Endovascular stenting of supra-aortic lesions using a transcarotid retrograde approach and flow reversal: A multicenter case series.

OBJECTIVE: Endovascular treatment has largely replaced open reconstruction of proximal brachiocephalic and left common carotid ostial arterial stenoses. The objective of this study was to report the technical feasibility and safety of a flow-based embolic protection system in stenting of single and tandem stenotic lesions of supra-aortic arch vessels. METHODS: All cases used flow-based neuroprotection by the ENROUTE Transcarotid Neuroprotection System (Silk Road Medical, Sunnyvale, Calif). Case specifics, such as the stents used, the details of flow-based neuroprotection, the order in which lesions were treated, and the case-specific exceptions, are detailed in the body of the publication. The primary end point of this study was the occurrence of stroke or transient ischemic attack. RESULTS: Sixteen patients (12 women) with an average age of 68 years (range, 54-83 years) underwent endovascular stenting to treat single (11 patients) or tandem (5 patients) stenotic lesions of supra-aortic arch vessels. A total of 21 lesions were treated: 7 in the innominate artery, 1 in the right common carotid artery, 8 in the left common carotid artery, and 5 in the internal carotid artery (tandem cases). Eleven patients (69%) were symptomatic, and the stenoses of the five asymptomatic patients were identified during routine workup for comorbidities. Technical success was obtained in all cases. There were no strokes or transient ischemic attacks during the 30 days after the procedure. Minor complications included a minor wound dehiscence that healed secondarily without sequelae and a hematoma at the neck incision that resolved spontaneously without further intervention. CONCLUSIONS: The use of a transcarotid retrograde approach with flow-based neuroprotection is technically feasible for the endovascular stenting of single and tandem stenotic lesions of the supra-aortic arch vessels. These data further support the advantages of a transcarotid approach and flow-based neuroprotection to minimize the risk of intraoperative complications and embolic events during and after the procedure.

Comparative study of clinical outcome of endovascular aortic aneurysms repair in large diameter aortic necks (>31 mm) versus smaller necks.

BACKGROUND: This study compares short-term (30 days) and intermediate term (3 years) clinical outcomes in patients with large (≥31 mm) versus small aortic neck diameters (≤28 and ≤31 mm). METHODS: Prospectively collected data from 741 patients who underwent endovascular aortic aneurysm repair were analyzed. Some surgeons have reported the threshold for a large aortic neck for endovascular aortic aneurysm repair to be 28 mm, whereas for others it is 31 mm. Therefore, we classified aortic neck diameter into less than or equal to 28 versus greater than 28 mm; and less than or equal to 31 versus greater than 31 mm. Logistic regression and Kaplan-Meier analyses were used to compare outcomes. RESULTS: There were 688 patients who had a defined aortic neck diameter: 592 with less than or equal to 28 mm, 96 with greater than 28 mm, 655 with less than or equal to 31 mm, and 33 with greater than 31 mm. The mean follow-up was 25.2 months for less than or equal to 31 mm versus 31.8 months for greater than 31 mm. Clinical characteristics were similar in all groups, except that there were more patients outside the instructions for use in the greater than 31 mm versus less than or equal to 31 mm group (94% vs 44%; P < .0001). There was a significant increase in early type I endoleak for patients with an aortic neck diameter of greater than 31 versus less than or equal to 31 mm (9 [27%] vs 74 [11%]; P = .01); late type I endoleaks (4 [14%] vs 18 [3%]; P = .01); sac expansion (5 [17%] vs 28 [5%]; P = .01); late intervention (5 [17%] vs 23 [4%]; P = .01); and death (9 [31%] vs 48 [8%]; P < .0001). There were no differences in outcomes between the patients with greater than 28 mm aortic neck diameters and the less than or equal to 28 mm diameters. Freedom from late type I endoleak at 1, 2, and 3 years were 96%, 88%, and 88% for patients with a neck diameter of greater than 31 mm versus 97%, 97%, and 97% for a diameter less than or equal to 31 mm (P = .19). The rate of freedom from sac expansion for patients with a diameter greater than 31 mm was 88%, 81%, and 81% at 1, 2, and 3 years versus 99%, 97%, and 92% for a diameter less than or equal to 31 mm (P = .02). Freedom from late intervention for 1, 2, and 3 years for patients with a diameter greater than 31 mm were 91%, 91%, and 91% versus 99%, 97%, and 96% for those with a diameter less than or equal to 31 mm. Survival rates at 1, 2, and 3 years for a diameter greater than 31 mm were 83%, 74%, and 68% versus 96%, 92%, and 90% for a diameter less than or equal to 31 mm (P < .001). Multivariate logistic regression analysis showed that patients with a diameter greater than 31 mm had an odds ratio of 6.1 (95% confidence interval [CI], 2.2-16.8) for mortality, 4.7 (95% CI, 1.4-15.5) for sac expansion, and 4.9 (95% CI, 1.4-17.4) for late type I endoleak. CONCLUSIONS: Patients with large aortic neck diameters (>31 mm) had higher rates of early and late type I endoleak, sac expansion, late intervention, and mortality.

