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Mark A Farber

Publications and source records attributed to Mark A Farber.

12 recordsLinked to original sources
PubMed2007

Coverage of the left subclavian artery during thoracic endovascular aortic repair.

BACKGROUND: Thoracic aortic stent grafts require proximal and distal landing zones of adequate length to effectively exclude thoracic aortic lesions. The origins of the left subclavian artery and other aortic arch branch vessels often impose limitations on the proximal landing zone, thereby disallowing endovascular repair of more proximal thoracic lesions. METHODS: Between October 2000 and November 2005, 112 patients received stent grafts to treat lesions involving the thoracic aorta. The proximal aspect of the stent graft partially or totally occluded the origin of at least one great vessel in 28 patients (25%). The proximal attachment site was in zone 0 in one patient (3.6%), zone 1 in three patients (10.7%), and zone 2 in 24 patients (85.7%). Patients with proximal implantation in zones 0 or 1 underwent debranching procedures of the supra-aortic vessels before stent graft repair. In one patient who underwent zone 1 deployment, the left subclavian artery was revascularized before stent graft deployment. Among patients who underwent zone 2 deployment with partial or complete occlusion of the left subclavian artery, none underwent prior revascularization. Patients were assessed postoperatively and at follow-up for development of neurologic symptoms as well as symptoms of left upper extremity claudication or ischemia. RESULTS: Mean follow-up was 7.3 months. Among the 24 patients with zone 2 implantation, 10 (42%) had partial left subclavian artery coverage at the time of their primary procedure. A total of 19 patients experienced complete cessation of antegrade flow through the origin of the left subclavian artery without revascularization at the time of the initial endograft repair as a result of a secondary procedure or as a consequence of left subclavian artery thrombosis. Left upper extremity symptoms developed in three (15.8%) patients that did not warrant intervention, and rest pain developed in one (5.3%), which was treated with the deployment of a left subclavian artery stent. Two primary (type IA and type III) endoleaks (7.1%) and one secondary endoleak (type IA) (3.6%) were observed in patients who underwent zone 2 deployment. Three cerebrovascular accidents were observed. Thoracic aortic lesions were successfully excluded in all patients who underwent supra-aortic debranching procedures. CONCLUSION: Intentional coverage of the origin of the left subclavian artery to obtain an adequate proximal landing zone during endovascular repair of thoracic aortic lesions is well tolerated and may be managed expectantly, with some exceptions.

Adolescent↗
PubMed2006

Natural history of limbs with arterial insufficiency and chronic ulceration treated without revascularization.

OBJECTIVES: The natural history of limbs affected by ischemic ulceration is poorly understood. In this report, we describe the outcome of limbs with stable chronic leg ulcers and arterial insufficiency that were treated with wound-healing techniques in patients who were not candidates for revascularization. METHODS: A prospectively maintained database of limb ulcers treated at a comprehensive wound center was used to identify patients with arterial insufficiency, defined as an ankle-brachial index (ABI) <0.7 or a toe pressure <50 mm Hg. Patients were treated without revascularization when medical comorbidity or anatomic considerations did not allow revascularization with acceptable risk. Ulcers were treated with a protocol emphasizing pressure relief, débridement, infection control, and moist wound healing. Risk factors analyzed for their affect on healing and amputation risk included age, gender, diabetes mellitus, chronic renal insufficiency (serum creatinine > 2.5 mg/dL), severity of ischemia measured by ABI or toe pressure, wound grade, wound size, and wound location. RESULTS: Between January 1999 and March 2005, 142 patients with 169 limbs having arterial insufficiency and full-thickness ulceration were treated without revascularization. Mean patient age was 70.8 +/- 4.5. Diabetes mellitus was present in 70.4% of limbs and chronic renal insufficiency in 27.8%. Toe amputations or other foot-sparing procedures were performed in 28% of limbs. Overall, limb loss occurred in 37 patients. By life-table analysis, 19% of limbs required amputation < or =6 months of initial treatment and 23% at 12 months. Complete wound closure was achieved in 25% by 6 months and in 52% by 12 months. Statistical analysis showed a correlation between ABI and the risk of limb loss. In patients with an ABI <0.5, 28% and 34% of limbs experienced limb loss at 6 and 12 months, respectively, compared with 10% and 15% of limbs in patients with an ABI >0.5 (P = .01). The only risk factor associated with wound closure was initial wound size (P < .005). CONCLUSIONS: Limb salvage can be achieved in most patients with arterial insufficiency and uncomplicated chronic nonhealing limb ulcers using a program of wound management without revascularization. Healing proceeds slowly, however, requiring more than a year in many cases. Patients with an ABI <0.5 are more likely to require amputation. Interventions designed to improve outcomes in critical limb ischemia should stratify outcomes based on hemodynamic data and should include a comparative control group given the natural history of ischemic ulcers treated in a dedicated wound program.

