Management of ischemic nephropathy: dialysis-free survival after surgical repair

PURPOSE: This retrospective review describes the surgical management of consecutive patients with severe hypertension and ischemic nephropathy due to atherosclerotic renovascular disease. METHODS: From January 1987 through December 1998, a total of 590 patients underwent operative renal artery repair at our center. A subgroup of 232 hypertensive patients (97 women, 135 men; mean age, 66 +/- 8 years) with atherosclerotic renovascular disease and preoperative serum creatinine levels of 1.8 mg/dL or more forms the basis of this report. Change in renal function was determined from glomerular filtration rates estimated from preoperative and postoperative serum creatinine. The influence of selected preoperative parameters and renal function response on time to dialysis and dialysis-free survival was determined by a proportional hazards regression model. RESULTS: In all, 83 patients underwent unilateral renal artery repair and 149 patients underwent bilateral repair, including repair to a solitary kidney in 17 cases. A total of 332 renal arteries were reconstructed, and 32 nephrectomies were performed in these patients. After surgery, there were 17 deaths (7.3%) in the hospital or within 30 days of surgery. Advanced patient age (P =.001; hazard ratio, 1.1; 95% CI [1.1, 1.2]) and congestive heart failure (P =.04; hazard ratio, 2.9 CI [1.0, 8.6]) demonstrated significant and independent associations with perioperative mortality. With a change of 20% or more in EGFR being considered significant, 58% of patients had improved renal function, including 27 patients removed from dialysis dependence; function was unchanged in 35% and worsened in 7%. Follow-up death from all causes or progression to dialysis dependence demonstrated a significant and independent association with early renal function response. Both patients whose function was unchanged (P =.005; hazard ratio, 6.0; CI [2.2, 16.6]) and patients whose function was worsened (P =.03; hazard ratio, 2.2; CI [1.1, 4. 5]) remained at increased risk of death or dialysis dependence. For patients with unchanged renal function after operation, risk of death or dialysis demonstrated a significant interaction with preoperative renal function. In addition to severe preoperative renal dysfunction, diabetes mellitus demonstrated a significant and independent association with follow-up death or dialysis. CONCLUSION: Surgical correction of atherosclerotic renovascular disease can retrieve excretory renal function in selected hypertensive patients with ischemic nephropathy. Patients with improved renal function had a significant and independent increase in dialysis-free survival in comparison with patients whose function was unchanged and patients whose function was worsened after operation. These results add further evidence in support of a prospective, randomized trial designed to define the value of renal artery intervention in patients with ischemic nephropathy.     

Surgery after failed percutaneous renal artery angioplasty.

PURPOSE: This retrospective review describes the surgical management of 51 patients after failed percutaneous renal artery angioplasty (F-PTRA). METHODS: From January 1987 through June 1998, 51 consecutive patients underwent surgical repair of either atherosclerotic (32 patients) or fibromuscular dysplastic (FMD; 19 patients) renovascular vascular disease after F-PTRA. These patients form the basis of this report. Surgical repair was performed for hypertension (29 patients with atherosclerosis: mean blood pressure, 205 +/- 34/110 +/- 23 mm Hg; 18 patients with FMD: mean blood pressure, 194 +/- 24/118 +/- 18 mm Hg) or ischemic nephropathy (20 patients with atherosclerosis: mean serum creatinine level, 2.0 +/- 0.8 mg/dL; three patients with FMD: mean serum creatinine level, 2.0 +/- 1.1 mg/dL). Emergency operation was required in four patients for acute renal artery thrombosis (one patient with atherosclerosis, one patient with FMD), renal artery rupture (one patient with atherosclerosis), or infected pseudoaneurysm (one patient with atherosclerosis). Operative management, blood pressure and renal function response to operation, and dialysis-free survival rate were examined and compared with 487 patients (441 patients with atherosclerosis, 46 patients with FMD) treated by operation alone. RESULTS: Among the patients with atherosclerotic renovascular disease, there were three postoperative deaths (9.4%) after repair for F-PTRA. Secondary operative repair was associated with emergent repair or nephrectomy in 16% of cases, while more extensive renal artery exposure and more complex operative management was required in 50% of patients with atherosclerosis and 65% of patients with FMD repaired electively. Among the 28 operative survivors with hypertension and atherosclerotic renovascular disease, blood pressure benefit after F-PTRA was significantly lower when compared with patients with atherosclerosis who underwent treatment with operation only (57% vs 89%; P <.001). However, blood pressure benefit in the 19 patients with FMD did not differ (89% vs 96%). Among the 28 patients with atherosclerosis, preoperative estimated glomerular filtration rate (EGFR) as compared with postoperative EGFR was significantly increased (47.4 +/- 4.2 mL/min/1.73m(2) vs 56. 6 +/- 5.1 mL/min/1.73m(2); P =.002). However, EGFR prior to PTRA was not significantly different from postoperative EGFR (51.6 +/- 3.4 mL/min/1.73m(2) vs 56.6 +/- 4.9 mL/min/1.73m(2); P =.121). As compared with patients with atherosclerosis who underwent treatment with operation alone, there was no difference in the dialysis-free survival rate. CONCLUSION: Operative repair after F-PTRA was altered in 59% of the patients with atherosclerosis and in 68% of patients with FMD. Blood pressure benefit for patients with FMD was unchanged after F-PTRA. However, the blood pressure benefit was significantly decreased among patients with atherosclerosis. Decreased EGFR after F-PTRA was recovered with operative renal artery repair. However, postoperative EGFR as compared with EGFR prior to PTRA was unchanged. Blood pressure and renal function response after F-PTRA for atherosclerotic renovascular disease warrants further study.     

