Advanced Endovascular Training for Vascular Residents: What More Do We Need?

In the 25 years that formalized vascular surgery training and certification has been, in effect, the treatment of patients with peripheral vascular disease has undergone dramatic changes, largely due to the emergence of a wide variety of endoluminal techniques and devices that enable minimally invasive treatment of conditions that formerly required operative intervention. Unfortunately, vascular surgeons, for the most part, were painfully slow to embrace these new and evolving technologies, which became increasingly complex as they expanded to treat virtually all vascular maladies in all peripheral vascular territories. Not surprisingly, this left vascular surgeons disadvantaged relative to other disciplines for whom these techniques were more familiar, and we have spent the better part of the last decade playing catch-up to master them and regain our role as the only specialty qualified to offer all types of therapies to our patients with vascular disease. This has caused some to question what changes need to be made in our vascular surgery training paradigm for our new trainees to attain and maintain a preeminent role in the evaluation and treatment of patients with peripheral vascular disease. While the knee-jerk response is to consider special or supplemental training programs for these advanced techniques, or even certificates of added qualifications for the more challenging of them, such as carotid stenting, we believe that all that is really needed is for the vascular surgical community as a whole, and particularly those faculty in training programs, to truly embrace these new technologies and apply them to the patients they are already rendering care to. Given the prevalence of vascular disease and overall wealth of clinical material already present in most training programs, the simple willingness to apply endoluminal therapies to our existing patient populations is all that would really be needed to insure that all future graduates of vascular surgery training programs are fully competent in all of the current endoluminal therapies and well-positioned to continue to evolve with the field. The real question to be considering, which is beyond the focus of this article, is how we are to maintain our open surgical skills in the era of minimally invasive treatment of vascular disease.

Establishment of a Varicose Vein Center in a Tertiary Vascular Surgery Practice: Urban Versus Rural Differences

We examined changes in practice patterns after the establishment of a varicose vein center (VVC) within two tertiary university vascular surgery practices and compared differences between urban (U) and rural (R) sites. Practice patterns for the treatment of VVs were compared 3 years before (period 1) and 3 years after (period 2) the formation of a U-VVC and an R-VVC in 2001. Both VVCs were part of similar-sized tertiary vascular surgery practices. Evaluation was specific to VVs, reticular veins, and telangiectasias. Prior to U-VVC, there were 338 office visits, six office procedures, and 114 hospital procedures. After U-VVC, there were 624, 120, and 312, respectively. Prior to R-VVC, there were 85 office visits, five office procedures, and 69 hospital procedures. After R-VVC, there were 528, 163, and 303, respectively. In period 1 for U-VVC and R-VVC, VVC relative value unit (RVU) generation as a percent of total practice RVUs was 1.0% and 0.7%, respectively. In period 2 for U-VVC and R-VVC, VVC RVU generation as a percent of total practice RVUs was 2.6% and 2.5%, respectively. In an effort to provide more coordinated treatment for patients with VVs, establishing a VVC within a tertiary academic vascular surgery practice can lead to rapid expansion of clinical volume by increased office visits, office procedures, and hospital procedures. Clinical demand for evaluation and treatment of VVs showed little variation between R-VVC and U-VVC.

Closure of a surgically created arteriovenous fistula with a covered stent-graft in a patient with venous ambulatory hypertension--a case report

The purpose of this paper is to report the use of a covered stent-graft in the endovascular treatment of a surgically created arteriovenous fistula. A 37-year-old woman with symptomatic venous ambulatory hypertension underwent a left common femoral vein-to-right common iliac vein bypass using 10 mm ringed polytetrafluoroethylene (PTFE) with creation of an arteriovenous (AV) fistula from the superficial femoral artery to the PTFE graft. At 1 year postoperatively, recurrent symptoms thought to be due to the arteriovenous fistula were treated by placement of an 8 mm x 10 cm Viabahn covered stent-graft. Placement was via crossover technique from the right common femoral artery using a 9 French sheath. At 2 months' follow-up symptoms had resolved, the AV fistula was occluded, and venous bypass remained patent. Focal arteriovenous fistulas of the proximal superficial femoral artery can be treated safely with a covered stent-graft via an endovascular approach.

The inaccuracy of simple visual interpretation for measurement of carotid stenosis by arteriography

PURPOSE

To determine intraobserver and interobserver variability of carotid arteriography interpretation as well as the reliability of simple visual interpretation (SVI) or "eyeballing" of arteriography in the measurement of internal carotid artery stenoses.

