Ascending aortic geometry and its relationship to the biomechanical properties of aortic tissue.

Objective: The objective of this study was to evaluate the relationship between ascending aortic geometry and biomechanical properties. Methods: Preoperative computed tomography scans from ascending aortic aneurysm patients were analyzed using a center line technique (n = 68). Aortic length was measured from annulus to innominate artery, and maximal diameter from this segment was recorded. Biaxial tensile testing of excised tissue was performed to derive biomechanical parameters energy loss (efficiency in performing the Windkessel function) and modulus of elasticity (stiffness). Delamination testing (simulation of dissection) was performed to derive delamination strength (strength between tissue layers). Results: Aortic diameter weakly correlated with energy loss (r 2 = 0.10; P < .01), but not with modulus of elasticity (P = .13) or delamination strength (P = .36). Aortic length was not associated with energy loss (P = .87), modulus of elasticity (P = .13) or delamination strength (P = .90). Using current diameter guidelines, aortas >55 mm (n = 33) demonstrated higher energy loss than those <55 mm (n = 35; P = .05), but no difference in modulus of elasticity (P = .25) or delamination strength (P = .89). A length cutoff of 110 mm was proposed as an indication for repair. Aortas >110 mm (n = 37) did not exhibit a difference in energy loss (P = .40), modulus of elasticity (P = .69), or delamination strength (P = .68) compared with aortas <110 mm (n = 31). Aortas above diameter and length thresholds (n = 21) showed no difference in energy loss (P = .35), modulus of elasticity (P = .55), or delamination strength (P = .61) compared with smaller aortas (n = 47). Conclusions: Aortic geometry poorly reflects the mechanical properties of aortic tissue. Weak association between energy loss and diameter supports intervention at larger diameters. Further research into markers that better capture aortic biomechanics is needed.

Outcomes in octogenarians after thoracoabdominal and juxtarenal aortic aneurysm repair using fenestrated-branched devices justifies treatment.

OBJECTIVE: To compare outcomes between octogenarians and nonoctogenarians undergoing thoracoabdominal aortic aneurysm repair and juxtarenal aortic aneurysm repair using branched and/or fenestrated endovascular devices (F/BEVAR) and compare octogenarian survival to population survival statistics from Ontario, Canada. METHODS: Patients who underwent F/BEVAR at a single institution between 2007 and 2020 were retrospectively reviewed with a median follow-up of 3.3 years (interquartile range, 1.6-5.3). The median survival of an average 84-year-old Ontarian from Canada, adjusted for a male:female ratio of 4:1, was retrieved from publicly available Statistics Canada data. RESULTS: In total, 68 octogenarians (25.8%) and 196 nonoctogenarians (74.2%) were included (mean age, 83.5 ± 3.0 vs 71.9 ± 5.8 years; P ≤ .001). The maximum aneurysm size was significantly larger in octogenarians (68.9 ± 11.4 mm vs 65.4 ± 10.0 mm; P = .017). No differences in the number of thoracoabdominal aortic aneurysm repairs (29.4% vs 38.3%; P = .19) or operative technical success (92.6% vs 85.7%; P = .136) were observed between the two cohorts. Postoperatively, no significant differences in overall in-hospital mortality (7.3% vs 5.1%; P = .49), elective in-hospital mortality (6.1% vs 4.4%; P = .49), stroke (1.5% vs 3.6%; P = .384), or spinal cord ischemia (2.9% vs 9.2%; P = .094) were seen between octogenarians and nonoctogenarians. There was no difference in survival at 4 years between the two cohorts (62.9% vs 71.1%; P = .22), however, survival at 6 years was significantly lower for octogenarians (44.5% vs 64.1%; hazard ratio, 1.96; P = .02). The cumulative rate of reintervention (44.1% vs 41.3%; P = .84) and freedom from branch instability (67.6% vs 73.5%; P = .33) at 6 years were not different between the two groups. When comparing octogenarians who survived to discharge from index hospitalization after F/BEVAR with 84-year-old Ontarians unmatched for comorbidities, a survival difference of 4.8% and 11.1% was noted at 4 and 6 years, respectively. CONCLUSIONS: F/BEVAR in octogenarians is associated with no differences in technical success or postoperative adverse outcomes when compared with their younger counterparts. Octogenarians had increased mortality after 4 years and their survival at 4 years was comparable with that of an 84-year-old Ontarian. F/BEVAR was safe and effective in octogenarians deemed fit for intervention. Further research into preoperative patient selection and improving perioperative outcomes is needed.

