Renovascular hypertension in elderly patients.

In elderly patients with uncontrolled hypertension or increasing azotemia caused by renovascular disease, hepatorenal or splenorenal bypass procedures are helpful alternatives. The presence of diffuse atherosclerosis makes aortorenal bypass technically difficult. Surgery of this type can be accomplished with acceptable morbidity and mortality, even in suitably screened elderly patients.     

Case 6: Renovascular hypertension

Renovascular hypertension is a progressive disorder that can result in serious complications without adequate treatment. Unfortunately, identification of patients with the condition is often difficult, and the optimal approach to management continues to be debated.     

Renovascular hypertension: an update

Renovascular hypertension, the most common remediable cause of elevated blood pressure, is a controversial topic, but most authorities agree on several principles. The absolute risk of renovascular hypertension for a specific patient can be estimated using only clinical information, thereby sparing many patients further expensive and potentially dangerous evaluations. Patients with a high absolute risk of renovascular hypertension should have angiography only if they are willing to undergo revascularization if warranted. A screening test (captopril renography, Doppler ultrasonography, magnetic resonance angiography, or computed tomography) is recommended for those with an intermediate absolute risk. Angioplasty should be offered to patients with fibromuscular dysplasia. Whether intensive medical therapy (including an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker) for atherosclerotic renovascular hypertension is improved by angioplasty plus stent placement may be answered by ongoing studies, the largest of which may be the National Institutes of Health-funded Cardiovascular Outcomes in Renal Atherosclerotic Lesions (CORAL) trial.     

Renovascular hypertension in children

Renovascular disease is an uncommon but important cause of hypertension in children. It is usually diagnosed after a long delay because blood pressure is infrequently measured in children and high values are generally dismissed as inaccurate. Many children with renovascular disease have abnormalities of other blood vessels (aorta, cerebral, intestinal, or iliac). Individuals suspected of having the disorder can be investigated further with CT, MRI, or renal scintigraphy done before and after administration of an angiotensin-converting-enzyme inhibitor, but angiography is still the gold standard. Most children with renovascular disease will need interventional or surgical treatment. Endovascular treatment with or without stenting will cure or reduce high blood pressure in more than half of all affected children. Surgical intervention, if needed, should be delayed preferably until an age when the child is fully grown. Modern treatment provided by a multidisciplinary team of paediatric nephrologists, interventional radiologists, and vascular surgeons offers good long-term treatment results.     

Renovascular hypertension in blacks

To define the clinical characteristics of renovascular hypertension (RVH) and determine the clinical usefulness of captopril stimulated peripheral renin and postcaptopril renography in blacks at risk for RVH, 79 clinically selected hypertensive blacks were evaluated. Unstimulated (U-PRA), captopril stimulated (S-PRA) peripheral renin, and postcaptopril renography (PC-RENO) were obtained. All subjects underwent conventional renal arteriography. Renal artery stenosis (RAS) was present in 14 of 79 (18%) patients. Renovascular hypertension (RVH) was found in 7 of 79 (9%) patients. S-PRA had a sensitivity and specificity of 38% and 86% respectively to detect RAS; and a sensitivity and a specificity of 17% and 85% respectively to detect RVH. PC-RENO had a sensitivity and a specificity of 64% and 58% respectively to detect RAS; and a sensitivity and a specificity of 67% and 58% respectively to detect RVH. This study suggests that RAS occurs in 18% of clinically selected hypertensive blacks. RVH was present in 9% of this population. Captopril stimulated peripheral renin and postcaptopril renography are not useful as screening tools for the diagnosis of renovascular disease in blacks. Blacks at high risk should be evaluated with angiography.     

Renovascular illness: prevalence and therapy in patients with coronary heart disease

To explore the relationship between coronary artery disease and renal vascular disease, we performed renal arterial angiography in 609 patients undergoing coronary angiography for suspected coronary artery disease. We defined renal artery stenosis as nonsignificant (< 40%), borderline (40-60%) and significant (> 60%). One-hundred fifty-two patients had renal artery stenosis, while 457 did not. Two-hundred and ten patients had no coronary disease; of these, only 9 had renal artery stenosis. On the other hand, the 143 patients with renal artery stenosis, when subdivided, had similar degrees of coronary disease; three vessel disease was significantly more common than one or two vessel disease in all groups. Renal artery stenosis of all severity degrees was associated with common atherosclerotic risk factors. However, hypertension was not a clue to the presence of renal artery stenosis. To evaluate the effect of percutaneous revascularization on hypertension and renal function all 51 patients with significant renal artery stenosis were treated by primary stent implantation and were followed up for 6 months. Stent implantation showed a marked decrease in systolic and diastolic blood pressure (163 +/- 30 to 145 +/- 17 and 93 +/- 18 to 83 +/- 10 mmHg; p = 0.008) with a decrease in the amount of antihypertensive medication but without beneficial effect on serum creatinine during follow-up (1.46 +/- 0.70 mg/dl to 1.39 +/- 0.58 mg/dl, p = ns). We conclude that renal artery stenosis of any severity is strongly suggestive of three vessel coronary artery disease. The fact that renal stenting lowers blood pressure decreases antihypertensive drugs and increases medication flexibility in patients with coronary artery disease would support the notion of revascularization in patients with significant stenoses.     