Preservation of renal function with surgical revascularization in patients with atherosclerotic renovascular disease

OBJECTIVE: Clinical and anatomic factors predictive of a favorable response to renal revascularization performed for renal function salvage remain poorly defined. To clarify decision making in such patients we reviewed a contemporary experience of surgical renal artery revascularization (RAR) performed primarily for preservation of renal function. METHODS: Between June 1990 and March 2001 (ensuring 1 year minimum follow-up), 96 patients with renal insufficiency (serum creatinine [Cr] concentration >or=1.5 mg/dL) and hypertension underwent RAR for preservation of renal function. Study end points included early and late renal function response, progression to dialysis dependence, and long-term survival. Variables potentially associated with these end points were assessed with univariate analysis, Cox regression analysis, and logistic regression analysis, and survival was assessed with the Kaplan-Meier method. RESULTS: Perioperative failure of RAR occurred in 3 patients (3%), with perioperative mortality in 4 patients (4.1%); thus 92 patients were available for long-term follow-up (mean, 39 months). Mean patient age was 70 +/- 9 years with a mean baseline Cr of 2.6 mg/dL (range, 1.5-7.8 mg/dL). Operative management consisted of aortorenal bypass in 38% of patients, extraanatomic bypass in 38% of patients, and endarterectomy in 24% of patients; 32% of patients required combined aortic revascularization and RAR, and 27% underwent bilateral RAR. At hospital discharge renal function had improved (20% decrement in Cr) in 41 (43%) patients, including 7 patients who were removed from dialysis; remained unchanged in 40 (41%) patients; and declined (20% increase in Cr) in 15 (16%) patients. At last follow-up renal function was either improved or unchanged in 72% of patients. Predictors of a favorable response to RAR at last follow-up included stable Cr at hospital discharge (odds ratio [OR], 7.1; 95% confidence interval [CI], 2.5-21.8; P =.0004) and decreased Cr at hospital discharge (OR, 16; 95% CI, 1.6-307.8; P <.0001); bilateral renal artery repair (OR, 3.1; 95% CI, 0.9-10.6; P =.07) approached clinical significance. Predictors of worsened excretory function at last follow-up included decline of renal function at hospital discharge (OR, 28.9; 95% CI, 5.0-165.4; P =.0002), intervention to treat unilateral renal artery stenosis (OR, 3.8; 95% CI, 0.8-16.6; P =.05), and level of baseline Cr (OR, 3.0; 95% CI, 1.0-4.0; P =.04). Progression to dialysis occurred in 16 (17%) patients. Dialysis-free survival at 5 years was 50%, and overall actuarial survival at 5 years was 59%. Predictors of progression to dialysis during follow-up included treatment of complete renal artery occlusion (OR, 6.2; 95% CI, 1.3-29.5; P =.02), early failure of RAR (OR, 3.1; 95% CI, 0.7-14.2; P =.04) and baseline Cr (OR, 2.9; 95% CI, 1.3-6.1; P =.006). CONCLUSION: Long-term clinical success in the preservation of renal function, noted in 70% of patients, can be predicted by the initial response to RAR and by anatomic factors, in particular, bilateral repair. While extreme (mean Cr >or=3.2 mg/dL) renal dysfunction generally is predictive of poor long-term outcome, a subset of patients will experience favorable results, even to the extent of rescue from dialysis. These results may facilitate clinical decision making in the application of RAR for renal function salvage.     

Renal artery repair: consequence of operative failures.

OBJECTIVE: This report examines the blood pressure and renal function response in 20 consecutive patients after secondary renal revascularization following failed operative repair. SUMMARY BACKGROUND DATA: Most reports describing operative failure of renal artery (RA) repair emphasize the technical aspects of redo RA reconstruction and the immediate blood-pressure response to secondary operation. This report examines the eventual renal function and estimated survival after secondary intervention. METHODS: Primary methods of RA reconstruction, primary blood pressure and renal function responses, and causes of failed RA repair were defined for 20 patients requiring reoperation for recurrent hypertension or renal insufficiency. These parameters were compared with secondary procedures and eventual blood pressure and renal function response. The eventual outcome for these 20 patients was compared with 514 patients managed by primary renal revascularization during the same period. RESULTS: Failure of primary RA repair correlated with complex fibromuscular dysplasia requiring branch ex vivo reconstruction (p = 0.020). RA thrombosis frequently required nephrectomy (83%), whereas RA stenosis was successfully reconstructed (91 %; p = 0.001). Primary and secondary blood-pressure responses were equivalent (94% vs. 95% cured or improved); however, primary and eventual renal function responses differed significantly (p = 0.015), with seven patients dialysis-dependent on follow-up. Eventual dialysis dependence was associated with preoperative azotemia (p = 0.022), bilateral failure of primary RA repair (p = 0.007), and an increased risk of follow-up death (p = 0.002). Considering all 534 patients, failed RA repair demonstrated a significant and independent association with eventual dialysis dependence and decreased dialysis-free survival. CONCLUSIONS: Contemporary rates of reoperation after surgical RA repair are low. In properly selected patients, beneficial blood-pressure response is reliably observed after both primary and secondary operative procedures. However, secondary procedures are associated with a significant and independent risk of eventual dialysis dependence.     

