Arterial dissection during peripheral vascular interventions

OBJECTIVE

Arterial dissection (AD) is a known complication of peripheral vascular interventions (PVIs), but its incidence and significance have not been well-characterized. This study examines AD in the Vascular Quality Initiative database for patients treated for peripheral arterial disease. Our hypothesis is that AD is associated with decreased patency and worse limb outcomes.

METHODS

The Vascular Quality Initiative PVI registry (2016-2021) was reviewed. Patients were divided based on the presence or absence of reported AD during the procedure. Trend of incidence and management of AD was derived. The characteristics and outcomes of patients with and without AD were compared. The primary endpoint was primary patency.

RESULTS

There was a total of 177,790 cases, and 3% had AD. The incidence of AD significantly increased over the study period from 2.4% to 3.6% (P = .007). Endovascular therapy was used to treat AD in 83.7% of cases, 14.5% were treated medically, and only 1.8% required open surgery. Patients with AD were significantly more likely to be female (47.4% vs 39.7%; P < .001). Patient with AD were more likely to have a history of smoking (79.7% vs 77.2%; P < .001), but were significantly less likely to be on dialysis (8.2% vs 9.3%; P < .001) compared with patients without AD. Patients with AD were more likely to have femoropopliteal disease (45.2% vs 38.0%; P < .001) and undergo treatment of more complex disease as denoted by higher mean number of lesions treated (1.95 ± 1.01 vs 1.71 ± 0.89; P < .001), longer occlusion length (8 ± 16 vs 7 ± 15 cm; P < .001), and more severe TransAtlantic Inter-Society Consensus grade (Grade D: 36.2% vs 29.1%; P < .001). The proportion of stenting as a treatment modality was higher in the dissection group (55.4% vs 41.1%; P < .001). After a mean follow-up of 828 days, patients with AD had significantly lower primary patency than patients without AD. Kaplan-Meier curves demonstrated that the AD group had lower primary patency (86.9% vs 91%; P < .001) and reintervention-free survival (79.5 % vs 84.1%; P < .001) at 1 year with difference in amputation-free survival. Cox proportional hazard regression confirmed the independent association of AD with primary patency and reintervention-free survival.

CONCLUSIONS

AD is more common in women and is more likely to occur during treatment of the femoropopliteal segment. AD is associated with decreased primary patency and reintervention-free survival after PVI for peripheral arterial disease.

Effect of inferior vena cava filter placement position on device complications

BACKGROUND

Indwelling inferior vena cava (IVC) filters can cause complications, including penetration into surrounding structures, migration, and thrombosis of the vena cava. Computational fluid dynamics suggests juxtarenal placement of IVC filters decreases the risk of thrombosis; however, this has not been explored clinically. The present study examines the effect of filter placement position on long-term device complications with an emphasis on IVC thrombosis. We hypothesized that IVC filters placed further caudal to the renal veins were more likely to develop long-term thrombosis.

METHODS

A retrospective review of the medical records of patients receiving IVC filters at a single tertiary center between 2008 and 2016 was performed. Patients missing follow-up or procedural imaging data were excluded. The placement procedure venograms were reviewed, and the distance from the filter apex to the more inferior renal vein was measured using reported IVC filter lengths for calibration. The patients were divided into three groups according to the tip position relative to the more inferior renal vein: at or superior (group A), 1 to 20 mm inferior (group B), and >20 mm inferior (group C). The patient and procedural characteristics and outcomes were compared between the three groups. The primary end points were IVC thrombosis and device-related mortality.

