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Biomedical subjects

F H Messerli

Publications and source records attributed to F H Messerli.

At least 253 records · Page 14Linked to original sources
PubMed1984

Impaired systemic arterial compliance in borderline hypertension.

Arterial compliance was evaluated by pulse wave velocity, pulse pressure/stroke volume, and by an exponential analysis of the diastolic blood pressure decay curve in three groups of normotensive, borderline hypertensive, and established essential hypertensive patients. Two of the above three indices reflected significantly impaired arterial compliance in borderline hypertension, and all three indices were distinctly abnormal in patients with established hypertension. A close correlation among the three indices was observed in the entire study population. Multiple regression analysis indicated that age (p less than 0.005), systolic (p less than 0.005) and diastolic (p less than 0.025) pressure were independent determinants of pulse wave velocity; other factors such as total peripheral resistance, pulse pressure, and stroke volume were not. We conclude that arterial compliance becomes impaired early in hypertensive cardiovascular disease at the time when arterial pressure may be only slightly elevated. Thus structural alteration of the arterial wall can be demonstrated in borderline hypertension. Age, systolic and, to a lesser degree, diastolic pressures are the best determinants of arterial compliance in large vessels and are therefore important risk factors for evolving systemic arterial disease in essential hypertension.

Adult↗
PubMed1984

Long-term renal hemodynamic effects of nadolol in patients with essential hypertension.

Renal and systemic hemodynamic effects of nadolol, a nonselective beta-adrenergic-blocking agent, were determined over a 2-year period in eight patients with essential hypertension. Arterial pressure and heart rate remained significantly reduced for the full 2 years in all eight patients. Renal blood flow and plasma volume remained unchanged, and renal vascular resistance significantly decreased. Serum creatinine levels decreased from pretreatment values, suggesting improved glomerular filtration rates. These data demonstrate the favorable renal hemodynamic effects of nadolol monotherapy in patients with uncomplicated essential hypertension during a prolonged treatment program.

Adrenergic beta-Antagonists↗
PubMed1984

Obesity in hypertension: how innocent a bystander?

Hypertension and obesity frequently coexist in the same patient. However, the two disorders disparately affect cardiovascular function and structure. The presence of obesity significantly affects hypertensive target organ involvement. On one hand, obesity may tend to mitigate the harmful effects of a chronically elevated total peripheral and renal vascular resistance and lessen end-organ damage such as nephrosclerosis in essential hypertension. However, since both obesity and hypertension increase cardiac workload, although by different mechanisms, their presence in the same patient results in a double burden to the left ventricle. Congestive heart failure, sudden death, and coronary heart disease are common sequelae of obesity hypertension. Weight loss reduces arterial pressure by a decrease in intravascular volume and cardiac output associated with a fall in sympathetic activity. Intervention in obesity hypertension diminishes the dual hemodynamic burden imposed on the heart and becomes therefore a major objective in the prevention and treatment of heart disease.

Adaptation, Physiological↗
PubMed1984

Hypertension and sudden death. Increased ventricular ectopic activity in left ventricular hypertrophy.

The present study was designed to detect and quantify cardiac arrhythmias in hypertensive patients with left ventricular hypertrophy. Continuous ambulatory electrocardiographic tracings and arterial pressure were recorded for 24 hours in 14 normotensive subjects, 10 patients with established essential hypertension without left ventricular hypertrophy, and 16 hypertensive patients with left ventricular hypertrophy by electrocardiographic criteria. Urinary excretion of norepinephrine was simultaneously measured over four successive four-hour and one eight-hour period. Patients with left ventricular hypertrophy had significantly more ventricular (but not atrial) premature contractions than those without left ventricular hypertrophy or than normotensive subjects. Five patients with left ventricular hypertrophy had episodes of more than 30 premature ventricular contractions per minute. Higher-grade ventricular ectopic activity such as coupled premature ventricular contractions was seen in two, and multifocal premature ventricular contractions were seen in three in the group with left ventricular hypertrophy. No difference in urinary catecholamine excretion rates among the three groups was seen. Left ventricular hypertrophy has been shown to be an independent risk factor for sudden death and acute myocardial infarction. Electrocardiographic monitoring of patients with left ventricular hypertrophy allows identification of those who have the highest risk and, therefore, require the most aggressive therapeutic intervention.