Contemporary results of juxtarenal aneurysm repair

OBJECTIVE: The increasing use of aortic endografts predictably will add to the complexity of open abdominal aortic aneurysm (AAA) repair and, therefore, the proportion of surgically treated infrarenal AAAs that are juxtarenal in location (JRA) will grow. This study reviews a single-center experience with JRAs. METHODS: Between June 1994 and December 2000, 138 patients underwent elective repair of a JRA, comprising 16.1% of 859 consecutive asymptomatic and intact symptomatic nonruptured infrarenal AAAs repaired over the same period. All patients with JRA needed proximal suprarenal clamping (SRC) or supravisceral (SVC) clamping. Patient demographics, selected risk factors, and operative details were recorded. Univariate analyses of selected risk factors for an adverse perioperative event were assessed, and multivariate analyses were performed with linear and logistic regression with backwards selection. RESULTS: SRC was used in 95 patients (69%), and 43 patients (31%) underwent SVC. The mortality rate was 5.1% (7/138) for JRA repair, and 2.8% (20/720) for infrarenal AAA repair (P =.03). The mortality rate was significantly greater for those patients who received SVC compared with SRC (11.6% versus 2.1%; P =.02). Multivariate analysis identified SVC position as the only independent predictor of mortality (odds ratio [OR], 6.1; 95% CI, 1.1 to 32.9; P =.035). Transient renal insufficiency occurred in 39 patients (28.3%), but only eight patients (5.8%) needed dialysis. Patients who had SVC had a significantly greater rate of renal insufficiency than those who received SRC (41.9% versus 22.1%; P =.02). Multivariate analysis showed SVC position (OR, 3.3; 95% CI, 1.4 to 7.8; P =.008), diabetes (OR, 3.7; 95% CI, 1.1 to 12.9; P =.04), and preoperative renal insufficiency (OR, 5.8; 95% CI, 2.2 to 15.4; P <.001) were independent predictors of postoperative renal insufficiency. Renal ischemia during proximal clamping cannot alone explain renal complications because clamp time was shorter in patients with SVC (24.9 +/- 2.4 minutes versus 32.2 +/- 1.5 minutes; P =.009). CONCLUSION: JRA repair can be accomplished with a low mortality rate, but a more proximal clamp position may adversely affect outcome in these patients. Postoperative renal insufficiency is related to diabetes, preoperative renal insufficiency, and SVC position. These results suggest SRC is safer than SVC for proximal aortic clamp control of JRAs. Although clamp level must be tailored to patient anatomy, outcome may be improved if the clamp level can be kept distal to the superior mesenteric artery origin.     

Branch renal artery repair with cold perfusion protection

PURPOSE: This retrospective review describes the use and clinical outcome of cold perfusion protection during branch renal artery (RA) repair in 77 consecutive patients. METHODS: From July 1987 through November 2006, 874 patients had open operative RA repair to 1312 kidneys. Seventy-seven patients (62 women, 15 men; mean age, 44 +/- 17 years) had branch RA reconstruction using ex vivo or in situ cold perfusion protection for 78 kidneys. Demographic data and surgical technique were examined. Blood pressure response and renal function were estimated. Patency of repair was determined by angiography and renal duplex ultrasound (RDUS) imaging. Primary RA patency was estimated by life-table methods. RESULTS: Seventy-eight RAs were repaired using ex vivo (49 kidneys) or in situ (29 kidneys) cold perfusion protection. Bilateral RA repair was performed in eight patients, with 13 repairs to solitary kidneys. RA disease included aneurysm (RAA) in 50, fibromuscular dysplasia (FMD) in 37, atherosclerosis in 5, and arteritis in 2; 16 patients had both FMD and RAA. Hypertension was present in 93.5% (mean blood pressure, 184 +/- 35/107 +/- 19 mm Hg; mean of 1.9 +/- 1.1 drugs). RA repair included bypass using saphenous vein in 69, hypogastric artery in 3, polytetrafluoroethylene (PTFE) in 2, composite vein/PTFE in 2, cephalic vein in 1, or aneurysmorrhaphy in 1. The eight bilateral RA repairs were staged. One patient required bilateral cold perfusion protection. One planned nephrectomy was performed at the time of contralateral ex vivo reconstruction. No primary nephrectomies were required for intended reconstruction. Each RA reconstruction required branch dissection and reconstruction (mean of 2.8 +/- 1.6 branches were repaired). Mean cold ischemia time was 125 +/- 40 minutes. Each kidney was reconstructed in an orthotopic fashion. Five early failures of repair required three nephrectomies and one operative revision. Based on postoperative angiography or RDUS, or both, primary patency of RA repair at 12 months was 85% +/- 5%; assisted primary patency was 93% +/- 4%. Among patients with preoperative hypertension, 15% were cured, 65% were improved, and 20% were considered failed. Early renal function was improved in 35%, unchanged in 48%, and worse in 17%. Four patients had perioperative acute tubular necrosis. No patient progressed to dialysis-dependence. CONCLUSION: Both ex vivo and in situ cold perfusion protection extend the safe renal ischemia time for complex branch RA repair and avoid the need for nephrectomy.     