Females experience elevated early morbidity and mortality but similar midterm survival compared to males after branched/fenestrated endovascular aortic aneurysm repair.

OBJECTIVE: The objective of this study was to identify sex-related differences in outcomes following branched and/or fenestrated endovascular aortic repair (B/FEVAR) for thoracoabdominal (TAAA) and juxtarenal (JRAA) aortic aneurysms. METHODS: Chart review completed on 242 B/FEVAR patients (57 female; 23.5%) between 2007 and 2020 at a single center. Median follow-up time was 3.3 years (interquartile range [IQR], 1.6-5.3 years). RESULTS: No statistically significant differences in age (females, 75.9 ± 5.4 years vs males, 74.7 ± 7.2 years; P = .162) or aneurysm size (64.9 ± 6.8 vs 65.8 ± 9.4 mm; P = .41) at presentation were observed between sexes. Females presented with fewer JRAAs (45.6% vs 73%; P < .001) and received more Crawford extent II (26.3% vs 10.8%; P =.004) TAAA coverage. Increased incidence of moderate/severe target vessel stenosis (29.8% vs 14%; P = .022) was observed in female patients. Intraoperatively, females had higher procedure times (530 [IQR, 425-625] vs 420 [IQR, 350-510] minutes; P < .001), fluoroscopy times (124.1 ± 49 vs 107.3 ± 43.5 minutes; P = .017), and contrast usage (200 [IQR, 150-270] vs 175 [IQR, 130-225] mL; P = .005). Unplanned intraoperative maneuvers (45.6% vs 28.1%; P = .043), graft delivery issues (24.6% vs 4.9%; P < .001), and additional intraoperative complications (61.4% vs 35.7%; P < .001) were also increased in females. Postoperatively, females had a longer intensive care unit (3 [IQR, 1-5] vs 1 [IQR, 1-3] days; P = .002) and hospital stay (8 [IQR, 5-13] vs 5 [IQR, 3-9] days; P < .001) and experienced increased rates of spinal cord ischemia (15.8% vs 3.8%; P = .001) and bowel ischemia (10.5% vs 2.7%; P = .013). In-hospital mortality (12.3% vs 2.7%; P = .004) was higher in female patients but midterm (6-year) survival was 60.2% for all patients (95% confidence interval, 53.0%-68.5%) and was similar between sexes (hazard ratio, 0.95; P = .83), which were the primary endpoints. No sex differences in midterm follow-up reintervention, endoleak, and rupture rates were observed. CONCLUSIONS: Females experienced significantly higher B/FEVAR intraoperative times, complications, and in-hospital morbidity and mortality compared with males but similar midterm outcomes. Anatomic and atherosclerotic differences may have contributed to the observed in-hospital differences.

Percutaneous Drainage for Aortic Graft Infection Post-aneurysm Repair: A Viable Option?

PURPOSE: Non-operative management of aortic graft infection is usually only considered in a palliative context. We describe the safety, efficacy, and clinical outcomes of percutaneous drainage of aortic graft infections (AGI) following either open or endovascular repair of aneurysmal disease. METHODS: Twelve consecutive patients (11 males, 1 female, mean age 72.7 ± 10.3 years, age range 52-88 years) between January 2010-July 2020 who underwent percutaneous drain insertion in either an infected aortic sac or periaortic abscess cavity following endovascular or open surgical graft repair were identified. Patient and procedural characteristics as well as clinical outcomes were determined. RESULTS: Of the 12 patients who underwent percutaneous drain insertion, five (41.7%) had undergone open abdominal aneurysm repair, one (8.3%) open thoracoabdominal aneurysmal repair, and six (50%) endovascular abdominal aneurysm repairs. Drain size ranged from 10-20 French. All were inserted under ultrasound (US), computed tomography (CT), and/or fluoroscopic guidance. Median duration of drain placement was 55.2 days (range 3-174). Five patients (41.7%) had the drain in place as a stabilizing bridge until or after definitive surgical explantation and aortic reconstruction. Seven patients (58.3%) were managed with drain placement and antibiotic therapy without surgical intervention. Six (50%) were alive at the most recent time of follow-up (median, 732 days, range 166-1650 days). Three patients (25%) died during follow-up with causes including erosion of aortic reconstruction into sigmoid colon, unrelated chronic obstructive pulmonary disease exacerbation, and severe clostridium difficile colitis and pseudomonal pneumonia (median 1244 days, range 992-1597 days). Three (25%) patients were lost to follow-up. No drain-related complications were noted. CONCLUSION: Percutaneous drainage of AGI following endovascular or open aneurysm repair is a safe and viable management option either as a temporizing measure as a bridge to surgical graft explantation or as a non-surgical therapy for long term management.

