serum uric acid in essential hypertension: an indicator of renal vascular involvement.

We measured glomerular filtration rate, renal and systemic hemodynamics, and intravascular volume in normotensive subjects and in borderline and established essential hypertensive patients classified according to serum uric acid level. Renal blood flow was lower and renal vascular and total peripheral resistances were increased in patients with high uric acid levels (p < 0.02). Serum uric acid concentration correlated inversely with renal blood flow/m2 body surface area (r = -0.45, p < 0.001) and directly with renal vascular (r = 0.41, p < 0.001) and total (r = 0.38, p < 0.001) resistance. Cardiac output, heart rate, and intravascular volume as well as glomerular filtration rate showed no uric-acid-department pattern. Mild asymptomatic hyperuricemia, therefore, was associated with decreased renal blood flow without affecting glomerular filtration rate. Increased renal vascular and total peripheral resistances reflecting renal and systemic hypertensive vascular disease paralleled the rising serum uric acid levels. These data suggest that heretofore unexplained hyperuricemia in patients with essential hypertension most likely reflects early renal vascular involvement, specially, nephrosclerosis.

Adult↗
PubMed1979

High blood pressure. A side effect of drugs, poisons, and food.

Arterial hypertension, either transient or persistent, may be induced or aggravated by ingestion of various chemical agents, such as drugs, poisons, and food. Most of these agents either cause sodium retention and expand extracellular fluid volume or act as direct or indirect sympathomimetics. Others act directly on arteriolar smooth muscle. For a few agents, no precise mechanism has been ascertained. Hypertensive reactions may also occur as a result of drug interactions or food and drug interactions. In addition, paradoxical increases in pressure may be encountered during or after discontinuance of antihypertensive therapy. In general, these pressure increases are small and transient; however, a few have been associated with severe hypertension involving encephalopathy, strokes, and irreversible renal failure. Careful review of a patient's drug regimen, including over-the-counter preparations, may avoid chemically induced hypertension. Identification of any offending or incriminating agent will prevent the labeling of a chronic illness and obviate the need for lifelong antihypertensive therapy.

Androgens↗
PubMed1979

Effects of beta blockade with acebutolol on hypertension, hemodynamics, and fluid volume.

Eleven patients with essential hypertension were treated with the beta adrenergic blocker, acebutolol. Clinical, systemic, and regional hemodynamic and biochemical studies were performed before and after 4 wk of acebutolol therapy (average doses, 1,200 mg/day.) In 4 patients there was a reduction in mean arterial pressure greater than or equal to 10 mm Hg; there was none in the remainder. Regardless of the blood pressure response, the renin secretory index did not change. Although cardiac output did not change, renal blood flow fell (p less than 0.005) without relation to response of arterial pressure. Supine heart rate decreased (p less than 0.05), so also the responses to upright tilt (p less than 0.01) and isometric exercise (p less than 0.02). These results demonstrate that in those patients with a hypotensive response to acebutolol, the clinical effect was not related to reduced cardiac output or plasma renin activity, further adding to confusion on the mechanism of the lowering of elevated blood pressure by beta adrenergic blockade.

Acebutolol↗
PubMed1979

Essential hypertension in black and white subjects. Hemodynamic findings and fluid volume state.

Systemic hemodynamics (cardiac output, intraarterial pressure, total peripheral resistance) and intravascular volume (plasma volume and red cell mass) were measured in a population of 126 black and white patients, 51 with borderline hypertension and 75 with established essential hypertension. The findings were compared with those in 29 age-matched normotensive control subjects of both races. The white patients with established hypertension demonstrated a faster heart rate than the black patients (less than 0.05); this difference was more pronounced during upright tilt (p less than 0.02). No significant difference in cardiac index, total peripheral resistance, plasma volume or total blood volume was found between the two racial populations. Cardiac index correlated directly with plasma and total blood volume in black patients (r = 0.32, p less than 0.05) and white patients (r = 0.35, p less than 0.001) as well as in the whole study population (r = 0.36, p less than 0.001). The regression lines were similar in the two races. Further, a negative correlation was observed between the total peripheral resistance and plasma volume (r = -0.31, p less than 0.001) or total blood volume (r = -0.34, p less than 0.001), and it was similar in both races (blacks r = -0.48, p less than 0.01; whites r = -0.25, p less than 0.05). Age correlated significantly with total peripheral resistance in the white patients (r = 0.35, p less than 0.001) and in the total study population (r = 0.28, p less than 0.001). We conclude that, for every given age or level of arterial pressure, systemic hemodynamics are similar for the black and white patients with essential hypertension. These data, therefore, do not support the clinical impression that basic pathophysiology and hypertensive vascular disease are different in the black patient with essential hypertension.

Adult↗
PubMed1979

Systemic haemodynamic effects of biofeedback in borderline hypertension.

1. Six patients with borderline hypertension underwent training in exteroceptive biofeedback (BFB) in order to increase or decrease arterial pressure. 2. Systemic haemodynamics, intravascular volume and peripheral renin activity were determined before, during and after training sessions. 3. BFB training resulted in a significant reduction in mean arterial pressure (from 116 +/- 4.6 to 101 +/- 2.5 mmHg) mediated through a fall in total peripheral resistance; cardiac output, heart rate, intravascular volume and plasma renin activity remained unchanged. 4. In contrast, the increase or decrease of arterial pressure that occurred during BFB training was produced predominantly through changes in cardiac output and heart rate respectively, whereas total peripheral resistance under these circumstances remained unaffected. 5. The haemodynamic effects of BFB seem remarkably similar to the immediate or chronic effects of beta-adrenoreceptor blockade, initially producing a fall in cardiac output followed by a reduced arterial pressure associated with a decreased total peripheral resistance.

Biofeedback, Psychology↗