Renovascular hypertension and coronary heart disease complicating essential thrombocythemia

A 36-year-old male was evalued for treatment-resistant hypertension.A high platelet count 828. 10⁹ l^–1, led to the diagnosisof essential thrombocythemia (ET). Aorto-renal angiography revealedcritical bilateral renal artery stenosis and coronary angiographyshowed three-vessel disease. Percutaneous transluminal renalangioplasty was only partially successful. The patient receiveda 12-week course of busulphan and subsequently the thrombocytecount decreased to 200. 10⁹ l^–1 Renal angiography 12 monthslater showed bilateral regression of the renal artery stenosiswith lowering of the blood pressure to normal levels.     

Renovascular hypertension associated with neurofibromatosis: a case report

Although vascular involvement in type 1 neurofibromatosis (NF1) is rare, it may lead to renal artery stenosis and renovascular hypertension (RVH). RVH may be treated using antihypertensive drugs, percutaneous transluminal renal angioplasty (PTRA), surgical reconstruction of the renal artery, or nefrectomy. In NF1 the results of PTRA are less predictable than in cases of fibromuscular dysplasia and atherosclerosis. We report a case of RVH associated with NF1. Despite administration of multiple antihypertensive drugs blood pressure remained uncontrolled. Selective left renal arteriography demonstrated two consecutive high-grade stenotic lesions with post-stenotic aneurysmal dilatation treated successfully with balloon dilatation. During the ensuing 2 year follow up complete normalization of blood pressure was observed. This case illustrates that endovascular therapy may be beneficial and should be considered a reasonable first option in these patients. However vascular involvement in NF may be progressive and therefore always requires continuing follow up.     

Intravascular ultrasound assessment of pulmonary vascular disease in patients with pulmonary hypertension.

BACKGROUND: Measurements of pulmonary pressure and resistance are still considered to be the "gold standard" in the evaluation of pulmonary hypertension (PH), despite their limitations in predicting irreversible disease. Hemodynamic assessment also only provides a global evaluation of the pulmonary vascular bed, whereas PH is an inhomogeneous disease of the vessel wall. METHODS AND RESULTS: We assessed the value of intravascular ultrasound (IVUS) in 30 patients with suspected PH and correlated the structural changes in distal pulmonary arteries found on IVUS with conventional hemodynamic data. Plasma endothelin (ET)-1 levels and pulmonary ET-1 extraction also were measured as markers of the severity of PH. The anatomic abnormalities revealed by IVUS were more severe in the lower lobes than in the upper lobes, as evidenced by the greater percentage of wall thickness (WT), the smaller lumen diameter/WT and lumen area/total vessel area (p < 0.05 for each). IVUS anatomic indexes correlated directly with hemodynamic data (eg, with pulmonary arterial systolic pressure; r = 0.56; p < 0.001) and ET-1 levels but inversely with pulmonary ET-1 extraction. CONCLUSION: Patients with PH have greater pulmonary arterial WT that is more severe in the lower lobes than in the upper lobes. The severity of structural abnormalities found on IVUS is directly correlated with hemodynamic findings and ET-1 levels. IVUS may provide useful additional information in the assessment of patients with PH.     

二维超声检测冠心病患者颈动脉粥样硬化病变

对103例经选择性冠状动脉造影的患者作双侧颈动脉超声检查，探讨了颈动脉超声检查的方法学以及颈动脉粥样硬化斑块的好发部位和超声分型，发现颈动脉粥样硬化斑块好发于颈动脉分叉处，以左侧多见，且多为扁平斑；颈动脉粥样硬化与冠状动脉粥样硬化之间有着密切的相关关系，冠状动脉病变支数越多，其颈动脉粥样硬化斑块积分也越高，不同冠状动脉病变组之间有非常显著的差异（P＜0．001）。