Importance of computed tomography in defining segmental disease in chronic thromboembolic pulmonary hypertension.

BACKGROUND: Radiological assessment of patients with chronic thromboembolic pulmonary hypertension (CTEPH) is critical to decide whether patients should be treated with pulmonary endarterectomy (PEA). Although computed tomography pulmonary angiography (CTPA) is increasingly used for decision making in CTEPH, the value of CTPA to predict surgical findings and outcome has never been explored. METHODS: We retrospectively reviewed 100 consecutive patients with high-quality CTPA undergoing PEA for CTEPH between May 2015 and December 2017. The most proximal level of disease in the pulmonary artery on CTPA was classified by two blinded radiologists as level 1 (main pulmonary artery), 2a (lobar pulmonary artery), 2b (origin of basal segmental pulmonary artery), 3 (segmental pulmonary artery) or 4 (predominantly subsegmental pulmonary artery). RESULTS: CTPA demonstrated level 1 in 20%, level 2a in 43%, level 2b in 11%, level 3 in 23% and level 4 in 3%. A majority of males presented with level 1 (55%) and level 2 (57%), and a majority of females (83%) with level 3 (p=0.01). Levels 3 and 4 were associated with longer duration of circulatory arrest (p=0.03) and higher frequency of Jamieson type III disease at surgery (p<0.0001). Requirement for targeted pulmonary hypertension therapy after PEA was 28% at 3 years in level 2b/3/4 compared with 6% in level 2a and 13% in level 1 (p=0.002). Level 2b/3/4 was an independent predictor for targeted pulmonary hypertension therapy after PEA (hazard ratio 4.23, 95% CI 1.24-14.39; p=0.02). CONCLUSIONS: High-quality CTPA provides accurate evaluation of CTEPH patients. The level of disease on CTPA can help guide peri-operative planning and post-operative monitoring.

IVC filter removal after extended implantation periods.

OBJECTIVE: Life-threatening complications have been reported in patients with chronic retrievable IVC filters. National health agencies have urged hospitals to assess all patients with retrievable IVC filters for filter removal. The aim of the current study was to identify those patients with unretrieved chronic IVC filters, document complications and removal techniques. METHODS: We identified a cohort with unretrieved IVC filters inserted between January 2001 and December 2013. These patients were invited back to clinic for review with CT imaging to determine complications, if any, and offer removal. Data collected included demographics, complications and retrieval characteristics. RESULTS: 289 patients were discovered to still have a filter in situ. Of these, 193 patients were verified as deceased. Eighty-nine patients were notified, with no current contact information available on the remaining seven. Thirty-six attended for review, 20 females, 16 males, with an average age of 63.5 years. Complications identified at CT were 2 occluded IVCs (5.8%), 4 fractured filters (11.7%) and filter penetration in all cases (37.5% grade 2, 56.25% grade 3). Sixteen patients agreed to proceed with filter removal, 10 declined the opportunity and 6 were unfit or had ongoing indication for the filter. Two are awaiting removal and two had IVC occlusion. Subsequent retrieval was successful in 93% of cases (14/15). The mean time to removal from implant was 3846.9 days (SD 980.3). Advanced techniques were utilized in 10 cases and there were no mortalities or morbidities. CONCLUSION: Retrievable inferior vena cava filters are not benign and practitioners need to be aware of regulatory guidelines. Unretrieved filters can be successfully retrieved using standard and advanced methods with low morbidity and mortality.

Initial Experience With Viabahn VBX as the Bridging Stent Graft for Branched and Fenestrated Endovascular Aneurysm Repair.

