Faculty Bibliography

Background Dialysis access-associated steal syndrome is a major complication of arteriovenous fistula creation whereby the low-resistance venous conduit shunts arterial inflow through the anastomosis, resulting in clinically significant distal artery insufficiency. Herein, we describe a case of severe steal phenomenon with gangrene of a digit following placement of an arteriovenous fistula that was treated with a novel, entirely endovascular technique. To our knowledge, this was the first totally endovascular approach to dialysis access-associated steal syndrome. Methods Catheterization of the right subclavian, axillary, and brachial arteries was performed. A short 5-Fr sheath was exchanged for a long destination 6-Fr sheath and placed in the proximal brachial artery. An arteriogram showed no stenosis of the arterial system, but did show substantial steal phenomenon with inflow to the arteriovenous fistula, instead of the forearm. We placed a stent graft in the brachial artery across the anastomosis such that the graft covered 3/4 of the length of the opening of the anastomosis. Results Immediately after placement of the stent graft the clinical picture improved dramatically. Patient was followed for 15 months after this procedure until her demise for unrelated causes without ever experiencing dialysis access-associated steal syndrome and with a patent and functional arteriovenous fistula. Conclusion We present a patient with severe dialysis access-associated steal syndrome complicated by third fingertip gangrene, which was successfully treated using a completely endovascular technique. This novel endovascular approach enabled a high-risk patient to avoid open surgery, preserve her limb, and maintain the function of her arteriovenous fistula.

Objective With the implementation of the K-DOQI guidelines, more patients are in need of long-term dialysis catheters until maturation of the arteriovenous fistula. However, on occasion, when placing a tunneled cuffed catheter for hemodialysis, we have encountered difficulty with passing the guidewire in spite of demonstration of a patent cervical portion of the internal jugular vein on duplex. Herein, we review our experience with intraoperative venoplasty for placement of Tesioâ„¢ catheters (Medcomp Harleysville, PA). Methods Of the 1147 Tesioâ„¢ catheters placed since 1997 by our service, 35 venograms were performed due to difficulty encountered with placement of the guidewire. Patent veins were all crossed with the use of angle-guiding catheters, angled glidewires, and a torque vise. If chronically occluded intrathoracic veins were identified, an alternate site was selected for the placement of the Tesioâ„¢ catheter. Results Of the 35 cases with difficulty in catheter placement, venogram demonstrated a patent but tortuous vein in 9, chronically occluded intrathoracic veins in 6, and severe stenosis of the intrathoracic veins in 20. In 19 cases with severe stenosis of the intrathoracic veins, balloon angioplasty with an 8-mm balloon was successfully performed, which allowed successful placement of a functional Tesioâ„¢ catheter. In the additional one case, the catheter was not able to be placed despite angioplasty. Seven lesions that underwent balloon angioplasty were in the innominate vein, 11 were in the proximal internal jugular vein, and two were in the superior vena cava. Conclusion Venous balloon angioplasty can be used to maintain options for the site of access for tunneled cuffed catheters and may be necessary to assist with placement of long term cuffed dialysis catheters.