Adult↗
PubMed1984

Continuous noninvasive automatic blood pressure recording. Value and limitations in clinical practice.

In the experience reported here, continuous noninvasive automatic blood pressure recording, when used with Holter monitoring, has proved useful for evaluating the 24-hour blood pressure pattern in selected patients with hypertensive disorders and in those who suffer from syncope and hypotension. However, the high cost of the procedure and various equipment drawbacks limit its application. The method should probably be used only in specific clinical situations and in carefully selected patients.

Blood Pressure Determination↗
PubMed1984

Diurnal variation of blood pressure in elderly patients with essential hypertension.

Twenty-one elderly patients with essential hypertension, all over 65 years of age, were subjected to automated noninvasive 24-hour blood pressure measurement. Readings were obtained every 7.5 minutes throughout the day. The data were analyzed with respect to: correlation between office and ambulatory pressure measurements; possible differences in the circadian blood pressure pattern; and the existence of hypertensive or atherosclerotic cardiovascular complications. In all patients, the office systolic pressures were significantly higher than the ambulatory daytime pressures; diastolic pressures were similar. At night, two patterns of blood pressure emerged. In one there was a further fall in both systolic and diastolic pressures to normotensive levels, whereas the other pattern revealed no change in diastolic pressure, although systolic pressure increased significantly to similar levels as measured in the office. The prevalence of hypertensive or atherosclerotic cardiovascular complications in the patients with the first pattern was significantly less than in the group of patients with the second pattern (chi square, P less than 0.025). The data reported herein indicate that ambulatory blood pressure monitoring may help in the overall clinical evaluation of elderly patients with hypertension.

Aged↗
PubMed1984

Immediate hemodynamic effects of a dopamine-receptor agonist (fenoldopam) in patients with essential hypertension.

Systemic, splanchnic, and renal hemodynamics, intravascular volume, and reflexive and endocrine changes were measured before and after a single dose of fenoldopam, a novel antihypertensive agent that acts through stimulation of specific dopamine receptors. A 13% reduction in mean arterial pressure was mediated by a fall in total peripheral resistance association with an increase in cardiac index, heart rate, stroke volume, left ventricular ejection rate, and circumferential fiber shortening. Renal blood flow increased, thereby reducing the renal vascular resistance by more than 40%. In contrast, splanchnic hemodynamics failed to change. Likewise, there were no changes in intravascular volume, plasma renin activity, or norepinephrine, serum aldosterone, or prolactin levels.

Administration, Oral↗
PubMed1984

Pathophysiologic mechanisms in essential hypertension: a clue to the therapeutic approach.

Essential hypertension is not a homogeneous disorder. Distinct differences with regard to systemic hemodynamics, cardiac adaptation, and volumetric and humoral factors have been identified in various patient groups. Simple clinical clues allow us to identify three main underlying pathophysiologic mechanisms. The young, lean, white patient is characterized by an elevated cardiac output, normal total peripheral resistance, and increased activity of the sympathetic nervous system. The elderly hypertensive patient is characterized by a low cardiac output, left ventricular hypertrophy, high total peripheral resistance, contracted intravascular volume, low plasma renin activity, and target organ disease. The obese patient with essential hypertension presents with a high cardiac output, expanded intravascular volume, and a normal total peripheral resistance. Each of these three models represents one extreme of a wide, overlapping continuum. Identifying the underlying pathophysiologic mechanisms and matching them with the specific pharmacological properties of an appropriate antihypertensive agent should ensure greater patient acceptance and fewer adverse effects.

Adult↗
PubMed1984

Systemic and renal effects of enalapril and its effects on cardiac mass.

