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Background A new synthetic cyclic adenosine monophosphate phosphodiesterase inhibitor, cilostazol, has been shown to inhibit platelet aggregation and act synergistically with endogenous prostaglandin I2 to enhance smooth-muscle cell vasodilitation. The effect of cilostazol in ischemia/reperfusion injury-induced compartment syndrome was investigated. Methods Sixteen rabbits underwent femoral artery occlusion after ligation of branches from the terminal aorta to the femoral artery. After 7 hours of ischemia, reperfusion was established with heparinized polyethylene shunts. Experimental animals (n = 8) received cilostazol (3.0 mg/kg) and control animals (n = 8) received normal saline as an intravenous infusion 10 minutes before shunt placement. During reperfusion, anterior compartment pressure was continuously monitored in the left lower extremity, and femoral artery blood flow was measured by laser Doppler fluorometry. To quantitate skeletal muscle oxidative metabolism and viability, triphenyltetrazolium chloride (TTC) reduction (micrograms of TTC per milligram of protein) of tibialis anterior muscle from the right lower extremity was measured at femoral artery occlusion, 7 hours of ischemia, and 2 hours of reperfusion. To assess tissue edema, dry/wet weight ratios were also determined at these intervals. Data were expressed as means +/- SE. Comparisons within groups were performed by analysis of variance, and comparisons between groups with two-tailed unpaired t tests. Results At 2 hours of reperfusion, the difference between controls and cilostazol-treated animals was extremely significant (p = 0.0008). Preischemia and 2-hour reperfusion TTC and dry/wet weight ratios were not significantly different within or between experimental groups, nor was femoral artery blood flow during reperfusion. Conclusion Cilostazol inhibits the increase in compartment pressure central to the development of the compartment syndrome. The mechanism appears to be independent of altered tissue permeability or oxidative metabolism.

Purpose: Primary radiocephalic arteriovenous fistulas (RCAVFs) have classically been used for the initiation of dialysis. If a suitable forearm cephalic vein can be demonstrated, it is used to construct such a fistula. However, we have noted a tendency for RCAVF in patients with a history of diabetes mellitus (type I and type II) to remain patent but not mature to the point of cannulation. Therefore, the present study was undertaken. Methods: Fifty-eight consecutive patients with diabetes who required initial access for hemodialysis at an urban medical center and tertiary Veterans Medical Center underwent creation of an RCAVF (n = 10), brachiocephalic arteriovenous fistula (BCAVF; n = 22), or transposed basilic vein arteriovenous fistula (TBAVF; n = 26). The vein used was determined by physical examination with tourniquet compression. If neither forearm or upper-arm cephalic veins were 2 mm in diameter, a TBAVF was created after venography. Patency was determined by Kaplan-Meier estimate; differences between groups were assessed by Fisher's exact test. Results: The 70% rate of nonmaturation of RCAVFs was significantly greater than the 27% rate for BCAVFs and 0% for TBAVFs (p < 0.05). The 33% cumulative primary patency rate at 18 months for RCAVFs was significantly less than 78% for BCAVFs and 79% for TBAVFs (p < 0.001). Within and between groups, there were no significant differences in age, gender, aspirin use, history of congestive heart failure, erythropoietin use, hematocrit level, history of peripheral vascular disease, or mortality rate. Conclusions: In patients with renal failure and a history of diabetes, both primary BCAVFs and TBAVFs demonstrate significantly greater maturation and increased primary cumulative patency rates compared with RCAVFs; therefore, these autogenous conduits are considered to be optimal in this group of patients. Whether the discrepancy in lower-arm vein maturation is a result of a lack of compensatory increase in radial arterial flow or an intrinsic defect in the lower-arm cephalic vein is currently under investigation. (J Vasc Surg 1998;27:154-7.)

