Cases Of Renal Artery Stenosis Research Articles

Renal artery stenosis: when to intervene?

Indications and timing of revascularization for atherosclerotic renal artery stenosis are topics of considerable controversy. Labile hypertension, progressive renal failure, and flash pulmonary edema may be strong indications for revascularization, yet revascularization may carry significant morbidity and mortality risks. Medical therapy alone, however, may also risk deterioration of renal function with worsening morbidity and mortality. We report a case of renal artery stenosis illustrating some of the complexities of decision-making, the limitations of angiography, and the importance of physiologic testing.

Renovascular Hypertension due to Takayasu's Arteritis Demonstrated by Tc-99m Ethylenedicysteine Captopril Scintigraphy

A 34-year-old woman with severe hypertension underwent Tc-99m ethylenedicycteine (Tc-99m EC) captopril renal scintigraphy. There was bilateral parenchymal retention of the tracer suggesting renal artery stenosis. Angiography confirmed bilateral renal artery stenosis and also demonstrated contour irregularities of the abdominal aorta, and stenosis in mesenteric and subclavian arteries with increased collateral circulation consistent with Takayasu's arteritis. In light of this case of renal artery stenosis, it was concluded that Tc-99m EC can be used successfully as a potential renal agent in the diagnosis of renal involvement in patients with Takayasu's arteritis.

Technetium-99m-Ethylenedicysteine in the Diagnosis and Follow-Up of Renovascular Hypertension

Technetium-99m-ethylenedicysteine (99mTc-EC) captopril scintigraphy performed in a patient with severe hypertension revealed increased parenchymal retention in the left kidney, suggesting renal artery stenosis. After angiographic confirmation of renal artery stenosis, percutaneous transluminal angioplasty (PTA) was performed on the left renal artery. Captopril scintigraphy after PTA showed normal findings with no evidence of parenchymal retention, consistent with reversal to normal kidney functions. In light of this case of renal artery stenosis, it was concluded that 99mTc-EC can be used successfully as a potential renal agent in the diagnosis and follow-up of renovascular hypertension.

CLINICAL STUDY OF SURGICAL COMPLICATIONS AFTER RENAL TRANSPLANTATION

During a period from July 1982 to April 1995, 71 cases of renal transplantation from 34 living related and 37 cadaveric donors were performed in this institute. We studied 18 cases (25.4%) in which surgical complications were found. From July 1982 through November 1992, the ureter was inserted into the bladder with a Paquin technique, and an Alexandre technique was performed after December 1992. The risk factors of surgical complications were not associated with age, donor, operation time and duration of pre-operative hemodialysis, but these complications were predominantly seen in males. On wound complications there were 5 cases of wound bleeding, 2 cases of abscess, 6 cases of lymphocele, 2 cases of hydrocele testis and one case of incisional hernia. There were 3 cases of ureteric stricture, one case of urinary leakage and 3 cases of vesical bleeding on urinary complications and one case of renal artery stenosis and one case of graft rupture. No urinary complications occurred after we employed an Alexandre technique. Surgical complications were not associated with the rejection, and the graft and patient survival. Meticulous operative technique may be the crucial factor associated with a minimal incidence of surgical complications after renal transplantation.

Two Cases of Renal Artery Stenosis Caused by Takayasu's Arteritis : Treatment with the Palmaz-Schatz Biliary Stent

Two Cases of Renal Artery Stenosis Caused by Takayasu's Arteritis : Treatment with the Palmaz-Schatz Biliary Stent

The renin-secreting cell and the glomerular peripolar cell in renal artery stenosis and Addison's disease.