PURPOSE: To evaluate the feasibility and safety of a novel balloon-expandable, heparin-bonded endoprosthesis (Viabahn VBX, W. L. Gore and Associates) when used as a bridging stent graft (BSG) with fenestrated and branched endovascular aneurysm repair (FB-EVAR). FB-EVAR and BSGs increase repair complexity with the potential for endoleak formation, stenosis, thrombosis, and graft migration. The mechanical construction of the Viabahn VBX and its antithrombogenic properties may provide an advantage for FB-EVAR over existing BSGs. The efficacy, safety, and clinical outcomes were assessed. MATERIALS AND METHODS: Research ethics board approved, prospective, single arm cohort, pilot study of patients undergoing FB-EVAR between February 2017 and January 2018. Fenestrated and branched endovascular aneurysm repair was performed per the standard institutional protocol by a team composed of vascular surgeons and interventional radiologists. Viabahn VBX endografts were used for all intended visceral branches as long as appropriately sized devices were available (Under Investigational Testing Authorization from Health Canada). Patient characteristics, procedural details, and technical and clinical outcomes were reviewed and summarized. RESULTS: FB-EVAR was performed in 13 patients (9 male and 4 female) mean age of 74 (range: 61-83) with a total of 41 Viabahn VBXs stents implanted. Mean maximum aneurysm size was 6.7 cm (range: 5.5-9.0 cm) and included 5 juxtarenal abdominal aortic aneurysms and 8 thoracoabdominal; 3 type V, 3 type IV, and 2 type III (Crawford Classification). The Viabahn VBX was successfully deployed in 40 (98%) of 41 of cases. At median follow-up of 223 days (range: 2-462), there was a (40/40) 100% Viabahn VBX patency rate. Seven endoleaks were identified intra- or post procedurally in 6 (46%) of 13 cases, including 1 type IB, 3 type II, 2 type III, and 1 unclassified. Nine complications occurred in 6 patients. CONCLUSION: The Viabahn VBX stent is a safe and effective BSG for FB-EVAR with no early stent thrombosis. Further evaluation is required to determine longer term stent efficacy.

Effect of portal vein embolization on treatment plan prior to major hepatectomy for hepatocellular carcinoma.

BACKGROUND: Portal vein embolization (PVE) is used before major hepatectomy for hepatocellular carcinoma (HCC) to increase future liver remnant (FLR) volume. However, this may increase tumour growth rate, leading to more extensive resections. This study aimed to determine the effect of tumour growth, following PVE, on treatment plan. METHOD: Retrospective cohort study conducted on patients treated from 2008 to 2015 with PVE before major hepatectomy for HCC. Liver and tumour volumetry was performed on pre- and post-PVE CT scans. Image-based and actioned plans were compared before and after PVE. RESULTS: Thirty-one patients received PVE. Non-tumour total liver volume decreased (median 1440 to 1394 cm3; p = 0.031), while tumour (median 161-240 cm3; p < 0.001) and FLR volumes (median 430-574 cm3; p < 0.001) increased. The treatment plan changed in 15/31 patients: more extensive resection (n = 6), less extensive resection (n = 1), no resection as scheduled (n = 8). Tumour progression accounted for a clinically relevant change in treatment plan in 8/31 patients. CONCLUSION: Following PVE in the setting of HCC, tumour progression accounts for a change in treatment plan in approximately a quarter of patients. Further research is warranted to determine whether additional liver directed therapy should routinely be used to slow the growth of HCC post-PVE.

Utility of the Vascular Quality Initiative in improving quality of care in Canadian patients undergoing vascular surgery

The Vascular Quality Initiative (VQI) is a national cooperative quality-improvement initiative designed to evaluate processes of care and outcomes in vascular surgery. The purpose of this report is to show the utility of such a database to provide insight into the standard of care provided, to highlight areas of local quality improvement, to benchmark our data against local, regional and national trends, and to ultimately improve safety in Canadian patients undergoing vascular surgery. We present the history of the database, its spread in the Canadian health care system and examples of quality improvements achieved from analyses of data recorded and retrieved from the VQI. Using the VQI, our institution was able to decrease the length of stay after endovascular aneurysm repair, decrease the contrast volume in endovascular aneurysm repair, save on costs, and provide medium-term outcome data on peripheral vascular interventions and smoking cessation strategies. The VQI is a powerful tool to improve patient safety and quality in vascular surgery. Its ability to create local regional improvement groups fosters a quality-focused culture and is important for Canadian patients.