Objective: To examine whether the symptom class of qualifying events predicts subsequent outcomes in a large randomized clinical trial (RCT) of carotid artery stenting compared to carotid endarterectomy. Background The importance of stroke, TIA, amaurosis fugax, and asymptomatic status has not been analyzed together and comparatively as predictors of outcome following revascularization for carotid stenosis in a large RCT. Design/Methods: Qualifying events of the 1321 symptomatic patients in the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) were modeled as predictors of the primary outcome (stroke, myocardial infarction, and death during a 30-day peri-procedural period, or ipsilateral stroke over the follow-up period out to 4 years) and as predictors of stroke and death. The model included other predictors such as age, sex, and treatment. Results: The qualifying events among the symptomatic patients were 572 strokes, 550 TIA, and 199 amaurosis fugax. Relative to symptomatic patients qualifying with stroke, the risk of subsequent primary endpoint was 15% lower for those qualifying with TIA (HR=0.85; 95% CI = 0.57 – 1.28), 36% lower for those qualifying with amaurosis fugax (HR=0.64; 95% CI = 0.3 – 1.23), and 48% lower for asymptomatic patients (HR=0.52; 95% CI = 0.35 – 0.76);the risk of stroke or death was 11% lower for TIA (HR=0.89; 95% CI = 0.57 – 1.40), 18% lower for amaurosis fugax (HR=0.82; 95% CI = 0.42 – 1.60), and 57% lower for asymptomatic patients (HR=0.43; 95% CI = 0.28 – 0.67). Conclusions: Outcomes in patients with carotid disease were predicted in descending order by stroke, TIA, amaurosis fugax, and asymptomatic status in a large RCT. Asymptomatic status and amaurosis fugax have a comparatively benign prognosis. Better understanding of these predictors may help in determining who will benefit from carotid revascularization and how quickly they may benefit given the perioperative risks. Supported by: The National Institute of Neurological Disorders and Stroke (NINDS) and the NIH (R01 NS038384); and by supplemental funding from Abbott Vascular (formerly Guidant). Disclosure: Dr. O9Mara has nothing to disclose. Dr. Hakaim has nothing to disclose. Dr. Spetzler has nothing to disclose. Dr. Bulas has nothing to disclose. Dr. Nazzal has nothing to disclose. Dr. Longbottom has nothing to disclose. Dr. Voeks has nothing to disclose. Dr. Brott has received personal compensation for activities with 3D Communications.

Purpose: The purpose of this study was to determine the indications and the long-term results for femorofemoral revascularization with autogenous vein grafts (AVG) rather than conventional synthetic materials. Methods: A consecutive series of 13 men and 12 women (mean age 64 years) receiving femorofemoral AVG was collected during a retrospective review of our experience from 1979 to 1992. Sixteen of these 25 patients required revascularization for acute ischemia in the presence of potential groin contamination (group 1), and the remaining nine had frank infections involving previous synthetic grafts (group 2). New grafts were constructed with the greater saphenous vein in 23 patients (92%) and with the cephalic vein in two. Results: One patient in each group (8%) died after operation with patent grafts. Preoperative and postoperative ankle/brachial indexes (ABI) were available for 12 patients in group 1 and for seven patients in group 2. There was significant improvement in the ABI among 11 patients with ischemia in group 1 (mean 0.33 ± 0.13; p = 0.0001), whereas no change in the ABI occurred in conjunction with the replacement of patent infected grafts among six patients in group 2 (mean 0.04 ± 0.17; p = NS). One patient from each group sustained a reduction in postoperative ABI for the recipient limb despite a patent AVG. Cumulative 3-year survival and primary patency estimates for all 23 operative survivors were 63% and 75%, respectively. Late results seemed to be comparable in group 1 and group 2, but each contained too few patients for adequate analysis. Conclusions: Despite their infrequent use, AVG seem to represent a reasonable alternative to synthetic bypass for femorofemoral revascularization in patients having either contaminated wounds or established graft infections. (J V ASC S URG 1994;19:912-5.)