The glomerular peripolar cell may be a secretory component of the juxtaglomerular apparatus. To investigate this hypothesis we studied kidneys with the renin-angiotensin system activated by two different stimuli in order to compare the responses of peripolar cells and renin-secreting cells. We examined 10 human kidneys, removed for renal artery stenosis and 11 autopsy cases of Addison's disease with appropriate controls. We counted granulated peripolar cells in serial paraffin-embedded sections and renin-containing cells were quantified using an immunoperoxidase technique with an antiserum to human renin. There was a five-fold increase in the number of renin-containing cells in both renal artery stenosis and in untreated, but not in treated, Addison's disease. Peripolar cells were increased in number in three cases of renal artery stenosis, but were unaltered in both treated and untreated Addison's disease. Therefore, neither a reduction in renal perfusion pressure (renal artery stenosis), nor sodium depletion (Addison's disease) consistently affect peripolar cells in humans. These findings do not support the hypothesis that the peripolar cell is part of the juxtaglomerular apparatus.

Surgical Treatment of Complete Renal Artery Occlusion in Pediatric Patients

Two children, 8 and 11 years old, presented with severe hypertension secondary to unilateral and bilateral total occlusion of the renal arteries, respectively. The 11-year-old developed sudden anuria requiring hemodialysis. Successful surgical reconstruction allowed recovery of renal function and normal blood pressure in both patients. Routine blood pressure control in the pediatric patient population, high clinical awareness, and judicious use of arteriography, provide the best chance for early diagnosis of renovascular disease. Surgical revascularization or transluminal angioplasty are the treatment modalities of choice in appropriately selected cases of renal artery stenosis. When total occlusion occurs, retrieval or preservation of renal function can be successfully achieved by direct surgical intervention.

Duplex Doppler ultrasound in determination of renal artery stenosis.

Twenty-six cases of renal artery stenosis were evaluated with Doppler ultrasound using the pulsatile flow index (PFI). To establish normal values, the PFI in 60 renal arteries in 30 healthy volunteers was obtained. Normal values by PFI ranged between 0.48 and 0.71 (mean +/- SD: 0.6 +/- 0.06). In renal artery stenosis the PFI range was 0.72-0.79. The normal upper limit was 0.71. The PFI failed in three patients; however, an ultrasound examination showed secondary renal disease (two patients with stenosis on both sides with a shrunken kidney on one side, and one patient with hypernephroma on the opposite side). The PFI was normal (14 of 14 patients) in patients without angiographic evidence of stenosis or after successful dilatation.

Noncoronary angioplasty.

PTA is an established method of revascularization in a variety of medical conditions. It is performed for specific morphologic and clinical indications. PTA is the procedure of choice in Fontaine stage IIB through IV lower extremity ischemia due to iliac and/or femoropopliteal stenosis or short occlusion. Its role is less certain in infrapopliteal disease, although current studies have begun to establish long-term effectiveness. PTA is the procedure of choice for renal revascularization in renovascular hypertension due to fibromuscular disease or non-ostial atherosclerosis, selected cases of renal artery stenosis associated with renal insufficiency, and transplant renal artery stenosis. It is also useful in treating the renovascular component of complex hypertension and may be indicated in severe renal artery stenosis (75%-99%), even in the absence of clinically demonstrable RVHTN. PTA has limited applications in the venous system and only short-term success in the treatment of stenoses in dialysis access fistulas. PTA often serves as an important adjunct to surgical revascularization by providing improved inflow or outflow. PTA is the procedure of choice when anatomically feasible in subclavian steal syndrome. The role of PTA in carotid artery disease, particularly atheromatous disease of the internal carotid artery, is uncertain. The same may be said of PTA for vertebral artery stenosis, although the overwhelming majority of vertebral artery stenoses are morphologically suitable for PTA. PTA and surgery are both effective in the treatment of abdominal angina. There are more data available to verify the long-term patency of thromboendarterectomy and bypass grafts than PTA for mesenteric ischemia. However, since the technical success for PTA is high and since coronary co-morbidity is the most common cause of perioperative mortality in surgical series, PTA should be seriously considered as the procedure of first choice. Serious complications of PTA occur in approximately 5% of cases. Two to three percent of PTA patients have complications requiring surgery or causing a prolongation or alteration of hospital course. The morbidity, mortality, and cost associated with PTA are low. The discomfort is minor, and postprocedural recovery rapid. The major limitations of PTA include its unsuitability for some lesions (long-segment occlusions and stenoses, orifice lesions, eccentric lesions) and postangioplasty restenosis. These problems are being addressed by ongoing laboratory and clinical research. In the near future, it is likely that endoluminal transmural sonography of the vessel wall will help guide our interventions.