La Vascular Quality Initiative (VQI) est une initiative de collaboration nationale axée sur l'amélioration de la qualité, conçue pour évaluer les processus de soins et les résultats en chirurgie vasculaire. Le but du présent rapport est de montrer l'utilité d'une telle base de données pour situer les normes de soins actuelles, mettre en lumière les secteurs d'amélioration de la qualité locale, évaluer nos données à la lumière des tendances locales, régionales et nationales et ultimement, améliorer la sécurité des patients canadiens de chirurgie vasculaire. Nous retraçons l'historique de cette base de données, son adoption par le système de santé canadien et donnons des exemples d'améliorations de la qualité obtenues grâce à l'analyse des données enregistrées et récupérées à partir de la base VQI. Cette base de données nous a permis d'abréger les séjours hospitaliers après la réparation endovasculaire des anévrismes, d'épargner sur les coûts et de compiler les résultats à moyen terme des interventions vasculaires périphériques et des stratégies d'abandon du tabagisme. La VQI est un outil puissant pour améliorer la sécurité des patients et la qualité de la chirurgie vasculaire. Sa capacité de créer des groupes loco-régionaux d'amélioration de la qualité favorise une culture axée sur la qualité et est importante pour les patients canadiens.

Non-contrast-enhanced MR angiography in critical limb ischemia: performance of quiescent-interval single-shot (QISS) and TSE-based subtraction techniques.

PURPOSE: The aim of this study was to evaluate diagnostic performance of non-contrast-enhanced 2D quiescent-interval single-shot (QISS) and 3D turbo spin-echo (TSE)-based subtraction magnetic resonance angiography (MRA) in the assessment of peripheral arteries in patients with critical limb ischemia (CLI). MATERIALS AND METHODS: Nineteen consecutive patients (74 % male, 72.8 ± 9.9 years) with CLI underwent 2D QISS and 3D TSE-based subtraction MRA at 1.5 T. Axial-overlapping QISS MRA (3 mm/2 mm; 1 × 1 mm2) covered from the toes to the aortic bifurcation while coronal 3D TSE-based subtraction MRA (1.3 × 1.2 × 1.3 mm3) was restricted to the calf only. MRA data sets (two readers) were evaluated for stenosis (≥50 %) and image quality. Results were compared with digital subtraction angiography (DSA). RESULTS: Two hundred and sixty-seven (267) segments were available for MRA-DSA comparison, with a prevalence of stenosis ≥50 % of 41.9 %. QISS MRA was rated as good to excellent in 79.5-96.0 % of segments without any nondiagnostic segments; 89.8-96.1 % of segments in 3D TSE-based subtraction MRA were rated as nondiagnostic or poor. QISS MRA sensitivities and specificities (segmental) were 92 % and 95 %, respectively, for reader one and 81-97 % for reader two. Due to poor image quality of 3D TSE-based subtraction MRA, diagnostic performance measures were not calculated. CONCLUSION: QISS MRA demonstrates excellent diagnostic performance and higher robustness than 3D TSE-based subtraction MRA in the challenging patient population with CLI. KEY POINTS: • QISS MRA allows reliable diagnosis of peripheral artery stenosis in critical limb ischemia. • Robustness of TSE-based subtraction MRA is limited in critical limb ischemia. • QISS MRA allows robust therapy planning in PAD patients with resting leg pain.

Twelve-Month Results of the Nitinol Astron Stent in Iliac Artery Lesions.

PURPOSE: To evaluate the safety and efficacy of a self-expanding bare-metal nitinol stent (Astron; BIOTRONIK AG, Bülach, Switzerland) for the treatment of atherosclerotic lesions in the common and external iliac arteries. This study tested the hypothesis that the major adverse event (MAE) rate at 12 months was less than or equal to a performance goal of 15%. MATERIALS AND METHODS: In a prospective study that began in November 2011, 161 patients with symptomatic iliac lesions were treated with an Astron stent in the United States, Canada, and Austria. The primary endpoint was a composite rate of procedure- and stent-related MAEs at 12 months that included 30-day mortality, clinically indicated target lesion revascularization (TLR), and index limb amputation. RESULTS: The MAE rate at 12 months was 2.1% (3/146; [95% CI: 0.4% to 5.9%]; p < 0.001). The acute procedural success and 30-day clinical success outcomes were both 95% (153/161). The primary patency rate at 12 months was 89.8% (115/128). The comparison of baseline and 12-month Ankle Brachial Index (ABI) measurements showed a mean increase of 0.23 ± 0.19 (p < 0.001). The Walking Impairment Questionnaire (WIQ) PAD specific score, walking distance score, walking speed score and stair climbing score paired each showed a significant increase from baseline to 12 months (p<0.001). CONCLUSIONS: The Astron stent system was shown to be safe and effective in the treatment of patients with atherosclerotic disease. The observed MAE rate met the pre-specified performance goal of 15%. The stent demonstrated a high 12-month primary patency rate and showed improvement in quality of life measures.