Enalapril is a new angiotensin converting enzyme (ACE) inhibitor and has been shown to be of benefit in the treatment of both renovascular and essential hypertension. We have studied the systemic and renal haemodynamic, biochemical and cardiac adaptive changes induced by this agent in eight patients with essential hypertension before and after 12 weeks of therapy. Mean arterial pressure fell from 110 to 90 mmHg (P less than 0.01) and this was mediated through a fall in total peripheral resistance, cardiac index and heart rate remaining unchanged. Renal plasma flow rose in six patients. Renal vascular resistance fell in all patients (P less than 0.01). Left ventricular mass index was reduced from a mean of 166 +/- 29 to 117 +/- 8 g/m2 (P less than 0.05) and systolic ventricular function remained unchanged. Thus, enalapril lowers arterial pressure by reducing total peripheral resistance, has favourable haemodynamic effects on the kidney, and produces a reduction in left ventricular mass within three months of the start of therapy.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1984

Clinical and hemodynamic determinants of left ventricular dimensions.

This study was designed to quantitate the influence of 20 clinical, hemodynamic, and volume determinants of left ventricular (LV) structure. Systemic hemodynamics, intravascular volume, and LV echocardiographic measurements were collected in a heterogeneous population of 171 patients. Stepwise multiple-regression analysis indicated that body weight and body-surface area were the most powerful determinants of LV chamber size, wall thickness, and muscle mass. Age, a pressure independent determinant of myocardial mass, had no influence on chamber size or LV function. Arterial pressure correlated best with the relative wall thickness and chamber volume. Intravascular volume was a major discriminator for chamber volume, LV mass, and velocity of circumferential fiber shortening. It is concluded that body weight, arterial pressure, intravascular volume, and age are each independent determinants of the LV dimension. Systolic pressure most closely correlated with relative wall thickness and thereby is the best predictor of degree of concentric LV hypertrophy.

Adolescent↗
PubMed1984

Greater renal vascular involvement in the black patient with essential hypertension. A comparison of systemic and renal hemodynamics in black and white patients.

Systemic, splanchnic, and renal hemodynamic data were derived from 60 male and female, black and white, untreated and uncomplicated patients with essential hypertension. The systemic hemodynamic data confirmed our previous findings that at any level of arterial pressure, when black and white patients are matched for age, sex, and mean arterial pressure, cardiac index and total peripheral resistance were similar. This suggests that hypertensive vascular disease is no more severe in the black. This concept was supported further with respect to the splanchnic vasculature; however, renal blood flow was less and renal vascular resistance was higher at any level of mean arterial pressure (or total peripheral resistance) in the black. These physiological findings lend credence to those reports suggesting that at any level of pressure, hypertensive disease and morbidity (e.g., renal impairment) are more severe in the black patient. In addition, these data underscore the importance of understanding regional circulatory characteristics and they do not necessarily follow pari passu measured indices of systemic hemodynamics.

Black People↗
PubMed1984

Stable red cell mass despite contracted plasma volume in men with essential hypertension.

Red blood cell mass, plasma volume, and renal and systemic hemodynamic measurements were evaluated in 24 normotensive men (group 1), 45 men with mild essential hypertension (group 2), and 43 men with moderate to severe essential hypertension (group 3). Despite significant hemodynamic differences between the groups and although plasma volume was contracted, the increased hematocrit in the third group of patients was not explained by an increase in red blood cell mass. Because this was the case in all groups, it demonstrates that the increased hematocrit in patients with more severe essential hypertension is solely attributable to the contracted plasma volume.

Adult↗
PubMed1983

Essential hypertension in the elderly: haemodynamics, intravascular volume, plasma renin activity, and circulating catecholamine levels.