Risk factors for autogenous infrainguinal bypass occlusion in patients with prosthetic inflow grafts

OBJECTIVE: In patients with prosthetic inflow (PI) grafts the proximal anastomosis of autogenous infrainguinal bypass (AIB) can be placed on the PI or on a distal native vessel in the groin. This study was performed to determine the effect of placement of an AIB proximal anastomotic site in a patient with ipsilateral PI. METHODS: Patients undergoing AIB and PI between January 1990 and July 2002 were included in the study. They were classified into two groups on the basis of location of the proximal anastomosis. In group 1 the AIB proximal anastomosis was placed on the PI in the groin, whereas in group 2 the AIB proximal anastomosis was placed on a distal native groin artery. Patency, limb salvage, and patient survival in the two groups were calculated with the Kaplan-Meier method. The Cox proportional hazards model was used to determine independent risk factors affecting AIB patency. RESULTS: Two hundred twenty-nine patients underwent AIB and PI. In group 1, 23 AIBs became thrombosed concurrent with 26 PI occlusions, and in group 2, 7 AIBs became thrombosed concurrent with 36 PI occlusions (P <.001). Five-year assisted primary patency, limb salvage, and patient survival in groups 1 and 2 were 50% and 75% (P <.001, log-rank test), 78% and 90% (P =.005, log-rank test), and 56% and 69% (P = NS, log-rank test), respectively. Factors independently associated with AIB occlusion are hypertension (hazard ratio [HR], 3.41; 95% confidence interval [CI], 1.65-7.05; P =.001), postoperative warfarin sodium therapy (HR, 1.86; 95% CI, 1.07-3.23; P =.03), continued smoking (HR, 1.72; 95% CI, 0.93-3.18; P =.08), AIB arising from PI (HR, 2.38; 95% CI, 1.35-4.18; P =.003), and PI occlusion (HR, 3.70; 95% CI, 2.15-6.36; P <.001). CONCLUSION: A proximal AIB anastomosis located directly on the PI is an independent risk factor for decreased AIB patency of equal or greater importance than current smoking, hypertension, or PI occlusion. The proximal anastomosis of an AIB in a patient with an ipsilateral PI should be placed on a distal native artery.     

Transient advanced mental impairment: an underappreciated morbidity after aortic surgery

OBJECTIVES: To determine the incidence, risk factors, and associated morbidity of transient advanced mental impairment (TAMI) after aortic surgery. METHODS: We retrospectively studied the charts of 188 consecutive patients undergoing elective aortic reconstruction during a recent 6-year period at a university hospital. All patients were lucid on admission and nonintubated at the time of evaluation at least 2 days after operation. TAMI was defined as disorientation or confusion on 2 or more postoperative days. Preoperative, intraoperative, and postoperative clinical variables were examined statistically for associations with TAMI. RESULTS: Fifty-three patients (28%) had development of TAMI 3.9 plus minus 2.8 days after operation. Stepwise logistic regression analysis selected the following independent predictors for TAMI: age >65 years (odds ratio [OR], 7.9; 95% confidence interval [CI], 2.7 to 23.7), American Society of Anesthesiology physical status classification >3 (OR, 2.8; 95% CI, 1.3 to 5.9), diabetes mellitus (OR, 3.4; 95% CI, 1.2 to 9.8), old myocardial infarction (OR, 2.4; 95% CI, 1.1 to 5.3), and hypertension (OR, 2.3; 95% CI, 1.0 to 5.3). Alcohol consumption was not significantly associated with TAMI. In the postoperative period, patients with TAMI were more likely to have hypoxia (P <.001), a need for reintubation (P <.001), pneumonia (P <.001), congestive heart failure (P =.003), and kidney failure (P =.05). In addition, patients with TAMI had a longer duration of endotracheal intubation (3.7 plus minus 7.8 vs 0.6 plus minus 1.2 days, P <.001), stay in the intensive care unit (8.9 plus minus 9 vs 3.9 plus minus 2 days, P <.001), and postoperative hospital stay (14.8 plus minus 11 vs 9.2 plus minus 5 days, P <.001) than patients without TAMI. Twenty (38%) patients with TAMI were discharged to intermediate-care facilities, compared with 11 (8%) patients without TAMI (P <.001). Postoperative variables conferring the largest relative risks for development of TAMI included oxygen saturation less than 92% (5.4), the need for reintubation (3.3), congestive heart failure (3.3), and pneumonia (3.2). TAMI, conversely, conferred the largest relative risks for development of postoperative congestive heart failure (15.3), the need for reintubation (9.3), pneumonia (7.1), and the need for ICU readmission (3.8). CONCLUSIONS: These data show that TAMI is prevalent among patients undergoing aortic reconstruction and is associated with dramatically increased morbidity and postoperative hospitalization rates.     

Early and long-term results of percutaneous transluminal angioplasty of the lower abdominal aorta.

PURPOSE: The purpose of this study was to determine the early and long-term results of percutaneous transluminal angioplasty (PTA) of atherosclerotic lower abdominal aorta stenosis. METHODS: This study was performed as a retrospective study. From 1980 to 1997, 46 patients with chronic lower limb ischemia with moderate to severe claudication as the result of isolated infrarenal disease or aortoiliac disease underwent PTA. All patients underwent angiography before and after angioplasty and Doppler ultrasound scan examination with ankle-brachial index determination. No stents were used. RESULTS: The technical success rate was 96% (44 of 46 cases). Thirty-eight patients (83%) immediately showed clinical, hemodynamic, and angiographic improvement. The initial success rate for patients with isolated infrarenal or bifurcation disease was 92%, whereas it was 71% for aortoiliac disease. Among the eight patients with no initial improvement, four had clinical deterioration and two required emergency surgical revascularization. There were no other complications. Fifty-six percent of the patient conditions (95% confidence interval [CI], 38% to 74%) remained clinically improved at the 5-year follow-up examination. Recurrence of symptoms was caused by femoropopliteal disease in most patients. The primary patency rate assumed with maintenance of hemodynamic improvements was 70% (95% CI, 52% to 88%) and 64% (95% CI, 44% to 84%) at 4 and 5 years of follow-up, respectively. The primary patency rate at 4 years for patients with isolated infrarenal or bifurcation disease was 83% (95% CI, 64% to 100%), whereas it was 55% for aortoiliac disease (95% CI, 30% to 80%; P =.06) The variables that were statistically predictive of patency failure were poor runoff (P =. 01) and presence of aortoiliac atherosclerotic disease (P =.04). CONCLUSION: Our results suggest that PTA is an excellent treatment for chronic arterial insufficiency of the lower extremities as the result of isolated atherosclerotic lower abdominal aortic occlusive lesions because of good long-term patency. Aortic PTA for those patients with iliac involvement or with poor runoff gives acceptable results but carries lower patency and clinical success rates.     

