Increased Incidence of Renal Cysts in Patients with Abdominal Aortic Aneurysms: A Common Pathogenesis?

We have empirically observed that patients with abdominal aortic aneurysms (AAAs) seem to have an increased incidence of renal cysts on computed tomography (CT). In order to evaluate this possible association, a retrospective cohort study was conducted comparing the incidence of renal cysts on CT scan in 100 patients with AAA to 100 patients without AAA (matched by age and gender). Univariate analysis and multiple logistic regression were performed to evaluate the association of AAAs and other risk factors with the presence of renal cysts. Of patients with AAAs, 54% had renal cysts compared to only 30% in the control group (p = 0.0006, relative risk = 2.73). The AAA group had a higher incidence of chronic obstructive pulmonary disease (COPD, 14% vs. 1%), hypertension (76.6% vs. 46.5%), coronary artery disease (38.3% vs. 12%), and hypercholesterolemia (41.5% vs. 9.1%) compared to the non-AAA group. There was a significant linear correlation between renal cysts and COPD (p = 0.011), the presence of AAA (p = 0.0005), and age (p = 0.019), whereas hypercholesterolemia (p = 0.059) and diabetes (p = 0.063) approached significance. On multivariate analysis, there were three independent predictors of renal cysts: COPD (p = 0.051), age (p = 0.01), and AAA (p = 0.028). In conclusion, there is a significantly higher incidence of renal cysts in patients with AAA compared to patients without AAA. To our knowledge, this association has not previously been reported. Future studies are needed to determine whether this correlation is the result of a commonality in the pathogenesis of AAA and renal cysts.     

Postoperative Renal Function After Elective Abdominal Aortic Aneurysm Repair Requiring Suprarenal Aortic Cross-Clamping

Purpose To examine postoperative renal function after suprarenal aortic cross-clamping performed without renal hypothermia in patients undergoing elective abdominal aortic aneurysm (AAA) surgery.Methods Between 1991 and 2000, 18 patients underwent surgery for a juxtarenal AAA, which required a suprarenal aortic cross-clamp. All AAAs were repaired with a proximal anastomosis just below the renal arteries. We divided the patients into two groups according to the duration of the renal ischemia: <45min (n = 12) and 45min (n = 6). The postoperative changes in renal function were analyzed.Results There were no hospital deaths and none of the patients needed permanent hemodialysis. The postoperative peak in the serum creatinine level after suprarenal cross-clamping for 45min was significantly higher than that after cross-clamping for <45min. The percentage changes in serum creatinine and blood urea nitrogen were correlated positively with the duration of renal ischemia, and were significantly greater in the group with renal ischemia of <45min than in the group with prolonged renal ischemia (45min).Conclusions Suprarenal aortic cross-clamp without performing renal hypothermia is safe and able to be tolerated well by the patient during elective AAA surgery, although careful attention must be paid to limiting the period of renal ischemia.     

Prevalence of unsuspected abdominal aortic aneurysms in male veterans

Abdominal aortic aneurysms (AAA) are potentially lethal arterial lesions that are best managed by elective surgical repair. However, asymptomatic AAAs may go undetected on routine physical examination or patients with such lesions may not consult a physician. To determine the prevalence of asymptomatic AAAs in a high-risk population, weretrospectively reviewed all abdominal CT scans on veterans >50 years of age that had been ordered for indications other than aneurysmal disease during a recent 10-month period. Of the 111 patients studied, 15 (13.5%) had suprarenal and/or infrarenal AAAs (one patient had both). Patients with AAAs were significantly older (p=0.0001) and were heavier tobacco users (p=0.003). For patients >60 years of age with peripheral vascular occlusive disease and a history of tobacco use, there was a 29.2% prevalence for AAA compared with 0% in those without any of these risk factors (p=0.04). There was a very definite trend suggesting that patients with peripheral vascular disease (p=0.06) were more likely to have an AAA. Because of the high prevalence of AAAs found in this population we then conducted aprospective study over a 24-month period during which patients >60 years of age with known peripheral vascular disease and a history of smoking who presented to the vascular laboratory for evaluation of problems not related to AAA were asked to undergo an abdominal CT scan. Fifty-six volunteers agreed to participate in the study. Seven patients had AAAs and one patient had an isolated iliac aneurysm, for a 14.3% overall prevalence of aneurysms. There was no difference in the incidence of risk factors in those patients with aneurysms and those without aneurysms. This represents one of the highest incidences for AAA thus far reported. If immediate repair is not performed, such patients must be followed closely for the development of symptoms or enlargement of their AAA.This study reflects the views of the authors and does not necessarily represent the view of the Department of Veterans Affairs or the United States Government.     

