Improved patency after axillofemoral bypass for aortoiliac occlusive disease.

OBJECTIVE: Axillofemoral bypasses (AxFBs) have been used since 1962 to treat aortoiliac disease. In the past, reported patency rates (37%-76%) for these extra-anatomic grafts have been inferior to those for anatomic aortic grafting. Reported low survival rates after AxFB (40%-50%) have confirmed that these procedures have been used primarily in patients at high risk for complications from aortofemoral bypass. However, modern medical and anesthesia management, preoperative scanning, donor artery preparation, postoperative graft surveillance, and graft technology may improve outcomes after AxFB, possibly supporting expansion of its use. We therefore report our last 15-year experience with AxFB. METHODS: Ring-reinforced, 8-mm expanded polytetrafluoroethylene grafts were used in all cases. The cross-femoral limb of axillobifemoral bypass (AxBFB) grafts was preconstructed. Heparin was administered intraoperatively, with protamine reversal. Loss of primary patency was defined as graft thrombosis of part or all of the inserted graft. Five-year primary patency rates were calculated by Kaplan-Meier analysis. RESULTS: Between February 1991 and June 2016, a total of 161 grafts were inserted (85 AxBFBs and 76 axillounifemoral bypasses [AxUFBs]) in 91 male and 70 female patients (median age, 72.6 years; mean age, 73 years; range, 41-94 years). Indications for treatment were rest pain (49.6%), ischemic lesions (26%), claudication (22.3%), failed prior revascularization (9.3%), infection (3.7%), and dissecting aneurysm (1.2%). Reasons for performing AxFB rather than aortofemoral bypass were hostile aorta (44.1%), high risk (19.2%), prior failed reconstruction (12.4%), advanced age (8.7%), infection (4.3%), hostile abdomen (4.3%), aortic dissection (0.6%), and morbid obesity (0.6%). During follow up, 63 patients died, 17 within the first year; but only 3 patients died within 30 days of surgery (performed to treat an acute aortic occlusion). The 5-year survival rate was 55%. Five-year patency rates were 83.7% for all procedures, 81.8% for AxBFB, and 85.5% for AxUFB; the difference between AxBFB and AxUFB was not significant. CONCLUSIONS: Our data indicate that AxBFB and AxUFB performed with the use of modern protocols and technology may render them an acceptable valid primary intervention in patients in whom endovascular treatment has failed or is unlikely to offer long-term success. The simplicity of performing these grafts and their low mortality and morbidity lend their application to surgeons with limited open aortic experience. Because AxUFB and AxBFB have similar patency rates, AxBFB should be reserved for bilateral indications.

Heparin-bonded expanded polytetrafluoroethylene femoropopliteal bypass grafts outperform expanded polytetrafluoroethylene grafts without heparin in a long-term comparison.

OBJECTIVE: Expanded polytetrafluoroethylene (ePTFE) grafts have become an acceptable prosthetic alternative to autologous vein for infrainguinal arterial reconstructions. Recently, heparin bonding to the graft's luminal surface has been used as an adjunctive method of improving graft patency. We retrospectively evaluated a prospective experience with heparin-bonded ePTFE (HePTFE) vs the results of a prior experience with standard ePTFE (SePTFE) to compare patency rates in above-knee (AK) and below-knee (BK) femoropopliteal bypass through the 5-year follow-up. METHODS: Prosthetic femoropopliteal bypasses performed by our four-surgeon group were constructed using 6-mm SePTFE grafts before August 2007. Subsequently, all such bypasses were constructed using 6-mm HePTFE (Propaten graft; W. L. Gore & Associates, Flagstaff, Ariz). The surgical technique used in all cases throughout the study was similar irrespective of surgeon or graft material. Loss of primary patency was defined by graft thrombosis; duplex scan confirmed graft failure. Descriptive estimation of patency rates was carried out using standard Kaplan-Meier methods. Cox proportional hazards regression was used to analyze relationships between predictors and time to loss of patency. RESULTS: There were 192 AK (87 Propaten, 105 SePTFE) and 60 BK (42 Propaten, 18 SePTFE) grafts. Overall primary patency for Propaten was statistically better than SePTFE at years 1 (93.6% vs 84.2%), 2 (79.7% vs 73.8%), 3 (79.7% vs 69.5%), 4 (74.5% vs 59.9%) and 5 (74.5% vs 56.2%; log-rank test, P = .036). Five-year primary patency was superior for Propaten AK grafts (85.2% vs 59.3%; log-rank test, P = .028) and for Propaten BK grafts (59.6% vs 0.0/undeterminable; log-rank test, P = .016). Variables significantly associated with loss of patency for Propaten and SePTFE were claudication (hazard ratio [HR], 0.41), age (HR, 0.95), isolated popliteal artery (HR, 3.1-4.4), and ankle-brachial index after the procedure (HR, 0.10). Controlling for conduit effect, clopidogrel use did not significantly affect patency (P = .076). No grafts were associated with heparin-induced thrombocytopenia. CONCLUSIONS: These data show that the Propaten HePTFE graft offered significantly better long-term patency over the SePTFE graft, suggesting Propaten as the prosthetic graft of choice for bypasses to the femoropopliteal artery when autologous vein is unavailable or inappropriate.