Surgical management of dialysis-dependent ischemic nephropathy

Purpose: This retrospective review describes surgical management of dialysis-dependent ischemic nephropathy.Methods: From February 1987 through September 1993, 340 patients underwent operative renal artery (RA) reconstruction at our center. A subgroup of 20 patients (6 women; 14 men; mean age 66 years) dependent on hemodialysis immediately before RA repair form the basis of this report. Glomerular filtration rates (EGFR) were estimated from at least three serum creatinine measurements obtained 26 weeks before and after operation. A linear regression model was used to estimate the mean rate of change of EGFR before and after RA repair. Comparative analysis of kidney status and change in EGFR were performed. The influence of function response on follow-up survival was determined by the product-limit method.Results: Hemodialysis was discontinued in 16 of 20 patients (80%). For these 16 patients, postoperative EGFR ranged from 9.0 to 56.1 ml/min/1.73 m² (mean 32.4 ml/min/1.73 m²). Two of 16 patients resumed hemodialysis 4 and 6 months after surgery. Discontinuation of dialysis was more likely after bilateral or complete RA repair (15 of 16 patients) versus unilateral repair (one of four patients; p = 0.01). Permanent discontinuation of dialysis was associated with a rapid preoperative rate of decline in EGFR (mean slope log_e EGFR: -0.1393 ± 0.0340 without dialysis; -0.0188 ± 0.0464 with dialysis; p = 0.04, but NS after controlling for multiple comparisons). Immediate increase in EGFR after operation was inversely correlated with the severity of nephrosclerosis (rank correlation: -0.57; 95% confidence interval [ -0.83, -0.10]). Follow-up death was associated with dialysis dependence; two deaths occurred among 14 patients not receiving dialysis, whereas five of six patients dependent on dialysis died (p < 0.01).Conclusion: Surgical correction of ischemic nephropathy can retrieve renal function in selected patients dependent on dialysis characterized by a rapid decline in preoperative EGFR in combination with global renal ischemia treated by complete or bilateral renal revascularization. After RA repair, discontinuation of dialysis may be associated with improved survival rates when compared with continued dialysis dependence. (J VASC SURG 1995;21:197-211.)     

The relationship between aortic wall distensibility and rupture of infrarenal abdominal aortic aneurysm

OBJECTIVE: A more accurate means of prediction of abdominal aortic aneurysm (AAA) rupture would improve the clinical and cost effectiveness of prophylactic repair. The purpose of this study was to determine whether AAA wall distensibility can be used to predict time to rupture independently of other recognized risk factors. METHODS: A prospective, six-center study of 210 patients with AAA in whom blood pressure (BP), maximum AAA diameter (Dmax), and AAA distensibility (pressure strain elastic modulus [Ep] and stiffness [beta]) were measured at 6 months with an ultrasound scan-based echo-tracking technique. A stepwise, time-dependent, Cox proportional hazards model was used to determine the effect on time to rupture of age, gender, BP, Dmax, BP, Ep, beta, and change in Dmax, Ep, and beta adjusted for time between follow-up visits. RESULTS: Median (interquartile range) AAA diameter was 48 mm (41 to 54 mm), median age was 72 years (68 to 77 years), and median follow-up period was 19 months (9 to 30 months). In the Cox model, female gender (hazards ratio [HR], 2.78; 95% CI, 1.23 to 6.28; P =.014), larger Dmax (HR, 1.36 for 10% increase in Dmax; 95% CI, 1.12 to 1.66; P =.002), higher diastolic BP (HR, 1.13 for 10% increase in BP; 95% CI, 1.13 to 1.92; P =.004), and a decrease in Ep (increase in distensibility) over time (HR, 1.38 for 10% decrease in Ep over 6 months; 95% CI, 1.08 to 1.78; P =.010) significantly reduced the time to rupture (had a shorter time to rupture). CONCLUSION: Women have a shorter time to AAA rupture. The measurement of AAA distensibility, diastolic BP, and diameter may provide a more accurate assessment of rupture risk than diameter alone.     