Outcomes after Abdominal Aortic Aneurysm Repair in Those ≥80 Years of Age: Recent Veterans Affairs Experience

n = 231) of the patients. A total of 5833 patients underwent repair of nonruptured AAA: mortality was 4.1% (228/5627) in those <80 and 8.25% (17/206) in those ≥80 years old (p < 0.009). Logistic regression analysis indicated age ≥80 was independently associated with higher mortality (odds ratio 1.834:1, 95% bounds 1.117-3.012). Octogenarian status (defined as ≥80 years of age), however, had a less important association with in-hospital death than did surgical complications of the heart or genitourinary tract, postoperative hemorrhage, septicemia, respiratory insufficiency, myocardial infarction (MI), acute renal failure, surgical complications of the central nervous system (CNS), aneurysm rupture, postoperative shock, or disseminated intravascular coagulation (DIC), in ascending order of importance. Only 5.9% (n= 25) of the 427 patients undergoing repair of ruptured AAA were ≥80 years old. In those ≥80 undergoing repair of ruptured aneurysms, mortality was 48% which did not differ from the 45% mortality in those <80 (NS). The likelihood that one would be operated for rupture was statistically greater (1.66:1) for those ≥80 years (p < 0.025). Length of stay (LOS) for those ≥80 undergoing AAA repair was longer being 22.3 ± 14.8 days versus 18.3 ± 13.2 days for younger patients (p < 0.001). Mortality and LOS after AAA repair were statistically greater for those ≥80 years of age. Severity of illness, however, was also greater for octogenarians. Patient Management Category (PMC) software defined illness severity was 4.06 ± 1.22 in octogenarians versus 3.84 ± 1.13 for those younger (p < 0.005). Though age ≥80 was independently associated with increased mortality, selected elderly patients could benefit from AAA repair.     

Renal stenting for incidentally discovered renal artery stenosis: is there any outcome benefit?

We evaluated whether there was a clinical outcome benefit in patients incidentally discovered to have high-grade renal artery stenosis (RAS) and treated with percutaneous transluminal renal angioplasty and stenting (PTRAS) at the time of angiogram for another indicated procedure. A retrospective chart review was performed on all patients undergoing renal arteriography over 4 years at our academic tertiary-care referral center. Review of catheterization reports was used to identify patients diagnosed with high-grade RAS (reduction of > or =70% luminal diameter by arteriogram). Patients treated with PTRAS were identified. Baseline and postprocedure blood pressure (BP, an average of at least three independent measurements), glomerular filtration rate, serum creatinine, and antihypertensive medication regimen were compared for 12 months of follow-up. Over 4 years, 124 patients underwent renal arteriography and 78 (63%) were diagnosed with high-grade RAS. Fifty-eight patients (74% of those with high-grade RAS) received PTRAS. Patients treated with PTRAS had similar baseline characteristics to those with high-grade RAS with no intervention, with the exception of lower diastolic BP (DBP; 74 +/- 11.2 vs. 80 +/- 14.2 mm Hg, p = 0.04) and a higher proportion of hyperlipidemia (78 vs. 55%, p = 0.05). Thirty-eight out of 58 PTRAS patients (66%) received sufficient follow-up to assess outcomes. When baseline and postprocedure variables were compared in PTRAS patients with 12-month follow-up, there was a reduction in systolic BP (SBP, 153 +/- 20.8 vs. 136 +/- 27.2 mm Hg, p = 0.01) and mean arterial pressure (MAP, 103 +/- 11.2 vs. 95 +/- 14 mm Hg, p = 0.04). When these patients were stratified by those with an increase, decrease, or no change in postprocedure antihypertensive medications, significant reductions in SBP, MAP, and DBP were noted only in the patient population that also had an increase in the number of antihypertensive medications. No differences in renal insufficiency were detected. Patients with high-grade RAS incidentally discovered during arteriography performed for extrarenal disease and treated with PTRAS have a modest reduction in BP, which is significant only in those patients with an increased number of antihypertensive medications postprocedure. Caution must be taken in stenting patients with incidental RAS as outcome benefit may be minimal when compared to medical management only.     