Anatomical and technical predictors of perioperative clinical outcomes after carotid artery stenting.

BACKGROUND: A few other studies have reported the effects of anatomical and technical factors on clinical outcomes of carotid artery stenting (CAS). This study analyzed the effect of these factors on perioperative stroke/myocardial infarction/death after CAS. METHODS: This was a retrospective analysis of prospectively collected data of 409 of 456 patients who underwent CAS during the study period. A logistic regression analysis was used to determine the effects of anatomical and technical factors on perioperative stroke, death, and myocardial infarction (major adverse events [MAEs]). RESULTS: The MAE rate for the entire series was 4.7% (19 of 409), and the stroke rate was 2.2% (9 of 409). The stroke rate for asymptomatic patients was 0.46% (1 of 218; P = .01). The MAE rates for patients with transient ischemic attack (TIA) were 7% (11 of 158) vs 3.2% (8 of 251) for other indications (P = .077). The stroke rates for heavily calcified lesions were 6.3% (3 of 48) vs 1.2% (4 of 332) for mildly calcified/noncalcified lesions (P = .046). Differences in stroke and MAE rates regarding other anatomical features were not significant. The stroke rate for patients with percutaneous transluminal angioplasty (PTA) before embolic protection device (EPD) insertion was 9.1% (2 of 22) vs 1.8% (7 of 387) for patients without (P = .07) and 2.6% (9 of 341) for patients with poststenting PTA vs 0% (0 of 68) for patients without. The MAE rate for patients with poststenting PTA was 5.6% (19 of 341) vs 0% (0 of 68) for patients without (P = .0536). The MAE rate for patients with the ACCUNET (Abbott, Abbott Park, Ill) EPD was 1.9% (3 of 158) vs 6.7% (16 of 240) for others (P = .029). The differences between stroke and MAE rates for other technical features were not significant. A regression analysis showed that the odds ratio for stroke was 0.1 (P = .031) for asymptomatic indications, 13.7 (P = .014) for TIA indications, 6.1 (P = .0303) for PTA performed before EPD insertion, 1.7 for PTA performed before stenting, and 5.4 (P = .0315) for heavily calcified lesions. The MAE odds ratio was 0.46 (P = .0858) for asymptomatic indications, 2.1 for PTAs performed before EPD insertion, 2.2 for poststent PTAs, and 2.2 (P = .1888) for heavily calcified lesions. A multivariate analysis showed that patients with TIA had an odds ratio of stroke of 11.05 (P = .029). Patients with PTAs performed before EPD insertion had an OR of 6.15 (P = .062). Patients with heavily calcified lesions had an odds ratio of stroke of 4.25 (P = .0871). The MAE odds ratio for ACCUNET vs others was 0.27 (P = .0389). CONCLUSIONS: Calcific lesions and PTA before EPD insertion or after stenting were associated with higher stroke or MAE rates, or both. The ACCUNET EPD was associated with lower MAE rates. There was no correlation between other anatomical/technical variables and CAS outcome.

Acute complications after balloon-assisted maturation.

