Prospective randomized trial of ACUSEAL versus Vascu-Guard patching in carotid endarterectomy.

BACKGROUND: Multiple studies have been conducted that demonstrate the superiority of patch angioplasty over primary closure for carotid endarterectomy (CEA). Patch angioplasty with polytetrafluorethylene patches (ACUSEAL) have shown results comparable to patch angioplasty with saphenous vein and polyester patches. This is a prospective randomized study to compare the clinical outcomes of CEA using ACUSEAL versus bovine pericardium patching (Vascu-Guard). METHODS: Two hundred patients were randomized (1:1) to either ACUSEAL or Vascu-Guard patching. Demographic data/clinical characteristics were collected. Intraoperative hemostasis times and the frequency of reexploration for neck hematoma were recorded. All patients received immediate and 1-month postoperative duplex ultrasound studies, which were repeated at 6-month intervals. A Kaplan-Meier analysis was used to estimate the risk of restenosis and the stroke-free survival rates. RESULTS: The demographics were similar in both groups, except for a higher incidence of current smokers in the ACUSEAL group and more patients with congestive heart failure in the Vascu-Guard group (P = 0.02 and 0.03, respectively). The mean operative internal carotid artery diameter and the mean arteriotomy length were similar in both groups. The mean hemostasis time was 4.90 min for ACUSEAL patching vs. 3.09 min for Vascu-Guard (P = 0.027); however, the mean operative times were similar for both groups (ACUSEAL 2.09 hr vs. Vascu-Guard 2.16 hr, P = 0.669). The incidence of reexploration for neck hematoma was higher in the Vascu-Guard group; 6.12% vs. 1.03% (P = 0.1183). The incidence of perioperative ipsilateral neurologic events was 3.09% for ACUSEAL patching vs. 1.02% for Vascu-Guard patching (P = 0.368). The mean follow-up period was 15 months. The respective freedom from ≥70% carotid restenosis at 1, 2, and 3 years were 100%, 100%, and 100% for ACUSEAL patching vs. 100%, 98%, and 98% for Vascu-Guard patching (P = 0.2478). The ipsilateral stroke-free rates at 1, 2, and 3 years were 96% for ACUSEAL and 99% for Vascu-Guard patching. CONCLUSIONS: Although CEA patching with ACUSEAL versus Vascu-Guard differed in hemostasis time, the frequency of reexploration for neck hematomas was more frequent in the pericardial patch group; however, only 1 patient had documented suture line bleeding and the surgical reexploration rate is not likely to be patch related. There were not any significant differences in perioperative/late neurologic events and late restenosis in the 2 groups.

Radiocephalic fistula: review and update.

Since initially described in 1966, radiocephalic fistula or Brescia-Cimino fistula is one of the most commonly performed fistulas in the world of arteriovenous access. The indications for insertion include, but are not limited to, hemodialysis. Although this is a frequently performed procedure, the primary and secondary patency rates and predictors of failure are not well defined. The review of this topic is difficult because of the diversity in reporting and the absence of consensus between series. Following the current published recommendations by the Society of Vascular Surgery regarding standardization of terminology to facilitate meaningful comparison between the diversity of published data, this review is an attempt to summarize and highlight the relevant information with regard to primary patency, secondary patency, and predictors of failure of radiocephalic fistula using the available English literature.

Critical analysis of renal duplex ultrasound parameters in detecting significant renal artery stenosis.

