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

Despite recognized limitations, the renal vein renin ratio (RVRR) remains the most commonly used index of surgical curability in hypertensive patients with renal artery stenosis. It is generally held that a ratio exceeding 1.5 forecasts a favorable response to surgery. Measurement of this ratio in 40 patients with essential hypertension (no arteriographically demonstrated stenosis) showed 8 (20%) with RVRR over 1.5, confirming an overlap of this ratio between patients with essential and renovascular hypertension. Intra-arterial injection of contrast material influenced renal vein renin activity (RVRA) in some individuals, but we were unable to demonstrate significant alterations in the group as a whole. Since the influence of intra-arterial contrast material on RVRA is variable and unpredictable, it appears unwise to collect renal venous blood for renin measurements soon after angiography.
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PMID:Renal vein renin activity in primary hypertension: variability and influence of contrast material. 91 86

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

The effect of propranolol therapy on the mean arterial pressure (MAP) and plasma renin activity (PRA) was studied in three groups of hypertensive patients who were also treated with saliuretics. Group A: In 14 patients with essential hypertension on chlorthalidone treatment, an additional daily dose of 640 mg propranolol for two months led to a significant reduction of the MAP (from 124 to 105 mm Hg) and PRA (from 5.3 to 2.0 ng AI/ml/hr standing). There was no correlation between MAP reduction and either the original levels or change in PRA. Group B: In 14 patients with essential hypertension and 5 with renal artery stenosis studied on a fixed salt intake, the plasma and extracellular volumes, PRA, and blood pressures were recorded before and after three days of diuretic induced salt depletion and, with maintenance of the depleted state, after three days of propranolol. Salt depletion resulted in a decrease in MAP from 132 to 128 mm Hg (NS), and PRA increased from 3.4 to 22.3 ng AI/ml/hr (P less than 0.01). There was no correlation between change in MAP and PRA control values, PRA change, or any of the volume parameters. Addition of propranolol was followed by a rapid MAP decrease to 111 mm Hg (P less than 0.01), and the PRA dropped to a mean of 8.5 (P less than 0.01). No correlation was found between change in MAP and change in PRA. The patients with renal artery stenosis did not differ in their reactions from those with essential hypertension. Group C: In five patients with moderate renal failure and normal to expanded 82-Br distribution volume, propranolol lowered MAP by 10% and lowered the PRA in all five. Salt depletion by furosemide to 82-Br volumes below normal resulted in a 10% decrease of MAP and a marked rise in PRA. In this state propranolol was followed by a further MAP reduction of 18% and a decrease in PRA. There was no quantitative relationship between MAP and PRA change during either of the treatment regimes. It is concluded that in various forms of hypertension, the blood pressure can be effectively lowered by combining diuretics and propranolol regardless of the pretreatment PRA level.
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PMID:Effect of salt depletion and propranolol on blood pressure and plasma renin activity in various forms of hypertension. 109 56

The review discusses the pathophysiology of the renal mechanisms of blood-pressure control. The physiology of the renin-angiotensin system is described and the mineralo-corticoid function has also been considered. The implications of alterations of these systems in various nephropathies are briefly summarized (renal artery stenosis, infarction, Page's syndrome, acute glomerulonephritis, essential hypertension a.o.).
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PMID:[Pathophysiology of renal hypertension (author's transl)]. 110 Dec 91

In a series comprising 482 patients with hypertension requiring treatment 79 percent had to be classified as essential hypertension. Bilateral renal disease was found in 9 percent, unilateral renal disease in 3.3 percent, but only one patient underwent surgery. Renal artery stenosis was found in 24 patients (5 percent), but only 5 (1 percent) were operated on. Two cases of primary hyperaldosteronism and one of phaeochromocytoma were found; in all three surgical intervention was successful. Oral contraceptives had caused the elevated BP in 7 patients (1.5 percent). It is emphasized that the frequency of curable hypertension is still very low and this should be taken into account when routine examination of patients with hypertension requiring treatment is discussed.
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PMID:The frequency of secondary hypertension. 112 62

Renal venous and peripheral plasma renin activities were determined in 29 operated patients with renovascular hypertension and in 10 patients with essential hypertension. The majority of patients with renovascular hypertension exhibited elevated peripheral plasma renin activity, but the most striking increase of renin activity was demonstrated in the venous effluent of the involved kidney. Using data obtained in patients with essential hypertension, the ratio of renal vein renin activity not exceeding 1.4 was assumed normal. In patients with renovascular hypertension, the values above 1.4 were accepted as lateralizing ratios. In 78.6 % of patients with unilateral renal artery stenosis and a lateralizing renal vein renin ratio, normotension or improvement of blood pressure control were obtained post-operatively. The discussion emphasis the importances of renal vein renin estimations with the calculation of renal vein ratio for determining the functional significance of renal artery stenosis and for predicting the surgical outcome
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PMID:Renal venous renin in patients with renovascular hypertension. 114 58