Adult↗
PubMed2006

Effect of challenging neck anatomy on mid-term migration rates in AneuRx endografts.

OBJECTIVE: To establish the effect of challenging neck anatomy on the mid- and long-term incidence of migration with the AneuRx bifurcated device in patients treated after Food and Drug Administration approval and to identify the predictive factors for device migration. METHODS: Prospectively maintained databases at the University of North Carolina (UNC) and Washington University (WU) were used to identify 595 patients (UNC, n = 230; WU, n = 365) who underwent endovascular repair of an infrarenal abdominal aortic aneurysm with the AneuRx bifurcated stent graft. Those patients with at least 30 months of follow-up were identified and underwent further assessment of migration (UNC, n = 25; WU, n = 59) by use of multiplanar reconstructed computed tomographic scans. RESULTS: Eighty-four patients with a mean follow-up time of 40.3 months (range, 30-55 months) were studied. Seventy percent of the patients (n = 59) met all inclusion criteria for neck anatomy (length, angle, diameter, and quality) as defined by the revised instructions for use guidelines and are referred to as those with favorable neck anatomy (FNA). The remaining 25 patients retrospectively fell outside of the revised instructions for use guidelines and are referred to as those with unfavorable neck anatomy (UFNA). Life-table analysis for FNA patients at 2 and 4 years revealed a migration rate of 0% and 6.1%, respectively. For UFNA patients, it was 24.0% and 42.1% at 2 and 4 years, respectively (P < .0001). The overall (FNA and UFNA) migration rate was 7.1% and 17.1% at 2 and 4 years, respectively. Overall, late graft-related complications occurred in 38% of patients (FNA, 27%; UFNA, 64%; P = .003; relative risk, 1.7). There was no incidence of late rupture or open conversion. The relative risk of migration for UFNA patients was 2.5 compared with FNA patients (P = .0003). A larger neck angle and a longer initial graft to renal artery distance were predictors of migration, whereas shorter neck length approached but did not reach statistical significance. CONCLUSIONS: Patients who have unfavorable aneurysm neck anatomy experience significantly higher migration, device-related complication, and secondary intervention rates. However, there was no incidence of open conversion, rupture, or abdominal aortic aneurysm-related death, thereby supporting the AneuRx device as a feasible alternative to open repair even in patients with challenging neck characteristics. Enhanced surveillance should be used in these high-risk patients.

Aged↗
PubMed2005

Endovascular repair of nontraumatic ruptured thoracic aortic pathologies.

Endovascular repair of ruptured infrarenal abdominal aortic aneurysms (AAA) is receiving increased attention as the number of experienced users increases. Development of thoracic aortic stent grafts has lagged behind infrarenal advancements because of the reported prevalence of disease. In a few centers, however, the experience in performing thoracic stent graft procedures is quite substantial, such that endovascular therapy has been applied to ruptured thoracic aortic pathologies even though data remain limited and this novel therapy remains controversial. We report our combined experience with endovascular repair of ruptured thoracic aneurysms (RTA) and ruptured thoracic dissections (RTD). One hundred eighty-four thoracic stent graft procedures at the University of North Carolina (UNC) and Union Memorial Hospital (UMH) were reviewed and those patients undergoing RTA or RTD repair from January 1, 2000 to December 31, 2003 identified. Patients having procedures for elective repair or aortic transections were excluded from the analysis. Patient presentation, preoperative condition, procedural variables, mortality, and morbidity were examined. Seventy-four percent of the collective procedures were undertaken in high-risk patients (UNC, 38 of 40; UMH, 99 of 144). Twenty-two patients (8.7%; UNC, n = 6; UMH, n = 16) underwent treatment for either an RTA (n = 11) or an RTD (n = 11). The average age of this cohort was 66.5 +/- 15.6 years and the average aneurysm diameter was 73.1 +/- 31.4 mm. The mean duration of symptoms prior to repair was 103.1 +/- 122 hr, influenced primarily by transport times and device availability. Stent graft exclusion was accomplished in 100% of patients with a procedural mortality of 0%. Commercial Talent devices were used in 19 patients (86.4%) and AneuRx device was used in 1 patient (4.5%). In the remaining two (9.1%) patients hand-made devices constructed of Gianturco stents and Dacron fabric were used because of active hemorrhage and lack of appropriate device sizes. Operative time was 135.5 +/- 48.5 min and was associated with an average blood loss of 242.0 +/- 232.4 cc. Thirty-day mortality was 45.5% (RTA, 27.3%; RTD, 63.6%; p = 0.099). Length of stay in the intensive care unit was 6.1 +/- 7.9 days and the mean hospital stay was 11.7 +/- 10.6 days. Major complications were present in 54.5% of RTA (cardiac, 1; pulmonary, 3; cardiovascular accident, 2; spinal cord ischemia, 2; pulmonary embolism, 1), and 81.2% of RTD (multisystem organ failure, 7; pulmonary, 1; common femoral artery injury, 1) but not statistically different between groups. There were only two late complications (cardiac death, endoleak-Ia, 1) that occurred during the mean follow-up of 12.5 +/- 11.3 (range, 1-32) months. These results indicate that endovascular repair of ruptured thoracic pathologies can be accomplished with an acceptable morbidity and mortality. There were no immediate procedural mortalities and complete exclusion was accomplished in all patients. Most postoperative complications arose from preexisting medical conditions and were not procedure related. The benefit of endovascular repair of ruptured thoracic aortic pathologies is promising.