Objectives The use of postoperative anticoagulation is not uncommon for patients undergoing lower extremity arterial procedures as adjunctive therapy. Longer postoperative length of stay is necessary to achieve adequate therapeutic international normalized ratio with traditional protocols that call for the use of unfractionated heparin and warfarin therapy. We hypothesized the direct oral anticoagulants are an attractive alternative to provide adequate anticoagulation in patients who undergo lower extremity arterial procedures. Methods We retrospectively studied patients who had lower extremity arterial procedures between 2012 and 2015 to examine the safety and efficacy of the direct oral anticoagulants in a single institution. Patency, freedom from re-intervention, and major adverse limb event were evaluated. The direct oral anticoagulant agents used included dabigatran, rivaroxaban, and apixaban. The primary patency, adverse effects and freedom from re-intervention were then compared to a control group of patients who were treated with traditional heparin-warfarin therapy after lower extremity bypass procedures. Results Direct oral anticoagulants were utilized in a total of 23 patients (48% men; mean age 69 ± 11 years) during the study period. Indication for use of direct oral anticoagulant after procedure included use of polytetrafluoroethylene (PTFE) bypass graft below the knee joint or after lower extremity angioplasty with disadvantaged runoff. Mean follow-up of the drugs was 23 months (SD ± 16 months). At the end of follow-up, the direct oral anticoagulants have been discontinued in four patients, who are currently only on plavix. Among 82.6% of patients who were given direct oral anticoagulants for PTFE bypasses, graft patency, freedom from re-intervention, and major adverse limb event were 100%, 100%, and 0%, respectively. Patients (17.4%) treated with direct oral anticoagulants for disadvantaged runoff after balloon angioplasty of the lower extremity, patency, freedom from re-intervention, and major adverse limb event were 100%, 100%, and 0%, respectively. For the patients who underwent direct oral anticoagulant administration for disadvantaged runoff primary patency was 100%. One patient developed wound dehiscence which was unrelated to direct oral anticoagulant administration. Our control group consisted of 100 patients who were treated with heparin-warfarin therapy for 30 days after lower extremity bypass procedures. The graft patency, freedom from intervention, and major adverse limb event were 93%, 12%, and 0%, respectively. There was however no statistically significant difference in graft patency rate ( P = .34) or freedom from intervention ( P = .07) between the two groups. Conclusions The preliminary data suggest that there may be a role for using the direct oral anticoagulants with patients who undergo lower extremity arterial procedures for prevention of thrombosis and warrants further investigation.

Objective The purpose of the study is to evaluate normal anatomical areas of infrarenal inferior vena cava, common iliac, external iliac and common femoral veins by intravascular ultrasound with the goal of assisting the development of venous-specific stents in the treatment of iliac vein stenosis. Method From February 2012 to December 2013, 656 office-based venograms were performed in our facility. Among them, 576 were stented and 80 were not. The measurements of veins were done intraoperatively using an intravascular ultrasound catheter to record areas of the inferior vena cava, proximal, middle and distal segments of common iliac vein, external iliac vein and common femoral vein. The data were compared between non-diseased segments of patients who were stented and those not stented. The stented diseased segments were excluded. Results The mean patient age was 67.33 years (range 22-96, SD ±13.99). Our data included 218 males, 438 females and 324 right lower extremities and 332 left lower extremities. The presenting symptoms of these patients based on CEAP were C1(0), C2 (185), C3(233), C4(107), C5(89) and C6(42). No correlation was found between area of veins and age, gender, laterality and CEAP score (P > .13). Comparison of the areas of non-diseased iliac vein segments between patients not stented and patients who underwent stenting showed a significant difference, with larger areas in non-stented patients in the distal common iliac vein (P = .039) and inferior vena cava (P = .012). Younger age (P = .03) and male gender (P < .0001) were associated with increased area of iliac vein segments. Conclusion Utilizing the intravascular ultrasound-guided technique, we were able to define normal anatomical areas of non-diseased inferior vena cava, iliac and femoral veins, which could be employed to guide the development of appropriate-sized stents and other tools needed for the treatment of venous insufficiency. There is specific variability in areas of normal vein segments with age and gender with/without stents.

OBJECTIVE:The purpose of the study was to aggressively salvage acutely occluded arteriovenous fistulas (AVFs) using duplex imaging as the sole imaging modality for percutaneous transluminal angioplasty of acutely thrombosed AVF. METHODS:Over a period of 12 months, 14 patients with acute thrombosis of their AVFs underwent 18 procedures in a single center for AVF salvage. All 14 patients presented with chronic renal failure, and six were diabetic. All patients were treated under duplex guidance alone. Treatment included simple balloon dilation and maceration (group A; n =10 procedures [56%]) for subacute thrombosis or pharmacomechanical thrombectomy (group B; n = 8 procedures [44%]) for more hypoechoic thrombus. A successful procedure was defined as immediate restoration of flow through the AVF. RESULTS:Of the 18 procedures, 13 (72%) were successful. Of the 14 patients, thrombus was located at the perianastomotic AVF in 6 (43%), proximal-mid AVF in 6 (43%), mid AVF in 1 (7%), and distal AVF in 1 (7%). From group A, six (60%) were successful. From group B, seven (88%) were successful. Among the unsuccessful procedures, one group B patient was hypercoagulable (polycythemia vera). Of the 18 procedures, 16 (89%) were treated within 2 weeks from when duplex revealed the presence of thrombus. Early rethrombosis (<1-month patency) occurred in three cases (17%), and these patients received new fistulas. Full restoration of the fistula flow was established in 14 cases (78%). Of these 14 patients, 8 (57%) are currently on hemodialysis via fistula, 3 patients (21%) had newly placed fistulas after failed interventions, 2 patients (14%) are not on dialysis yet, and 1 patient (7%) with polycythemia vera disorder is on dialysis via a Tesio catheter (MedComp, Harleysville, Pa). CONCLUSIONS:The sole use of duplex ultrasound imaging to salvage acutely occluded AVFs using percutaneous transluminal angioplasty is a safe and effective alternative to traditional treatment of thrombosed failing/maturing AVF.