Comparison of Clinical Outcomes following Glue versus Polyvinyl Alcohol Portal Vein Embolization for Hypertrophy of the Future Liver Remnant prior to Right Hepatectomy.

PURPOSE: To report outcomes after portal vein embolization (PVE) and right hepatectomy in patients receiving embolization with N-butyl cyanoacrylate (NBCA) glue + central AMPLATZER Vascular Plug (AVP; glue group) or polyvinyl alcohol (PVA) particles ± coils (PVA group). MATERIALS AND METHODS: Between March 2008 and August 2013, all patients having PVE with NBCA + AVP or PVA ± coils before right hepatectomy were retrospectively reviewed; 85 patients underwent PVE with NBCA + AVP (n = 45) or PVA ± coils (n = 40). The groups were compared using Mann-Whitney U and χ2 tests. RESULTS: Technical success of embolization was 100%. Degree of hypertrophy (16.2% ± 7.8 vs 12.3% ± 7.62, P = .009) and kinetic growth rate (3.5%/wk ± 2.0 vs 2.6%/wk ± 1.9, P = .016) were greater in the glue group versus the PVA group. Contrast volume (66.1 mL ± 44.8 vs 189.87 mL ± 62.6, P < .001) and fluoroscopy time (11.2 min ± 7.8 vs 23.49 min ± 11.7, P < .001) were significantly less during the PVE procedure in the glue group. Surgical outcomes were comparable between groups, including the number of patients unable to go onto surgery (P = 1.0), surgical complications (P = .30), length of hospital stay (P = .68), and intensive care unit admissions (P = .71). There was 1 major complication (hepatic abscess) in each group after PVE. CONCLUSIONS: PVE performed with NBCA + AVP compared with PVA ± coils resulted in greater degree of hypertrophy of the future liver remnant, less fluoroscopic time and contrast volume, and similar complication rates.

Radiology of advanced EVAR techniques in complex abdominal aortic aneurysms.

Advanced Endovascular Aortic Repair (EVAR) refers to devices and techniques used for endografting of aortic aneurysms that are considered anatomically unsuitable for conventional EVAR. Customised devices and modified use of conventional EVAR devices now overcome challenging landing zones. Fenestrated and branch devices, together with chimney and periscope techniques can be used to overcome proximal landing zone challenges, while iliac branch grafts and sandwich techniques have been used to address challenging distal iliac landing issues. Due to the novelty of these techniques, life-long surveillance is crucial, with CT Aortography (CTA) being the key investigation. Currently, the body of literature surrounding the imaging aspects of these techniques is scarce. The purpose of this imaging review is to illustrate the appearance of advanced EVAR in both routine surveillance and complicated cases, using conventional and novel CTA techniques. Key Points • This review updates readers about advanced endovascular repair of abdominal aortic aneurysms • It illustrates the common CT appearances following advanced EVAR • Novel CTA techniques in troubleshooting problems unique to advanced EVAR are described.

Pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension: the Toronto experience.

BACKGROUND: Pulmonary endarterectomy (PEA) is the treatment of choice for patients with chronic thromboembolic pulmonary hypertension (PH). However, this surgery remains performed in few experienced centres only. The goal of the study is to review our overall experience since the implementation of our program in August 2005. METHODS: Review all patients referred to our program between August 2005 and July 2011. RESULTS: Among 84 consecutive patients referred to our program, 52 patients underwent elective PEA and 6 emergency PEA. After PEA, 74% patients were extubated within 2 days, 71% were discharged from the intensive care unit within 4 days and 64% were discharged from hospital within 15 days. One patient undergoing elective surgery and 2 patients undergoing emergency surgery died within 30 days of surgery for an operative mortality of 1.9% after elective pulmonary endarterectomy and an overall operative mortality of 5.2%, when the 6 emergency operative cases were included. The total pulmonary vascular resistance decreased from 965±445 to 383±162 dynes per second per cm(-5) and was associated with significant improvement in World Health Organization/New York Heart Association (WHO/NYHA) functional class, 6 minutes walk distance, echocardiographic findings, and brain natriuretic peptide level at 6 months after PEA. After a median follow-up of 23 months (1-65 months), 3 patients had to be started on targeted PH therapy for deterioration of their (WHO/NYHA) functional class. CONCLUSIONS: Elective PEA can be performed with limited risk, and results in excellent early and long-term outcome. All patients diagnosed with chronic thromboembolic PH should be referred for consideration of PEA in a specialized centre.

