Successful Renal Angioplasty Research Articles

Clinical characteristics of concurrent primary aldosteronism and renal artery stenosis: A retrospective case–control study

ABSTRACT Background: Rare cases of concurrent primary aldosteronism (PA) and renal artery stenosis (RAS) have been reported. Methods: In this retrospective case–control study, we selected a cohort of 10 PA with RAS patients and a control group of 20 PA without RAS patients from January 1, 2006, to January 1, 2016. Results: All patients presented with refractory hypertension, and a nonstatistically significant trend toward lower mean serum potassium was seen in the PA with RAS group (p =.07). PA with RAS patients had lower mean orthostatic aldosterone-to-renin ratios (38.4 ± 41.4 ng dL−1/ng mL−1 h−1 vs. 87.4.4 ± 38.4 ng dL−1/ng mL−1 h−1, respectively; p < .01) and a higher false-negative rate (50% vs. 15%, respectively; p < .05) compared with controls. All misdiagnosed patients had the diagnosis of PA confirmed when we revaluated the repeated screening and confirmative tests because of residual hypertension or hypokalemia after successful revascularization of renal artery stenosis. Conclusions: PA is easily missed in patients with RAS because of the high false-negative rate for screening tests. RAS patients with residual hypertension after successful renal angioplasty should be monitored for coexisting PA. Reevaluation of screening and confirmatory tests is helpful in establishing the correct diagnoses.

Complex renal angioplasty in a solitary functioning kidney due to fibromuscular dysplasia

33-year-old female with refractory hypertension was found to have severe bilateral renal artery stenosis caused by perimedial fibromuscular dysplasia. Angiography showed near total occlusion of right renal artery with shrunken kidney and complex bifurcation disease of left renal artery. She underwent successful renal angioplasty and stenting of left renal artery following which blood pressure normalized.

Reduced spontaneous baroreceptor sensitivity in patients with renovascular hypertension

Sympathetic nerve activity is increased in hypertensive patients with renal artery stenosis. Less is known about cardiac vagal function in these patients before and after renal angioplasty. The aim of the present study was to investigate cardiac baroreceptor reflex sensitivity together with total body noradrenaline (NA) spillover in hypertensive patients with renal artery stenosis before, and in some patients, 1 year after renal angioplasty. Spontaneous baroreceptor reflex sensitivity and total body noradrenaline (NA) spillover were measured in patients with renovascular hypertension before intervention (n = 18), patients being cured/improved 1 year after renal angioplasty (n = 5) and age-matched healthy subjects (n = 25). Hypertensive patients with renal artery stenosis had higher total body NA spillover (4630 +/- 619 versus 3132 +/- 210 pmol/min, P < 0.05) and reduced cardiac baroreceptor reflex sensitivity (6.1 +/- 1.0 versus 10.7 +/- 1.0 ms/mmHg, P < 0.01) compared with healthy subjects. Similar results were obtained (before intervention) in a subgroup of patients (n = 9) with renovascular hypertension defined as cured/improved 1 year following renal angioplasty. Baroreceptor reflex sensitivity improved after renal angioplasty in a subset of patients showing good blood pressure control 1 year after intervention (6.4 +/- 0.7 to 9.4 +/- 1.7 ms/mmHg, P < 0.05). Patients with renovascular hypertension showed reduced cardiac baroreceptor reflex sensitivity and increased noradrenergic activity, which to some extent was reversed 1 year following successful renal angioplasty.

Percutaneous transluminal angioplasty for stenosis of the aorta due to aortic arteritis in children.