Renal vein renin ratios from 56 hypertensive patients who were operated upon for unilateral stenosis of a main renal artery were compared to blood pressure response to a corrective operation. In patients with renal vein renin ratios greater then 2.0, the upper limits of normal for essential hypertension (95 per cent confidence limits), the cure/improvement rate approximated 90 per cent. However, in patients operated upon despite lesser ratios the cure/improvement rate was also high--83 per cent in our series and 57 per cent in collected reports from the literature. Thus, the test may be falsely negative in a high percentage of patients. Renal vein renin ratios would appear to be most useful in confirming but not necessarily in denying the functional significance of a renal artery stenosis.
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PMID:Renovascular hypertension: does the renal vein renin ratio predict operative results? 126 7

Renography with [99mTc] diethylenetriaminepenta-acetate (DTPA) was performed in 26 patients with renal artery stenosis (RAS), unilateral in 15 and bilateral in 11, and in 16 patients with essential hypertension with a normal renal angiogram. Nine of the patients with unilateral RAS were restudied after a successful percutaneous transluminal renal angioplasty (PTRA), i.e. complete removal of the stenosis and a normalization of the blood pressure without antihypertensive treatment. Single-kidney [99mTc]-DTPA clearance and parenchymal mean transit time (MTT) were determined at each examination. All patients were studied on two different days using the same procedure except that captopril 25 mg was given orally before renography at the second examination. In unilateral RAS captopril reduced single-kidney [99mTc]-DTPA clearance significantly on the affected side (-42.7%, median) but not on the unaffected side (-3.2%). In bilateral RAS single-kidney [99mTc]-DTPA clearance was reduced to the greatest extent on the most affected side (-43.0%) compared with the least affected side (-17.2%). In essential hypertension no significant changes were recorded on any side (-1.5% for both). After PTRA, single-kidney [99mTc]-DTPA clearance was not significantly changed by captopril either on the previously affected side (4.3%) or on the unaffected side. MTT was significantly prolonged after captopril on the affected side in unilateral RAS and on the most affected side in bilateral RAS, whereas no significant changes were found on the unaffected side in unilateral RAS, on the least affected side in bilateral RAS, or on any side in essential hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Angiotensin-converting enzyme inhibitor renography in the diagnosis of renovascular hypertension. Studies before and after angioplasty. 133 56

The effectiveness of single-dose captopril test (CP-T) and captopril renal scintigraphy with 99mTc-DTPA (CP-RG) in the diagnosis of renovascular hypertension (RVH) was evaluated in 27 patients with (Group I, 16 patients) or without (Group II, 11 patients) renal vascular disease. Group I consisted of RVH in 8 patients (bilateral in 3, unilateral in 5), arteriovenous malformation in 3, renal artery aneurysm in 4, including 2 with essential hypertension, and asymptomatic renal artery stenosis in 1. Group II consisted of 6 hypertensive patients (2 with essential hypertension and 4 with renal hypertension) and 5 normotensive patients. Sensitivity of CP-T and CP-RG in the diagnosis of RVH was 29% (2/7) and 86% (6/7), respectively, indicating the latter was more sensitive than the former. In 3 patients with bilateral RVH, positive response in CP-RG was observed only in the unilateral kidney. Specificity of CP-T and CP-RG was 86% (6/7) and 100% (5/5), respectively in Group I, 100% (8/8) and 83% (5/6), respectively in 16 hypertensive patients. CP-T and CP-RG before and after the treatment of RVH were evaluated in 4 patients. The change of positive response in CP-T and CP-RG into negative after percutaneous transluminal renal angioplasty (PTA) or surgery were found in 3, all followed by a fall in blood pressure, which was not observed in the other patient with positive response after PTA.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Single-dose captopril test and captopril renal scintigraphy in the evaluation of renovascular hypertension]. 143 70

Patients (pts) with essential hypertension normally exhibit a typical diurnal variation with a nocturnal blood-pressure (BP) decreased. A lack of this periodicity is often reported in pts with secondary hypertension. 24-h BP measurement was therefore performed in 308 pts with essential hypertension, and in 172 pts with secondary hypertension, in order to evaluate the diagnostic value of nocturnal BP decrease. Diagnoses of the secondary hypertensives were: renoparenchymatous hypertension (n = 29), diabetic nephropathy (n = 24), morbus Conn (n = 6), renal artery stenosis (n = 32), pheochromocytoma (n = 5), hemodialysis pts (n = 30), and kidney transplantation (n = 44). Pts with essential hypertension showed a mean systolic and diastolic BP decrease during the nighttime period of 22 +/- 7 mmHg and 17 +/- 5 mmHg, respectively. In contrast, the corresponding values in secondary hypertension were 5.7 +/- 9.2 mmHg (systolic decrease) and 5.2 +/- 5.9 (diastolic decrease). Pts with pheochromocytoma who had a nighttime increase in BP demonstrated the greatest difference from the essential hypertensives, followed by pts with either diabetic nephropathy or after kidney transplantation. A lack of nocturnal BP decline (less than 10% of the daytime values) was detected in 69.8% of pts with secondary hypertension, but only in 5.2% of pts with essential hypertension. In summary, these results suggest that the absence of a nighttime decline in BP during 24-h ambulatory monitoring is an indication of secondary hypertension and should lead to further investigations. Furthermore, a nightly hypertension is associated with a higher risk of complications.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Diagnostic significance of absent nocturnal blood pressure decrease in 24-hour long-term blood pressure measurement]. 151 20


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