Faculty Bibliography

BACKGROUND: Radiofrequency ablation (RFA) is a widely accepted alternative to high ligation with proximal stripping of the great saphenous vein (GSV) in the treatment of lower extremity venous insufficiency. This study compared short-term outcomes of two generations of (VNUS Closure) RFA catheters, ClosurePlus (CP) and ClosureFast (CF). METHODS: From February 2005 to April 2009, a total of 667 consecutive office-based RFA procedures were performed in our institution. CP catheters were used in the initial 312 lower extremity cases and CF catheters in the 355 cases that followed. The technique used for both catheters were as per the manufacturer's recommendations. Postoperative duplex scans were completed to document the following endpoints: GSV obliteration; incidence of deep venous thrombosis (DVT); superficial venous thrombosis (SVT); and presence of loose or floating thrombus proximal to the treated GSV segment. RESULTS: Of the 667 cases, 98% had available duplex scan studies within 1 week from completion of the procedure. Complete obliteration of the GSV on duplex scan studies was noted in 98% of 343 cases using the CF catheter and 88% of 312 cases using the CP catheter (P < .001). No case of DVT was detected in those treated with the CF catheter, whereas DVT occurred in 3.5% of cases treated with the CP catheter (P < .001). Incidence of SVT was 10% and 15%, respectively, for CF and CP (P < .08). Loose thrombus proximal to the GSV was identified in 7% of cases using CF and 6% of cases using CP (P = .80). No embolic episodes were observed clinically. CONCLUSIONS: CF catheters are superior to CP catheters in terms of GSV obliteration and nonincidence of postoperative DVT. The absence of DVT may likely be due to the commencement of ablation at 2 cm from the GSV-common femoral vein junction.

BACKGROUND: Venous outflow obstruction may play a role in patients with chronic venous stasis symptoms who fail to improve despite conventional modalities of treatment that focus on the reflux component of the disease with little attention to the possibility of an obstructive component. The introduction of minimally invasive venous stenting using venography and intravenous ultrasonography (IVUS) provides the ability to treat the "obstructive" component of the disease. METHODS: We undertook a retrospective review of 56 limbs in 53 patients with chronic venous stasis symptoms. Initial transcutaneous Doppler ultrasonographic evaluation of the inferior vena cava, iliac, femoral, greater saphenous, and perforator veins was performed looking for any evidence of deep venous thrombosis, superficial venous thrombosis, perforator veins, and reflux (location and degree). Afterword, the patients were managed in the conventional fashion (leg elevation, compression, and great saphenous vein (GSV) and perforator ablation, if present) for a period of 3 months. If ulcer healing was not noted, iliac-femoral venography and IVUS were undertaken. A significant stenosis was defined as a 50% reduction in vein cross-sectional area as measured by IVUS.(1,2,3) Stenotic lesions were managed with stenting followed by balloon angioplasty. Patients were followed up for ulcer healing or improvement of stasis symptoms. RESULTS: Of the 56 limbs, 10 (17.8%) had postthrombotic changes, 7 (12.5%) had incompetent perforators, and 27 (48.2%) had an incompetent superficial venous system. In the stented group (n = 29), 3 limbs had perforator ablation alone, 13 limbs had GSV ablation alone, and 1 limb had both perforator and GSV ablation. In the unstented group (n = 27), 10 limbs had GSV ablation alone, and 3 limbs had both perforator and GSV ablation. The overall incidence of deep reflux was 51.8%; 17 of 29 limbs (58.6%) in the stented group had evidence of deep reflux, and 12 of 27 limbs (44.4%) in the unstented group had deep reflux. All venograms except one (98.2%) were performed under local anesthesia with sedation. The procedure was performed in an ambulatory setting in 69.6% (39 of 56) of the limbs. CEAP clinical severity class distribution was as follows: C2, 4%; C3, 16%; C4, 18%; C5, 5%; C6, 57%. Over half of the limbs (29 of 56) were found to have stenotic lesions and required stenting. Eight patients (11 limbs) did not return for ulcer healing assessment. The majority (19 of 29) of limbs in the stented group had a CEAP of 6. Among the patients with CEAP 6 who returned for follow-up (n = 26), 7 had no evidence of stenosis and required no stenting. Only one of those (14.3%) healed his ulcers after 3 months (average follow-up of 4.8 months). The remainder 19 limbs were found to have stenotic lesions and underwent stenting. The ulcers healed in 11 of those (58%) over a period of 1 week to 8 months (average of 5 months), with average follow-up of 3.6 months (p = 0.08). The cumulative primary and secondary patency rates were 93.1% (27 of 29) and 100% (29 of 29), respectively. Two stent thromboses occurred within 4 weeks of the initial procedure. Both occurred in patients with postthrombotic obstruction. One patient developed a superficial femoral artery pseudoaneurysm. CONCLUSION: Over half of our patients with open ulcers had stenotic lesions. The ulcers healed in 58% of the stented limbs. That indicates that outflow obstruction may play a significant role in patients with chronic venous stasis symptoms, especially those with open ulcers who failed to respond to other treatment modalities. The procedure itself is relatively safe and simple and can be performed on an ambulatory basis.