Contralateral carotid artery occlusion is not a contraindication to carotid endarterectomy even if shunts are not routinely used.

OBJECTIVE: Although controversial, carotid artery stenting (CAS) has been proposed as being safer than carotid endarterectomy (CEA) for patients with a contralateral internal carotid occlusion (CCO). Arguably, with a CCO, CAS should be even safer than CEA if a shunt is not used. Accordingly, we reviewed our experience with 2183 CEAs performed routinely without a shunt to evaluate the risk of CEA performed in a subset of 147 patients with a CCO. METHODS: Between 1988 and 2011, 147 CEAs (111 men [75%], 36 women [25%]) were routinely performed without a shunt despite CCO. Of these patients, 76% were asymptomatic. CEAs were performed by seven surgeons using standard techniques (not eversion), with patients under general anesthesia and blood pressure maintained at >130 mm Hg. All patients received heparin (7500 U), and protamine reversal was routine. Median cross-clamp time was 20 minutes (range, 14-40 minutes). RESULTS: Three neurologic events occurred ≤ 30 days (2.0%). One transient ischemic attack (TIA) occurred immediately, and one occurred on the first postoperative day due to occlusion of the endarterectomy site. One patient sustained an immediate stroke and died of a large computed tomography-documented atheroembolic shower. CONCLUSIONS: Our data demonstrate the safety of CEA in the presence of a CCO, even when performed without a shunt. It is unlikely that the stroke or delayed TIA could be attributed to nonshunting or CCO. Even if so, the stroke and death rates would be lower than those previously reported for patients undergoing CEA in the presence of a CCO. This may be due to short cross-clamp times, careful technique, general anesthesia, and blood pressure support. Given these low adverse event rates, our experience refutes the assumption that patients with a CCO are at such a high risk for CEA that the only alternative is CAS.

Long-term safety of left renal vein division and ligation to expedite complex abdominal aortic surgery.

BACKGROUND: Left renal vein division and ligation (LRVDAL) is performed to facilitate complex abdominal aortic surgery. Surgeons restore continuity of the vein due to concern that ligation could cause renal compromise or hematuria. However, we report the short and long-term safety of left renal vein division and ligation. METHOD: Between 1992 and 2007, we divided the left renal vein in 56 patients (40 males, 16 females) ages 57 to 84 (average 74-years-old) who were treated for aortic occlusive disease (9) or abdominal aortic aneurysm (47). Patients requiring concomitant renal artery reconstruction were excluded from this review. Suprarenal cross-clamp was used in 51 patients with temporary vessel-loop control of the renal arteries. Creatinine (Cr) and glomerular filtration rates (eGFR) were measured pre-, post-, and long-term after surgery. Outpatient records of all patients that had survived more than 12 months were also reviewed in order to evaluate the late effects on renal function or symptoms possibly related to LRVDAL. RESULTS: Median procedure duration was 157 (61-375) minutes. Median cross-clamp time was 16 (10-45) minutes. Median intensive care unit (ICU) and hospital length of stays were 2 (1-11) days and 7 (4-58) days, respectively. There were no deaths. There were no complications directly related to renal vein ligation. Hematuria, seen in 2 patients, was a result of traumatic insertion of a Foley catheter. Median pre-op and discharge Cr levels were 1.1 mg/dL (0.7-2.4 mg/dL) and 1.1 mg/dL (0.6-2.1 mg/dL), respectively (P < .5). Median change in Cr was 0.0 mg/dL and only increased in 14 patients (maximum increase 0.9 mg/dL). Median pre-op and discharge eGFR was 61 mL/minute (28-137 mL/minute/1.73 m2) and 67 mL/minute (32-138 mL/minute/1.73 m2), respectively (P < .5). Cr and eGFR in the 2 patients with a Cr of >2.0 mg/dL remained unchanged post-op. Only 2 patients with a Cr of <2.0 mg/dL had a post-op Cr >2.0 mg/dL and both returned to normal by day 3 post-op. Thirty-six patients have been followed for more than a year (median 34.5 months, maximum 144 months) and Cr has remained stable in all but 2 patients. These 2 patients, both with a pre-op Cr of 1.5 mg/dL, subsequently developed Cr levels of 2.1 mg/dL and 2.4 mg/dL but maintained baseline Cr levels for 25 and 34 months, respectively, before demonstrating these elevated levels which have proven to be unrelated to renal vein ligation. Hematuria and flank pain have never been recorded after discharge. CONCLUSION: Restoration of left renal vein continuity after LRVDAL may be unnecessary since renal compromise and hematuria was not encountered in this long-term analysis.

CryoPlasty therapy of the superficial femoral and popliteal arteries: a reappraisal after 44 months' experience.

