1/438. Hypotensive response to captopril: a potential pitfall of scintigraphic assessment for renal artery stenosis.A characteristic pattern seen on captopril renography is described that is due to systemic hypotensive response. Most patients with these findings on captopril renography do not receive renal artery angiograms in our clinic because it is usually recognized. However, this pattern has received little attention in the medical literature and may be misinterpreted as being due to physiologically significant renal artery hypertension. methods: Over the last 3 y, renal artery angiograms were performed on three patients with systemic hypotensive response pattern on captopril renography. This allowed a unique opportunity to correlate the results of the captopril renogram with the renal artery angiograms in this patient population. captopril renography was performed with a glomerular filtration agent, diethylenetriamine pentaacetic acid (DTPA), and a tubular agent, o-iodohipurate (OIH). RESULTS: renal artery angiograms showed no evidence of renal artery stenosis in three patients with systemic hypotensive response pattern on captopril renography. Systemic hypotension on captopril renograms results in preserved uptake of both DTPA and OIH and hyperconcentration in the cortex and collecting system. CONCLUSION: The systemic hypotensive response pattern seen on captopril renography is a distinctive pattern that does not represent physiologically significant renal artery stenosis.- - - - - - - - - - ranking = 1keywords = stenosis (Clic here for more details about this article) |
2/438. University of Miami Division of Clinical pharmacology Therapeutic Rounds: ischemic renal disease.Ischemic renal disease (IRD) is defined as a significant reduction in glomerular filtration rate and/or loss of renal parenchyma caused by hemodynamically significant renal artery stenosis. IRD is a common and often overlooked clinical entity that presents in the setting of extrarenal arteriosclerotic vascular disease in older individuals with azotemia. IRD is an important cause of chronic renal failure and end-stage renal disease (ESRD), and many patients with a presumed diagnosis of hypertensive nephrosclerosis may actually have undiagnosed ischemic nephropathy as the cause of their ESRD. The primary reason for establishing the diagnosis of IRD is the hope that correction of a renal artery stenosis will lead to improvement of renal function or a delay in progression to ESRD. There are six typical clinical settings in which the clinician could suspect IRD: acute renal failure caused by the treatment of hypertension, especially with angiotensin-converting enzyme inhibitors; progressive azotemia in a patient with known renovascular hypertension; acute pulmonary edema superimposed on poorly controlled hypertension and renal failure; progressive azotemia in an elderly patient with refractory or severe hypertension; progressive azotemia in an elderly patient with evidence of atherosclerotic disease; and unexplained progressive azotemia in an elderly patient. It is important for the clinician to identify IRD, because IRD represents a potentially reversible cause of chronic renal failure in a hypertensive patient.- - - - - - - - - - ranking = 0.33333333333333keywords = stenosis (Clic here for more details about this article) |
3/438. Noninvasive assessment of renal artery stenosis by combined conventional and color Doppler ultrasound.We describe four angiographically-proven patients in whom Doppler color flow imaging in conjunction with conventional Doppler correctly diagnosed significant renal artery stenosis in three and ruled out stenosis in the fourth case.- - - - - - - - - - ranking = 1keywords = stenosis (Clic here for more details about this article) |
4/438. Radionuclide renography: a personal approach.Recent advances have increased the value of radionuclide renography in evaluating the patient with suspected disease of the genitourinary tract. The use of the consensus process to help standardize procedures and recommend interpretative criteria provides guidance for the nuclear medicine practitioner, serves as a basis to improve the standard of practice, and facilitates pooling of data from different centers. This review draws on the consensus criteria to present a personal approach to radionuclide renography with a particular emphasis on diuresis renography and the detection of renovascular hypertension. patients are encouraged to come well hydrated and void immediately prior to the study. Our standard radiopharmaceutical is 99mTc mercaptoacetyltriglycine (MAG3). Routine quantitative indices include a MAG3 clearance, whole kidney and cortical (parenchymal) regions of interest, measurements of relative uptake, time to peak height (Tmax), 20 min/max count ratio, residual urine volume and a T(1/2) in patients undergoing diuresis renography. A 1-minute image of the injection site is obtained at the conclusion of the study to check for infiltration because infiltration can invalidate a plasma sample clearance and alter the renogram curve. A postvoid image of the kidneys and bladder is obtained to calculate residual urine volume and to better evaluate drainage from the collecting system. In patients undergoing diuresis renography, the T(1/2) is calculated using a region of interest around the activity in the dilated collecting system. A prolonged T(1/2), however, should never be the sole criterion for diagnosing the presence of obstruction; the T(1/2) must be interpreted in the context of the sequential images, total and individual kidney function, other quantitative indices and available diagnostic studies. The goal of ACE inhibitor renography is to detect renovascular hypertension, not renal artery stenosis. patients with a positive study have a high probability of cure or amelioration of the hypertension following revascularization. In patients with azotemia or in patients with a small, poorly functioning kidney, the test result is often indeterminate (intermediate probability) with an abnormal baseline study that does not change following ACE inhibition. In patients with normal renal function, the test is highly accurate. To avoid unrealistic expectations on the part of the referring physician, it is often helpful to explain the likely differences in test results in these two-patient populations prior to the study.- - - - - - - - - - ranking = 0.16666666666667keywords = stenosis (Clic here for more details about this article) |