Morphology predicts rapid growth of small abdominal aortic aneurysms

This study evaluated CT scans of small abdominal aortic aneurysms (AAAs) (< 5 cm) to assess anatomic features associated with rapid expansion. Serial CT scans obtained at least 10 months apart (mean 15 months) from patients with small AAAs were reviewed. Each cross-sectional image of the AAAs was analyzed using a computer-assisted design program. The circumference of the AAA in each CT image was divided into eight equal arcs, from which the apparent radius of curvature (Rc) for each segment was calculated. Flattening of the wall curvature results in an increased segmental Rc. The CT scans of nine patients with expanding AAAs (expansion 0.5 cm/yr) were compared to those of 10 patients with stable AAAs (expansion <0.2 cm/yr). To adjust for differences in AAA size, the Rc for each segment was normalized by dividing each individual Rc by the average of the eight Res (RcAvg) calculated for that cross-sectional CT image. Analysis of variance showed that the left posterolateral segments in expanding AAAs had larger Rc/RcAvg ratios than those segments in stable AAAs (1.14 ± 0.19 vs. 0.80 ± 0.09, p < 0.02). Laplace's law indicates that the left posterolateral segment in AAAs that grow more rapidly is subjected to greater wall tension. Flattening in the curvature of the left posterolateral wall segment was significantly associated with an increased rate of expansion in small AAAs. This finding, readily derived from standard CT scan images, may predict which small AAAs are more prone to rapid expansion.Presented at the Eighteenth Annual Meeting of the Peripheral Vascular Surgery Society, Washington, D.C., June 6, 1993.     

Thoracoabdominal Aortic Aneurysm Repair in Patients with Single Kidney

p < 0.05. However, there was a significantly higher incidence of hypertension (97% versus 78%), coronary artery disease (50% versus 34%), and renal artery stenosis ipsilateral to functioning kidneys (88% versus 26%) in the single-kidney group than in the reference group; p < 0.05. Preoperatively, renal insufficiency (serum creatinine ≥ 2.5 mg/dl or patients on dialysis) was present in four patients (13%) in the single-kidney group and in 21 patients (4%) in the reference group; p < 0.05. In the former group, the unilateral loss of kidney function was secondary to atrophy in 30 patients (94%) and agenesis in two patients (6%). The simple clamp-open distal anastomosis technique was employed in the majority of the cases in the single-kidney group (91%) and in the reference group (83%); p > 0.05. Renal artery endarterectomy or bypass ipsilateral to functioning kidneys was performed on 18 patients (56%) in the single-kidney group and 68 patients (12%) in the reference group; p < 0.05. Renal perfusion with cold Ringer's lactate solution was done in 18 cases (56%) in the single-kidney group and 228 cases (42%) in the reference group; p > 0.05. There was no difference in the operative mortality (9% versus 7%) and the incidence of paraplegia/paraparesis (6% versus 5%) between the single-kidney group and the reference group; p > 0.05. Postoperatively, new onset renal insufficiency developed in 10 patients (31%) in the single-kidney group, and 58 patients (11%) in the reference group; p < 0.05. In the single-kidney group, four patients (13%) had mild renal dysfunction (serum creatinine ≥ 2.5 mg/dl), and two patients (6%) were on dialysis on discharge. Notably, there was no significant difference in the incidence of renal insufficiency on admission compared to the incidence of renal insufficiency on discharge in the single-kidney group (13% versus 19%; p > 0.05). TAAA repair in patients with one functioning kidney can be performed safely. Postoperative renal insufficiency can be managed successfully in the majority of patients.     

Renin-angiotensin blockade is associated with increased mortality after vascular surgery

Purpose

The outcome of patients with preoperative renin-angiotensin system (RAS) blockade, achieved either by angiotensin converting enzyme inhibitors or angiotensin receptor blocking agents, was assessed using 30-day mortality as a primary end point.

Methods

An observational cohort study of 883 consecutive patients undergoing elective open abdominal aortic aneurysm repair (AAA) was undertaken and analyzed using a propensity score matched study. The data collected included medical history, anesthetic techniques, and postoperative outcomes. Logistic regression analysis identified predictors of RAS blockade: hypertension, stroke, congestive heart failure, diabetes, and heart disease. A propensity score for RAS blockade was calculated for each subject using several factors: age, sex, serum creatinine, hypertension, heart disease, congestive heart failure, stroke, diabetes, and exposure to cardiovascular medications. Subjects and controls were matched using the calculated propensity score.