RESULTS

Of 1497 eligible patients, 267 (17.8%) were excluded. The most common placement position was group B (64.0%). The mean age was lowest in group C, followed by groups A and B (age, 59.5 years, 64.6 years, and 62.2 years, respectively; P = .003). No statistically significant differences were found in the distribution of sex or the measured comorbidities. Group C was the most likely to receive jugular access (group C, 71.7%; group A, 48.3%; group B, 62.4%; P < .001) and received more first-generation filters (group C, 58.5%; group A, 46.6%; group B, 52.5%; P = .045). The short-term (<30-day) and long-term (≥30-day) outcomes, including access site hematoma, deep vein thrombosis, and pulmonary embolism, were uncommon, with no differences between the groups. Cases of symptomatic filter penetration, migration, and fracture were rare (one, one, and three cases, respectively). Although a pattern of increasing thrombosis with more inferior placement was found, the difference between groups was not statistically significant (group A, 1.5%; group B, 1.8%; group C, 2.5%; P = .638). No cases of device-related mortality occurred. All-cause mortality after a mean follow-up of 2.6 ± 2.3 years was 41.3% and did not vary significantly between the groups (P = .051). Multivariate logistic regression revealed that placement position did not predict for short- or long-term deep vein thrombosis, pulmonary embolism, IVC thrombosis, or all-cause mortality after adjustment for the baseline patient characteristics.

CONCLUSIONS

IVC filters have low rates of short- and long-term complications, including IVC thrombosis. The placement position did not affect the occurrence of device complications in this study.

Development of an international glossary for clinical guidelines collaboration

OBJECTIVES

Clinical practice guidelines (CPGs) are often created through collaboration among organizations. The use of inconsistent terminology may cause poor communication and delays. This study aimed to develop a glossary of terms related to collaboration in guideline development.

STUDY DESIGN AND SETTING

A literature review of collaborative guidelines was performed to develop an initial list of terms related to guideline collaboration. The list of terms was presented to the members of the Guideline International Network Guidelines Collaboration Working Group, who provided presumptive definitions for each term and proposed additional terms to be included. The revised list was subsequently reviewed by an international, multidisciplinary panel of expert stakeholders. Recommendations received during this pre-Delphi review were implemented to augment an initial draft glossary. The glossary was then critically evaluated and refined through two rounds of Delphi surveys and a virtual consensus meeting with all panel members as Delphi participants.

RESULTS

Forty-nine experts participated in the pre-Delphi survey, and 44 participated in the two-round Delphi process. Consensus was reached for 37 terms and definitions.

CONCLUSION

Uptake and utilization of this guideline collaboration glossary by key organizations and stakeholder groups may facilitate collaboration among guideline-producing organizations by improving communication, minimizing conflicts, and increasing guideline development efficiency.

Incidence and Significance of Deep Venous Reflux in Patients Treated with Saphenous Vein Ablation

BACKGROUND

Venous ablation (VA) of the saphenous vein is the most common procedure performed for venous insufficiency. The incidence of concomitant deep venous reflux (DVR) in patients undergoing VA is unknown. Our hypothesis is that patients undergoing saphenous VA with concomitant DVR exhibit a higher clinical, etiology, anatomy, and pathophysiology (CEAP) stage and less relief after VA compared to patients without DVR.

METHODS

Electronic medical records of patients treated with saphenous VA at a tertiary care center from March 2012 to June 2016 were reviewed. Patients were divided into 2 groups based on presence or absence of DVR on initial ultrasound (US) before saphenous VA. Patient characteristics and outcomes were compared. A telephone survey was conducted to assess long-term symptomatic relief, compliance with compression, and pain medication use. Subgroup analysis of patients with post-thrombotic versus primary DVR was performed.

RESULTS

362 patients underwent 497 ablations, and the incidence of DVR (>1 sec) was 20% (N = 71). Patients with DVR were significantly more likely to be male (46.4% vs. 32.1%, P = 0.021) and of Black race (21.2% vs. 5.5%, P = 0.0001) compared to patients without DVR. Patients with DVR were more likely to have a history of deep vein thrombosis (DVT) (15.1% vs. 7.9%, P = 0.045), but there was no difference in other comorbidities. There was no significant difference in presenting symptoms, CEAP stage, or symptom severity based on numeric rating scale (NRS) (0-10) for pain and swelling. Clinical success of saphenous VA was comparable between the 2 groups, but patients with DVR were more likely to develop endovenous heat-induced thrombosis (EHIT) II-IV (6% vs. 1%, P = 0.002). After a mean follow-up of 26 months, there was still no difference in pain or swelling scores, but patients with DVR were more likely to use compression stockings and used them more frequently. Only 11 of 71 patients with DVR had a history of DVT. Patients with post-thrombotic DVR were significantly older than patients with primary DVR (67.3 vs. 57.2, P = 0.038) and exhibited a trend toward more advanced venous disease (C4-C6: 45.4% vs. 33.3%, P = 0.439).