5/438. The diagnosis of segmental transplant renal artery stenosis by captopril renography.The captopril renogram test has been shown to be a sensitive test for the diagnosis of renal artery stenosis in native and transplanted kidneys. Most reports have involved only stenosis of the main renal artery. Although segmental renal artery stenosis has been diagnosed successfully in native kidneys, it is not clear whether the captopril renogram test can diagnose segmental renal artery stenosis in a transplanted kidney. The authors report two cases of successful identification, by the captopril renogram test, of functionally significant stenosis in an intrarenal branch of a single transplant renal artery.- - - - - - - - - - ranking = 1.5keywords = stenosis (Clic here for more details about this article) |
6/438. Successful Wallstent implantation for extensive iatrogenic renal artery dissection in a patient with fibromuscular dysplasia.PURPOSE: To describe a case of renal artery stenosis with fibromuscular dysplasia (FMD) and extensive iatrogenic dissection treated with Wallstent implantation. methods AND RESULTS: An 83-year-old woman with a history of coronary artery disease and hypertension presented at another facility with exertional angina and poorly controlled hypertension. Renal arteriography uncovered a critical right renal artery stenosis with severe FMD. However, angioplasty resulted in extensive dissection of the renal artery, for which the patient was referred to our institution. The renal artery was recanalized via the left brachial approach with restoration of flow using a Wallstent and a Palmaz stent. The patient's blood pressure was controllable after this procedure, and follow-up duplex imaging with flow velocities at 6 months showed patent right renal artery stents. CONCLUSIONS: Owing to its length and flexibility, the Wallstent endoprosthesis was a useful treatment modality in this case of extensive renal artery dissection.- - - - - - - - - - ranking = 0.33333333333333keywords = stenosis (Clic here for more details about this article) |
7/438. A case of renal artery stenosis secondary to chronic pancreatitis.We report a case of renal artery stenosis most probably secondary to chronic pancreatitis. The patient had a traumatic pancreatic fistula. This was followed by numerous attacks of pancreatitis in the following years. At a relatively young age, he developed hypertension. Examinations revealed a right renal artery stenosis which was successfully treated by a percutaneous angioplasty. This rare complication should be kept in mind as a possible complication of pancreatitis.- - - - - - - - - - ranking = 1keywords = stenosis (Clic here for more details about this article) |
8/438. Percutaneous transluminal angioplasty of renal artery stenosis in a child with hypertensive heart disease.A 1.5-year-old girl developed congestive heart failure 9 months after she presented with hypertension. The hypertension was caused by a renal artery stenosis. A short-segment stenosis at the ostium of the left renal artery was confirmed by arteriogram. After balloon angioplasty, the blood pressure and heart function returned to normal. angioplasty had an excellent result of relieving hypertension and heart failure in this patient. Cathet. Cardiovasc. Intervent. 48:374-377, 1999.- - - - - - - - - - ranking = 1keywords = stenosis (Clic here for more details about this article) |
9/438. renal artery stenosis associated with epidermal nevus syndrome.Epidermal nevus syndrome is an unusual neurocutaneous disorder in which epidermal nevi are associated with abnormalities of the skeleton and central nervous system, including the eyes and somtimes the cardiovascular system. We treated a patient in whom the latter included renal artery stenosis. An 18-year-old man with epidermal nevi was diagnosed as having the syndrome based on the additional presence of scoliosis, an arachnoid cyst in the middle cranial fossa, and microphthalmos. hypertension was diagnosed when the patient was 15 years old. The plasma renin activity (9.7 ng/ml/h) was elevated. Right renal artery stenosis was demonstrated by angiography, and the abdominal aorta was narrowed distal to the ostium of the superior mesenteric artery. The plasma renin activity in the right renal vein (16 ng/ml/h) was higher than contralaterally (10 ng/ml/h). Several cardiovascular manifestations have been reported as a complication of epidermal nevus syndrome. hypertension in an individual with epidermal nevi and congenital anomalies should prompt a search for a vascular anomaly.- - - - - - - - - - ranking = 1keywords = stenosis (Clic here for more details about this article) |
10/438. enalapril and losartan augment endogenous nitric oxide release in Takayasu's arteritis--a case report.prognosis in Takayasu's arteritis is limited owing to renovascular hypertension. The authors report a patient with Takayasu's arteritis who had been unilaterally nephrectomized and presented with malignant hypertension due to renal artery stenosis. hypertension was refractory to conventional antihypertensive treatment, and stenosis was not accessible by interventional angioplasty. Initiation of enalapril and losartan therapy was successful in improving blood pressure without deterioration of renal function due to ischemic failure. Antihypertensive treatment resulted in dramatically stimulated endogenous nitric oxide (NO) synthesis, while elevated plasma endothelin-1 levels were unchanged. Renovascular hypertension in Takayasu's arteritis is associated with an imbalance of vasoconstrictor peptide endothelin-1 and vasodilator peptide NO. Successful treatment of hypertension by enalapril or losartan results in improved endogenous NO synthesis, which putatively counterbalances excessive vasoconstrictor actions and may retard the progression of renal failure.- - - - - - - - - - ranking = 0.33333333333333keywords = stenosis (Clic here for more details about this article) |
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