In general, inferior vena caval filters are associated with low morbidity and mortality. Rarely, penetration of the inferior vena cava can occur, causing injury to adjacent structures. To our knowledge we report the first case of inferior vena caval filter penetration causing symptomatic hydronephrosis. CASE REPORT

BACKGROUND Parathyroid carcinoma is rare, with a reported prevalence of 0.6% to 4.0% in patients presumed to have primary hyperparathyroidism. This study examines the long-term results of surgical therapy and combination chemotherapy. PATIENTS From 1938 to 1988, 1260 operations for primary hyperparathyroidism were performed; only six patients (0.47%) were subsequently found to have parathyroid carcinoma. A seventh patient was referred to our institution after the diagnosis of parathyroid carcinoma had been made. RESULTS All patients had excessive hypercalcemia (serum calcium concentration > 12.0 mg/dL) with a range of 12.3 to 18.3 mg/dL. Locally recurrent tumors causing recurrent hypercalcemia were managed by repeated neck exploration and tumor resection. Six of the seven patients (85%) survived 5 years, while four patients (57%) survived 10 years. CONCLUSIONS Diagnosis of parathyroid carcinoma rests upon postoperative surveillance of patients who have undergone previous neck exploration and resection of apparently benign adenomas. Long-term survival is possible with repeated resection of locally recurrent tumors. Long-term survival is possible with repeated resection of locally recurrent tumors.

Laparoscopic cholecystectomy is a viable and safe alternative for the treatment of symptomatic gallstones and biliary colic. As surgeons gain more experience with this procedure, contraindications become fewer and indications increase. Well-documented advantages of this approach include less patient discomfort, less surgical scarring, and earlier return to employment. Not previously discussed in the literature, however, are the additional advantages that this procedure holds for a specific subset of patients--namely, those patients that have undergone successful organ transplantation and are receiving immunosuppressive drugs. We report a case of a laparoscopic cholecystectomy in such a patient.

In 1987, a patient presented with pulmonary sarcoidosis and progressive renal failure. Percutaneous renal biopsy showed focal glomerular sclerosis (FGS). Over the subsequent 4-year period, her renal failure progressed to require hemodialysis. During this time, her pulmonary sarcoidosis was treated with daily corticosteroid therapy and she remained in clinical remission. The patient received a one-haplotype-identical living-related renal transplant from her mother. The patient is now 25 months posttransplant with a serum creatinine of 106 mumol/L (1.2 mg/dL). Her sarcoidosis continues to be in clinical remission. In this report, we review the rare association of a primary glomerular lesion causing renal failure in patients with sarcoidosis. In addition, we detail the first successful renal transplant in such a patient.

To the Editor: In their recent article, Elkouri et al described their experience with endovascular repair of abdominal aortic aneurysm (EVAR) in 100 consecutive patients treated between June 26, 1996, and October 31, 2001. On the basis of their high frequency of secondary procedures (29%) and early surgical conversion rate of 3%, the authors concluded that because early complications and reinterventions are frequent, “current data are insufficient to support EVAR as the preferred treatment of AAAs [abdominal aortic aneurysms].” Although not stated in the article, of the 5 endovascular devices used, 2 devices never completed clinical trials (EVT and Vanguard). A third, the ANCURE device, is no longer approved for clinical use. Early endograft designs were associated with many complications in midterm follow-up, with secondary intervention rates between 26.6% and 29%. These discouraging numbers with early devices, when compared with the excellent clinical results and lower costs of conventional AAA repair, caused some authors (circa 2001) to infer that the new EVAR technique might be “a failed experiment.” Since 1999, we have performed 160 EVAR procedures using Food and Drug Administration–approved devices. At 13-month follow-up, 11% of patients have needed secondary procedures, but no patient has undergone early conversion to open repair. In addition, aneurysm diameter decreased or was unchanged in 98% of patients. We conclude that EVAR is a reasonable alternative to open AAA repair in selected patients. We believe the discrepancy between the high technical success and the frequent secondary procedures and early complications described by Elkouri et al is based on the types of devices used. Our current series includes 87 AneuRx devices (Medtronic AVE, Minneapolis, Minn), 41 Zenith devices (Cook Group Inc, Bloomington, Ind), 18 Talent devices (Medtronic), 12 ANCURE devices (Guidant Corp, St Paul, Minn), and 2 EXCLUDER devices (W. L. Gore & Associates, Inc, Flagstaff, Ariz). These secondand third-generation devices include structural and delivery system modifications that increase the deployment success and decrease the limb complication rate.