Results

The overall 30-day mortality rate was 3.5% (31/883 patients). The crude mortality rate in RAS blocked patients was 5.8% (21/359) vs 1.9% (10/524) in unexposed patients (odds ratio 3.2, with 95% confidence intervals [CI₉₅] 1.5-6.7; P < 0.001). Analysis of 261 propensity score matched pairs showed a 30-day mortality rate of 6.1% (16/261) in the RAS blocked group vs 1.5% (4/261) in unblocked patients (P = 0.008). The estimated odds ratio for 30-day mortality associated with RAS blockade was 5.0 (CI₉₅ 1.4-27).

Conclusions

Examination of 883 cases of AAA repair showed increased mortality associated with preoperative RAS blockade. A better understanding of perioperative pharmacology and physiology of RAS blockade is needed as well as future studies to identify causality.     

Infrarenal Abdominal Aortic Aneurysm Repair via Endovascular Versus Open Retroperitoneal Approach

The beneficial effects of open surgical abdominal aortic aneurysm (AAA) repair via a left retroperitoneal approach have been established. We compared the short-term outcome of infrarenal AAA repair via an endovascular approach with that of an open retroperitoneal approach. From October 2001 to April 2003, patients with infrarenal AAA >5 cm were offered repair via an endovascular approach (group I) with a variety of industry-made stent grafts or with an open retroperitoneal surgical approach (group II). Data were prospectively collected in the vascular registry and complications were analyzed. Data comparison between the two groups was done by using chi-squared analysis and two-tailed Students t-test. Statistical significance was identified at p < 0.05. Over an 18-month period, 492 patients underwent evaluation for AAA. Of these, 446 patients had infrarenal AAA and underwent either endovascular (group I: n=175, male 85%, female 15%) or open surgical repair (group II: n=232, male 74%, female 26%) via a left retroperitoneal approach. Group I patients had a higher incidence of coronary artery disease (66% vs. 35%, p < 0.05), hypertension (74% vs. 43%, p < 0.05), chronic obstructed pulmonary disease (29% vs. 12%, p < 0.05), and diabetes mellitus (20% vs. 7%, p < 0.05), a lower mean amount of intraoperative blood loss (277 cc vs. 1452 cc, p < 0.05), and shorter length of stay in the hospital (1.7 days vs., 7.3 days, p < 0.05). Group I also had fewer complications of myocardial infarction (1.7% vs. 5.2%, p=NS), renal failure (0% vs. 2.6%, p < 0.05), pulmonary failure (1.7% vs. 2.6%, p=NS), ischemic colitis requiring colectomy (0.6% vs. 2.6%, p < 0.05), multisystem organ failure (0% vs. 1.3%, p=NS), and death (0.6% vs. 1.3%, p < 0.05). Despite increased preexisting comorbidities, patients undergoing endovascular aneurysm repair had less morbidity, mortality, and blood loss and a shorter in-hospital length of stay than patients undergoing open surgical aneurysm repair via a left retroperitoneal approach.Presented at the 28th Annual Meeting of the Peripheral Vascular Surgery Society, Chicago, IL, June 7, 2003.     

Predictors of Early Discharge following Open Abdominal Aortic Aneurysm Repair

Patients undergoing endovascular abdominal aortic aneurysm (AAA) repair have lower perioperative morbidity and leave the hospital earlier than patients undergoing open repair. However, potential complications require continuous surveillance of endografts and there are few data regarding their long-term fate. If an open operation were well tolerated, this might be a preferable alternative. The purpose of this study was to identify patients with lower morbidity and shorter hospital stay following open AAA repair and to analyze factors that might point to open repair as the preferred approach. We performed a retrospective review of all patients who underwent AAA repair between 1995 and 2000 at our institution. All patients with ruptured aneurysms and those that required renal, celiac, or superior mesenteric reconstructions during the AAA repair were excluded. Patient demographics, preoperative comorbid conditions, intraoperative data, and postoperative complications were analyzed in detail. A total of 115 patients fulfilled the inclusion criteria. There was only one perioperative death (0.9%). The mean hospital stay was 8.1 days. A history of chronic obstructive pulmonary disease (COPD) and longer operative time were independent factors associated with prolonged hospital stay. Forty-one patients (35.6%) left the hospital in 5 or less days. Compared to the group with hospital stay >5 days, these patients had a lower incidence of COPD (7.3% vs. 25.7%, p < 0.05) and smaller-size AAAs (5.6 vs. 6.4 cm, p < 0.0001), and were more often operated on via a retroperitoneal approach (61% vs. 40.5%, p < 0.05). Their time in the operating room was less (3.5 vs. 4.5 hr, p < 0.0001), and they had less estimated blood loss (750 vs. 1500 cc, p < 0.001) and fewer transfusions (0.95 vs. 2.45 units, p < 0.0001). Patients without COPD and smaller AAAs that can be repaired via a retroperitoneal approach have a lower incidence of perioperative complications and a shorter hospital stay following open AAA repair. Until long-term results for endografts are available, our data suggest that these patients are well served with an open repair.     