In an attempt to dissociate the cardiovascular adaptations to high blood pressure from those of ageing, 30 patients with established essential hypertension aged over 65 years were matched for mean arterial pressure, race, sex, height, and weight with 30 patients younger than 42 years. Cardiac output, heart rate, stroke volume, intravascular volume, renal blood flow, and plasma renin activity were significantly lower in the elderly, whereas total peripheral (and renal vascular) resistance, left ventricular posterior wall and septal thicknesses, and left ventricular mass were higher. Intravascular volume correlated inversely with total peripheral resistance in both groups and in all patients. Pathophysiological findings of essential hypertension in the elderly are characterised by a hypertrophied heart of the concentric type with a low cardiac output resulting from a smaller stroke volume and a slower heart rate. Renal blood flow is disproportionally reduced and total peripheral and renal vascular resistance elevated.

Adult↗
PubMed1983

Pharmacologic and physiologic considerations of adrenoceptor blockade.

The beta-adrenergic receptor blocking drugs have been in use for the treatment of hypertension for almost two decades. Although the mechanism of their antihypertensive action still is not precisely known, they have become an established major class of therapy for the disease. Most agents produce an immediate reduction in heart rate and cardiac output, later followed by a reduction in pressure. The exceptions include: those agents that possess intrinsic sympathomimetic activity and produce little reduction in heart rate and output; and labetalol, an agent that reduces pressure immediately (associated with the cardiac effects) because it possesses alpha- as well as beta-adrenoceptor blocking effects. Just because a beta-blocking drug reduces cardiac output significantly, it does not follow that renal blood flow will decrease; this depends upon the number and affinity of receptors in the renal circulation. Most beta blockers (including labetalol) reduce renal vascular resistance in patients with uncomplicated hypertension. Other actions of this class of adrenoceptor blocking agents are discussed. As we learn more of the physiologic effects of adrenoceptor blocking agents, there is no doubt that we shall gain more insight into the underlying mechanisms of hypertensive diseases as well as their pharmacologic properties.

Adrenergic beta-Antagonists↗
PubMed1983

Clinical determinants and consequences of left ventricular hypertrophy.

The left ventricle adapts to an increased afterload such as that produced by arterial hypertension with concentric left ventricular hypertrophy. However, this adaptive process can be modified by a variety of physiologic and pathophysiologic states. Progressive aging, black race, and perhaps disorders with an increased sympathetic outflow seem to accelerate left ventricular hypertrophy. Obesity and other high cardiac output states predominantly produce dilatation of the left ventricle, and their combination with arterial hypertension results in eccentric left ventricular hypertrophy. Similarly, endurance exercise increases left ventricular volume more than wall thickness, whereas isometric exercise produces an increase in wall thickness only. The presence or absence of some physiologic and pathogenetic factors has direct implication on the assessment of what constitutes a "normal" left ventricular structure and function. Left ventricular hypertrophy has been shown to increase ventricular ectopic impulse generation and to put patients at a high risk of sudden death. Moreover, the increase in myocardial mass lowers coronary reserve and enhances cardiac oxygen requirements. Thus, the presence of left ventricular hypertrophy has to be considered as an ominous sign rather than as a benign adaptive process.

Aging↗
PubMed1983

Immediate hemodynamic effects of a new calcium-channel blocking agent (nitrendipine) in essential hypertension.

The immediate hemodynamic effects of a new calcium-channel blocking agent nitrendipine were studied in 12 patients with mild established essential hypertension. According to the response to mean arterial pressure, patients were classified into responders (decrease greater than 10 mm Hg, 7 patients) and nonresponders (less than or equal to 10 mm Hg, 5 patients). The decrease in arterial pressure in responders was associated with a significant (p less than 0.01) decrease in total peripheral resistance and a significant (p less than 0.05) increase in heart rate, cardiac index, and left ventricular ejection rate. The plasma norepinephrine level was significantly (p less than 0.05) increased in the responders. The response to upright tilt was qualitatively similar to pretreatment values. Thus, nitrendipine lowered arterial pressure as a result of arteriolar dilatation associated with a reflexive increase in heart rate and cardiac index. These hemodynamic properties make the drug particularly apt for use in combination with beta-adrenergic blockade for the treatment of arterial hypertension.

Adult↗