METHODS

Intraobserver and interobserver measurements of 200 carotid arteriograms were performed in a blinded fashion by two vascular surgeons (VS1 and VS2) using a digital caliber computer program similar to software available in catheterization laboratories. The distal normal internal carotid artery was used as a frame of reference. These computer-derived measurements were compared with previous SVI measurements, found by retrospective chart review, that were performed at the initial time of arteriography.

RESULTS

Intraobserver agreement (VS1a vs VS1b and VS2a vs VS2b) within +/-5% using the computer program was 94% and 92%. Interobserver agreement within +/-5% using the computer program for the four possible combinations ranged from 43% to 48%. Interobserver agreement using the computer program increased to 83% to 88% for correct stenosis interpretation within +/-20%. In the 16% to 49% category (by computer measurement), SVI would have placed the stenosis in a higher category 40% to 56% of the time. Likewise, in the 50% to 79% category, comparing SVI with the four different computer caliber measurements, SVI overestimated the stenosis to the 80% to 99% category by 30% to 44%. In the 80% to 99% category, SVI overestimated lesions in 27% to 51% of the cases. All occlusions seen on SVI correlated with computer program measurements. The computer readings in many cases downgraded the degree of carotid stenosis into a lower category and in some cases, may have led to a different treatment paradigm. SVI never underestimated carotid stenosis compared with all matched computer program measurements.

CONCLUSIONS

Compared with a method of objective measurement similar to that used in a catheterization laboratory, SVI overestimated most carotid artery stenoses. Given the coming era of carotid stenting and a renewed need for arteriography before carotid intervention, knowledge of variability and correct interpretation of carotid stenosis using available technology remains paramount to warranted treatment.

Anesthesia Technique and Outcomes of Endovascular Aneurysm Repair

Anesthetic techniques vary widely in the endovascular repair of abdominal aortic aneurysms (EVAR). Previous studies have demonstrated the feasibility of using local anesthesia. However, the ideal anesthetic technique has not been determined. This study examines whether anesthetic technique influences the outcomes of EVAR. Data regarding demographics, risk factors, procedural characteristics, recovery characteristics, treatment complications, acute (<30 day) medical complications, mortality, and anesthetic type were prospectively collected during the AneuRx phase II aortic endograft trial. Patient cohorts receiving general, regional, or local anesthesia were compared. From 1997 to 1998, 424 patients underwent EVAR at 13 sites using the AneuRx Bifurcated endograft. There were 279 patients in the general anesthesia group, 95 patients in the regional group, and 50 patients in the local group. Risk factors were similar. There were no significant differences in age, gender, American Society of Anesthesiologists grade, length of anesthesia, branch artery occlusions, proximal endoleaks, failed implants, or open surgical conversions. Cardiac, renal, and wound-healing complications were all lower in the local group. Mortality was equivalent among the three groups. (p > 0.05, ANOVA). From these results we concluded that EVAR with local anesthesia is a safe and efficacious method that may reduce recovery times and postoperative medical morbidity compared to use of general or spinal/epidural anesthesia.

Predictors of complications after a prospective evaluation of diagnostic and therapeutic endovascular procedures

OBJECTIVE

To prospectively evaluate complications after diagnostic and therapeutic endovascular procedures (DTEPs) and determine what factors are predictive.

METHODS

From December 2002 to December 2003, all patients undergoing DTEPs performed by university vascular surgeons in a catheterization laboratory were prospectively evaluated. Medical demographics, procedure-related details, and type and severity of complications were recorded at the time of the procedure, during the first 24 hours, and at 2 to 4 weeks. Complications were classified as local vascular (LV), local nonvascular (LNV), systemic remote (SR), and major, minor, and nonsignificant.

RESULTS

Three hundred-three DTEPs were performed (54.5% DEPs, 45.5% TEPs). At the time of DTEP, 28 complications occurred in 23 patients: 10 LV (3.3%), 15 LNV (5.0%), and 3 SR (1.0%). At 24 hours, 26 complications occurred in 25 patients: 5 LV (1.7%), 7 LNV (2.3%), and 14 SR (4.7%). At 2 to 4 weeks, 26 complications occurred 25 patients: 5 LV (1.7%), 7 LNV (2.3%), and 14 SR (4.7%). The combined major (7.3%) and minor (4.3%) complication rate attributed to DTEPs was 11.6%. Significant predictors (P < .05) by multivariate analysis included thrombolysis, prior stroke, an additional procedure during the study period, and diabetes mellitus (odds ratios: 9.1, 3.2, 2.7, and 2.4, respectively).