Percutaneous transluminal balloon angioplasty for stenosis of the aorta due to aortic arteritis was attempted on 45 lesions in 41 children (age range, 4-14 years; mean, 9.9+/-4.2 years) presenting with symptoms of hypertension, severe congestive heart failure, and lower limb claudication. Balloon dilatation was technically successful in 38 (92.7%) patients for 41 stenotic lesions (91.1%). The mean peak systolic pressure gradient (PSG) decreased from 71.7 +/- 23.9 mmHg to 23.2 +/- 17.5 mmHg (p < 0.001) and the diameter of the stenosed segment increased from 3.3 +/- 1.1 mm to 7.5 +/- 2.2 mm (p < 0.001) immediately after angioplasty. Patients with short-segment (<3 cm) stenosis had a lower residual gradient (17.9 +/- 11.1 mmHg vs 30.5 +/- 22.6 mmHg; p < 0.05) and a wider diameter of the aorta (8.8 +/- 1.1 mm vs 7.5 +/- 2.2 mm; p < 0.02) compared to patients with long-segment (>/=3 cm) stenosis. Four patients required stent implantation; 2 for flow-limiting dissection, 1 for failure to reduce PSG by >50%, and 1 for recurrent restenosis. There was marked hemodynamic and angiographic improvement in these 4 patients. Hemodynamic and angiographic restudy in 21 of the 41 patients at mean follow-up period of 6.2 +/- 4.2 months (range, 3-24 months) showed restenosis in 4 (19%) patients. Restenosis was more common in patients with long-segment stenosis than those with short-segment stenosis (30% vs 9.1%). Late restudy in 8 patients, done at 3-7 years after first restudy, showed no recurrence of aortic narrowing. On clinical follow-up of 38 patients for a mean of 58.8 +/- 36.0 months (range, 8-146 months) there was marked improvement in symptoms. Hypertension was cured in 11 (29%), improved in 24 (63%), and persisted in 3 (8%). Six patients with associated severe renal artery stenosis showed further improvement in hypertension after successful renal angioplasty. Severe congestive heart failure improved in 21 (95.4%) of 22 patients. Mean left ventricular ejection fraction improved from 0.32 +/- 0.08 to 0. 48 +/- 0.10 (p < 0.001) at a mean follow-up of 28.7 +/- 8.4 months in these patients. Hemodynamic restudy in 10 of these patients showed improvements in left ventricular end-diastolic pressure from a mean 37 +/- 9 mmHg (range, 25-55 mmHg) to 16.4 +/- 6.2 mmHg (range, 6-25 mmHg) (p < 0.001). Lower limb claudication improved in all 4 patients. Our results suggest that percutaneous transluminal balloon angioplasty in children is safe and highly effective in relieving stenosis of the aorta due to aortic arteritis, with marked clinical improvement, and should be the treatment of choice particularly for discrete stenosis.

Endothelin-1 urinary excretion, but not endothelin-1 plasma concentration, is increased in renovascular hypertension

Animal experiments have shown an increase in prepro-endothelin-1 (prepro-ET-1) mRNA expression in the clipped kidney but none in the aortic and mesenteric arteries in 2-kidney, 1-clip Goldblatt hypertensive rats. The present study was aimed at investigating whether plasma and renal endothelin-1 (ET-1) systems are differently activated in patients with renovascular hypertension (RH). The plasma concentration and urinary excretion of ET-1 were measured in 5 patients with RH (before and after successful renal angioplasty), in 7 patients with essential hypertension (EH), and in 8 normotensive control subjects. Immediately before renal angioplasty, plasma samples for ET-1 and plasma renin activity (PRA) measurements were withdrawn from the aorta and both renal veins. Unlike the PRA, the plasma ET-1 concentration did not significantly differ between the involved and the uninvolved sides. The urinary ET-1 excretion level (Fig 1) was markedly increased in patients with RH (30 ± 4 ng/g urinary creatinine (UC) vs 2.5 ± 0.2 ng/g UC and 2.6 ± 0.5 ng/g UC in control subjects and patients with EH, respectively; P < .001), whereas the plasma ET-1 concentration was normal (0.8 ± 0.2 pg/mL vs 0.65 ± 0.3 pg/mL and 0.8 ± 0.2 pg/mL in control subjects and EH, respectively, not significant). Renal angioplasty was followed in all patients by normalization of blood pressure and PRA. One week after angioplasty, urinary ET-1 decreased to one fourth of baseline (8.04 ± 5.23 ng/g UC, P < .001 vs values before angioplasty and P < .04 vs control subjects) and normalized 1 month thereafter (3.13 ± 1.62 ng/g UC, not significant vs control subjects), whereas plasma ET-1 remained steady. The present findings clearly indicate that in patients with RH, urinary ET-1 excretion is increased, whereas plasma ET-1 concentration remains normal. Successful percutaneous transluminal renal angioplasty induced a notable reduction in ET-1 urinary excretion, whereas it did not affect ET-1 plasma concentration.

Restenosis after a first percutaneous transluminal renal angioplasty.