Ruptured abdominal aortic aneurysm: Impact of comorbidity and postoperative complications on outcome

Ruptured abdominal aortic aneurysm (AAA) remains a common and highly lethal problem. This study evaluates the morbidity and mortality rates and aims to identify which clinical variables could predict the outcome. We reviewed the records of 112 patients (97 men and 15 women) operated on for ruptured infrarenal AAA within the past 12 years (April 1, 1980, to March 31, 1992). Forty-seven clinical variables were collected and correlated with outcome by univariate and multivariate analysis. Mean age was 72.4 years (range 51 to 89 years). Only 12.5% were known to have an AAA before rupture. Preoperative systolic pressure <90 mm Hg was present in 84 patients (75%) and 11 patients (9.8%) experienced cardiac arrest before surgery. The in-hospital mortality rate was 49.1% (55/112). Two preoperative variables were associated with increased mortality: systolic pressure <90 mm Hg and cardiac arrest (p = 0.04 andp= 0.009, respectively). Preoperative comorbidity had no impact on outcome. Massive blood loss (5000 ml) was an intraoperative factor predictive of increased mortality (p = 0.0007). After multivariate analysis, only the following five postoperative variables were associated with increased mortality: cardiac event, renal failure requiring dialysis, coagulopathy, bleeding, and multisystem organ failure (allp <0.05). We did not identify a preoperative factor that predicts certain death and allows us to deny a patient a chance at survival. The occurrence of multisystem organ failure is associated with no survivors and raises the ethical issue of withholding treatment for these patients in the postoperative course. We favor selective screening and aggressive elective repair to improve survival by operating before rupture occurs.Presented at the Fifteenth Annual Meeting of the Canadian Society for Vascular Surgery, Vancouver, B.C., September 10–12, 1993, and at the Fourth Annual Winter Meeting of the Peripheral Vascular Surgery Society, Breckenridge, Colo., January 21–23, 1994.     

Inflammatory abdominal aortic aneurysms: A case-control study

Purpose: This study was designed to identify significant differences in the clinical and radiologic characteristics and outcome between patients with inflammatory and noninflammatory abdominal aortic aneurysms (AAAs).Methods: We reviewed 29 consecutive patients who underwent repair of an inflammatory AAA between 1985 and 1994. This group was matched in a case-control fashion by date of surgery and by the performing surgeon to a group of 58 patients who underwent repair of noninflammatory AAAs.Results: The two groups had comparable characteristics of age, gender, and cardiovascular risk factors. Patients with inflammatory AAAs were significantly more symptomatic than those with noninflammatory AAAs (93% vs 9%, p < 0.001), were more likely to have a family history of aneurysms (17% vs 1.5%, p = 0.007), and tended to be current smokers (45% vs 24%, p = 0.049). Thi most significant laboratory difference was an elevated sedimentation rate in patients with inflammatory AAAs (mean, 53 mm/hr vs 12 mm/hr, p < 0.00001). Inflammatory AAAs also were significantly larger than noninflammatory AAAs at presentation (6.8 cm vs 5.9 cm, p < 0.05). Although operative mortality was low in both groups, patients with an inflammatory AAA tended to have higher morbidity, including sepsis ( p < 0.01) and renal failure ( p = 0.04). Five-year survival rates, however, were similar for the two groups (79% for inflammatory and 83% for noninflammatory AAAs). On follow-up computed tomographic scans, the retroperitoneal inflammatory process resolved completely in 53% of the patients, but 47% of patients had persistent inflammation that involved the ureters in 32% and resulted in long-term solitary or bilateral renal atrophy in 47%.Conclusions: This case-control study provides preliminary evidence that inflammatory AAAs may have a relatively strong familial connection and that current smoking may play an important role in the inflammatory response. The study also documents that persistent retroperitoneal inflammation may be more prevalent than has been previously reported, and stresses the need for an improved understanding of the pathogenesis and long-term management of inflammatory AAAs. (J Vasc Surg 1996;23:860-9.)     