肾动脉狭窄血管腔内治疗的临床研究

目的评估肾动脉狭窄血管腔内治疗的安全性与疗效。方法33例肾动脉狭窄患者因严重高血压或伴有肾功能不全而进行了肾动脉经皮血管腔内成形和支架植入术（PTRAS）,随访7～49个月,平均（244-2）个月,观察手术对患者血压、肾功能及病死率的影响。结果手术技术成功率为97．0％;2例（6．1％）术后4个月内死于心肌梗死;5例（15．2％）术前血清肌酐（Scr）≥177μmol／L,术后血压、Scr无明显改善,其中4例术后17～28个月死于尿毒症;总的病死率为18．2％。术前Scr〈177μmol／L的患者,术后12、24个月,收缩压及舒张压明显下降,服用降压药物种类明显减少（P〈0．05）。结论无严重心肾疾病的患者,PTRAS能明显降低血压,稳定肾功能,减少口服降压药种类,有较好的安全性和疗效;术前Scr≥177μmol／L的患者,术后病死率高,行PTRAS要慎重。肾保护装置可能对肾功能有保护作用。     

Predictive factors and clinical consequences of proximal aortic neck dilatation in 230 patients undergoing abdominal aorta aneurysm repair with self-expandable stent-grafts

OBJECTIVE: Several studies have suggested that proximal aortic neck dilatation (AND) is a frequent event after balloon-expandable endografting. Yet few data are available on AND after repair with self-expandable stent grafts. To investigate incidence, predictive factors, and clinical consequences of AND, computed tomography (CT) scans obtained at intervals during follow-up of 230 patients who had undergone endoluminal abdominal aortic aneurysm (AAA) repair with self-expandable stents were reviewed. SUBJECTS: Between April 1997 and March 2001, 318 patients underwent endoluminal AAA repair with a self-expandable endograft at our unit. CT scans obtained at 1 and 12 months after surgery and yearly thereafter were prospectively stored in a computer imaging data base. Two hundred thirty patients were available for minimum 1-year assessment. Two vascular surgeons with tested interobserver agreement reviewed 686 CT scans. Diameter of the proximal aortic neck was measured as the minor axis of the first CT section that contained at least half of the proximal portion of the endograft. For endografts with suprarenal attachment the first scan below the lowest renal artery was considered. Diameter change of 3 mm or more between the CT scan at 1 month and subsequent evaluations was defined as AND. Nine possible independent predictors of AND were analyzed with Cox regression analysis. RESULTS: Median follow-up was 24 months (range, 12-54 months). In 2 patients, AAA ruptured during follow-up. CT scans for 65 patients (28%) showed AND. Thirteen patients with AND (5.6%) underwent repeat intervention, including positioning of the proximal cuff in 8 patients and late conversion to open repair in five patients. Of the nine variables examined with multivariate analysis, only 3, ie, presence of neck circumferential thrombus (hazard ratio [HR], 2.51; 95% confidence interval [CI], 1.26-5.01; P =.008), preoperative proximal neck diameter (HR, 1.21; 95% CI, 1.07-135; P =.001), and preoperative AAA diameter (HR, 1.03; 95% CI, 1.00-1.06; P =.046) were positive independent predictors of AND, whereas the other 6, ie, neck angulation more than 60 degrees, neck length, suprarenal fixation, oversizing more than 15%, endoleak at 30 days, and increased AAA diameter during follow-up, showed no significant correlation. Probability of AND at 48 months was 59 +/- 6.1 at analysis with the Kaplan-Meier method. CONCLUSIONS: AND is a frequent sequela of endoluminal repair in the mid-term. Severe AND developed in a small percentage of our patients, compromising integrity of AAA repair. Patients with large aneurysms and aortic necks and patients with aortic neck circumferential thrombus are at high risk for aortic neck enlargement after endoluminal repair of AAA.     

术前二十二碳六烯酸水平与肾癌患者术后预后的关系分析

目的 探究肾癌患者术前血清二十二碳六烯酸(docosahexaenoic acid, DHA)水平与术后预后的相关性.方法 选取2004年10月至2014年10月期间140例肾癌患者,分为高DHA组(n=110,患者DHA水平≥3.81%)和低DHA组(n=30,患者DHA水平<3.81%),收集患者的基本临床病理数据,测定患者术前、术后血清DHA水平,以评估相关性.结果 高DHA组患者M1期的比率显著低于低DHA组患者(P<0.05);Kaplan-Meier分析发现,高DHA组患者的癌症-特异生存率显著高于低DHA组患者(P=0.005);多变量Cox比例风险模型分析发现,恶病体质(HR=4.973,95% CI:0.136~7.851,P=0.009)、M1(HR=3.209,95% CI:1.113~4.386,P=0.023)、低DHA(HR=3.891,95% CI:0.360~8.225,P=0.021)是肾癌患者癌症-特异生存率的显著危险因素.术前DHA水平与术后DHA水平差异无统计学意义(P>0.05).结论 术前DHA水平可以作为肾癌患者术后的独立预测因子.     

Renal functional and cardiovascular outcomes of partial nephrectomy versus radical nephrectomy for renal tumors: a systematic review and meta-analysis

This systematic review and meta-analysis aimed to evaluate the postoperative renal and cardiovascular outcomes of partial nephrectomy (PN) versus radical nephrectomy (RN) for the treatment of renal carcinoma. A systematic literature search was performed on scientific databases including Scopus, Web of Science, MEDLINE, and EMBASE from their inception to September 2021. Studies comparing renal and cardiovascular outcomes between PN and RN in patients with renal cancer were included. The generic inverse variance method with random-effects models was used to determine the pooled hazard ratios and odds ratio for each outcome. Quality Assessment for observational studies was guided by the New-Castle Ottawa Scale. Overall, a total of 31 studies (n=51,866) reported renal outcomes, while 11 studies (n= 101,678) reported cardiovascular outcomes. When compared to PN, RN had a higher rate of new-onset postoperative EGFR <60 mL/min/1.73 m² (HR 3.39; CI 2.45 - 4.70; I²=93%; P=<0.00001) and EGFR <45 mL/min/1.73 m² (HR 4.70; CI 2.26 - 9.79; I²=98%; P=<0.0001). No difference was observed in new-onset advanced kidney disease and end-stage renal disease. A 19% reduction in cardiovascular events was observed in the PN group (HR 0.81; CI 0.70 - 0.93, P=0.002). No protective effect of PN was observed in new-onset or worsening hypertension (HR 0.85; CI 0.64 - 1.14, P=0.28) nor myocardial infarction (HR 0.86; CI 0.71 - 1.04, P=0.13). PN was associated with a decreased risk of postoperative early-stage CKD and cardiovascular events compared with RN. However, no benefit of PN over RN was observed in advanced CKD, new-onset or worsening hypertension, myocardial infarction, and cardiovascular mortality.     