Histological and ultrastructural studies of the human juxtaglomerular apparatus in Bartter's syndrome and renal artery stenosis.

Histological and ultrastructural studies of the juxtaglomerular apparatus (JGA) were performed on renal biopsy material from three cases of Bartter's syndrome and two cases of renal artery stenosis. These cases of known JGA hyperfunction were compared with the apparatus in a presumed inactive or basal state as in minimal lesion glomerulonephritis. Light microscopic assessment of the ease of JGA identification, its size and cellularity, provides a valuable reflection of activity and indicates those cases which require ultrastructural assessment of granule turnover. Granule stains often failed to demonstrate any significant increase in granule number in the two conditions studied, and only ultrastructural studies allowed evaluation of secretory activity, rhomboid granule formation and granule release. From these investigations, a proposed mechanism of granule turnover is suggested. The morphological findings in both Bartter's syndrome and renal artery stenosis support the concept of hyperfunction of the apparatus. They may help to elucidate the pathogenesis of Bartter's syndrome and to predict the outcome of surgical intervention in renal artery stenosis. Such studies could profitably be performed on renal biopsies in other disease states, so augmenting our understanding of the contribution of the JGA to the pathogenesis of a variety of glomerular and vascular lesions.

Renal perfusion-excretion determination as “split-function study” in diagnosis of segmental renal artery stenosis in a child

A case of renal artery stenosis (RAS) is described in a seven-year-old boy. The pre-operative renal perfusion-excretion determination (RPED) was diagnostic of renal artery stenosis. In addition, after corrective surgery the postoperative RPED showed relatively normal values with a decrease in tubular transport time (TTT), an anticipated finding in patients with corrected RAS. This patient also represents an interesting example of intrarenal collateral vessel formation in an ischemic kidney.

Radiation-induced renovascular hypertension

Radiation is known to produce changes in the small vessels and interstitium of the kidneys resulting in hypertension. Two cases of renal artery stenosis and resultant hypertension secondary to abdominal irradiation are reported and the literature is reviewed.

Management of hypertension of renal origin

Studies as clinically warranted were accomplished in more than 2,000 patients seen from January 1964 through December 1968 because of hypertension and suspected or proved renal disease. Data from the clinical history, physical examination, laboratory investigation and results of surgical or medical treatment are reported for 100 cases each of 5 entities—glomerulonephritis, pyelonephritis, renal cyst, renal tumor and apparent primary hypertension with renal disease. Comparison is made with data included from 100 cases of renal artery stenosis and hypertension. Female patients numbered 286, and predominated in the groups with renal artery stenosis and with pyelonephritis. Ages ranged from 6 to 81 years. Hypertension was less severe in the groups with renal tumor or cyst. Hypertensive changes of the retinal arterioles were more severe in the group with renal artery stenosis and in the group with primary hypertension, and renal function was more severely impaired with glomerulonephritis and primary hypertension. Surgical treatment was given 234 patients, 71 of whom later had normal blood pressures without medical treatment. For 366 patients medical treatment was primary; 125 of these usually maintained diastolic blood pressure of less than 90 mm Hg. Sodium restriction proved a valuable part of conservative management in most cases. Dialysis or transplantation, or both, were required for 49 patients. In the 600 cases, 507 patients are alive 2 to 13 years after initial examination, and 93 have died.

An 8-year-old boy with renal artery stenosis and cerebral infarct

Secondary hypertension is more common in children compared to that in adults, leading to organ damage and increased mortality. Renal artery stenosis could be a sequel to secondary hypertension in children and give rise to serious outcomes. A case of renal artery stenosis in an eight year old boy is presented in this study in whom PTA was performed with successful results. Blood pressure was controlled and all antihypertensive drugs could be withdrawn in a short period of time.Ibrahim Med. Coll. J. 2011; 5(1): 32-33 Indexing words: Secondary hypertension; children; renal artery stenosis; surgery.DOI: http://dx.doi.org/10.3329/imcj.v5i1.9862

Factors affecting the aortographic evaluation of differential renal blood flow.