Objectives Treatment options for venous insufficiency are rapidly evolving in the office setting and include venography, intravascular ultrasound, and venous stenting. Non-thrombotic iliac vein lesions assessment and treatment in an office setting is currently an area of interest. The purpose of this study is to demonstrate the safety and efficacy of evaluating non-thrombotic iliac vein lesion with this office-based procedure in octogenarians and nonagenarians. Methods From January 2012 through December 2013, 300 non-thrombotic iliac vein lesion limbs in 192 patients with venous insufficiency ≥80 years old were evaluated for non-thrombotic iliac vein lesion. Patients were evaluated and treated with venography, intravascular ultrasound, and stent placement for significant lesions demonstrated by greater than 50% diameter or cross-sectional area reduction. Group 1: 168 of these patients were octogenarians; female/male ratio was 1.75:1, bilateral in 89/168 patients (53%), left sided in 131/259 limbs (51%), right sided in 128 limbs (49%), average age 83.5 ± 2.6 years (range 80-89) compared to Group 2: 24 nonagenarians; female/male was 3:1, bilateral in 17/24 patients (70%), left sided in 20/41 limbs (49%), right sided in 21/41 limbs (51%), average age 92.9 ± 2.2 years (range 90-99). Stent related outcomes were evaluated with communication to the patient within 24 h to assess post-procedure pain followed by serial iliocaval ultrasonography. Results Out of the 300 limbs evaluated, in Group 1, 86% of limbs had stents placed compared to 90% in Group 2 and 11% of both groups had two stents placed. Overall improvement in pain, edema, and ulcers was reported in 147 (59%) of octogenarians and 24 (65%) of nonagenarians. There were no surgical site infections, pseudo-aneurysms, arteriovenous fistulas, or femoral artery injuries. No patients required transfusion within three days post-operatively and there were no 30-day mortalities in both sets of patients. Conclusions Our results demonstrate that there is no statistical difference in the outcome of performing venography, intravascular ultrasound, and stent placement in an office-based setting in octogenarians and nonagenarians. Both groups maintained a similar safety profile with low morbidity and mortality. In conclusion, we believe that the treatment of non-thrombotic iliac vein lesion in an office-based setting is safe and efficacious in both groups.

Objective A quality improvement initiative was employed to decrease single institution surgical site infection rate in open lower extremity revascularization procedures.