OBJECTIVES: Long-term patency remains a significant hurdle in the minimally invasive treatment of arteriosclerosis in the superficial femoral (SFA) and popliteal arteries. CryoPlasty therapy (PolarCath, Boston Scientific Corp, Natick, Mass) is a novel approach designed to significantly reduce injury, elastic recoil, neointimal hyperplasia, and constrictive remodeling. The technique combines the dilatation forces of percutaneous transluminal angioplasty (PTA) with cold thermal energy applied to the plaque and vessel wall. We previously reported a technical success rate of 96% and a 12-month freedom from restenosis rate of 82.2%. However, a review of the original cohort supplemented by experience with a further 47 lesions has demonstrated less desirable results. METHODS: From December 2003 through July 2007, 92 lesions in 64 consecutive patients were treated and followed up for a median of 16 months with statistically significant follow-up at 24 months. RESULTS: The immediate technical success rate was 88%. Nine stents were immediately required after unsuccessful CryoPlasty (9.8%) five of which were as a result of a dissection. No unanticipated adverse events occurred, specifically, no thrombus, acute occlusions, distal embolizations, aneurysms, or groin complications. Vascular calcification was responsible for technical failure in six of the 11 immediately unsuccessful procedures. Freedom from restenosis for successfully treated lesions was 57% and 49% at 12 and 24 months, respectively. CryoPlasty of heavily calcified lesions, vein graft lesions, and in-stent stenosis faired poorly. Excluding these lesions from analysis would have resulted in an immediate success of 94% (81 of 86) and freedom from restenosis of 61% and 52% at 12 and 24 months, respectively. However, on an intention-to-treat basis, freedom from restenosis was 47% and 38% at 12 and 24 months, and CryoPlasty added approximately $1700 to the cost of each procedure. CONCLUSION: Analysis of this expanded, longer-term data suggests that our earlier, smaller study provided an overly optimistic appraisal of the benefits of CryoPlasty. It is possible that a larger analysis might have identified a subset of patients or lesions that would benefit from CryoPlasty, but considering the additional cost, we no longer use this technique in our practice.

CryoPlasty therapy of the superficial femoral and popliteal arteries: a single center experience.

Long-term patency remains a significant hurdle in the minimally invasive treatment of arteriosclerosis in the superficial femoral and popliteal arteries. New technologies designed to address the sources of restenosis have recently been introduced. CryoPlasty therapy (Boston Scientific, Natick, Mass) is a new approach designed to significantly reduce injury, elastic recoil, stent implantation, neointimal hyperplasia, and constrictive remodeling. The technique combines the dilatation forces of percutaneous transluminal angioplasty with cold thermal energy applied to the plaque and vessel wall. The cumulative effect of limiting the sources of restenosis with CryoPlasty therapy was shown to demonstrate longer term patency in a prospective, multicenter, Investigational Device Exemption study of the PolarCath Peripheral Dilatation System. The CryoPlasty therapy experience of 1 center is reported, in which 47 lesions in 32 consecutive patients (34 procedures, 33 limbs) were treated. The technical success rate was 96%. There were no type 3 flow-limiting dissections, and only 4 (8.5%) lesions were stented. There were no unanticipated adverse events, specifically no thrombus, acute occlusions, distal embolizations, aneurysms, or groin complications. With an average follow-up of 12 months, only 5 lesions have recurred, 4 requiring re-intervention. The 12-month freedom from restenosis for lesions and limbs treated was 82.2% and 84.4%, respectively. These results are similar to the findings of the Investigational Device Exemption study and are encouraging. CryoPlasty therapy appears to be a viable endovascular therapeutic option to achieve longer term patency without compromising options for future interventions. The lack of early occlusions may be due to a low rate of spiral dissection that may be a particular benefit of this form of angioplasty.

Homocysteine, a risk factor for carotid atherosclerosis, is not a risk factor for early recurrent carotid stenosis following carotid endarterectomy.

Homocysteine has been proposed as a risk factor for atherosclerotic disease and recurrent coronary stenosis due to neointimal hyperplasia following angioplasty. In order to evaluate homocysteine's role in human carotid neointimal hyperplasia, we have compared homocysteine levels in patients who have not developed restenosis with those who have within 2 years of carotid endarterectomy (CEA). One hundred and fifty-four patients were divided into 3 groups based on duplex scans performed 2 years after CEA. Group I (88) were patients in whom all scans showed no evidence of restenosis. Group II (35) patients exhibited some restenosis, but this did not exceed 49% diameter reduction based on our duplex criteria. Group III (31) patients developed a restenosis of > 50% within 2 years. One hundred and thirteen Dacron patches (73 Group I [83%], 22 Group II [63%], and 18 Group III [58%]) were used according to surgeon preference but did not affect the statistical relevance of homocysteine evaluation. The groups were otherwise identical in terms of age, sex, smoking history, and cholesterol levels. All patients were receiving antiplatelet medication postoperatively, and none had consumed added pharmacologic folate. The average homocysteine value for the entire study group was elevated at 12.5 micromol/L. The homocysteine values for the 3 groups were not statistically different (p > 1): (I, 12.5; II, 12.2; and III, 12.9 micromol/L). Elevated homocysteine levels (> 10 micromol/L) appear to be associated with carotid atherosclerosis, but at levels < 30 micromol/L do not appear to play a role in restenosis following CEA.