Adjunctive renal artery revascularization during juxtarenal and suprarenal abdominal aortic aneurysm repairs

Background

We report a 15-year experience with renal artery revascularization during abdominal aortic aneurysm (AAA) repair.

Methods

AAA repairs from 1994 to 2009 were reviewed. Postoperative complications, renal function, patency, and survival in patients undergoing renal artery revascularization were evaluated and compared with a control group of patients undergoing juxtarenal AAA repairs not requiring renal artery revascularization.

Results

Sixty patients underwent renal artery revascularization during AAA repair. Transient postoperative renal insufficiency occurred in 20 patients. Temporary hemodialysis was required in 3 patients, with none requiring permanent hemodialysis. There was 1 postoperative death. There was 1 renal artery revascularization failure at 1 month but no other graft failures at 12 months median follow-up evaluation (1-year patency, 97%). In comparison with the control group, transient renal insufficiency and pulmonary complications (33.3% vs 19.8%; P = .042) were more common with renal artery revascularization, with no differences in long-term renal complications or mortality.

Conclusions

Renal artery revascularization can be performed during AAA repair with excellent patency and minimal morbidity.     

Carbon dioxide digital subtraction arteriography: a pilot study

To investigate the diagnostic value of carbon dioxide arteriograms in patients with peripheral vascular disease, ten patients in whom standard contrast arteriography was contraindicated underwent carbon dioxide digital subtraction arteriography. Lower extremity ischemia or severe hypertension with renal insufficiency were the indications for arteriography. Standard contrast arteriography was precluded by chronic nondialysis-dependent renal insufficiency, severe congestive heart failure or contrast hypersensitivity. All critical arterial segments were well visualized with the exception of the infrapopliteal arterial tree in three patients. Adequate imaging of this segment required the addition of 20 cc of dilute nonionic contrast. Guided by carbon dioxide digital subtraction arteriography, four percutaneous transluminal angioplasties and three reconstructive procedures were successfully performed. One patient did not have surgically reconstructible disease and two had renal arteries without critical stenoses. Renal function transiently deteriorated in one patient who received 20 cc of nonionic contrast. No adverse events occurred due to carbon dioxide. Clinically useful diagnostic arteriograms are possible using carbon dioxide as the contrast agent.     

Value of Doppler ultrasound for the diagnosis of renal artery stenosis in children

To evaluate the reliability of Doppler ultrasonography (US) in identifying children with renal artery stenosis (RAS) among those with hypertension, we compared Doppler US results in 22 hypertensive children (mean age 8.9±4.3 years), with (13 cases) and without RAS at angiography, and in 33 normotensive children (mean age 8.8±4.7 years). We observed 2 false-negatives and 2 false-positives with Doppler US. Of the 2 false-negative diagnoses, 1 had RAS on an accessory renal artery located behind a normal upper polar artery and the other was observed in a patient with bilateral multiple stenosis of the very distal segments of renal arteries. The 2 false-positive diagnoses were due to sinuous left renal artery and to technical reasons, respectively. In another patient, Doppler US showed a tight RAS, while arteriography was normal. RAS was subsequently confirmed by a second arteriography. Peak systolic velocity values of Doppler US were significantly higher in patients with proven angiographic RAS (3.44±0.66 m/s) than in hypertensive patients with normal renal arteries at angiography (0.99±0.35 m/s, P <0.0001) and normotensive healthy children (1.04±0.23 m/s, P <0.0001). With the use of multiple views, and the experience acquired with practice, false-negatives or false-positives due to the geometry of the renal artery can be avoided. Nevertheless, very distal stenosis can be missed by Doppler US. Received October 30, 1995; received in revised form April 16, 1996; accepted May 14, 1996     

Prevalence of ischemic nephropathy in patients with renal insufficiency.