CONCLUSION

According to newly applied reporting standards, the prospective evaluation of DTEPs reveals that complications are uniformly distributed by type and follow-up period. Just over 1 in 10 patients will suffer either a major or minor complication. Potential predictors have been identified that may assist in patient selection and treatment plans to lower complications resulting from DTEPs.

Thrombolysis and mechanical thrombectomy for arterial disease

Thrombolytic therapy has been around for close to 30 years now,but its exact role in the treatment of acute and chronic arterial occlusive disease continues to be debated. Studies have produced varying and contradictory results. We are still not sure if thrombolysis has any true advantages over surgical thromboembolectomy,or which lytic agent is the best. Nonetheless, the technique still plays an important role in the treatment of arterial occlusions.

Characterization and Probability of Upper Extremity Deep Venous Thrombosis

The objective of this study was to characterize patient demographics, risk factors, and anatomic distribution of upper extremity deep venous thrombosis (UEDVT) to develop a probability model for diagnosis. A retrospective review of all patients who underwent color-flow duplex scanning (CDS) for clinically suspected acute UEDVT over a 5-year period was performed. Patient risk factors and clinical symptoms were evaluated as predictors. Technically adequate complete CDS of 177 upper extremities (UEs) of arms were reviewed. CDS scanning identified acute UE venous thrombosis in 53 (30%) of the arms examined with deep system involvement in 40 (23%). Of the UEs affected, the subclavian was involved in 64%, the axillary in 25%, the internal jugular in 32%, the brachial in 36%, the cephalic in 32%, and the basilic in 47%. Multivariate analysis identified limb tenderness (odds ratio 9.3), history of central venous catheterization (odds ratio 7.0), and malignancy (odds ratio 2.9) as positive predictors for UEDVT. Erythema (odds ratio 0.12) and suspected pulmonary embolism (odds ration 0.06) were identified as negative predictors. A predictive model was designed from these variables. The anatomic distribution of UEDVT obtained from this study is consistent with previous reviews. Potential positive and negative risk factors can be identified from which a predictive model can be designed. Use of this model can help focus clinical suspicion, improve color-flow duplex utilization, and provide timely treatment with anticoagulation.

The AneuRx modular endograft device for the treatment of abdominal aortic aneurysms. Overview of 7 years of clinical use

Open surgical repair of abdominal aortic aneurysms (AAAs) has been performed for over 40 years now with good results. However, the procedure continues to be high-risk with numerous potential complications. The AneuRx modular bifurcated endograft was one of the first to be tested to exclude AAAs via an endovascular approach. Data from multiple clinical trials show that treatment of AAAs with the AneuRx device is comparable to open repair with regards to mortality and may have improved short-term and long-term morbidities rates. The following review discusses clinical use of the AneuRx stent graft system from the initial clinical trial in 1996 to its current commercial use.

Pancreatitis Caused by Rheolytic Thrombolysis: An Unexpected Complication

Two patients developed acute pancreatitis after mechanical thrombolysis with use of the AngioJet system. Patient 1 had undergone a remote complex revascularization of the lower extremities and presented with acute ischemia after thrombosis of his composite distal bypass. Patient 2 presented with superior vena cava (SVC) syndrome and had thrombosis of the SVC and innominate veins. Despite dissimilar presentations, both patients had renal insufficiency, were treated with mechanical and chemical thrombolysis, and had extensive thrombus burden. The pathophysiology of acute pancreatitis in this setting is believed to be secondary to massive hemolysis in the presence of chronic renal insufficiency. This phenomenon should be considered in patients whom develop abdominal pain after mechanical thrombolysis.

Endograft infection leading to rupture of aortic aneurysm

Aortic endografting has quickly been accepted as a less morbid method of aneurysm repair. However, preservation of the aortic sac after endografting remains a liability of this procedure. Late rupture has occurred, albeit rarely. Graft infections are another rare complication of endografting. We present the first reported case, to our knowledge, of aortic rupture secondary to infection of an aortic endograft.

Essentials of endovascular surgery training: how to get started in carotid stenting

Although early on vascular surgeons rebuked the concept that carotid stenting could stand up against the gold standard of carotid endarterectomy, this minimally invasive treatment for carotid bifurcation disease has been shown to have surprisingly low rates of periprocedural complications and is clearly favored by patients, for whom avoidance of surgery reigns paramount. Unfortunately, reluctance to embrace this and other emerging endovascular technologies, as well as a variety of other factors to be discussed, has left vascular surgeons poorly positioned to participate in the delivery of these therapies to their patients. With estimates of up to 75% of carotid stenoses being suitable for treatment by this new modality, and with carotid endarterectomy being the most commonly performed vascular operation in the United States today, this is a significant problem for our specialty and one badly in need of a solution. An understanding of the myriad of underlying interrelated problems helps to provide insight into possible solutions.

