Renal Artery Involvement Research Articles

Spectrum of vascular pathology affecting patients with the antiphospholipid syndrome

A thrombotic microangiopathy that is identified in patients with the antiphospholipid syndrome (APS) represents only a part of the vascular pathology that can be associated with antiphospholipid antibodies (aPL). Tissues from two autopsies, four renal biopsies, two skin biopsies, and one amputated leg were obtained from six patients who met criteria for the diagnosis of APS. Three patients had systemic lupus erythematosus (SLE), one had lupus-like disease, and two had a primary APS. Five of the patients were hypertensive. Arteries of three patients disclosed fibrin thrombi along with widespread obstruction by recanalized intimal connective tissue. Small renal, leptomeningeal, and pulmonary arteries showed concentric cellular and fibrous intimal hyperplasia indistinguishable from hypertensive vascular disease. Glomerular capillary and afferent arteriolar thrombi were found in renal biopsies from two SLE patients. One of these SLE patients required a leg amputation in which the popliteal artery demonstrated thrombosis, intimal hyperplasia, and acute inflammation. The findings support clinical and experimental data that indicate aPLs cause thrombosis but suggest diversity in the pathogenetic mechanisms aPLs are capable of promoting. Inflammation seems to be rare and to accompany thrombosis. Intimal hyperplasia is particularly common. Its involvement of renal arteries may contribute to hypertension that develops in some APS patients.

Abdominal aortic aneurysms: assessment with gadolinium-enhanced time-of-flight coronal MR angiography (MRA)

A prospective study was performed to evaluate the efficacy of a gadolinium-chelate-enhanced MR angiography (MRA) using a coronal acquisition in the preoperative assessment of aneurysms of the abdominal aorta (AAA). Twenty patients with AAA were explored with MR using a two-dimensional (2D) time-of-flight MRA technique with a coronal acquisition, before and after intravenous administration of 0.1 mmol/kg of a gadolinium-chelate. Gadolinium-chelate-enhanced MRA with a coronal acquisition decreased deleterious saturation effects within aorta and iliac arteries in 16 of 20 patients (80%) and improved the overall quality of the images of the upper and lower parts of the AAA (i.e. extent of the aneurysm). Furthermore, gadolinium-chelate-enhanced MRA with a coronal acquisition allowed a better differentiation between slow flow and mural thrombus. Gadolinium-chelateenhanced MRA had a sensitivity of 100% and a specificity of 96% for evaluation of renal artery involvement, and a sensitivity of 93% and a specificity of 100% for iliac artery involvement. The results of this study show that gadolinium-chelate-enhanced MRA obtained with a coronal acquisition is efficacious for the preoperative assessment of AAA.

Abdominal aortic aneurysms: CT evaluation of renal artery involvement.

To determine whether computed tomography (CT) assessment of the proximal extent of ruptured aneurysms can help the surgeon determine whether to initially clamp the pararenal aneurysm neck or the supraceliac aorta. CT scans and medical records were reviewed and compared for 30 patients with ruptured abdominal aortic aneurysms (AAAs) who underwent immediate surgical repair. For 49 of 50 vessels in 25 patients, the authors correctly predicted at CT that AAAs originated caudal to the main renal artery origins. They also predicted that nine main renal arteries in five patients originated directly from the AAAs, but this was correct in only five arteries. Suprarenal clamping was required in all five patients. Infrarenal clamps were used before reconstruction in all 12 of the patients whose AAAs appeared to originate at least 30 mm below the main renal arteries. CT can help predict whether an initial aortic clamp can be placed caudal to the main renal artery orifices. Its use can be predicted with 100% certainty only when an aneurysm appears to originate at least 3 cm caudal to the origin of the main renal artery.

Abdominal Aortic Aneurysms in Females: A Comparative Analysis

The differences in nature, etiology, and outcome of abdominal aortic aneurysms (AAA) in females have received little attention. We retrospectively analyzed 23 females undergoing elective AAA repairs in the hands of one surgeon at Guthrie Clinic and compared them with agematched males from the same population undergoing elective AAA repairs over the same time period (19 years). AAAs were seen to have a male/female ratio of 8:1 and occur at a later age in females (73 years compared with 69 years). Females had less systemic atherosclerotic disease [coronary artery disease (CAD) in 15 males, 7 females; peripheral vascular disease (PVD) in 3 males, no females; cerebrovascular disease in 3 males, no females]. All other associated diseases were more common in females (hypercholesterolemia, 9 females, 1 male; hypertension, 15 females, 12 males; diabetes mellitus, 5 females, 3 males). Average aneurysm size was not significantly different (6.48 cm in females compared with 6.90 cm in males). Five females had significant renal artery involvement for which bypasses were done, whereas no males needed any procedures for renal arteries. There was no significant difference in postoperative morbidity and mortality. Long-term follow-up revealed a slight survival advantage for the males. The females with AAAs have more associated diseases (other than atherosclerosis) and have a decreased life expectancy.