To estimate its clinically unsuspected prevalence among patients with renal insufficiency, renal duplex sonography (RDS) was used to estimate the presence of critical renal artery stenosis (RAS) in that population. Patients, aged 45 to 75 years, with a serum creatinine of greater than or equal to 2.0 mg% but without dialysis dependence, prior renal transplantation, or prior renal artery surgery were considered for RDS. Fifty-three patients who met criteria for study were randomly selected from the Section of Nephrology clinic files and each patient was contacted both by mail and by telephone. Twenty-five patients agreed to RDS, and renal artery anatomy was determined in 21 patients using standardized RDS techniques. These techniques have demonstrated an overall accuracy of 96 and 97 per cent when compared prospectively to conventional angiography during validity analyses in the authors' center. Results of RDS revealed significant findings in 5 of 21 patients (24%). Three patients demonstrated criteria for ischemic nephropathy (IN): one patient had RAS with contralateral renal artery occlusion confirmed by angiography, while 2 patients demonstrated unilateral RAS. An abdominal aortic aneurysm and unilateral hydronephrosis were discovered in the fourth and fifth patients. Evaluation of patient demographic data and functional parameters as predictors of IN revealed that the duration of renal insufficiency at the time of RDS and extra-renal organ-specific atherosclerotic damage were significantly different between the groups with and without IN. The authors preliminary findings suggest that unsuspected ischemic nephropathy may exist in a significant minority of patients with renal insufficiency.     

Endovascular AAA repair in patients with renal insufficiency: strategies for reducing adverse renal events

Vascular imaging, usually employing nephrotoxic contrast agents is relied upon for all aspects of endovascular AAA repair causing some to consider renal insufficiency a relative contraindication. We sought to determine if endovascular AAA evaluation and repair could be successfully accomplished by minimally or non-nephrotoxic modalities.Records and results for 98 consecutive patients undergoing endovascular AAA repair were reviewed. Patients requiring dialysis preoperatively were excluded (N=3).The average volume of iodinated contrast agent employed for intraoperative imaging was 152 cc (35-420 cc). Twenty patients (20%) had baseline renal insufficiency (serum creatinine > or =1.3 mg/dl). A rise in serum creatinine above baseline was observed in 23 (24%) patients following repair; for 15 (16%) this was permanent. Creatinine rise occurred in patients with both normal (15) and abnormal (8) baseline values (P=0.09). Rise in creatinine was independent of contrast volume employed and of the use of infrarenal vs suprarenal device fixation (P>0.05). Two (2%) patients required permanent dialysis, one of which had a normal baseline creatinine and unclear etiology for renal failure, the other had a baseline creatinine of 2 and required device placement over an accessory renal artery. Strategies to minimize the use of nephrotoxic contrast for patients with renal insufficiency included the use of MRA, rather than contrast-CT for pre and postoperative imaging (7, 35%) and use of Gadolinium rather than iodinated contrast for performance of intraoperative arteriography (5, 25%). Endovascular grafts were successfully designed and implanted based upon MRA as the sole preoperative imaging modality in every case in which it was attempted (7). Mortality was not significantly different between those with and without abnormal baseline renal function (P>0.05). Adverse events (access failures, arterial injuries, blood loss, endoleaks) were not significantly correlated with baseline renal insufficiency, rise in creatinine from baseline, use of MRA or intraoperative Gadolinium angiography (P>0.05).Pre- and postoperative evaluation and performance of endovascular AAA repair can be accomplished in patients with renal insufficiency without increasing the rate of mortality or adverse events employing a strategy which minimizes the use of nephrotoxic contrast agents, relying upon Gadolinium arteriography and MRA. Endovascular grafts can be successfully planned and followed employing MRA as the sole imaging modality.     

Abdominal aortic aneurysm screening program in Poland

Background

Screening for abdominal aortic aneurysms (AAA) is currently recommended by several vascular societies. In countries where it has been introduced the prevalence of AAAs differed greatly and was mainly related to cigarette smoking. The screening program also had an enormous impact on the decrease of AAA ruptures and reduced mortality rate. These facts have led to the introduction of the first screening program for AAAs in Poland.

Objective

The aim of the study was to determine the prevalence of AAAs among men aged 60 years and older undergoing ultrasound examination of the abdominal aorta.

Material and methods

A single ultrasonography of the abdomen was performed to assess the aorta from the renal arteries to the bifurcation and the diameter of the aorta was measured at its widest point. The cut-off value for determining an aortic aneurysm was set at a diameter of ≥?30 mm. All ultrasonography measurements were performed by physicians in outpatient departments throughout the Kuyavian-Pomeranian Province. Additionally, each subject had to fill out a questionnaire with demographic data, smoking habits, existing comorbidities and familial occurrence of AAAs. The study was conducted from October 2009 to November 2011.