BACKGROUND: Several published studies have reported differing results of renal duplex ultrasound (RDU) imaging in detecting significant renal artery stenosis (RAS) using different Doppler parameters. This study is the largest to date to compare RDU imaging vs angiography and assess various published Doppler criteria. METHODS: RDU imaging and angiography were both done in 313 patients (606 renal arteries). RAS was classified as normal, <60%, ≥ 60% to 99%, and occlusion. Main outcome measurements included renal peak systolic velocity (PSV), systolic renal-to-aortic ratio (RAR), end-diastolic velocity (EDV), and kidney lengths. RESULTS: The mean PSVs and RARs for normal, <60%, and ≥ 60% stenosis were 173, 236, and 324 cm/s (P < .0001), and 2.2, 2.9, and 4.5, respectively (P < .0001). The PSV cutoff value that provided the best overall accuracy for ≥ 60% stenosis was 285 cm/s, with a sensitivity, specificity, and overall accuracy of 67%, 90%, and 81%, respectively. The RAR cutoff value with the best overall accuracy for ≥ 60% stenosis was 3.7, with a sensitivity, specificity, and overall accuracy of 69%, 91%, and 82%, respectively. A PSV of ≥ 180 cm/s and RAR of ≥ 3.5 had a sensitivity, specificity, and overall accuracy of 72%, 81%, and 78% in detecting ≥ 60% stenosis. A PSV of ≥ 200 cm/s with an RAR of ≥ 3.5 had a sensitivity, specificity, and overall accuracy of 72%, 83%, and 78% in detecting ≥ 60% stenosis. A receiver operator characteristic (ROC) curve analysis showed that the PSV and RAR were better than the EDV in detecting ≥ 60% stenosis: PSV area under the curve (AUC) was 0.85 (95% confidence interval [CI], 0.81-0.88), EDV AUC was 0.71, and RAR AUC was 0.82 (PSV vs EDV, P < .0001; PSV vs RAR, P = .075; EDV vs RAR, P < .0001). A PSV of 285 cm/s or RAR of 3.7 alone were better than any combination of PSVs, EDVs, or RARs in detecting ≥ 60% stenosis. The mean kidney length was 10.4 cm in patients with ≥ 60% stenosis vs 11.0 cm in patients with <60% stenosis (P < .0001). Twelve percent of patients with ≥ 60% stenosis had a kidney length of ≤ 8.5 cm vs 4% in patients with <60% stenosis (P = .0003), and 5.6% (34 of 606) had accessory renal arteries on angiography, with six detected on RDU imaging. The presence of accessory renal arteries, solitary kidneys, or renal fibromuscular dysplasia had no influence on overall accuracy of using PSV values for detecting ≥ 60% stenosis. CONCLUSIONS: A PSV of 285 cm/s or an RAR of 3.7 alone can be used in detecting ≥ 60% RAS. Previously published data must be validated in individual vascular laboratories.

Primary stenting of the superficial femoral and popliteal artery.

OBJECTIVES: Over the last decade, the number of endovascular procedures performed on the superficial femoral (SFA) and popliteal arteries (PA) has significantly increased. There is no consensus on the optimal form of intervention used in this arterial segment. While some have advocated balloon angioplasty alone, others have championed either selective or primary stenting of these lesions. It is the purpose of this study to determine the efficacy and durability of primary stenting of the superficial femoral and popliteal artery. METHODS: All patients undergoing peripheral angioplasty by a single vascular surgeon were prospectively enrolled in an Institutional Review Board-approved, primary-stenting protocol. During a 44-month period, all patients undergoing percutaneous transluminal angioplasty of the SFA or PA also received primary arterial stenting with bare, self-expanding nitinol stents. Patient demographics and risk factors were identified. TransAtlantic InterSociety Consensus (TASC) classifications were determined for all lesions. Loss of primary patency was said to have occurred when an occlusion or a 50% or greater stenosis in any treated arterial segment was diagnosed by arterial duplex or angiography. Only time to loss of primary patency was recorded. Kaplan-Meier survival curves were plotted and differences between groups tested by log rank method. RESULTS: Between January 16, 2004 and August 13, 2007, 201 angioplasties with primary stenting were performed on 161 patients. One hundred twenty-three stents were placed for claudication, and 78 for critical limb ischemia. Forty-six segments treated were TASC A, 82 were TASC B, 38 were TASC C, and 35 were TASC D. Patient follow-up ranged from three to 1329 days (mean: 426 days). Primary patency rates for TASC A and B lesions were 79%, 67%, and 57% at 12, 24, and 36 months. For TASC C and D lesions, primary patency rates were 52.7%, 36%, and 19% at the same time intervals. Primary patency rates for TASC A and B lesions were significantly higher than for C and D lesions (P < .001). The limb salvage rate was 88.5% in patients with critical limb ischemia. Distal runoff did not influence patency (P = .827). CONCLUSIONS: Primary stenting of the SFA and PA provides durable results in patients with TASC A and B lesions and may be an effective treatment strategy. This approach is significantly less effective when used in treating those with TASC C and D disease. Based on the results in this series, the use of primary stenting does not extend the anatomic limits of the current treatment recommendations for catheter-based intervention in patients with infrainguinal occlusive disease.