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Background/aim: Scarce data exist concerning the long-term effect of renal balloon angioplasty (PTRA) enhanced by intravascular gamma-brachytherapy (IVBT) in patients with renovascular hypertension. The aim of this randomized study was to evaluate long-term outcome after PTRA with IVBT in patients with renal artery stenosis., Patients and Methods: 71 patients with renovascular hypertension were randomized into group I (PTRA + IVBT) or group II (PTRA). 9 patients who required stent implantation were excluded. Both baseline and 9-month follow-up quantitative computerized angiography and intravascular ultrasound (IVUS) analysis were performed to assess restenosis. During the 9-month follow-up, 3 patients died - 2 from group I and 1 from group II., Results: The restenosis rate was 16.1% in group I and 32.1% in group II. The 9-month lumen loss in angiography was 1.2 +/- 0.7 and 1.7 +/- 0.7 mm (p = 0.004) and the area loss (IVUS) was 6.5 +/- 4.8 and 10.1 +/- 5.6 mm(2) in groups I and II, respectively (p = 0.01). eGFR increased both in group I (from 75 +/- 22 to 84 +/- 31 ml/min/1.73 m(2); p < 0.001) and in group II (from 74 +/- 23 to 77 +/- 23 ml/min/1.73 m(2); p = 0.04). Only the diastolic blood pressure in group I decreased significantly (65 +/- 17 and 77 +/- 18 mm Hg; p = 0.048). The rate of blood pressure normalization was low in both groups (6.1 and 6.9%)., Conclusions: IVBT after PTRA with a self-centering source is a safe and effective method for prevention of restenosis in patients with renovascular hypertension., (Copyright 2008 S. Karger AG, Basel.)

Background: Patients with renovascular hypertension (RVH) have a higher degree of cardiovascular end-organ damage compared to patients with essential hypertension (EH). The precise mechanisms underlying this phenomenon, however, have not been fully elucidated. This study investigated the relationship between circadian blood pressure (BP) profile and cardiac involvement in patients with RVH and EH., Methods: Twenty patients with RVH and 20 with EH, matched for demographic characteristics, underwent simultaneous 24-hour ambulatory BP recording and Holter ECG monitoring. Also, each participant underwent echocardiographic assessment of left ventricular mass. Cardiac damage was defined as the presence of left ventricular hypertrophy, myocardial ischemia or arrhythmias., Results: Casual BP was similar in both groups, whereas 24-hour ambulatory BP values were higher in RVH than in EH patients; moreover, RVH patients had higher blood pressure variability and blunted nocturnal BP fall compared to those with EH. Left ventricular mass, as well as the prevalence of myocardial ischemia and the presence and severity of cardiac arrhythmias, were higher in RVH than in EH patients., Conclusions: Patients with RVH have altered circadian BP profile compared to those with EH. This abnormality might contribute to their increased prevalence of cardiac damage and might adversely affect the prognosis of these patients.

Background: Atherosclerotic renovascular disease is a frequent cause of end-stage renal failure leading to dialysis in the elderly population. Its prevalence is known from autopsy or retrospective arteriographic investigations. This prospective study was conducted in 133 subjects with the inclusion criteria of hypertension and/or chronic renal failure starting after 50 years of age. Renal failure was unrelated to other known causes of renal disease., Methods: The patients were subjected to echo-color doppler ultrasonography of renal arteries (104) and/or to renal scintigraphy (112). Thirteen of 27 patients with positivity using one or both noninvasive techniques were subjected to digital selective angiography., Results: All the patients with positivity of echo-color doppler technique were true positives, with a consequent predictive value reaching 100%. Renal scintigraphy was of markedly lower predictive value. Based on the echo-color doppler investigation, percentage positivity for hemodynamically significant stenosis (> 50%) was 3.2 (16.3% had mild nonsignificant stenosis of renal arteries) in the 50- to 59-year-old group, 20% (plus 12.5% with nonsignificant stenosis) in the 60- to 69-year-old group and 25% (plus 17.8% nonsignificant stenosis) in the > 70-year age group. Patients with significant stenosis also had a significantly higher degree of renal insufficiency and received a higher number of hypotensive drugs (p < 0.013). The percentage of hypertensive patients was not different in the stenotic and nonstenotic groups., Conclusions: A large percentage of the elderly population is affected by renal vascular obstructive disease and is at risk of developing end-stage renal failure. Considering the wide number of cases with foreseeable renal arterial stenosis in the vast population meeting the selection criteria, it is possible to conclude that not all cases evolve to renal failure due to different rates of progression or to untimely nonrenal death.

Two boys, 11 and 10 years of age, respectively, having renovascular hypertension are reported. Diagnostically, captopril test and renal scintigraphy were useful as pharmacologic probes of the renal arterial stenosis and to determine its laterality, as well for examination of the operative outcome. Both children were rendered normotensive after renal revascularization, one by renal autotransplantation and the other by aortorenal bypass procedure. Renovascular hypertension in children is also discussed.

Plasma endothelin-1 (ET-1)-like immunoreactivity in selective renal venous blood and peripheral venous blood was measured and compared with plasma renin activity and aldosterone level in a 26-year-old woman with suspected renovascular hypertension due to stenosis of the left renal artery. Although there was no significant step-up in plasma renin activity between the right and the left renal vein, left/right ratio of plasma ET-1 in the renal vein was 2.18. This case suggests that ET-1 may be one of the hypertensive mechanisms of suspected renovascular hypertension in addition to the renin-angiotensin system.