To investigate the effects of aortic clamping and prostaglandin E1 on systemic hemodynamics and renal cortical and medullary blood flow by means of continuous intraparenchymal laser Doppler fluorometry.Experimental animal study in a porcine model. With the animal under general anesthesia after hemodynamic monitoring was instituted, surgical exposure was obtained through a small left retroperitoneal incision. The kidney was left undisturbed. Intraparenchymal laser Doppler probes (0.44 mm in diameter) were inserted in the renal cortex and medulla. In the first group of six animals, systemic hemodynamic variables, urine output and renal cortical and medullary flow were measured at baseline after 60 minutes of equilibration, and after 15 minutes of aortic clamping and unclamping. Data are given as mean +/- SE.In another six animals, prostaglandin E1 (20-micrograms intravenous bolus given over 1 minute) was given before clamping, and the same variables were recorded.In the first group, aortic clamping caused no change in cardiac output or filling pressures. Cortical blood flow decreased from 40.4 +/- 3.7 to 33.3 +/- 2.7 mL/100 g per minute (P.0004) after clamping, and to 27 +/- 2.3 mL/100 g per minute (P.0001) after unclamping, and was associated with a decrease in urine output from 3.2 +/- 0.5 to 2 +/- 0.2 mL/min (P.0013). Medullary flow remained the same at 9.2 +/- 0.8, 10 +/- 0.3, and 9.8 +/- 0.6 mL/100 g per minute, respectively. These adverse effects were prevented when prostaglandin E1 was given before clamping. There was an initial drop in blood pressure (100 +/- 4 to 89 +/- 5 mm Hg, P.0004), but cardiac output (43.3 +/- 5.8 L/min) and filling pressures (6 +/- 1 mm Hg) were unchanged. Cortical flow was preserved during the entire period of clamping and unclamping (43.3 +/- 5.8 mL/100 g per minute). Medullary flow remained unchanged (10 +/- 0.8 mL/100 g per minute). Urine output increased from 2 +/- 0.3 to 3.4 +/- 0.6 mL/min (P.006).In this animal model, infrarenal aortic clamping causes a significant decrease in renal cortical flow and urine output with no significant changes in filling pressures, cardiac output, or medullary blood flow. These adverse effects are prevented by pretreatment with prostaglandin E1, which prevents cortical ischemia and maintains brisk diuresis.

Spontaneous cholecystocutaneous fistula is rarely seen today because of the increased frequency and relative safety of biliary surgery. Chronic gallbladder inflammation secondary to calculous disease is the most frequent cause. Initial therapy consists of local drainage; a contrast-enhanced study of the fistulous tract should then be obtained. Definitive therapy consists of excision of the fistula, cholecystectomy, and intraoperative cholangiography. This problem occurs more frequently in the stoical, elderly patient with neglected biliary disease. A case is presented, along with a review of the literature.

PurposeSuprarenal fixation of aortic endografts appears to be a safe option in patients with a short or conical proximal aortic neck. However, concern persists regarding the long-term effect on renal function when renal artery ostia are crossed by the uncovered stent. We investigated the effect of suprarenal versus infrarenal endograft fixation on renal function and renal artery patency after endovascular aortic aneurysm repair.MethodsRecords of 91 patients who underwent endovascular aortic aneurysm repair with a modular bifurcated stent graft between November 1999 and January 2002 were reviewed retrospectively. Two patients receiving dialysis because of chronic renal failure were excluded. Infrarenal fixation was used in 57 patients (group 1), and suprarenal fixation was used in 32 patients (group 2). In two patients in group 1 a Gianturco Z stent was inserted transrenally because of intraoperative proximal type I endoleak, and data for these patients were excluded from analysis. Follow-up evaluation was performed at 1, 6, and 12 months, and yearly thereafter, and included clinical assessment, measurement of serum creatinine concentration (SCr), and computed tomography angiography, per standard protocol. Median follow-up was 12 months (range, 1-36 months).ResultsThere was no statistically significant difference in patient demographic data, aneurysm size, or preoperative risk factors. Median SCr was significantly higher in group 2 (suprarenal fixation) than in group 1 (infrarenal fixation) preoperatively (1.2 mg/dL [range, 0.6-2.3 mg/dL] vs 0.9 mg/dL [range, 0.6-1.9 mg/dL], P = .008) and at 1 month postoperatively (1.1 mg/dL [range, 0.8-5.6 mg/dL] vs 1.0 mg/dL [range, 0.6-2.1 mg/dL], P = .045). There was a significant increase in median SCr in both groups at 1 month postoperatively (group 1, 1.0 mg/dL [range, 0.6-2.1 mg/dL], P = .05; group 2, 1.1 mg/dL [range, 0.8-5.6 mg/dL] [mean SCr, 1.35 mg/dL vs 1.15 mg/dL, respectively], P < .05). In group 1 SCr was increased significantly at 6 and 12 months (P < .001), whereas in group 2 SCr also increased at 6 and 12 months, but not significantly. The change in SCr over time was not significantly different between the two groups. In two of 32 patients in group 2, renal artery occlusion developed, associated with perfusion defects in renal parenchyma and persistently elevated SCr. Analysis of renal artery patency did not demonstrate any association between patency and treatment. No patient developed hypertension during follow-up.ConclusionsSuprarenal endograft fixation does not lead to significant renal dysfunction, and renal artery occlusion is uncommon within 12 months. A larger study with longer follow-up is essential to determine overall effects on renal function and renal artery patency.