BACKGROUND: Balloon-assisted maturation (BAM) of arteriovenous fistula (AVF) is a fairly new procedure used to accelerate the process of maturation. As with any procedure, complications do arise. In this retrospective analysis of 336 office-based BAM procedures, 5 major complications were analyzed. These were categorized as formation of wall hematoma, extravasation or rupture, spasm, thrombosis, and formation of puncture-site hematoma. METHODS: Prospective data were collected from May 14, 2009 to March 3, 2011 on 336 office-based duplex-guided BAM procedures. Access site puncture, vessel cannulation, wire placement, and balloon advancement and insufflation were duplex guided. Balloon calibers were chosen based on duplex vein measurements and surgeon preference (approximately 1-2 mm larger than minimal vein diameter). Vascular injuries were classified based on postprocedural duplex assessment. All patients had follow-up duplex scans within a week after BAM. RESULTS: Of the 336 procedures, the most common injury was formation of wall hematoma (136, 40.5%) followed by extravasation or rupture (32, 9.5%), spasm (26, 7.7%), formation of puncture-site hematoma (13, 3.9%), and thrombosis (5, 1.5%). The injuries were further compared based on balloon size, ranging from small balloon group (3-6 mm) to large balloon group (7-12 mm); entry position, retrograde (n=177) versus antegrade (n=159); and type of fistula; radial-cephalic (n=232), brachial-cephalic (n=64), brachial-basilic (n=34), brachial-brachial (n=4), and ulnar-cephalic (n=2). A significant increase in complications was noted in BAM procedures performed in forearm AVF versus upper arm AVF (67% vs 54%, P=0.02) and in the large balloon group versus small balloon group (72% vs 52%, P<0.001). CONCLUSIONS: The data suggest that office-based BAM procedures are safe. Fortunately, major complications are not seen at an alarming rate. While increased complications are seen in BAM procedures performed in the forearm and with larger balloons, except for wall hematoma formation (40.19%), each complication occurs in <10% of the procedures. Further studies to help clarify the nature of these complications and their relationship to fistula maturation are warranted.

A rare complication of a retained wire during endovascular abdominal aortic aneurysm repair.

We present a case of a high-risk 76-year-old man who was electively admitted for repair of a large infrarenal abdominal aortic aneurysm. After placement of the main body of the bifurcated graft, the contralateral guidewire became entrapped at the level of suprarenal fixation. Multiple endovascular maneuvers were attempted to remove this wire from the femoral approach, but all were unsuccessful. The wire was then transected at the level of the common femoral artery and anchored to the arterial wall with 1 small monofilament suture. A short bare stent was also used to secure this wire to the inner wall of the external iliac artery. However, the proximal end of the wire that extended freely up to the mid-descending aorta was left undisturbed. On postoperative day 2, an attempt at snaring the proximal end of the wire via a brachial approach also failed to displace the trapped wire. At 1-year of follow-up, the patient has been asymptomatic with no obvious sequelae, such as thromboembolism or aortic dissection, and there is no evidence of damage to the aorta or graft on computed tomographic imaging. To our knowledge, this complication has not been previously reported.

To BAM or not to BAM?: A closer look at balloon-assisted maturation.

BACKGROUND: Balloon assisted maturation (BAM) is a recent, innovative, yet controversial method for developing autogenous arterio-venous fistulae (AVF), with little supportive data. Few retrospective studies have addressed the efficacy of BAM and cofactors affecting successful maturation. We conducted a retrospective analysis of our vascular access database to compare possible factors associated with a successful BAM, as determined by increase in volume flow of the fistulae. METHODS: Between 2009 and 2010, data was prospectively collected on patients undergoing BAM of their AVF under ultrasound guidance at our institution. 30 of these patients, consisting of 143 BAMs, were retrospectively analyzed. Data collection included: past medical history, age, number of BAM procedures preformed, volume flow measurement (VFM) in mid-fistulae, size of balloon used, and presence of post procedural wall hematoma. VFM was determined with duplex within one month prior to and subsequent to each BAM performed. RESULTS: Of the 30 patients, consisting of 143 BAMs, the average age was 69 years old + 15 (range 38-92) with 20 males and 10 females. The most common risk factors were hypertension (n = 27) and diabetes mellitus (n = 16). The average BAM per patient was 4.8 (range 1-7). Of the 143 BAM procedures, 4 were excluded due to absence of preoperative or postoperative duplex. In 139 BAMs, 74 developed a post procedural hematoma as observed on duplex, and 76 showed an increase in VFM. In all BAMs analyzed, there was no correlation observed between the presence of a hematoma and increase in VFM (P = 0.87). Hematomas occurred most frequently during the second BAM procedure, with 24.3% of all hematomas observed. In 139 BAMs, 8 different balloon sizes were used, 3 mm-10 mm, with the 7mm balloon being the most frequently used (n = 34). No significant difference was noted between increase in VFM in 3 mm to 7 mm balloons. A 8 mm balloon was used in 31 BAMs with 22 developing hematomas. Of the 8mm balloon group, a statistical difference was noted between percent increase in VFM with presence of a hematoma and percent increase in VFM without presence of a hematoma (P = 0.027). CONCLUSIONS: These preliminary data, suggest that a more aggressive approach to BAM, with use of larger balloons to create hematoma formation and minimizing excessive dilatation procedures, may have a significant impact on performing a successful maturation in respects to increase in VFM.