We report a 2-year-old boy with renovascular hypertension caused by stenosis of the left renal artery that was successfully treated by percutaneous transluminal angioplasty (PTA). He initially presented with severe hyponatremia, hypokalemia, polyuria, transient proteinuria and weight loss. This phenomenon is known to occur in patients with renovascular and malignant hypertension, called hyponatremia hypertensive syndrome, but was thought to be rare in children. Renovascular hypertension should be considered as a cause of hyponatremia in children. In addition, PTA is an appropriate treatment even in very young children with renovascular hypertension.

The captopril test was performed on 49 children of whom 36 were hypertensive, and the remainder were normotensive but were at risk for developing hypertension because of scarred kidneys secondary to vesico-ureteral reflux. Blood pressure (BP) was monitored in fasting supine patients throughout the duration of the test. Blood was taken for measurement of plasma renin activity (PRA); then captopril (0.7 mg/kg of body weight) was administered orally. A second blood sample was taken for PRA at 90 min postcaptopril. The mean (SEM) PRA at 90 min was 11.90 (4.01) ng/l/s [42.84 (14.44) ng/ml/h] in 7 patients with renovascular disease. In 4 patients with essential hypertension corresponding values were 0.88 (0.38) ng/l/s [3.17 (1.37) ng/ml/h]. Patients with other renal diseases showed variable values. Some individuals had PRA values as high as those of patients with renovascular disease, but the etiology of their hypertension was usually clinically evident. Our preliminary data would suggest that the captopril test may help differentiate between patients with essential hypertension and those with renovascular disease, or may help select patients that should be followed up by more definitive diagnostic procedures.

The captopril test was performed in 49 children of whom 36 were hypertensive, and the remainder were normotensive but at risk for developing hypertension because of scarred kidneys secondary to vesicoureteral reflux. The blood pressure was monitored in fasting supine patients throughout the duration of the test. Blood was taken for measurement of plasma renin activity (PRA), then captopril (0.7 mg/kg body weight) was administered orally. A second blood sample was taken for PRA measurement 90 min after captopril administration. The mean PRA at 90 min was 11.90 +/- (SEM) 4.01 ng/l/s (42.84 +/- 14.44 ng/ml/h) in 7 patients with renovascular disease. In 4 patients with essential hypertension, the corresponding value was 0.88 +/- 0.38 ng/l/s (3.17 +/- 1.37 ng/ml/h). Patients with other renal diseases showed variable values. Some individuals had PRA values as high as those of patients with renovascular disease, but the etiology of their hypertension was usually clinically evident. Our preliminary data would suggest that the captopril test may help differentiate between patients with essential hypertension and those with renovascular disease or may help select patients that should be followed up by more definitive diagnostic procedures.

A unique case of renovascular hypertension in an asymptomatic, microhematuric 61/2-year-old girl is presented. Abdominal ultrasonographic (UT) and computed tomographic (CT) studies, splenic and renal radionuclide evaluations revealed that a 'boomerang'-shaped spleen, anterior and medial to the left kidney, compressed and flattened its upper pole. Arteriography excluded stenosis of the renal arterial vessels. Renal vein renin ratio of 1.78 and contralateral/caval ratio of 1.13 eventually demonstrated that hypertension was caused by a lateralized renin hypersecretion from the compressed upper pole through left superior and central renal veins. Overactivity of the renin/angiotensin system was presumably due to ischemia of the renal parenchyma extrinsically compressed by the spleen.

A case of Ask-Upmark kidney with coexistent contralateral renal artery fibromuscular dysplasia is presented with detailed light and electron microscopic findings. Both lesions are known to produce renin-mediated hypertension which was corrected in this patient by nephrectomy and contralateral renal artery bypass. Ask-Upmark kidney is briefly reviewed.

The diagnostic accuracy of renal vein renin (RVR) analyses was evaluated in 63 hypertensive patients treated with sodium depletion and/or hydralazine prior to selective renal vein sampling. A positive RVR study (i.e., lateralization of RVR) was defined as a ratio greater than or equal to 1.5 when RVR from the kidney with renal artery stenosis was compared to RVR from the contralateral kidney. Approximately 40% of patients with essential hypertension had positive RVR studies. Among patients with renal artery stenosis, surgical outcome was correctly predicted in 5 of 8 patients (63%) treated with sodium depletion, whereas outcome was accurately predicted in 11 of 12 patients (92%) treated with hydralazine. These observations demonstrate that a high percentage of patients with essential hypertension have positive RVR studies despite arteriographically normal renal vasculature. Results obtained in patients with renal artery stenosis suggest that stimulation of renin secretion by hydralazine may be of particular advantage prior to renal vein sampling. However, additional data are required to confirm whether activation of specific mechanisms for renin release improves the reliability of the RVR test.

Effective drug therapy for hypertension modifies the urgency of establishing a diagnosis of renal arterial stenosis. The cost of establishing a diagnosis must be considered with other factors in determining the usefulness of renography in renovascular hypertension. Recently published studies estimate the cost effectiveness of this procedure based on some data from a cooperative study of renal vascular hypertension. The small but costly incidence of false positives contributes significantly to the total cost of patient screening. Careful attention to technical details that are presented here could reduce false positives without sacrificing the true positives. However, even with increased specificity economic considerations would indicate limiting a screening program to younger patients or those in whom a drug regimen is unsuccessful.

Due to better methods of diagnosis, an increasing number of children with renovascular hypertension are being discovered. The disease itself has variable clinical manifestations, and an adequate laboratorial workup, including arteriography and renin assays, is mandatory in suspected cases. Treatment depends on the prognostic values of the renin assays and surgery cures 80% of the patients, either by nephrectomy or by revascularization techniques. Among these, renal autotransplantation gives better exposure of the operative field, and therefore better results. In most cases, systemic infection seems to be the main cause of the inflammatory reaction within the arterial wall that causes obstruction.