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Query: UMLS:C0085580 (essential hypertension)
 14,686 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Renal artery stenosis, either fibromuscular or atheromatous, is probably the most common cause of secondary hypertension in man. Both of these diseases are active, ongoing processes that may be ameliorated but not cured by medical or surgical treatment. The clinical history and examination of the patient with hypertension may help differentiate renovascular hypertension from essential hypertension. The presence of a systolic-diastolic or continuous bruit is often an indicator of severe renal artery stenosis. Systemic hypertension is the physiologic consequence of significant renal artery stenosis. Knowledge of the basic concepts of the renin-angiotensin-aldosterone system, as has evolved from experimental models of renovascular hypertension, forms the basis for understanding the process of evaluation and treatment of such patients. The treatment of choice for the patient with severe hypertension and a functionally significant renovascular lesion is surgical--both in terms of successful treatment of hypertension and improved long-term prognosis. Diligent periodic reevaluation of these patients as well as those with less severe hypertension who are receiving medical treatment enables the physician to select the proper management that offers optimal control of patient blood pressure and avoids target-organ damage to the kidneys, central nervous system, or cardiovascular system.
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PMID:Management of the patient with renovascular hypertension. 92 May 87

Mineralocorticoids are out of the causes of secondary hypertension. Excess production of mineralocorticoids induces sodium and fluid retention, loss of potassium and metabolic alcalosis. The diagnosis of mineralocorticoid syndromes depends on the interpretation of the functional status of the renin-mineralocorticoid-system, which is in part responsible for the maintenance of normal blood pressure. The classical representative of this group is the syndrome of primary aldosteronism. Causes of mineralocorticoid syndromes associated with hypertension are: 1. autonomous production of mineralo-corticoids by an adrenal adenoma or by idiopathic bilateral adrenal hyperplasia; 2. deficiency of adrenal 17-alpha-hydroxylase or of 11-beta-hydroxylase; 3. secondary aldosteronism associated with primary reninism, or renal arterial stenosis; and 4. pseudo aldosteronism due to excessive ingestion of licorice. Malign or essential hypertension may also often be followed by secondary aldosteronism.
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PMID:[Mineralocorticoid syndromes and hypertension]. 96 85

During the first 5 years of a community-based referral hypertension clinic, 331 ambulatory patients referred for diagnostic evaluation. Thirty-four patients were judged to be normotensive on the basis of resting blood pressures on 3 separate days. In 51 patients the diagnosis was borderline hypertension and 220, essential hypertension. Twenty-six patients (10.6%) had secondary hypertension. Twenty-one patients with secondary hypertension were first recognized from the data of the history, physical examination, and routine urinalysis. The main cost per patient of the initial and further evaluations was computed for each group of patients. The average cost to identify one case of secondary hypertension in the clinic was $2083. Because of the large problem with hypertension in the United States today, the cost-effectiveness of various approaches to the evaluation of patients with hypertension requires thoughtful reappraisal.
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PMID:Cost and yield of the hypertensive evaluation. Experience of a community-based referral clinic. 113 86

Previous attempts to assess sympathetic nervous system activity in patients with hypertension have used a variety of physiologic, pharmacologic and biochemical techniques. Results have been conflicting and confusing. Recently, the activity in plasma of the catecholamine synthesizing enzyme, dopamine-beta-hydroxylase (DBH), has been proposed as an index of sympathetic nervous system activity. Studies of apparently healthy subjects show that high values (greater than 60 units per liter) for plasma DBH activity correlate with pronounced daily lability of blood pressure and frequent readings greater than 130/85 mm of mercury. Studies of patients referred for evaluation of established hypertension show significantly higher values for plasma DBH activity in patients with primary hypertension than in those with commonly recognized forms of secondary hypertension-that is, renovascular, renal parenchymal and adrenocortical. Therefore, the measurement of plasma DBH activity may be helpful in the study and differential diagnosis of hypertensive diseases. Measurement of DBH in plasma is inexpensive, reproducible and relatively easy to do.
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PMID:Dopamine-beta-hydroxylase. An index of adrenergic function in hypertensive patients. 117 15

Elevated serum DBH (dopamine-beta-hydroxylase) activity was found in essential hypertension. The elevated level was not reduced when blood pressure was brought to normotensive level by administration of thiazide or rauwolfia. In contrast, serum DBH activity was low in both normotensive and hypertensive patients treated on prolonged hemodialysis. However, there was no correlation between serum DBH activity and blood pressure level. It was suggested that the pathogenesis of high blood pressure might be different between essential hypertension and hypertension with chronic renal failure, and that measurement of serum DBH activity might help for clinical differentiation of essential hypertension from certain forms of secondary hypertension.
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PMID:Serum dopamine-beta-hydroxylase activity in essential hypertension and in chronic renal failure with hypertension. 119 6

The lithium test was conducted to evaluate transport of water, sodium and osmotic active substances in 46 chronic glomerulonephritis (CG) patients. Sixteen CG patients entered group 1. All of them had secondary hypertension (SH). Twelve CG patients with SH symptoms of moderate reduction of endogenic creatinine clearance were assigned to group 2. Twelve patients of group 3 had CG and isolated urinary syndrome. Group 4 consisted of 6 patients with essential hypertension. As shown by the test, association of SH and CG is not an essential factor for renal transport of sodium, water and electrolytes. Some shifts in the transport in group 2 are attributed to reduced number of functioning nephrons. The tendency to enhanced lithium clearance was registered in group 4. This may reflect an increased supply of sodium, water and osmotic active substances to the uriniferous tubules.
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PMID:[The transport of sodium, water and active osmotic substances in different parts of the nephron of patients with chronic glomerulonephritis and hypertension]. 129 28

