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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pheochromocytoma is an infrequent cause of hypertension. In spite of its rarity, pheochromocytoma has assumed notorious importance because or a wide variety of clinical features associated with this syndrome. Hypertension remains the most important clinical lead. The presence of other features, such as severe headache, perspiration, palpitations or orthostatic hypotension, makes the diagnosis of pheochromocytoma likely. The diagnosis of this condition can be made with greater certainty than that of any other form of secondary hypertension. Pharmacologic tests are no longer used for evaluation purposes. Biochemical tests are the most important aids to diagnosis, provided highly specific methods are used to determine the levels of urinary catecholamines or their metabolites. Interference by various drugs should be avoided. Most of the pheochromocytomas are found in the abdomen, predominantly in the adrenals. Successful outcome of surgery depends critically on adequate preoperative preparation of the patient with adrenergic blocking drugs and proper intraoperative care. Surgery should only be performed in an institution with experience in treating these tumors. Invasive localizing procedures could be dangerous in patients with pheochromocytoma and are best avoided. Medical therapy proves to be quite successful for those patients who are unable or unwilling to undergo surgery and for those with demonstrated malignant tumor. The postoperative course in most instances is uneventful. The physician should be aware of familial forms of pheochromocytomas and screen all the hypertensive members of the patient's family for the presence of this condition. Pheochromocytoma, with its multiple facets, presents a challenge to the clinician; however, with prompt diagnosis and proper treatment, pheochromocytoma can often be cured. The improved management of patients with this potentially lethal condition is the result of better knowledge of biochemical pharmacology, improved preoperative, surgical and postoperative care.
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PMID:Pheochromocytoma--recognition and management. 4 12

Of 15 594 high school students (ages, 15 to 20) whose blood pressure was measured in a screening program, 350 (2.2%) has hypertensive readings (150 mm Hg or more systolic, or 95 mm Hg or more diastolic, or both). The mean blood pressure for the boys was 125.0 plus or minus 12.1/71.8 plus or minus 10.9 mm Hg, and for the girls, 119.8 plus or minus 10.2/72.3 plus or minus 9.2 mm Hg. The parents of the students with hypertensive readings were advised to send their children to a physician. By 6 months, of the 232 who were followed up, 156 (67.2%) has visited a physician and in 19 cases (12.2%) the physician had confirmed the hypertensive readings. Only one student, an asymptomatic 17-year-old boy whose hypertension had not previously been detected, was found to have secondary hypertension, which was relieved surgically. Of the 18 hypertensive students 4 are currently receiving antihypertensive medication and 8 continue to have their blood pressure monitored. The mean blood pressures recorded in the physicians' offices averaged 23.7/11.1 mm Hg less than those recorded in the schools. One reason for this was that none of the physicians used pediatric cuffs, but these were required by 62.4% of the students at the screening. Hence, the intravascular blood pressure was probably underestimated in a number of cases in the physicians' offices.
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PMID:Screening for hypertension in a high school population. 12 24

The validity and usefulness of the ECG criteria of left heart hypertrophy according to Sokolow and Lyon were tested in 54 hypertensive children and adolescents. Among them, there were 9 children with secondary hypertension of known origin, and 45 adolescents with labile juvenile hypertension due to hyperkinetic heart activity. Only in 21 (38%) patients were present positive ECG criteria of hypertrophy. In view of the fact that between 8 and 16 years of age the R and S voltage in left precordial leads in normal adolescents exceeds the voltage limits of these criteria in adults, the validity of criteria is discussed. It is postulated that the investigated criteria lose their validity in the given age group because of the age differences in the ECG patterns. An ECG diagnosis of cardiac hypertrophy can be made only when more than two positive criteria are present together with a clinical evidence of enlarged heart. If only one or two voltage criteria are present, it is advisable to interpret this as an ECG manifestation of left heart systolic overload and to use it only as auxiliary sign for further follow-up of the patient.
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PMID:The clinical interpretation of electrocardiogram in hypertensive children and adolescents. 15 Mar 22

221 patients with arterial hypertension were investigated as outpatients. 198 patients were found to have primary and 23 patients to have secondary hypertension. The results of urinary analysis were pathological in 25% of patients and renal function tests were abnormal in 20% of cases. Significant bacteriuria was recorded in 19% of urinary cultures. Intravenous pyelography showed true pathological findings in 12% of cases, false positive findings in 7% and false negative findings in 5%. Isotopic nephrograms showed true positive findings in 52%, false negative in 3% and 45% showed normal results. In 53% of patients angiography of the kidneys showed normal results, whilst this investigation proved pathological in 44% of cases and gave false negative results in 3% of patients. An additional search for coronary heart disease risk factors revealed that 73% of these hypertensive patients were overweight, 47% had hyperlipidaemia, 33% suffered from diabetes mellitus and nicotine abuse was present in 21% of cases. A relevant yet inexpensive screening programme for the investigation of hypertension is formulated on the basis of the results of this investigation.
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PMID:[The value of different investigation procedures in arterial hypertension (author's transl)]. 15 88