The computed tomographic diagnosis of inflammatory abdominal aortic aneurysms

Amongst 1599 patients undergoing surgery for abdominal aortic aneurysm, there were 89 patients (5.6%) who showed typical features of inflammatory aneurysms of the abdominal aorta (IAAA). 37 of the 89 patients had been examined preoperatively by CT. In 73% of the cases (27/37) a correct diagnosis had been made. Localisation, width and extent of the IAAA was correctly diagnosed in all patients. Involvement of the renal arteries by the inflammatory process, the extent of thrombus and of mural calcification were accurately shown. The inflammatory tissues were typically ventral and lateral to the aorta. Frequently, there were adhesions to neighbouring structures. Aortic rupture, aortic dissection and retroperitoneal lymphoma may produce similar CT appearances; nevertheless, CT remains at present the method of choice for the diagnosis of IAAA because of its high sensitivity.

In situ replacement of infected vascular prostheses with rifampin-soaked vascular grafts: Early results

Based on the excellent results of experimental studies with antibiotic-bonded vascular prostheses for prevention of graft infection, gelatin-sealed grafts soaked with rifampin were implanted in situ in five patients with vascular infection. All patients were at risk for limb loss or death and could not be treated by standard techniques such as graft excision and extra-anatomic bypass. In one patient an infected aortic stump aneurysm with involvement of both renal and visceral arteries was found. He was treated by implantation of a bifurcation rifampin-soaked graft between the subdiaphragmal aorta and both renal arteries and reimplantation of celiac and superior mesenteric artery into the graft. In four patients with in-flow or runoff problems on angiography, an antibiotic-soaked graft was used for replacement of a partially or totally infected graft. Cultures were positive for Staphylococcus aureus in three and coagulase-negative staphylococci in two patients. Wound healing was uncomplicated; there was no need for amputation. After a follow-up of at least 6 months, all grafts were patent without any evidence of reinfection on computed tomographic scan. We conclude that infected vascular prostheses can be replaced in situ by rifampin-soaked grafts in patients at high risk for death or major amputation.

In situ replacement of infected vascular prostheses with rifampin-soaked vascular grafts: Early results

Based on the excellent results of experimental studies with antibiotic-bonded vascular prostheses for prevention of graft infection, gelatin-sealed grafts soaked with rifampin were implanted in situ in five patients with vascular infection. All patients were at risk for limb loss or death and could not be treated by standard techniques such as graft excision and extraanatomic bypass. In one patient an infected aortic stump aneurysm with involvement of both renal and visceral arteries was found. He was treated by implantation of a bifurcation rifampin-soaked graft between the subdiaphragmal aorta and both renal arteries and reimplantation of celiac and superior mesenteric artery into the graft. In four patients with in-flow or runoff problems on angiography, an antibiotic-soaked graft was used for replacement of a partially or totally infected graft. Cultures were positive for Staphylococcus aureus in three and coagulase-negative staphylococci in two patients. Wound healing was uncomplicated; there was no need for amputation. After a follow-up of at least 6 months, all grafts were patent without any evidence of reinfection on computed tomographic scan. We conclude that infected vascular prostheses can be replaced in situ by rifampin-soaked grafts in patients at high risk for death or major amputation.

Konventionelle und Cine-MRT bei Patienten mit Aneurysmen der Aorta abdominalis

We studied 40 patients with aneurysms of the abdominal aorta by MRI. These results were compared with those obtained by real-time sonography (n = 40), angiography (n = 32) and CT (n = 16). In 30 patients the imaging results were compared--as far as possible--with the operative findings. MRI proved more reliable, especially if compared with sonography, in evaluating renal or iliac artery involvement. Mural thrombi were detected more often (93%) by MRI than by CT (85%) or sonography (83%). Cine-MRI showed strong turbulences in 33%. Turbulences did not correlate with the size of the aneurysm.