Results

The abdominal aorta ultrasound examinations were carried out in 1556 men aged 60 years and older. The prevalence of AAA in the study population was 6.0?% (94 out of 1556). The average age of the men was 69 years (SD 6 years, range 60–92 years). In the study population 55?% of the men smoked or had smoked and 3?% were aware of the presence of AAAs in family members. There were three risk factors significantly associated with the presence of AAAs: age (p?Conclusion The prevalence of AAAs among men in Poland is higher than in other European countries and the USA. The screening program for AAAs is an easy and reliable method for detecting early stages of the disease and risk factors which are the driving forces for the development of AAAs.     

Abdominal aortic aneurysm: the role of clinical examination and opportunistic detection.

OBJECTIVES: to investigate the method of discovery of abdominal aortic aneurysms (AAA) in a district general hospital setting. Design: retrospective study. MATERIALS AND METHODS: we analysed 198 patients with an AAA who presented to our unit over a 3-year period. The method of initial diagnosis, size of the AAA and whether this was palpable, irrespective of the method of detection, were recorded. RESULTS: ninety-five (48%) were discovered clinically, 74 (37.4%) during a radiological investigation, and 29 (14.6%) at laparotomy. Of the 74 AAAs first detected radiologically, subsequent physical examination showed that 28 (37.8%) were in fact palpable and missed at presentation. The average size of those discovered clinically (6. 48+/-1.32 cm) was larger than those found radiologically (5.37+/-1. 44 cm, p<0.001) or at operation (5.43+/-1.48 cm, p=0.039). The average diameter of the palpable AAAs was also greater than that of the non-palpable AAAs (6.42+/-1.24 cm vs. 4.86+/-1.38 cm, p<0.001). CONCLUSIONS: opportunistic detection of a clinically unsuspected aneurysm during clinical examination or investigation for another reason is the most common way the diagnosis of an AAA is made. Almost half of the aneurysms were diagnosed clinically, but physical examination also missed more than a third of those detected radiologically. Despite technological advancement, clinical examination still plays a paramount role in the detection of AAAs. Larger AAAs are usually palpable and more likely to be detected on clinical examination.     

Outcome of concomitant renal artery reconstructions in patients with aortic aneurysm and occlusive disease

The question remains as to whether patients presenting with aortoiliac occlusive disease (AIOD) or abdominal aortic aneurysms (AAAs) have similar outcomes when concomitant renal artery reconstructions are performed. In this study, we analyzed our experience with simultaneous aortic and renal reconstructions using a retroperitoneal approach. Over a 5-year period, all patients with either AAAs > 5 cm or symptomatic AIOD who were found to have high-grade renal artery stenosis and who underwent aortic reconstructions with concomitant renal revascularization were analyzed through our vascular surgery registry. Morbidity and mortality were quantitatively evaluated. Data were analyzed using the chi-square test. A total of 1,133 patients with AAA (n = 832) and AIOD (n = 301) underwent aortic reconstructions. Two hundred thirty-one patients had 283 concomitant renal revascularizations, including bypass, reimplantation, and endarterectomy, for high-grade (> 70%) renal artery stenosis via a left retroperitoneal approach. The mortality rate of AAA repair with and without renal revascularization was 2.3% (4/178) and 1.5% (10/654), respectively, and that of aortobifemoral bypass for AIOD with and without renal revascularization was 5.7% (3/53) and 2.8% (7/248), respectively. Of the 7 deaths in patients requiring aortic and renal reconstructions, 4 occurred in patients with bilateral renal revascularization. Transient renal insufficiency, ischemic colitis, and cardiopulmonary failure occurred in 5.6%, 2.2%, and 9.6% of patients with AAA repair and in 5.7%, 0%, and 9.4% of patients with AIOD. Two patients developed acute occlusion of their renal bypasses; one was successfully revised, whereas the other led to a nephrectomy. In patients with AAAs, AIOD, and high-grade renal artery stenosis, simultaneous aortic and renal reconstructions can be performed through a retroperitoneal approach with a limited and acceptable mortality. With concomitant renal and aortic procedures, patients with AIOD have a higher mortality when compared with those with AAAs, although this difference is not statistically significant.