Aged↗
PubMed2005

Endovascular stent-graft repair of pararenal and type IV thoracoabdominal aortic aneurysms with adjunctive visceral reconstruction.

OBJECTIVE: Pararenal and type IV thoracoabdominal aortic aneurysms (TAAA) are not currently considered as indications for endovascular repair given unfavorable neck anatomy or aneurysm involvement of the visceral vessels. Open repair of these aneurysms is associated with significant morbidity and mortality, particularly postoperative renal dysfunction. In selective high-risk patients, debranching of the visceral aorta to improve the proximal neck region can be used to facilitate endovascular exclusion of the aneurysm. METHODS: Between October 2000 and July 2003, 10 patients were treated with open visceral revascularization and endovascular repair of pararenal and type IV TAAAs at a single institution. Patient demographics and procedural characteristics were obtained from medical records. RESULTS: Overall 13 visceral bypasses were performed in 10 patients: 6 patients with a single iliorenal bypass, 3 with a hepatorenal bypass, and 1 patient with complete visceral revascularization. Juxtarenal aneurysms occurred in 5 patients (50%), suprarenal aneurysms in 3 patients (30%), and type IV TAAAs in 2 patients (20%). All patients had successful endovascular aneurysm exclusion. Mean follow-up was 8.7 months. There were no perioperative deaths, neurologic deficits coagulopathies, or renal dysfunction. Follow-up spiral computed tomography scans demonstrated patency of all bypass grafts with only one patient requiring a secondary intervention for late type I leak which was sealed with placement of a proximal cuff. CONCLUSION: These initial results suggest that are similar to infrarenal AAA endovascular repair. This combined approach to repair of pararenal and type IV TAAAs reduces the morbidity and mortality of open repair, and represents an attractive option in high-risk patients while endoluminal technology continues to evolve.

Aged↗
PubMed2005

Endovascular repair of lesions involving the descending thoracic aorta.

BACKGROUND: Vascular lesions involving the thoracic aorta are often life-threatening conditions that carry significant morbidity and mortality with traditional open surgical repair. Preliminary results suggest that endovascular therapy is an effective and possibly advantageous treatment for diseases of the descending thoracic aorta. METHODS: Between October 2000 and May 2004, 50 consecutive patients underwent endovascular stent-grafting of lesions involving the descending thoracic aorta. Attempted stent-graft deployment was performed electively in 39 patients and emergently in 11. The pathology of electively treated aortic lesions included degenerative/atherosclerotic aneurysms (n = 24), pseudoaneurysms (n = 11), aortic dissections (n = 2), and penetrating ulcers (n = 2). Emergently treated aortic lesions were for acute rupture due to infectious (mycotic) aneurysms (n = 4), atherosclerotic/degenerative aneurysms (n = 3), acute type B dissections (n = 2), and acute transections (n = 2). Devices used include Talent (n = 45), AneuRx aortic cuffs (n = 2), custom-fabricated Gianturco-Dacron grafts (n = 2), and a modified Cook-Zenith abdominal aortic graft (n = 1). Follow-up was performed at 1-month, 6-months, 1-year, and annually thereafter. RESULTS: Primary technical success, defined as successful deployment and exclusion of the lesion without evidence of type I or type III endoleak, was achieved in 48 (96%) of 50 patients. In one patient, the procedure was terminated due to inability to access the iliac vessels. In another patient, a type III endoleak was observed at the completion of the primary procedure that required deployment of an additional stent-graft component 2 months later. Of the 49 patients who received endografts, seven underwent secondary procedures to correct endoleaks, with five of these seven requiring the deployment of additional endovascular stent-graft components. Major complications included four in-hospital deaths, with three of these occurring in patients treated emergently. Additionally, respiratory failure (n = 6), multisystem organ failure (n = 2), cerebrovascular accident (n = 2), retroperitoneal hematoma (n = 2), acute renal insufficiency (n = 1), and pulmonary embolus (n = 1) were also observed. The overall endoleak rate was 20%, with five primary (< or = 30 days) and five secondary (> 30 days) endoleaks observed. Five of the endoleaks were treated with the deployment of one or more additional endovascular stent-graft components. Two of the endoleaks were treated with endovascular balloon remolding. Mean follow-up was 271 days. There were no aneurysm ruptures or aneurysm-related deaths. CONCLUSIONS: Endovascular treatment of vascular lesions involving the descending thoracic aorta can be safely performed with low morbidity in high-risk patients. Endovascular repair may become an attractive alternative for the treatment of a wide range of pathology along this vascular territory.