Results of surgical treatment for atherosclerotic renovascular occlusive disease

In this study we retrospectively examined the results of surgery for atherosclerotic renal artery lesions and analysed the factors that may affect postoperative blood pressure response, changes in renal function and late mortality. A total of 326 patients were operated on over a 15 year period and were followed up for periods from 4 to 165 months (mean follow-up time: 37.2 months). An extra renal vascular area was also involved in 91.4% of cases and in 187 (57.3%) a significant involvement of both renal arteries was found and simultaneously treated. Combined revascularisation of other arteries was performed in 50.3% of patients. The indications for surgery were the treatment of extreme hypertension in 243 patients (74.5%), the improvement of renal function in 45 with renal insufficiency, and preservation of the kidney in 38 (11.7%). The preferred method of reconstruction was transaortic endarterectomy (236 cases, i.e. 72.4%) and postoperative angiography demonstrated a normal patent renal artery in 319 of 338 studied renal arteries (94.4%). There were no deaths in the early postoperative period after isolated renal artery reconstruction. Of the 164 patients with simultaneous renal and aortic reconstruction however 14 died during the early postoperative phase. The overall early mortality was thus 4.3% (14 out of 326 patients) and correlated significantly with the extent of the atherosclerotic disease, the age of the patients, the operative technique used and the different intra- and postoperative management during the two different periods of our experience (1974-1980 v. 1981-1989).(ABSTRACT TRUNCATED AT 250 WORDS)

Abdominal aortic aneurysm evaluation: Comparison of US, CT, MRI, and angiography

We studied 26 cases of abdominal aortic aneurysm with magnetic resonance imaging (MRI), computed tomography (CT), ultrasonorography (US), and angiography. Data acquired were compared to those obtained at surgery. Diameter of the aneurysm was correctly defined in all cases by CT and MRI, while angiography underestimated the diameter of lesions without peripheral calcifications. Involvement of renal arteries was present in four cases and correctly diagnosed with MRI and angiography in all of them. CT did provide this information in three cases and US were not useful. Also, iliac arteries involvement was depicted by CT, MRI, and angiography in 10 out of 10 patients. Coronal sections of MRI provided comparable images to those of angiography. By comparing these different techniques we verified the good reliability of MRI as investigation tool for an accurate evaluation of aneurysms; its only limit lying in the poor capability of detecting calcifications.

Radionuclide renography predicts functional changes in patients with renal artery involvement by Takayasu’s arteritis

Renovascular hypertension is a major complication of Takayasu's arteritis, which contributes to the high mortality associated with the disease. We studied 5 patients affected by different degrees of Takayasu's arteritis to assess the usefulness of radionuclide renography in evaluating renal perfusion and function, and to predict changes induced by the disease before and after therapeutic interventions. Computer-assisted dynamic renal imaging with Tc-99m diethylenetriaminepentaacetic acid (DPTA) and I-131 orthoiodohippurate (OIH), and renal arteriography were concurrently performed in all patients. Two patients with hemodynamically insignificant renal artery stenosis showed normal perfusion and function by renography. Three patients had significant renal artery stenosis and functional changes on renography. Subsequently, two of these patients had successful therapy (one had bilateral renal artery bypass grafts, and the other had renal artery angioplasty), and both showed functional improvement at renography. Our results demonstrate that radionuclide renography is valuable in the assessment of functional changes induced by Takayasu's arteritis as well as for determining the response to therapeutic interventions.

Acute aortic occlusion

Acute aortic occlusion is a rare and emergent vascular event. Patients who present with this disorder have a classical history and physical examination consistent with occlusion of the distal aorta and resultant ischemia to the distal tissues. Time is of the essence in dealing with these patients. Aortography proved to be important in determining renal artery involvement in our patients. Based on this finding, we suggest that preoperative arteriograms be obtained. The method of treating these patients after arteriography should be to move quickly to the operating room. Patients with renal artery occlusion must be seriously considered for primary revascularization with either aortofemoral or aortoiliac reconstruction and thrombectomy or bypass of the occluded renal artery. If no renal artery involvement is revealed on arteriography, the initial operation should include an attempt to reestablish inflow by retrograde femoral thromboembolectomy under local anesthesia. If that fails, a decision must be made based on the patient's clinical status, whether a major vascular procedure would be tolerated. If so, primary revascularization or transabdominal thrombectomy should be attempted. If the patient is deemed unable to tolerate a major vascular procedure, then axillobifemoral bypass under local anesthesia should be performed. Postoperatively, the patient should be aggressively managed to prevent pulmonary and renal complications. Even with aggressive surgical management and postoperative care, these patients have an uncertain postoperative course. It is of primary importance that physicians realize that time is a critical factor and these patients must be referred to the appropriate care center promptly. Only by ensuring prompt surgical management can a mortality rate of less than 50 percent be expected.