Selective venography versus nonselective venography before vena cava filter placement: evidence for more, not less

OBJECTIVE

We undertook this study to determine whether additional use of selective venography, compared with nonselective venography alone, reveals more abnormal anatomic venous findings that lead to changes in vena cava filter (VCF) position.

METHODS

From January 1998 to June 2002, 94 patients underwent VCF placement by vascular surgeons at a university tertiary care center. Indications, techniques, decision analysis, and complications were reviewed. Nonselective venography and selective venography of the inferior vena cava (IVC) were evaluated for image quality, abnormal findings, aberrant anatomy, and the anatomic relationship of vertebral bodies to major venous tributaries.

RESULTS

Absolute and relative indications for VCF placement were 44% and 56%, respectively. Jugular, femoral, and subclavian vein approach was used in 47%, 47%, and 6% of patients, respectively. Seventy-three percent of VCFs were placed in the catheterization laboratory, 21% in the operating room, and 5% at the bedside. Nonselective venography was performed in 80 patients (85%), of whom 44% had undergone selective venography. At nonselective venography plus selective venography 7.5% of patients had an abnormal finding (IVC compression, n = 3; IVC thrombus, n = 2; tortuosity, n = 1). Similarly, 17.5% of patients had aberrant anatomy (accessory renal vein, n = 8; IVC duplication, n = 3; large low right gonadal vein, n = 2; megacava, n = 2). Nonselective venography plus selective venography demonstrated that 16% of VCFs required a major change in position, 10% of which were placed above the renal veins. Compared with nonselective venography alone, selective venography enabled detection of significantly more abnormal and aberrant findings (9% vs 49%; P <.001). Changes in VCF placement were necessary significantly more often in patients undergoing additional selective venography compared with nonselective venography alone (31% vs 4%; P =.003). In one patient in the series, a VCF was malpositioned in the iliac vein with intravascular ultrasound visualization.

CONCLUSION

When nonselective venography plus selective venography were performed, 23% of patients had either an abnormal finding or aberrant anatomy, and most of these required a major change in VCF position. Nonselective venography plus selective venography redefines the criterion standard and, because of limitations of other methods of vena cava visualization for VCF deployment, should be performed in most patients.

Retrograde endovascular hypogastric artery preservation (REHAP) and aortouniiliac (AUI) endografting in the management of complex aortoiliac aneurysms

The preservation of internal iliac artery (IIA) flow during endovascular repair of abdominal aortic aneurysms (er-AAA) remains a controversial area. Ectasia and aneurysmal disease of the iliac arteries represent a formidable challenge to the endovascular surgeon, particularly when aortic neck length and diameter are suitable for er-AAA. We describe a procedure to maintain arterial perfusion to the pelvis during er-AAA called retrograde endovascular hypogastric artery preservation (REHAP). This technique is particularly useful in the presence of common iliac artery (CIA) and internal iliac artery (IIA) aneurysms when pelvic perfusion to one IIA needs to be maintained. A Wallgraft is first placed from the IIA to the ipsilateral EIA followed by er-AAA using an aortouniiliac graft (AUI) and a femorofemoral bypass graft (BPG). This procedure represents one alternative to maintaining pelvic perfusion using standard endovascular and surgical techniques.

Indications and outcomes of AneuRx Phase III trial versus use of commercial AneuRx stent graft

OBJECTIVE

Approval by the United States Food and Drug Administration of endoluminal repair of abdominal aortic aneurysm (AAA) with the AneuRx stent graft was based on the outcome of a multicenter trial in which patients met strict inclusion and exclusion criteria. Since widespread use of the commercially available graft, little information is available as to whether indications and outcomes have evolved. We examined this important issue at our institution.

METHODS

Data concerning indications, repair, and follow-up for all patients undergoing endoluminal repair of AAA was prospectively entered into a patient registry. Group 1 comprised consecutive patients enrolled in the AneuRx Phase III clinical trial between November 1998 and September 2000. Group 2 consisted of consecutive patients who underwent implantation of the commercially available AneuRx graft between May 1999 and June 2001.