OBJECTIVE:Endovenous thermal ablation has become the primary modality of treatment for patients with venous insufficiency. Previous literature has provided reviews of radiofrequency ablation (RFA) or endovenous laser ablation (EVLA) that mostly focus on the great saphenous vein (GSV) and small saphenous vein (SSV). Data with an extended review including the anterior accessory saphenous vein (ASV) and perforator veins (PVs) have been limited. This study examines the treatment of venous insufficiency with RFA and EVLA of these multiple veins to identify clinical and demographic predictors of both the early success and thrombotic complications of endovenous thermal ablation. METHODS:A retrospective analysis of patients who underwent either RFA or EVLA of the GSV, SSV, ASV, or PVs was performed from March 2012 through February 2014. The PVs were treated only using RFA. The success and complication rates of each method were compared. Procedure results were determined by duplex ultrasound examination at the next office visit. Obliteration of the target vein was defined as a success. A complication was defined as thrombosis of any vein proximal to the target vein or acute thrombosis of any tributaries. RESULTS:A total of 808 patients were treated with either RFA or EVLA (2057 procedures); 47 patients were excluded because of incomplete records. In total, 1811 procedures were included with an average of 2.4 procedures per patient. Excluding the PVs, the success rate of RFA was 98.4%, equivalent to EVLA at 98.1% (P = .66). The success rates of thermal ablation for each vein were as follows: GSV, 98.5%; SSV, 98.2%; ASV, 97.2%; and PVs, 82.4%. The overall thrombotic complication rate was 10.5%. The thrombotic complications include endovenous heat-induced thrombosis (EHIT; 5.9%) and acute superficial venous thrombosis (4.6%). However, when EHIT class 1 was excluded, the true EHIT rate was 1.16%. The rate of a thrombotic complication for each vein was as follows: GSV, 11.8%; SSV, 5.5%; ASV, 6.5%; and PVs, 2.4%. The thrombotic complication rate was 7.7% for RFA and 11.4% for EVLA (P = .007). Age, gender, laterality, presenting symptoms (based on Clinical, Etiology, Anatomy, and Pathophysiology class), and vein type and diameter have no effect on successful ablation. Increased vein diameter (P < .001) and type of vein (P < .0001) were significant predictors of acute thrombotic complications; however, on multivariable analysis, only type of vein was an independent statistically significant predictor when nested for within-person correlation. CONCLUSIONS:There were no statistical difference in successful closure rates between RFA and EVLA. The type of procedure (EVLA), larger vein diameters, and treatment of the GSV were associated with a greater thrombotic complication rate, but type of vein was the most significant independent predictor.

A 28-year-old Hispanic female with a history of deep vein thrombosis (DVT) presented to the emergency room with left lower extremity swelling and pain. On duplex venous examination, an extensive left lower extremity DVT extending to her left common iliac vein was identified. A perforator vein measuring 2.6 mm located in the midcalf area was used to access and perform mechanical and chemical thrombolysis. Complete resolution of symptoms was observed.

BACKGROUND:Routine radiofrequency ablation (RFA) of an incompetent perforator vein (IPV) using the standard treatment protocol at 85°C has a treatment time of 6 minutes. To make treatment time more efficient, we sought to determine the effect of a shortened protocol for radiofrequency stylet (RFS) ablation by comparing the early success using three different temperatures: 85°C, 90°C, and 95°C. METHODS:A retrospective study examined 642 procedures of IPV closures in 255 patients with varying degrees of venous insufficiency treated with RFA from 2009 to 2015. The Covidien (Mansfield, Mass) RFA system allows the operator to regulate temperature and allows increments in temperature of the RFS to 85°C, 90°C, and 95°C. The RFS probe was angled at four 90-degree angles at the mentioned temperatures with a shorter treatment time at 6, 4, and 3 minutes, respectively. The three different treatment protocols were compared. All patients had comparative preoperative and postoperative duplex ultrasound scans. Postoperative duplex ultrasound scans were performed 3 to 7 days after the procedure. Successful obliteration was defined as lack of color flow on postoperative duplex ultrasound scanning. Clinical correlation with age, gender, laterality, presenting symptoms (Clinical, Etiology, Anatomy, and Pathophysiology [CEAP] classification), location, and vein diameter was also performed. RESULTS:Of the 255 patients who underwent RFS ablation, 138 were female, with a mean age of 65 years (standard deviation, ±14.6 years). These patients had CEAP presentations from C1 to C6 (0 C1, 1 C2, 57 C3, 118 C4, 4 C5, 75 C6). The location of the 642 IPVs was distributed as 472 in the calf and 170 in the ankle; 322 of these procedures were performed on the right leg. Use of a shortened protocol had no significant effect on the early obliteration rates with the 85°C, 90°C, and 95°C protocols, which were 66.1%, 61.8%, and 67.1%, respectively. Significant correlation was seen between location of targeted vein and successful obliteration (P < .001). There was a borderline inverse linear association between higher stylet temperature and successful obliteration in the proximal calf at 85°C. After accounting for within-patient correlation, the middle and distal calf continued to show higher nonobliteration compared with the ankle. No clinical correlation with age, gender, laterality, presenting symptoms of CEAP, or vein diameter was observed. CONCLUSIONS:The study showed that shortening the protocol time for RFA of the perforator did not make a significant difference in the early success rate, regardless of the temperature. The overall early success rate is still low (65.1%). RFA of perforator veins has a higher successful closure rate in proximal calf and ankle areas compared with the middle and distal calf.