PurposeProximal endovascular aortic graft fixation and maintenance of hemostatic seal depends on the long-term stability of the aortic neck. Previous investigations of aortic neck dilation mostly focused on the infrarenal aortic diameter. Fenestrated and branched stent grafts facilitate suprarenal graft fixation and may thereby improve the long-term integrity of the aortic attachment site. For these devices, the natural history of the suprarenal aortic segment is also of interest. We investigated the natural history of the supra- and infrarenal aortic segment after open abdominal aortic aneurysm (AAA) repair.MethodsFor this retrospective analysis, we reviewed the preoperative and the initial postoperative as well as the most recent CT series that were obtained from 52 patients undergoing conventional repair of an infrarenal abdominal aortic aneurysm between January 1998 and December 2002. Measurements were performed using electronic calipers on a “split screen”, allowing direct comparison of subsequent CT series at corresponding levels along the vessel. Main outcome measures were changes in postoperative measures of the supra- and infrarenal aortic diameters.ResultsThe first postoperative exam was at a mean (±SD) of 7.0 ± 3.5 months, and the final exams were at 44.4 ± 21 months. Over this time period, the estimated rate of change in suprarenal diameter was 0.18 mm/ y with 95% confidence interval (CI) from 0.08 to 0.27. The estimated rate of change for the infrarenal diameter was 0.16 (95% CI: 0.05 to 0.27). A clinically relevant diameter increase of ≥3 mm was observed in seven patients (13%). There was evidence of larger diameter increases associated with larger AAA diameters (P = .003 and

In the two-stage mouse model for skin tumorigenesis with phorbol-12-myristate-13-acetate (PMA) as promoter, topical application of 40 microliters of toluene 2X/week at the initiation/promotion site (the back) reduced the average number of tumors/mouse (ANT/M) to approximately one-fourth that of controls. Control procedure involved initiation of C3H mice with benzo[a]pyrene (BaP) and CD-1 mice with 7,12-dimethylbenz[a]anthracene (DMBA) followed by promotion with from 1 to 5 micrograms PMA in 40 microliters acetone 2X/week. Forty microliters of toluene 2X/week per se was a weak promoter (6-13% of control ANT/M), and produced mild skin irritation at the application site but behavior and body weights were normal. The toluene inhibition of tumorigenesis was not a direct chemical action on PMA since similar effects occurred whether toluene was the vehicle for PMA or whether it was applied up to 1 day before PMA (i.e., prepromotion). Prepromotion with acetone had no effect on tumorigenesis, substantiating its use as control vehicle and suggesting that the toluene inhibition was a specific tissue reaction. The inhibitory effect appeared to be on PMA promotion rather than on initiation since toluene and acetone produced similar numbers of tumors when used as the vehicle for BaP or DMBA in two-stage or BaP in single-stage trials. The inhibition was not permanent since tumorigenesis returned to control rates 2-3 weeks after prepromotion with toluene ceased but promotion with PMA in acetone continued. Toluene may be unique among reported promotion inhibitors in that it is a widely used commercial chemical which sometimes serves as a vehicle in cancer-screening trials. Since its metabolism is reasonably well defined, it may be of value in exploring further the process of tumor promotion.