CONCLUSIONS

In this study, 20% of patients undergoing saphenous VA demonstrated DVR, which was more common in Black men. Presence of DVR is associated with increased risk of EHIT after saphenous VA but does not seem to impact disease severity or clinical relief after ablation. Larger studies are needed to understand outcome differences between post-thrombotic and primary DVR.

Venous outflow banding for maturation of a percutaneous arteriovenous fistula

In the present report, we have described venous outflow banding as a technique to assist with maturation of a percutaneous arteriovenous fistula (pAVF) without sacrificing potential target veins for future access. A 47-year-old obese man had undergone pAVF creation between the right ulnar vessels with coil embolization of the brachial vein. Follow-up imaging demonstrated the median cubital vein briskly filling the cephalic and basilic veins. The basilic vein was banded with the patient under local anesthesia successfully. Banding of the superficial veins provides an alternative after creation of a pAVF to preserve veins that could be used as conduits for future access.

Reinterventions in Patients with Claudication and Chronic Limb Threatening Ischemia

BACKGROUND

Patients with peripheral artery disease (PAD) present with claudication or chronic limb threatening ischemia (CLTI). CLTI patients have a more advanced stage of atherosclerosis and increased comorbidities compared to claudicants, and are at an elevated risk of major amputation and mortality after lower extremity revascularization (LER). However, the frequency of reinterventions for claudication and CLTI have not been compared. Our hypothesis is that patients with CLTI undergo more frequent reinterventions to prevent major amputation.

METHODS

A single-center retrospective chart review of consecutive patients undergoing lower extremity revascularization (LER) for PAD in 2013-2015 was performed. Patients were stratified based on indication for revascularization into claudication or CLTI. Patient characteristics, outcomes, and reinterventions were compared between the 2 groups.

RESULTS

There were 826 patients undergoing LER and 44% (N = 361) had CLTI. Patients treated for CLTI were more likely to be smokers (P < 0.001), to have diabetes (P< 0.001), chronic renal insufficiency (P< 0.001), end stage renal disease (P< 0.001), and cardiac disease (P< 0.001). CLTI patients were less likely to be on optimal medical management as reflected by decreased rate of aspirin (P< 0.001), ADP receptor/P2Y12 inhibitors (P< 0.001), and statins (P< 0.001) compared to patients with claudication. Patients with CLTI had significantly higher major amputation (3.7% vs. 0.2%, P< 0.001) and mortality (1.4% vs. 0.2%, P = 0.092) at 30 days. At long-term follow up, patients with CLTI had higher rates of major amputation (15.5% vs. 1.3%, P < 0.001) and mortality (37.1% vs. 18.1%, P < 0.001) compared to patients with claudication. There was a significant difference in mean follow-up time between the 2 cohorts (claudication: 3.7 ± 1.5 years versus CLTI: 2.6 ± 1.8 years, P < 0.001). There was no significant difference in the ipsilateral reintervention rate between the 2 groups (claudication: 39.6% vs. CLTI: 42.7%, P = 0.37) or the mean number of ipsilateral reinterventions (claudication: 2.0 ± 1.6 vs. CLTI: 2.0 ± 1.7). However, after adjusting for follow-up time, the mean number of reinterventions per year was significantly higher for CLTI patients compared to patients with claudication (1.4 ± 2.2 vs. .6 ± 0.7 intervention per year, P < 0.001).

CONCLUSIONS

Patients undergoing LER for CLTI undergo more frequent reinterventions over time compared to patients treated for claudication. Research on reinterventions after LER should include reporting of the frequency of reintervention adjusted for the follow up period in addition to the reintervention rate defined as the percentage of patients undergoing reintervention.