Infra-popliteal veins include the tibial and peroneal veins, as well as the soleal and gastrocnemial veins collectively known as the calf muscle veins (CMVs). Acute infra-popliteal deep venous thrombi (DVTs) are often considered insignificant with regard to the risk of pulmonary embolism (PE). A retrospective review of 4035 consecutive lower extremity venous duplex scans were made in 3146 hospital patients at our Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL)-accredited vascular lab. Seven hundred sixteen (17.7%) duplex scans were positive for acute DVTs, and 112 (2.8%) were associated with PEs. The breakdown of positive duplexes for acute DVTs was as follows: 202 (28.2%) isolated femoral-popliteal DVTs with PE in 23 (11.4%), 304 (42.5%) isolated infra-popliteal DVTs with PE in 24 (7.9%) and 210 (29.3%) multilevel DVTs involving both vein segments (femoral-popliteal and infra-popliteal) with PE in 38 (18.1%). Of the 304 isolated acute infra-popliteal DVTs, 207 (68.1%) were isolated CMV DVTs with evidence of PE in 12 (5.8%). No statistically significant difference (P = 0.27) in the risk of PE between isolated femoral-popliteal and isolated infra-popliteal DVTs was noted. A significant number of patients (5.8%) with isolated CMV DVTs developed PE. Lower limb venous scans for DVTs should evaluate the infra-popliteal veins. Hospitalized patients with infra-popliteal DVTs should receive anticoagulation.

BACKGROUND: The technique of long segment stenting of the superficial femoral artery (SFA) has been associated with poorer short- and long-term results. The full metal jacket (FMJ) stenting is typically described as long segment continuous stenting of a vessel segment. Initially, this technique was described in percutaneous coronary interventions. However, until recently, FMJ of the SFA has not been studied. We examined our experience with FMJ of the SFA to evaluate the outcomes and the safety of this technique. METHODS: Retrospective data were gathered for peripheral angioplasties and stenting for the period between January 2005 and December 2008. The cases involving FMJ stenting of the SFA were identified by angiographic findings and the operative dictations providing the stent data. Selective FMJ stenting of the SFA was performed for the residual stenosis after balloon angioplasty of the SFA because of either dissection or significant recoil. The cases with concomitant iliac artery angioplasty and/or stenting were excluded from the data set for analysis. The variables for the evaluation were primary patency rate, mortality rate, and limb salvage rate, which were stratified on the basis of the risk factors. RESULTS: A total of 63 cases involving FMJ stenting of the SFA were identified from the database of 707 patients who had peripheral endovascular interventions between January 2005 and December 2008. Average age of the patients was 70 years (range: 52-104 years, SD: 10.1 years). There were no transatlantic inter-society consensus (TASC) A lesions, 11% (7/63) of the lesions were TASC B, 68% (43/63) were TASC C, and 21% (13/63) were TASC D. The median primary patency rate was 9 months (95% CI: 5.06-12.94). The mortality rate was 4% at 6-month follow-up. The limb salvage rate was 85.7%. In all, 65% (41/63) of the patients were claudicants, whereas 23% (15/63) had intervention for some form of tissue loss (ischemic ulcer, gangrene). Associated infrapopliteal intervention was performed in 15.9% of the patients. Average creatinine level was 1.67 (range: 0.7-10.9, SD: 2.03) and 49% (31/63) of the patients had diabetes. The average 6-month patency rate was 55% (SD: 0.5). Multivariate logistic regression analysis showed that diabetes (OR: 0.33, p = 0.044, 95% CI: 0.11-0.97) and a creatinine level of >/=1.6 (OR: 0.16, p = 0.038, 95% CI: 0.03-0.9) were the independent risk factors for loss of patency in <6 months. CONCLUSION: Our experience suggests promising results for the technique of FMJ of the SFA and also that further examination of the technique is warranted.

The objective of this study was to evaluate the feasibility of duplex scanning-derived access volume flow (DAVQ) to predict the success or failure of arteriovenous fistulae (AVF) after interventions. Eighty-eight DAVQ measurements were available for 60 AVF in 59 patients. In 25 cases, physical examination findings or inadequate dialysis suggested failing (11) or nonmaturing (14) AVF. Outflow stenoses (1-4; mean 1.2 +/- 0.8) were confirmed by contrast fistulograms in 23 cases (17 peripheral; 6 central). These 23 cases underwent successful endovascular repair (17 balloon angioplasty; 6 stents) and had pre- and postintervention DAVQ measurements within 2 weeks of the procedure. Each was measured three times in a nontortuous venous segment with laminar flow, and mean values were used for comparison. The overall mean DAVQ for 65 functioning AVF was 1,199 +/- 485 mL/min, whereas it was 652 +/- 438 mL/min (range 150-1,840 mL/min) for the remaining 23 failing or nonmaturing cases (p < .0001). Postintervention, the latter values changed to 867 +/- 517 mL/min (range 257-2,020 mL/min), with a p < .13. Of these, 11 were still nonfunctional after endovascular procedures and had a mean DAVQ of 404 +/- 111 mL/min (range 257-652 mL/min). The remaining 12 cases had a mean DAVQ of 1,280 +/- 382 mL/min (range 762-2,020 mL/min) and were functional and usable for at least 6 months of follow-up (p < .0001). It is interesting to note that none of the AVF cases with postintervention DAVQ < 700 mL/min became functional and usable, whereas all cases with a higher DAVQ underwent successful hemodialysis treatments. This early experience suggests that DAVQ can be used to predict the success or failure of an AVF following endovascular procedures. To our knowledge, this is the first such report.