Iliac branch graft in the treatment of complex aortoiliac aneurysms: early results from a North American institution.

PURPOSE: To describe early experience with the use of iliac branch grafts (IBGs) in aortoiliac aneurysm repair. MATERIALS AND METHODS: From July 2007 to August 2009 (25 months), 14 patients (13 men, one woman) with a mean age of 70.1 years (range, 59.3-80.0 y) were treated with IBGs. Indications were abdominal aneurysm with common iliac artery (CIA) involvement (n = 11), juxtarenal aortic aneurysm with CIA involvement (n = 1), and bilateral CIA and internal iliac artery (IIA) aneurysms (n = 1). Postoperative endoleaks and patency rate were determined with computed tomography within 1 month of implantation and 1 year thereafter, with concurrent clinical evaluation for pelvic ischemia. Mean follow-up period was 18.7 months (range, 6-35 mo). RESULTS: Technical success rate, as defined by successful implantation of IBG with no intraprocedural type I or type III endoleak, was 86% (12 of 14). A total of 14 IBGs were successfully deployed in 12 patients. Two cases of technical failure were related to excessive iliac tortuosity. The mean hospitalization duration was 6.5 days (range, 3-14 d), with zero mortality at 30 days. There were two cases of type II endoleak treated conservatively and a single case of IBG-related type III endoleak that required repeat intervention. The rest of the stent-implanted aortic and iliac aneurysms remained stable in size, with no aneurysm rupture or death recorded. All stent-implanted iliac branches remained patent on follow-up. None of the patients who received IBGs had new symptoms of pelvic ischemia. CONCLUSIONS: Iliac branch graft placement is a feasible technique with excellent short-term results in the treatment of aortoiliac aneurysms.

Effectiveness of stent-graft placement for salvage of dysfunctional arteriovenous hemodialysis fistulas.

PURPOSE: To determine the clinical effectiveness of stent-graft placement in dysfunctional autogenous hemodialysis fistulas. MATERIALS AND METHODS: Between September 2006 and June 2008, 24 Fluency Plus stent-grafts were inserted in 17 patients with failing autogenous hemodialysis fistulas (two radiocephalic, 12 brachiocephalic, and three brachiobasilic). Six fistulas were thrombosed at presentation. Indications for stent-graft insertion included 10 residual stenoses, six pseudoaneurysms, and one fistuloplasty-induced rupture. Fistula function before and after intervention was assessed with ultrasound dilution technique. RESULTS: The technical success rate was 100%, as were the anatomic and clinical success rates. Via Kaplan-Meier method, the primary access patency rates were 94.1% at 3 months (95% CI, 0.461-0.995) and 88.2% at 6 and 12 months (95% CI, 0.468-0.980). The primary lesion patency rate was 94.1% (95% CI, 0.650-0.992) at 3, 6, and 12 months. The secondary access patency rate had a point estimate of 100% at 3 months, and was 93.8% (95% CI, 0.632-0.991) at 6 and 12 months. Univariate analysis suggested that male sex and left-sided accesses were associated with a longer primary access patency rate (P = .02). The binary restenosis rate at 6 months was 5.9%. Mean transonic flow rates were 667.5 mL/min before intervention and 2,076.0 mL/min after intervention (P = .03, Wilcoxon signed-rank test). No patients were lost to follow-up. CONCLUSIONS: Stent-graft placement in dysfunctional autogenous hemodialysis fistulas is technically feasible and effective in preserving function and preventing access abandonment, with patency rates that exceed historical patency rates with angioplasty and/or uncovered stents.

The use of dynamic volumetric CT angiography (DV-CTA) for the characterization of endoleaks following fenestrated endovascular aortic aneurysm repair (f-EVAR).