The incidence of restenosis after a first successful percutaneous transluminal angioplasty of a native renal artery and the clinical and angiographic variables that may influence its occurrence were studied in 104 hypertensive patients. Angiograms obtained immediately before and after angioplasty and, in 92 patients, 8.8 +/- 6.0 months after angioplasty were interpreted separately by two observers. Stenosis severity was classified into five grades, and restenosis was defined by a stenosis one grade or more higher at follow-up than immediately after angioplasty. Interobserver concordance for etiology, stenosis grade, and other angiographic items yielded kappa coefficients in the range of 0.328-0.942. Sessions were organized to reach a consensus in each case. Ostial stenoses were more frequent in patients with atheromatous stenoses, and branch stenoses were more frequent in those with fibromuscular dysplasia. There was no significant difference between the 15 patients (16%) with restenosis and those without concerning sex distribution, mean age, mean blood pressure, plasma creatinine level, and etiology distribution. Truncal stenoses were less prone to restenosis than ostial or branch stenoses (12% versus 35%, respectively; 95% confidence interval of difference, -0.6% to 47%). In patients with atheromatous stenoses, aortitis or aortic ectasia were associated with a high restenosis incidence (35% when present versus 8% when absent; 95% confidence interval of difference, 5% to 48%). In conclusion, restenosis was observed in one sixth of patients after a first successful renal angioplasty; its incidence was low in patients with truncal stenoses and high in those with severe aortic atheroma. Automated renal artery stenosis quantification methods are needed to standardize stenosis description.

Single-Dose Captopril Scintigraphy in the Diagnosis of Renovascular Hypertension

Renal scintigraphy with [99mTc]diethylenetriaminepentaacetic acid (DTPA) and/or sodium-iodine-131-o-iodohippurate (HIP) was performed before and after an oral dose of captopril (50 mg) in 18 patients with renovascular hypertension (RVH) due to renal artery stenosis (RAS) and 18 controls. In every patient with RVH, captopril induced, enhanced or sustained abnormal findings on HIP scintigraphy depending on the degree of RAS. With DTPA scintigraphy, renal function decreased after captopril in ten kidneys with RVH-related RAS and adequate baseline renal function, but this phenomenon was not evident in 11 kidneys with RVH and poor renal function. Captopril did not influence HIP or DTPA studies of kidneys with patent renal arteries (patients after successful renal angioplasty, patients with essential hypertension, contralateral kidneys of patients with unilateral RVH) or ipsilateral kidneys with mild and subcritical (less than 60%) RAS in patients without hypertension and/or normal renal vein renin activity. When HIP and DTPA scintigraphy were compared in the same patients, HIP demonstrated greater sensitivity and specificity than DTPA, particularly in patients with poor renal function. HIP scintigraphy before and after a single dose of captopril may provide a rapid sensitive and minimally invasive test for screening patients with hypertension.

Predictive Value and Changes of Renin Secretion in Hypertensive Patients With Unilateral Renovascular Disease Undergoing Successful Renal Angioplasty

Predictive Value and Changes of Renin Secretion in Hypertensive Patients With Unilateral Renovascular Disease Undergoing Successful Renal Angioplasty

Predictive value and changes of renin secretion in hypertensive patients with unilateral renovascular disease undergoing successful renal angioplasty

Peripheral and renal vein renin activity was measured in 46 hypertensive patients with arteriographically diagnosed unilateral renal artery stenosis before and six months after technically successful renal angioplasty. The renin-sodium profile was high in 80 percent before angioplasty, fell in all patients, and became normal or low in 85 percent after angioplasty. Renal vein renin activity, which initially showed lateralization of renin secretion to the ischemic kidney with contralateral suppression, became normal. Renal vein renin activity was more reliable for predicting the therapeutic response when expressed as the increment of renin for each renal vein over the infrarenal vena caval value (sensitivity 74 percent, specificity 100 percent) than as the ratio between the two renal veins (sensitivity 62 percent, specificity 60 percent). The predictive value of renal vein renin activity is poor when plasma renin activity is stimulated by long-term administration of captopril. These data support the usefulness and define the limitations of peripheral and renal vein renin measurements in selecting patients for treatment by renal angioplasty.

Percutaneous transluminal angioplasty of the renal arteries: intravenous digital subtraction angiography for follow-up.

A group of 50 consecutive patients who had undergone successful renal angioplasty two or more years previously was studied by video digital subtraction angiography (DSA). Thirty additional patients were studied by both DSA and conventional catheter arteriography. Among the 30 patients, DSA findings agreed with the arteriographic findings in 87% of the examinations: 92% of the postangioplasty patients had satisfactory DSA examinations. Using DSA two years after angioplasty, we were able to determine a restenosis rate of 22.5% among patients with atherosclerosis and of 0% among patients who had fibromuscular disease. DSA provides a useful method to follow-up renal angioplasty, and it is well accepted by patients.