Adult↗
PubMed2003

Treatment of superficial and perforator venous incompetence without deep venous insufficiency: is routine perforator ligation necessary?

PURPOSE: We investigated whether routine ligation of incompetent perforator veins is necessary in treatment of symptomatic chronic venous insufficiency (CVI) due to combined superficial and perforator vein incompetence, without deep venous insufficiency. METHODS: This was a retrospective review of prospectively collected data. Twenty-four limbs with both superficial and perforator venous incompetence but no deep venous insufficiency were identified at venous duplex scanning. Air plethysmography (APG) was performed preoperatively, to obtain venous volume (VV), venous filling index (VFI), ejection fraction (EF), and residual volume fraction (RVF) of the affected limb. Saphenous vein stripping from the groin to knee and powered transilluminated phlebectomy for varicosity ablation were performed in all patients. Postoperatively, all patients underwent duplex scanning and APG to determine the status of the perforator veins and hemodynamic improvement from surgery. RESULTS: Average patient age was 55.8 years; 62% of patients were women. CVI was class 3 in 4 limbs, class 4 in 12 limbs, and class 5 and class 6 in 4 limbs each. Postoperative duplex scans demonstrated that 71% of previously incompetent perforator vessels were now competent or absent. Significant improvement in all APG values was documented after superficial surgery. VFI improved from 6.0 +/- 2.9 preoperatively to 2.2 +/- 1.3 after surgery (P <.001); EF improved from 56.3 +/- 18 to 62 +/- 21 (P =.02); and RVF improved from 40.1 +/- 19 to 28.3 +/- 18 (P =.009). Mean preoperative symptom score (5.3 +/- 1.9) was significantly improved at mean follow-up of 18.3 months (1.4 +/- 1.2; P <.001). CONCLUSION: Patients with superficial and perforator vein incompetence and a normal deep venous system experienced significant improvement in APG-measured hemodynamic parameters and clinical symptom score after superficial ablative surgery alone. This suggests that ligation of the perforator veins can be reserved for patients with persistent incompetent perforator vessels, with abnormal hemodynamic parameters or continued symptoms after superficial ablative surgery.

Adult↗
PubMed2002

Recurrence of chronic venous ulcers on the basis of clinical, etiologic, anatomic, and pathophysiologic criteria and air plethysmography.

INTRODUCTION: Leg ulcers associated with chronic venous insufficiency (CVI) frequently recur after healing. The risk of recurrence has not been well defined for patients in different anatomic and hemodynamic groups. We reviewed the risk of ulcer recurrence on the basis of clinical, etiologic, anatomic, and pathophysiologic criteria and hemodynamic characteristics of the affected limb as assessed with air plethysmography (APG). METHODS: Ninety-nine limbs with class 6 CVI were assessed clinically and with standing duplex ultrasound scanning and APG for the definition of clinical, etiologic, anatomic, and pathophysiologic criteria. Leg ulcers were treated with high-pressure compression protocols. Surgical correction of venous abnormalities was offered to patients with appropriate conditions. After ulcer healing, the limbs were placed in compressive garments and followed at 6-month intervals for ulcer recurrence. RESULTS: The mean patient age was 54.3 years, and 46% of the patients were female. Corrective venous surgery was performed in 37 limbs. The mean follow-up time for all 99 limbs was 28 months. The ulcer recurrence rate with life table was 37% +/- 6% at 3 years and 48% +/- 10% at 5 years. The patients who underwent venous surgery had a significantly lower recurrence rate (27% +/- 9% at 48 months) than did those patients who had not undergone surgery (67% +/- 8% at 48 months; P =.005). The patients with deep venous insufficiency (DVI; n = 51) had significantly higher recurrence rates (66% +/- 8% at 48 months) than did the patients without DVI (n = 48; 29% +/- 9% at 48 months; P =.006). This difference was significant even after accounting for the effects of surgery (P =.03). The hazard ratio of ulcer recurrence increases by 14% for every unit increase in the venous filling index (VFI; P =.001). This remains significant even after accounting for the effects of surgery (P =.001). The combination of DVI and a VFI of more than 4 mL/s yields a risk of ulcer recurrence of 43% +/- 9% at 1 year and 60% +/- 10% at 2 years. CONCLUSION: Leg ulcers associated with CVI have a high rate of recurrence. Ulcer recurrence is significantly increased in patients with DVI and in patients who do not have venous abnormalities corrected surgically. The VFI obtained from APG is useful in the prediction of increased risk for recurrence, particularly in association with anatomic data.