Angiotensin-converting enzyme (ACE) inhibitors are now widely used as first-line treatment of essential hypertension. Their effectiveness is potentiated by a low-salt diet and, above all, by the simultaneous prescription of diuretics. When secondary hypertension is suspected, ACE inhibitors are a good pharmacological tool to study the renin-angiotensin system. Since activation of this system is the main mechanism responsible for renovascular hypertension, ACE inhibitors are very useful for diagnosis. Conversely, blood pressure is not influenced by ACE inhibitors in primary hyperaldosteronism because of the low plasma renin and angiotensin II levels. Pheochromocytoma activates the renin-angiotensin system, and ACE inhibitors combined with beta-blockers enable the hypertension to be controlled prior to surgical treatment of the tumour. Finally, ACE inhibitors can be used to explore the renin-angiotensin system in the experimental model of renovascular hypertension and therefore contribute to our knowledge of the complex pathophysiology of this most frequent type of secondary hypertension.
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PMID:[Usefulness of converting enzyme inhibitors in the diagnosis of arterial hypertension]. 129 39

Study of intrarenal vasculature was carried out by using the metallic impregnation technique on whole kidney sections in 31 [corrected] cases of (primary and secondary) hypertension and 10 normal controls. Distinct patterns of intrarenal vasculature were noted in controls and in cases of hypertension. Gradual tapering of vessels, absence of tortuosity and good peripheral vascularisation were noted in controls. Abrupt tapering, tortuosity of vessels and poor peripheral vascularisation were noted in hypertensive cases. In essential hypertension moderate to severe changes of dilatation of the segmental and/or arcuate arteries was noted. The degree of dilatation was related to the level of systolic BP rather than diastolic in cases of essential hypertension. Secondary hypertension even if severe, rarely showed significant dilatation lesions. Avascular zones and conglomeration of vessels at poles was seen only in cases of pyelonephritis. This helped in distinguishing these, from cases of glomerulonephritis.
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PMID:Study of intrarenal vasculature in cases of primary and secondary hypertension (by metallic impregnation technique on whole kidney section) 130 86

Circadian blood pressure rhythm exhibits a typical biphasic pattern in normotensives and in patients with primary hypertension. It is, however, disturbed in patients with secondary hypertension. There is ample evidence suggesting a major role for the sympatho-adrenergic system in regulating this rhythm. In order to investigate this relationship more accurately, the sympatho-adrenergic activity was studied in 20 patients with normal blood pressure, 20 patients with primary hypertension, and in patients with several diseases characterized by an abnormal catecholamine secretion, e.g. two pheochromocytomas, one adrenomedullary hyperplasia, and two Shy-Drager syndromes. Catecholamine concentrations were measured in plasma and urine, cAMP concentrations in plasma or in lymphocytes, and beta-adrenoceptor density and affinity on lymphocytes, and 24-h blood pressure monitoring was conducted. The data shows synchronicity of the circadian blood pressure rhythm and the sympatho-adrenergic activity both in normotensives and in patients with primary hypertension with normal circadian rhythm, and in abnormal catecholamine secretion with an abnormal circadian blood pressure curve. It is concluded that sympatho-adrenergic mechanisms play an important role in controlling and regulating circadian blood pressure.
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PMID:[Synchronized circadian blood pressure rhythm and sympatho-adrenergic activity]. 132 91

Although essential arterial hypertension is believed to have a strong genetic predisposition, the gene(s) responsible are unknown. The mechanisms underlying the regulation of blood pressure and experimental studies place the renin gene among the main candidate genes that need to be tested in humans. We tested the hypothesis of a linkage between the renin gene and essential hypertension using the affected sib pair method. Siblings (133 subjects, 52.1 +/- 10.9 years) from 57 families were selected for sustained hypertension (160.7 +/- 22.9/99.5 +/- 12.8 mmHg with 80% of patients under antihypertensive treatment), of early onset (40.7 +/- 12.0 years), in the absence of obesity, diabetes mellitus, and secondary hypertension. Eight renin haplotypes were generated from three diallelic renin restriction fragment length polymorphisms (RFLPs) (TaqI, HinfI, HindIII) located throughout the renin gene. The allelic concordance between the sib pairs was analyzed by identity by state relationships for 98 sib pairs (41 for 41 couples, 39 for 13 trios, 18 for 3 quartets). Allelic frequencies in the 57 hypertensive probands were similar to those observed among 102 hypertensive subjects studied previously. Six of eight possible haplotypes were observed, the informativity of the marker corresponded to 70% of heterozygosity. Allelic concordance for all sib pairs according to sibship size was not significantly different from that expected under the hypothesis of no linkage (t = 0.52, P = 0.15) reflecting only a small excess of renin alleles shared by the hypertensive sibs (1.44 +/- 0.6 vs 1.36 +/- 0.6). Likewise the linkage hypothesis was unsupported by weighted estimates to correct for possible bias due to large sibship size. Thus, the sib pair analysis suggests that the renin gene does not have a frequent role in the pathogenesis of essential hypertension; further more powerful linkage studies or other approaches will be needed to detect contributions at the renin locus to the heritability of essential hypertension.
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PMID:Sib pair linkage analysis of renin gene haplotypes in human essential hypertension. 134 86


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