Middle aortic syndrome. Effectiveness and durability of complex arterial revascularization techniques.

Middle aortic syndrome typically occurs as severe hypertension in young patients who have weak or absent femoral pulses and an abdominal bruit. It results from a diffuse narrowing of the distal thoracic and abdominal aorta, commonly involving the visceral and renal arteries. The clinical presentation, angiographic assessment, and surgical outcome of 10 patients (mean age: 19.5 years) who underwent one-stage revascularization for middle aortic syndrome were reviewed to determine the effectiveness and durability of one-stage revascularization techniques to relieve these complications. All patients were hypertensive (mean blood pressure: 176 mmHg); six (60%) had severe, poorly controlled hypertension, two of whom had previous failed operations for renovascular hypertension and one who presented with malignant hypertension and acute renal failure. Five patients had disabling myocardial insufficiency, only one of whom had documented coronary artery disease. Four patients had intermittent claudication. Aortography showed variable length high-grade midaortic stenosis, nine had visceral artery involvement, and eight had renal artery involvement. All patients underwent one-stage revascularization by a variety of autogenous and prosthetic techniques. The postoperative recovery was uncomplicated in eight of nine patients and was often associated with dramatic reduction in blood pressure. There was a single death from disruption of the thoracic anastomosis in a patient who had diffuse cystic medial necrosis of the aorta. Arterial biopsy in nine patients indicated evidence for both acquired and congenital origins of the midaortic stenosis. Late follow-up evaluation (mean: 4.1 years) showed normal growth and development, preservation of renal function, and relief of myocardial insufficiency in all patients. Seven patients (77%) are cured of their hypertension, and two (23%) have only mild hypertension. These results indicate that one-stage revascularization of patients with middle aortic syndrome can result in effective and durable relief of these severe life-threatening complications.

Juxtarenal infrarenal abdominal aortic aneurysm. Special diagnostic and therapeutic considerations.

Juxtarenal infrarenal abdominal aortic aneurysms are defined as those aneurysms that involve the infrarenal abdominal aorta adjacent to or including the lower margin of renal artery origins. The misinterpretation of findings at exploratory operation or special studies may suggest renal artery involvement and result in abandonment of operation and/or referral to distant centers, thus delaying treatment. This report is concerned with 101 patients with a median age of 68 who had such aneurysms, all referred with a diagnosis of renal or visceral arterial involvement either after exploratory operation (32), because of aneurysmal size (12), or due to misinterpretation of special studies (57). Computed tomographic (CT) scans, ultrasounds, and aortograms in the anterio-posterior projection frequently suggested renal artery involvement due to the fact that the upper end of aneurysm frequently lay over the renal artery origins due to infrarenal aortic elongation and buckling of the aorta at the renal artery level. The true nature of the lesion was best demonstrated by aortography performed in the lateral position. The operation producing the best results was one performed through a midline abdominal incision. The aorta is cross-clamped at the diaphragm and the proximal anastomosis is performed from inside the aneurysm at the renal artery level. The graft then is clamped and the other clamp removed to restore flow in the visceral vessels while the distal anastomosis is completed. Early survival occurred in 93% of patients employing the operation, despite the fact that other conditions frequently were present: renal insufficiency in 19, rupture in seven, renal artery occlusive disease in 20, chronic obstructive pulmonary disease in 34, and hypertension in 77.

Abdominal aortic aneurysm in a premature neonate with disseminated candidiasis: ultrasound and angiography

When using ultrasound for detection of kidney enlargement, we found an acute abdominal aortic aneurysm secondary to aortitis following umbilical artery catheterisation in a premature neonate with systemic candidiasis. Aortography was performed to provide vascular details such as involvement of celiac, renal, iliac and femoral arteries.

Spectrum of renovascular hypertension in the young in north India: a hospital based study on occurrence and clinical features.