Renin-aldosterone profiling was used to classify patients with hypertension: 243 patients with essential hypertension were classified by renin-urinary sodium indexing; 107 were reclassified by response to administration of furosemide and intravenous saline; 45 were further classified by response to a low-sodium diet. Arbitrary "normal ranges" were determined in 89, 32, and 38 volunteers, respectively. Patients with low-renin apparently do not have "high-volume" hypertension. Rather, they show a primary renal abnormality in renin secretion and become relatively deficient in angiotensin II and aldosterone when they are subjected to diuresis. They can maintain aldosterone secretion under normal conditions because their adrenal aldosterone receptor is supersensitive to angiotensin II. No evidence of abnormal sympathetic neural activity was found among the renin subgroups. Renin-aldosterone profiling in current clinical practice seems useful mainly in the detection of patients with curable forms of secondary hypertension. Aldosterone/renin ratios may be particularly helpful in diagnosis when obtained after a patient has undergone expansion or contraction of his extracellular fluid volume.
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PMID:Renin-aldosterone profiling in hypertension. 33 42

The recognition of secondary causes of hypertension, such as renovascular disease and aldosteronism, can be enhanced by stimulation and suppression of the 2 limbs of the renin angiotensin system. Normal values have been established in unstimulated and stimulated conditions. Saline infusion suppresses plasma aldosterone normally. Patients with proved adenomas do no suppress renin and are outside the well established ranges of normal suppression. Likewise, furosemide will stimulate renin release. Patients with proved aldosteronism are outside the normal ranges of plasma renin activity. These maneuvers also are useful in discriminating renovascular hypertension, particularly when achieving differential renal venous collections under stimulated conditions (after furosemide and tilting). By stressing this system (with furosemide stimulation or saline suppression) one can discriminate better secondary hypertension by the failure to respond normally.
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PMID:Evaluation of patients for secondary hypertension. 39 53

To test whether central neurogenic factors participate in blood pressure elevation in primary hypertension, we studied the concentrations of: norepinephrine, epinephrine and dopamine-beta-hydroxylase (DBH) in cerebrospinal fluid (CSF); and norepinephrine, epinephrine, DBH and plasma renin activity (PRA) in plasma of 22 subjects (seven with primary hypertension, 11 normotensive patients with non-systemic neurological disorders, and four with secondary hypertension). Plasma and CSF norepinephrine (NE) were increased in primary hypertensives compared to normotensives. Cerebrospinal fluid norepinephrine was related to diastolic blood pressure, and systolic blood pressure when normotensive and primary hypertensives were taken together. The CSF norepinephrine of primary hypertensive patients was correlated with natural log PRA. The CSF norepinephrine was correlated inversely with age in primary hypertensive patients but not in the normotensive subjects. The low CSF norepinephrine and epinephrine, despite markedly increased plasma NE and epinephrine, in two patients with pheochromocytoma, indicate a blood-brain barrier for these neurohormones. The observations support the view that the central sympathetic nervous system is involved in the pathogenesis of primary hypertension, particularly in younger patients.
Hypertension
PMID:Raised cerebrospinal fluid norepinephrine in some patients with primary hypertension. 39 37

Two hundred and eighty-two (282) patients suffering from hypertension were evaluated for the detection of secondary forms of hypertension. Apart from clinical and routine laboratroy investigation in each, straight film of abdomen, intravenous pyelography (IVP), isotope renography and aortography were done in 174, 51, 109 and 2 cases respectively. Evidences of secondary hypertension was present in 22(7.8%) of which renal aetiology was probable in all but 4. Of the 10 patients with a primary kidney condition, possible renal aetiology was unsuspected in only one patient with unilateral renal hypoplasia. In 8 patients with renal involvement due to systemic disease, or in 4 with non-renal causes, the aetiological diagnosis was suggested by the clinical situation. In view of low yield of curable hypertension and high cost, IVP and renography should only be employed selectively and not as routine investigations.
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PMID:Diagnostic evaluation of hypertension: pilot study in a hypertension clinic. 41 57

The comprehensive diagnostic evaluation once recommended for hypertension is no longer practical or necessary. In the majority of cases, a thorough history, physical examination, and basic laboratory workup are sufficient to determine the severity of the hypertension and to detect target organ damage. Secondary hypertension is truly rare in clinical practice and should not be pursued with complex, costly, and possibly risky tests unless specific indications are present.
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PMID:Practical approach to hypertension. 1. Diagnostic evaluation. 43 61

Severity of hypertension, frequency of secondary hypertension and prognosis have been compared in two groups of hypertensive men. The first group (n=686) was taken from a blood pressure screening of a total population sample. The other group (n=154) consisted of hypertensive men, referred to a hypertension clinic by physicians. The mean age of the groups was the same, (X=52 years, range 46--59 years). All went through the same investigations and were followed up and treated in a similar way at the hypertension clinic. The referred men had more severe hypertension, as shown by significantly more heart and kidney involvements. They also had a higher incidence of myocardial infarction, implying a poorer prognosis with regard to cardiovascular disease. The analysis shows the importance of a detailed description of studied groups, not only in terms of blood pressure, age and sex, but also with respect to the frequency and degree of present and previous signs of heart and kidney involvement. With such a description it is possible to compare results from different studies regarding pathophysiological mechanisms and the effect of treatment in hypertension.
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PMID:Heart and kidney involvement and prognosis in hypertension. A study concerning referred hypertensive patients and hypertensive patients found by blood pressure screening. 47 82


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