Post-Transplant Renal Artery Stenosis: Impact of Therapy on Long-Term Kidney Function and Blood Pressure Control

Purpose

We assessed the long-term outcome of different treatment methods for transplant renal artery stenosis.

Materials and Methods

Outcome data for 23 patients with transplant renal artery stenosis treated during a 16-year period were reviewed and analyzed.

Results

There was a higher incidence of renal artery stenosis in cadaveric donor kidneys compared to living donor kidneys (2 percent versus 0.3 percent, p less than 2), and in cadaveric kidneys from pediatric donors less than 5 years old compared to those from adults (13.2 percent versus 1.3 percent, p less than 0.01). Six patients underwent primary medical treatment for renal artery stenosis, with a successful outcome in 4 (mean followup plus or minus standard error 57 plus/minus 22 months) and failure in 2. Of the patients 16 were treated with percutaneous transluminal angioplasty, including 12 who were cured or improved with respect to hypertension (followup 44.7 plus/minus 7.6 months). Five patients underwent surgical revascularization for renal artery stenosis with postoperative improvement of hypertension (followup 18.8 plus/minus 11.6 months). Overall, 21 of 23 patients (91 percent) were treated successfully for transplant renal artery stenosis with cure or improvement of associated hypertension. Posttreatment renal function was stable or improved in 18 patients, while renal function deteriorated due to parenchymal disease in 3.

Conclusions

Most patients with transplant renal artery stenosis can be treated successfully. Percutaneous transluminal angioplasty is the initial interventive treatment of choice for high grade renal artery stenosis. Surgical revascularization is indicated if percutaneous transluminal angioplasty cannot be done or is unsuccessful.     

Long-term outcome after surgical kidney revascularization for fibromuscular dysplasia and atherosclerotic renal artery stenosis

PURPOSE: At a time of minimally invasive surgery in urology, the role of surgical kidney revascularization in the management of renal artery disease has changed during the last decade. Our experience with surgical kidney revascularization, and the long-term clinical outcomes of fibromuscular dysplasia (FMD) and atherosclerotic renal artery stenosis are reviewed. MATERIALS AND METHODS: The study group comprised 140 patients with renovascular hypertension, 72 with FMD and 68 with atherosclerotic renal artery disease, who underwent surgical revascularization between 1982 and 1999. The indications for surgical revascularization were the treatment of hypertension and the preservation of renal function in 17 patients with renal artery occlusion, 55 with ostial stenosis, 52 with branch stenosis, 6 with bilateral artery stenosis, 7 with solitary kidney renal artery stenosis and 3 with solitary kidney renal artery occlusion. RESULTS: Postoperative blood pressure and renal function were monitored for 1 to 17 years (mean 11.3). Long-term blood pressure control was observed in 93% of patients with FMD and in 71% of those with atherosclerosis. Improvement or stabilization of renal function was observed in 92% of patients with FMD and in 68% of those with atherosclerosis. The preoperative estimated glomerular filtration rate compared to postoperative was significantly increased in both groups. CONCLUSIONS: Surgical kidney revascularization is effective in secondary hypertension with a high long-term efficacy in the normalization of blood pressure and in the preservation of renal function, especially in patients with a solitary or 1 functional kidney.     

Ischemic nephropathy and concomitant aortic disease: A ten-year experience

Purpose: The durability of renal preservation after surgical intervention has not been well defined, particularly in patients with associated aortic disease. A review of all patients at the Emory University Hospital with renal insufficiency (creatinine level ≥ 1.8) and concomitant atherosclerotic aortic and renovascular disease was undertaken.Methods: Fifty patients underwent both renal revascularization (71 kidneys) and the repair of aneurysmal or symptomatic aortic occlusive disease between 1982 and 1992. Hypertension was present in 96% of patients and diabetes was present in 10%. The preoperative estimated glomerular filtration rate (EGFR) was 25.18 ± 8.29 ml/min (creatinine level 3.1 ± 1.5 mg/dl). Operative management included bilateral renal artery repair ( n = 21), unilateral repair alone ( n = 17), and unilateral repair with contralateral nephrectomy ( n = 12). The relative percent change in the postoperative EGFR ( ≥ 7 days after operation) increased by at least 20% in 42% of the patients, had decreased by 20% or more in only 4%, and was otherwise categorized as unchanged in the remaining 54% of the study group.Results: The 30-day operative mortality rate was 2.0% (1 of 50). Forty-five of the surviving 49 patients (91.8%) were available for follow-up (median 49 months). During this period nine patients (18.4%) eventually required dialysis, four within 6 months of operation, and 19 patients died. Neither subgroup experienced a retrieval of renal function after operation. Five-year survival rate was 61%, and a trend was noted between the risk of death and the relative change in EGFR after operation ( p = 0.13). The likelihood of eventually requiring long-term dialysis was highest among those patients with low preoperative functional renal reserve as measured by preoperative creatinine level of 3 mg/dl or greater ( p < 0.0001), or preoperative EGFR less than 20 ml/min ( p = 0.0001). Blood pressure was cured or improved in 50% at late follow-up.Conclusions: Early improvement of renal function may be observed in nearly one half of patients subjected to combined aortic and renal revascularization. Nonetheless, renal preservation may not be sustainable in patients with compromised preoperative function. Intervention before marked functional decline remains the best option for minimizing the risk of eventual dialysis. (J VASC SURG 1994;19:135-48.)     