The actual mechanism which produces renovascular hypertension is not known. The most popular hypothesis is the renin-angiotensin theory whereby the affected kidney releases excessive renin which results in an increased amount of the active hypertensive agent, angiotensin, in the blood stream. The juxtaglomerular cells of the kidney are supposedly the source of the renin, but there is some question as to the stimulus acting on these cells. Some investigators state that diminished blood pressure in the kidney is responsible; others point to a diminished pulse pressure as the inciting agent. In favor of the diminished head-of-pressure theory (and consequently diminished renal blood flow) is the fact that in only those cases of renal artery stenosis in which there is a sizable blood pressure gradient (e.g., greater than 40 mm Hg) does corrective surgery lower the systemic blood pressure (10). Hence, an easily available clinical procedure which could determine differential renal blood flow in the two kidneys w...

Renin and arterial hypertension

SummaryPlasma renin activity has been measured with Boucher’s technique. In normal adults, the mean value of renin activity is 29,2 nanogrammes of angiotensin liberated/10 ml of plasma (S.D. ± 6,5). In 81 cases of essential hypertension, renin activity averaged 17,4 ng/10 ml (S.D. ± 4,5). In 16 cases of renal artery stenosis, renin activity averaged 80,2 ng/10 ml (S.D. + 44).However, in 5 of these cases, renin activity was only at the upper limit of the normal ranges. Normal renin plasma activity in causative renal artery stenosis can be explained in three ways :1) Systemic plasma renin activity does not reflect renal secretion in tight stenosis with low renal plasma flow; in 4 cases of renal artery stenosis with paranormal renin activity in systemic blood, renin activity in venous blood was high (304 ng/10 ml); stenotic renal artery blood flow averaged in these cases 45 ml/ minute.2) Renal blood flow and renin plasma activity may be normal in the reclining subjects and abnormally increased in erect posit...

PHEOCHROMOCYTOMA AND RENAL ARTERY STENOSIS. SURGICAL TREATMENT OF SECONDARY HYPERTENSION: A CASE REPORT.

ARTERIAL hypertension due to pheochromocytoma is dramatically relieved in most patients by complete excision of the tumor. Harrison and associates1have reported a patient in whom renal ischemia developed or persisted after excision of three pheochromocytomas requiring nephrectomy for relief of hypertension. Renal ischemia secondary to renal artery stenosis is a well-recognized cause of hypertension2and can be cured by operation3,4in the majority of patients. Renal artery stenosis and pheochromocytoma occurring simultaneously have been reported by Rosenheim et al.5Two patients with unilateral renal ischemia due to compression of the renal artery by pheochromocytomas were treated by excision of the tumor and nephrectomy. The purpose of this report is to present the first documented case of renal artery stenosis and pheochromocytoma successfully treated by operation with salvage of the kidney and to discuss the possible relationship between the two lesions. Report of Case A 38-year-old

Renal artery stenosis

Summary Forty-six cases of renal artery stenosis have been diagnosed by arteriography at St Mary's Hospital. Twenty cases were observed as coincidental findings in some 1,000 patients being examined for aortoiliac vascular disease. Twenty-six cases were discovered among 260 unselected hypertensive patients investigated by aortography. The plain radiographic, pyelographic, and arteriographic findings in these patients are analysed and reviewed, and the effect of “water load” on the pyelogram is described. Renal artery stenosis can be diagnosed or strongly suspected on a combination of plain radiological and pyelographic changes consisting of a relatively small kidney with small “spastic” calyces and relatively better contrast excretion. Many factors are involved, however, and this radiological complex is only present in a minority of cases. The clinical aspects of renal artery stenosis are discussed. The relationship to hypertension and the laboratory and histological findings are reviewed, with special reference to “functional” renal artery stenosis.