Occurrence of renovascular hypertension and its etiology is described in this work as seen in north India. Out of 2395 young hypertensives admitted for evaluation during the years 1978-1983, 91 patients (3.8%) were found to be having renovascular hypertension. In all patients suspected diagnosis of RVH was confirmed by the angiography of aorta and main vessels. Idiopathic aortoarteritis, diagnosed in 54 patients (59.4%) was the commonest cause of renovascular hypertension. In this group renal arterial involvement was found to be bilateral in 26 patients. Twenty-eight patients had isolated renal artery stenosis of unknown etiology. Six had fibromuscular dysplasia, 2 had polyarteritis and one had renal artery aneurysm. Twenty-three patients underwent surgery which included autotransplantation, arterial by-pass and nephrectomy with improved blood pressure control in 15. It is concluded that aortoarteritis seems to be the major cause of renovascular hypertension in the young in this part of the world.

Concomitant renal revascularization in patients undergoing aortic surgery.

Sixty-three patients who underwent renal revascularization at the time of aortic surgery were retrospectively reviewed. These patients had significant renal artery stenosis in addition to either severe aortoiliac occlusive disease or aortic aneurysmal disease. Fifty-eight patients were hypertensive, whereas five patients were normotensive and these renal lesions were treated prophylactically. The operative mortality rate was 3%. Despite lack of selectivity in these patients with diffuse atherosclerosis, 60% (35 of 58) of the patients with hypertension could be classified as either "cured" or "improved." Patients with bilateral renal artery involvement and moderate azotemia were noted to improve with respect to renal function postoperatively. No patient has required chronic dialysis at a mean follow-up period of 22.6 months. Simultaneous aortic and renal artery surgery may be performed with low morbidity and mortality rates and produce a gratifying improvement in hypertension. Renal functional improvement and perhaps preservation of renal mass may be anticipated in selected patients.

Concomitant renal revascularization in patients undergoing aortic surgery

Sixty-three patients who underwent renal revascularization at the time of aortic surgery were retrospectively reviewed. These patients had significant renal artery stenosis in addition to either severe aortoiliac occlusive disease or aortic aneurysmal disease. Fifty-eight patients were hypertensive, whereas five patients were normotensive and these renal lesions were treated prophylactically. The operative mortality rate was 3%. Despite lack of selectivity in these patients with diffuse atherosclerosis, 60% (35 of 58) of the patients with hypertension could be classified as either “cured” or “improved.” Patients with bilateral renal artery involvement and moderate azotemia were noted to improve with respect to renal function postoperatively. No patient has required chronic dialysis at a mean follow-up period of 22.6 months. Simultaneous aortic and renal artery surgery may be performed with low morbidity and mortality rates and produce a gratifying improvement in hypertension. Renal functional improvement and perhaps preservation of renal mass may be anticipated in selected patients.

Management of Renovascular Problems During Aortic Operations

• Sixty patients who had primary aortic disease (aortic stenosis or aneurysm) and required simultaneous aortic and renal artery operations were divided according to the indications for renal artery repair as follows: group 1, renovascular hypertension (ten patients); group 2, kidney salvage (11 patients); group 3, improvement of renal function (three patients); and group 4, renal artery involvement in the diseased aorta (36 patients). Renal artery reimplantation and aortorenal grafting were usually employed. Two kidneys in the renal salvage group failed, and two main and three accessory arteries were found to be occluded on late follow-up. Three patients died after emergency surgery for aneurysm rupture (two patients) and infected false aneurysm (one patient). The mortality rate for combined operations is higher (5%) than for aortic or renal surgery alone, but simultaneous repair may be needed for technical reasons, or to treat renovascular disease. ( Arch Surg 1984;119:681-685)

Marginal artery of Drummond in aorto-arteritis.

SUMMARYEight cases of aorto‐arteritis with narrowing of the abdominal aorta showed a marginal artery of Drummond on aortography. There was no case with clinical evidence of abdominal angina. In six cases there was occlusion or narrowing of the superior mesenteric artery with flow of blood in the marginal artery from the inferior to the superior mesenteric artery and these patients also had hypertension resulting from involvement of renal artery/arteries. The other two patients with involvement of the inferior mesenteric artery, showed the marginal artery being filled from the superior mesenteric artery and were normotensive since there was no renal artery involvement. There were only four patients in whom the aortic arch or its branches were also involved. Two patients had evidence of active pulmonary tuberculosis.