Accurate endoleak classification is essential following fenestrated endovascular aneurysm repair (f-EVAR). Both endoleak type and exact source of endoleak have implications upon the urgency and complexity of future management strategies. Herein we report on a patient with a documented endoleak post-f-EVAR, in which the source of blood flow into the aneurysm sac could not be determined using conventional computed tomographic angiography. Consequently, dynamic volumetric computed tomographic angiography (DV-CTA) was employed, which clearly illustrated the site of origin of the endoleak. DV-CTA enables accurate endoleak characterization following f-EVAR, with excellent conspicuity of the source of blood flow into the aneurysm sac.

Outcomes after uterine artery embolization for pedunculated subserosal leiomyomas.

PURPOSE: To assess the safety and efficacy of uterine artery embolization (UAE) treatment of pedunculated subserosal leiomyomas. MATERIALS AND METHODS: A review of patients undergoing UAE in a 30-month period (July 2004 to December 2006) was performed. Cases in which a pedunculated subserosal tumor (volume>or=4 cm3) was embolized were analyzed. The preprocedural volumes of the pedunculated tumor and uterus and the diameter and vascularity of the tumor and stalk were recorded. Posttreatment sizes of the pedunculated leiomyoma, stalk, and uterus were recorded, as was the presence or absence of complication(s). RESULTS: A total of 240 patients underwent embolization. Pedunculated subserosal leiomyomas were treated in 16 women, with a technical success rate of 100%. Preprocedural mean tumor and uterine volumes were 372 cm3 and 789 cm3, respectively. The mean stalk diameter was 2.7 cm (range, 0.8-7.8 cm). All pedunculated leiomyomas exhibited enhancement on contrast agent-enhanced magnetic resonance (MR) imaging (n=13) or vascularity on Doppler ultrasonography (US; n=3). Stalk vascularity was noted on MR imaging in 13 patients and was not assessed in the remaining three, who underwent US imaging. Imaging follow-up (mean, 5.9 months after UAE) demonstrated mean tumor volume reduction of 39.3% (95% confidence interval [CI], 28.2%-50.5%) and mean uterine volume reduction of 37.6% (95% CI, 26%-49.3%). There were no cases of continued tumor perfusion and no major complications. There was one minor complication of prolonged hospital stay (36 hours) for pain control. CONCLUSION: UAE was successfully and safely performed for pedunculated subserosal leiomyomas, with a tumor volume reduction of 39% and no unique complications related to these lesions.

Clinical failure after uterine artery embolization: evaluation of patient and MR imaging characteristics.

PURPOSE: To investigate the patient and magnetic resonance (MR) imaging characteristics associated with clinical failure after uterine artery embolization (UAE). MATERIALS AND METHODS: Seventy-eight consecutive patients who underwent UAE were examined. Contrast-enhanced MR imaging was performed before and 4 months after the procedure, and clinical follow-up was performed at 15 months. Patients were divided into success and failure groups strictly on the basis of their clinical outcomes. Clinical follow-up included evaluation of fibroid symptoms and the need for further treatment after UAE. Findings at pre- and postprocedural MR imaging were compared, and data collected included changes in uterine and fibroid volumes, fibroid location, and fibroid perfusion. RESULTS: Fifty-eight patients were placed into the success group and 20 into the failure group. There were no differences between the baseline characteristics of the two groups. The reduction in uterine and dominant fibroid volumes was greater in the success group compared with the failure group; however, the difference was not statistically significant (success group: [295/845] 34.9% vs [80/282.5] 28.3%, respectively, P=.18; failure group: [317/733] 43.2% vs [114/337.6] 33.9%, P=.32). The reduction in total fibroid volume was greater in the success group than the failure group ([189.6/393.5] 48.2% vs [148.7/439.9] 33.8%, respectively; P=.02) despite the fact that the percentage of fibroids completely infarcted was similar between the two groups ([136/172] 79% vs [41/50] 82%, P=.77). Pedunculated subserosal fibroids were more common in the failure group than in the success group (P<.03) and did not reduce in volume as significantly (53.8% vs 14.7%, respectively; P=.02). CONCLUSIONS: In general, the reduction in total fibroid volume after embolization is smaller in patients with poor clinical improvement. In addition, these patients have a higher number of pedunculated subserosal fibroids, and these fibroids tend to reduce in volume to a lesser extent.