Chronic renal artery occlusion: Nephrectomy versus revascularization

Purpose: The surgical management of chronic atherosclerotic renal artery occlusion (RA-OCC) was studied. Methods: From January 1987 through December 1996, 397 consecutive patients were treated for atherosclerotic renal artery disease. Ninety-five hypertensive patients (mean blood pressure, 204 ± 31/106 ± 20 mm Hg; mean medications, 3.0 ± 1.1 drugs) were treated for 100 RA-OCCs. Eighty-four (88%) patients had renal dysfunction, defined by serum creatinine levels ≥1.3 mg/dL (mean serum creatinine level, 2.8 ± 2.0 mg/dL). Demographic characteristics, operative morbidity and mortality, blood pressure/renal function response, and postoperative decline in renal function were examined and compared with that of 302 patients treated for renal artery stenosis (RAS). Results: After operation, there were 5 perioperative deaths (5.2%), 2 (2.8%) after revascularization and 3 (12%) after nephrectomy (P = .11), compared with 12 (4.0%) perioperative deaths in the RAS group (P = .59). After controlling for important covariates, estimated survival and blood pressure benefits did not differ between RA-OCC patients treated by nephrectomy or revascularization (P = .13; 87% vs 92%, P = .54). Excretory renal function was considered improved in 49% of 79 RA-OCC patients with renal dysfunction, including 9 patients removed from dialysis-dependence. Among patients treated for unilateral disease, revascularization for RA-OCC was associated with significant improvement in renal function (P < .01); however, nephrectomy alone did not increase renal function significantly. Improved renal function after operation was associated with a significant and independent increase in survival (P < .01) and dialysis-free survival (P < .01) among patients treated for RA-OCC. In addition, blood pressure benefit, renal function response, and estimated survival did not differ significantly after reconstruction for RA-OCC or RAS. Conclusion: Among hypertensive patients treated for RA-OCC, equivalent beneficial blood pressure response was observed after both revascularization and nephrectomy. In patients who underwent bilateral renal artery revascularization, the change in excretory renal function attributable to repair of RA-OCC cannot be defined. In patients treated for unilateral disease, however, improvement in function was observed only after revascularization. Moreover, improved renal function demonstrated a significant and independent association with improved survival. This experience supports renal revascularization in preference to nephrectomy for RA-OCC in select hypertensive patients when a normal distal artery is demonstrated at operation. (J Vasc Surg 1999;29:140-9.)     

Simultaneous aortic replacement and renal artery revascularization: The influence of preoperative renal function on early risk and late outcome

PURPOSE: We documented the postoperative complication rate and the late results of simultaneous infrarenal aortic replacement and renal artery (RA) revascularization at the Cleveland Clinic and correlated these findings with the preoperative serum creatinine level (S(Cr)) and other baseline risk factors. METHODS: A retrospective review of hospital charts and outpatient records was supplemented with a telephone canvass and the invitation to return for a complimentary RA duplex scan, when a scan had not been done within the previous year. Data were collected for 73 consecutive patients (mean age, 69 years) who underwent aortic procedures that were combined with the repair of RA stenosis from 1989 to 1997 (mean follow-up, 44 months). The preoperative S(Cr) was 2 mg/dL or lower in 45 patients (group R1; median, 1.5 mg/dL) and was higher than 2 mg/dL in the remaining 28 patients (group R2; median, 2.6 mg/dL). RESULTS: Forty-seven of the patients in this series had aortic aneurysms, 15 patients had aortoiliac occlusive disease, and 11 patients had both types of lesions. Bilateral RA revascularization was necessary for seven patients in group R1 (15%) and for eight patients in group R2 (29%). Group R2 contained more patients with medically resistant hypertension (57%) than group R1 (29%, P = .019). Although there was no statistically significant difference between the 30-day mortality rates (group R1, 2.2%; group R2, 11%), the related in-hospital mortality rate for 15 bilateral RA revascularizations (13%) was nearly twice that of 58 unilateral revascularizations (6.9%). Patients in group R2 were at a higher risk for postoperative dialysis than those in group R1 (36% vs 6.7%, P = .008), and patients in group R2 had longer lengths of stay in the hospital (median, 14 days vs 9 days; P = .004). By means of Kaplan-Meier analysis, the 5-year survival rate was lower for patients in group R2 (53%; 95% CI, 33%-73%) than for patients in group R1 (85%; 95% CI, 74%-96%; log rank P = .005). Despite all other liabilities in group R2 patients, however, their resistant hypertension was cured or improved in 88% of cases and their S(Cr) appeared to decline with time. CONCLUSION: The early postoperative risk of simultaneous aortic/RA procedures appears to be highest in patients who have an elevated S(Cr), bilateral RA stenosis or occlusion, and a comparatively low long-term survival rate. In this particular group, the adjunctive use of endovascular techniques might conceivably reduce the magnitude of the planned surgical procedure and thus enhance the overall outcome.