Anatomical observations of the moderator band.

Apical ventricular septal defects are rare pathologies of the ventricular septum. The moderator band, or other large trabeculations, is the major obstacle for the repair of such defects. The aim of our study was to identify and describe variations in the size and anatomy of the moderator band. We studied the right ventricular apical trabeculations in 100 adult human cadavers. Overall, we identified the moderator band in 92% of hearts. In just over two-fifths (42%), the band was a short and thick trabeculation, whereas, in one-eighth (12%), it was long and thick. In just under one-quarter of the hearts (24%), the band was short and thin, whereas it was long and thin in 14% of the hearts. In the remaining eight hearts, we were unable to identify the moderator band. The mean thickness of the band was 4.5 +/-1.8 mm, and its mean length was 16.23 +/- 2.3 mm, ranging from 11.3 to 24.3 mm. According to these measurements, we were able to classify the band as originating less than 45% of the distance from the tricuspid valve to the apex (closer to tricuspid valve), seen in 12 hearts, between 45 and 55% of the distance from the valve to the apex, seen in 45 hearts, and greater than 55% of this distance (closer to the apex), seen in 39 specimens. We present these data that may prove useful in the setting of the surgical repair of apical ventricular septal defects through the right atrium.

Chiari's network: review of the literature.

The Chiari network, present in approximately 2% of the population, and is a reticulated network of fibers originating from the Eustachian connecting to different parts of the right atrium. Its presence results from incomplete reabsorption of the right valve of the sinus venosus. Chiari's network is often clinically insignificant. However, it has been reported to be involved in the pathogenesis of thromboembolic disease, endocarditis, arrhythmias, and entrapment of catheters upon percutaneous intervention. While initially discovered and researched using autopsy dissections, Chiari's network is often found as an incidental finding on diagnostic imaging studies, thus providing new methods for studying its incidence and clinical significance.

Recent trends in publications of US vascular surgery program directors.

AIM: We reviewed the number of vascular publications listed in PubMed from 2001 to 2009 for US program directors in vascular surgery and suggest that this can be used as a benchmark. METHODS: PubMed listed 3284 citations published during this time period. The average number of citations in PubMed per program director was 3.68 per year. The top third produced 67% of the publications. Journal of Vascular Surgery publications made up 37%. No statistical differences could be ascertained between the regions of the country and the number of publications. RESULTS: Compared to the first six years, the number of citations decreased during the last three years (13%). During the first period, there were no programs with no publications and seven with no Journal of Vascular Surgery publication. During the last three years, there were seven programs with no publications and 19 programs with no Journal of Vascular Surgery publications. The number of aortic-endovascular citations peaked in 2002 and 2003, while the number of open and basic science citations decreased. Imaging citations peaked in 2003-2005, and carotid-endovascular, vein-endovascular, and thoracic aortic-endovascular citations climbed. CONCLUSIONS: The decrease in the number of citations/program/year raises concern about the level of academic activity in vascular surgery. Overall, the annual distribution of the topic of these citations represents a continued shift from open to endovascular cases and decreasing basic science citations.

Use of duplex guided stent graft placement to prevent bleeding from previously thrombosed pseudo-aneurysms during thrombolytic therapy for acute popliteal artery occlusion.

We present a 68-year-old female who developed multiple pseudo-aneurysms (PSAs) following cardiac catheterization via the right groin. During subsequent thrombin injection of PSAs, the patient developed acute occlusion of the popliteal artery. A covered stent was placed to obliterate the PSAs and allow for successful endovascular treatment of the occlusion without hemorrhage from the previous arteriotomy sites. This report demonstrates a safe and successful method to treating high surgical risk patients with recent PSA's and a necessity for thrombolysis.