Bandages↗
PubMed2002

Prediction of wrist arteriovenous fistula maturation with preoperative vein mapping with ultrasonography.

OBJECTIVE: The purpose of this study was to determine whether the preoperative minimal cephalic vein size in the forearm was predictive of successful wrist fistula maturation to a functional hemodialysis access. METHODS: Forty-four consecutive patients underwent evaluation before surgery with ultrasound scan imaging to map the entire cephalic vein in preparation for the construction of an arteriovenous fistula at the wrist. Measurements of the vein diameter were obtained from the ultrasound scan images at eight representative sites. Patients were clinically followed to determine maturation of the fistula to provide a functional hemodialysis access. The smallest diameter of the cephalic vein then was used as a preoperative predictor of fistula maturation. RESULTS: Successful maturation of the arteriovenous fistula was achieved in 22 of the procedures (50%). Cephalic veins with a minimal diameter of 2.0 mm or less were used for anastamosis in 19 patients (43%), and three of these procedures (16%) led to a functional access site. The remaining 25 patients (57%) had minimal cephalic vein diameters greater than 2.0 mm, producing a successful maturation in 19 of the fistula creations (76%). A significantly higher rate of successful fistula maturation in those patients with a preoperative minimal cephalic vein size greater than 2.0 mm was realized (P =.0002, chi(2) test, with Yates correction for continuity). CONCLUSION: In patients with a minimal cephalic vein size of 2.0 mm or less, a procedure other than wrist fistula should be considered for optimization of dialysis access.

Adolescent↗
PubMedDate not supplied

Endovenous saphenous ablation corrects the hemodynamic abnormality in patients with CEAP clinical class 3-6 CVI due to superficial reflux.

This investigation was designed to determine whether minimally invasive radiofrequency or laser ablation of the saphenous vein corrects the hemodynamic impact and clinical symptoms of chronic venous insufficiency (CVI) in CEAP clinical class 3-6 patients with superficial venous reflux. Patients with CEAP clinical class 3-6 CVI were evaluated with duplex ultrasound and air plethysmography (APG) to determine anatomic and hemodynamic venous abnormalities. Patients with an abnormal (>2 mL/second) venous filling index (VFI) and superficial venous reflux were included in this study. Saphenous ablation was performed utilizing radiofrequency (RF) or endovenous laser treatment (EVLT). Patients were reexamined within 3 months of ablation with duplex to determine anatomic success of the procedure, and with repeat APG to determine the degree of hemodynamic improvement. Venous clinical severity scores (VCSS) were determined before and after saphenous ablation. Eighty-nine limbs in 80 patients were treated with radiofrequency ablation (RFA) (n = 58), or EVLT (n = 31). The average age of patients was 55 years and 66% were women. There were no significant differences in preoperative characteristics between the groups treated with RFA or EVLT. Postoperatively, 86% of limbs demonstrated near total closure of the saphenous vein to within 5 cm of the saphenofemoral junction. Eight percent remained open for 5-10 cm from the junction, and 6% demonstrated minimal or no saphenous ablation. The VFI improved significantly after ablation in both the RF and EVLT groups. Postablation, 78% of the 89 limbs were normal, with a VFI <2 mL/second, and 17% were moderately abnormal, between 2 and 4 mL/second. VCSS scores (11.5 +/-4.5 preablation) decreased significantly after ablation to 4.4 +/-2.3. Minimally invasive saphenous ablation, using either RFA or EVLT, corrects or significantly improved the hemodynamic abnormality and clinical symptoms associated with superficial venous reflux in more than 90% of cases. These techniques are useful for treatment of patients with more severe clinical classes of superficial CVI.

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