Superselective carotid body tumor embolization with platinum-based coils

Resection of Shamblin II and III carotid body tumors can be challenging owing to the potential for significant blood loss. Prophylactic use of liquid embolic agents poses a risk of inflammatory reactions and nontarget embolization. On the other hand, coil embolization has traditionally been limited to cases involving external carotid artery sacrifice. Herein we demonstrate that superselective targeting of tumor-feeding vessels using platinum based, fully detachable packing coils is effective at sustained devascularization of Shamblin II and III carotid body tumors without subsequent inflammation, allowing for a longer interval between embolization and tumor resection, and potentially reducing blood loss without need for ligation or reconstruction of the internal or external carotid artery.

The Effect of Gender on Early and Intermediate Results of Endovascular Aneurysm Repair

Results of endovascular aneurysm repair (EVAR) may be gender dependent. Between September 1997 and September 2001, 118 AneuRx aortic grafts were placed for aneurysmal disease. During this period, 17 females and 101 males were treated with this device. A prospective database was maintained and supplemented with retrospectively gathered information to evaluate early and mid-term end points. A total of 113 devices were deployed in 118 attempts. Length of procedure was greater for females (3.3 +/- 1.75 vs. 2.3 +/- 0.8 hr, p = 0.05) and they were more likely to have significant arterial dissections (12% vs. 1%, p = 0.05). The mortality rates at 1 month were 12% for females and 0% for males ( p = 0.02); the complication rates at 1 month were 41% for females and 15% for males ( p = 0.02). Although technical success was not significantly different between the sexes, assisted primary technical success (requiring endovascular assistance) and assisted secondary technical success (requiring open surgical assistance) were significantly different (71% vs. 96%, p = 0.003; and 76% vs. 98%, p = 0.004, respectively). Clinical success at 1 month was 59% for females and 84% for males ( p = 0.02). This difference was also significant when assessing 1-month assisted primary clinical success (59% vs. 90%, p = 0.003) and assisted secondary clinical success as well (71% vs. 96%, p = 0.003). Clinical success and assisted primary clinical success were not different at 6- or 12-month intervals, however, assisted secondary clinical successes differed at both time intervals (56% vs. 83%, p = 0.02; and 56% vs. 81%, p = 0.05, respectively). As-yet undetermined factors appear to predispose females to complications and technical difficulties in the short term. Endovascular and open procedures required to achieve ongoing clinical success in the following months appear to favor males to a greater degree than females.

Influence of NASCET/ACAS trial eligibility on outcome after carotid endarterectomy

PURPOSE

Proponents of carotid angioplasty and stenting suggest that "high risk" patients, defined as patients excluded from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and Asymptomatic Carotid Atherosclerosis Study (ACAS), may have a significantly higher risk of stroke with carotid endarterectomy (CEA). However, this selected patient cohort has been poorly studied.

METHODS

A retrospective review of patients who underwent CEA during a 2-year period at a tertiary referral institution was performed. Each patient was evaluated and categorized, according to the exclusion criteria, by NASCET and ACAS standards. Statistical analysis using chi(2) and Fisher exact tests was performed.

RESULTS

There were 366 CEAs performed on 348 patients, including 32 (8.7%) for recurrent stenosis. A subgroup of 169 (46.2%) patients were trial ineligible. Focal ipsilateral symptoms were present in 148 (40.4%) of the patients. There were 9 (2.5%) strokes and 1 (0.3%) death, secondary to a major stroke, for an overall stroke and death rate of 2.5%. Trial-eligible patients had a stroke/death rate of 1.5% (3/197) while trial-ineligible patients had a 3.6% (6/169) stroke/death rate (P = .17).

CONCLUSION

Patients who were considered high risk for CEA as defined by trial ineligibility were common, comprising approximately half of our patients. Although trial-ineligible patients had a nonsignificant trend toward higher neurologic morbidity when compared with the eligible group, the risks were still comparable with NASCET/ACAS results. CEA was a safe procedure even in this "high risk" group. As such, ineligibility for a randomized carotid intervention trial should not be employed as a "de novo" indication for carotid stenting.