RESULTS

Group 1 included 42 patients (mean age, 72 years), and group 2 included 54 patients (mean age, 73 years). Patient demographics and risk factors were similar between the two groups. Maximum aortic aneurysm diameter was significantly greater (P =.021) in group 1 (55 mm +/- 10.9 [SD] mm) compared with group 2 (52 +/- 15.6 mm). Maximum infrarenal aortic neck length was significantly longer (P =.022) in group 1 (30 +/- 11.7 mm) than in group 2 (23 +/- 12.0 mm). Maximum left common iliac artery diameter in group 1 (13.0 +/- 3.2 mm) was significantly smaller (P =.032) than that in group 2 (14 +/- 6.5 mm). During follow-up, no differences were observed for number of endoleaks, subsequent interventions, or graft explantation between the two groups.

CONCLUSIONS

In group 2 patients AAAs were significantly smaller, infrarenal aortic neck length was shorter, and left common iliac arteries were larger. Common iliac artery ectasia and aneurysmal disease has become another indication for use of the AneuRx commercial graft at our institution, with no significant differences in intermediate outcome. Given the possibility for evolving indications compared with trial inclusion and exclusion criteria, institutions that use the AneuRx commercial graft should prospectively monitor outcomes for quality assurance.

Treatment of type III endoleak with an aortouniiliac stent graft

The purpose of this study was to present a novel treatment method for repair of a type III endoleak due to separation of modular components of an AneuRx (Medtronic AVE, Sunnyvalle, CA) stent graft as a result of graft kinking. A 73-year-old male had undergone endovascular repair of a 8.2-cm abdominal aortic aneurysm (AAA) 2 years previously. An aortic extender cuff was required to secure the proximal graft. Computed tomographic (CT) follow-up revealed a type III endoleak at 6-month follow-up. Plain radiographs showed separation between the main graft body and the aortic extender cuff. A second custom-made 28 mm x 5.5 cm aortic extender cuff was placed to seal the type III endoleak. Follow-up CT showed a persistent endoleak with an increase in AAA size to 10.5 cm. The patient underwent remedial AAA repair with an aortouniiliac endograft placed within the previous stent graft and a femorofemoral bypass. At 3-month follow-up there was no detectable endoleak. This constitutes an alternative endovascular therapy for modular device separation (type-III endoleak) after endoluminal AAA repair in patients who cannot undergo repair with a second bifurcated graft.

Outcome of catheter-directed thrombolysis for lower extremity arterial bypass occlusion

OBJECTIVE

The purpose of this study was to determine the clinical outcome of patients undergoing catheter-directed thrombolysis (CDT) for lower extremity arterial bypass (LEAB) occlusion.

METHODS

A retrospective review was performed of two university-based practices from 1988 to 2001. All patients with LEAB occlusion (<14 days by history) undergoing CDT as initial treatment were included. Technical success, complications, secondary patency, and limb salvage were examined. Additional analysis examined secondary procedures performed for residual lesions or failed CDT and the number of LEABs that were replaced or that became infected.

RESULTS

One hundred four patients (77% male; mean age, 65 years) had 109 LEAB occlusions. CDT restored patency in 77%. Of the 25 LEABs that failed initial CDT, 15 underwent surgical thrombectomy/revision, four were replaced, and six underwent no further interventions. Of the 84 LEABs successfully lysed, 51 had residual lesions that underwent revision with interventional (n = 30) or surgical (n = 15) techniques or both (n = 6). Median hospital stay was 8 days with three periprocedural deaths. One quarter of CDT procedures had bleeding or thrombotic complications or both. The mean follow-up period was 45 months. Secondary patency rates on an intention-to-treat basis (attempted thrombolysis) were 32% and 19% at 1 and 5 years, respectively. After successful CDT, the 1-year secondary patency rate was comparable in LEABs with or without residual lesions (42% versus 45%). Overall, the limb salvage rates were 73% and 55% at 1 and 5 years, respectively. The survival rate was 56% at 5 years. Ten of the 54 LEABs (19%) that eventually failed after successful CDT had three or more reocclusive episodes. Seven LEABs (8.3%) salvaged with CDT eventually became infected from recurrent interventions; six of these necessitated major amputation. Twenty LEABs initially salvaged with CDT were replaced (four immediately and 16 after episodes of recurrent ischemia). Two patients died during hospitalization for treatment of recurrent ischemia.

CONCLUSION

Despite relatively high initial technical success for LEAB thrombolysis, eventual failure is the rule rather than the exception. Recurrent LEAB occlusions lead to significant morbidity, including recurrent interventions, eventual graft infection/replacement, and limb loss. However, LEAB replacement has substantial problems associated with limited conduit, reoperative anatomy, and subsequent wound complications. We therefore advocate an initial attempt at CDT with liberal use of graft replacement for early and late failures or as an initial strategy in those with favorable remaining conduit.