Case series of aortic arch disease treated with branched stent-grafts.

BACKGROUND: Surgical repair of aortic arch pathology is complex and associated with significant morbidity and mortality. Alternative approaches have been developed to reduce these risks, including the use of thoracic stent-grafts with fenestrations or in combination with bypass procedures to maintain supra-aortic trunk blood flow. Branched stent-grafts are a novel approach to treat aortic arch pathology. METHODS: Consecutive patients with aortic arch disease presenting to a single university hospital vascular centre were considered for branched stent-graft repair (October 2010 to January 2017). Patients were assessed in a multidisciplinary setting including a cardiologist, cardiac surgeon and vascular surgeon. All patients were considered prohibitively high risk for standard open surgical repair. The study used reporting standards for endovascular aortic repair and PROCESS (Preferred Reporting of Case Series in Surgery) guidelines. RESULTS: Some 30 patients (25 men) underwent attempted branch stent-graft repair. Mean age was 68 (range 37-84) years. Eighteen patients had chronic aortic dissection, 11 patients had an aneurysm and one had a penetrating ulcer. Fourteen patients had disease in aortic arch zone 0, six in zone 1 and ten in zone 2. Twenty-five patients had undergone previous aortic surgery and 24 required surgical revascularization of the left subclavian artery. Technical success was achieved in 27 of 30 patients. Four patients had an endoleak (type Ia, 1; type II, 3). The in-hospital mortality rate was three of 30. Mean length of follow-up was 12·0 (range 1·0-67·8) months, during which time 12 patients required an aortic-related reintervention. CONCLUSION: Repair of aortic arch pathology using branched stent-grafting appears feasible. Before widespread adoption of this technology, further studies are required to standardize the technique and identify which patients are most likely to benefit.

Evaluation of a new imaging software for aortic endograft planning.

OBJECTIVE: The aim of this study was to evaluate a new 3D Workstation workflow (EVAR Assist, Advantage Windows, GE Healthcare, Chalfont, UK) (EA-AW) designed to simplify complex EVAR planning. PATIENTS AND METHODS: All pre-operative computed tomography (CT) scans of patients who underwent repair at our institution of a complex aortic aneurysm using fenestrated endovascular repair (f-EVAR) between January and September 2014, were reviewed. For each patient, imaging analysis (12 measures: aortic diameters and length and "clock position" of visceral artery) was performed on two different workstations: Aquarius (TeraRecon, San Mateo, CA, USA) and EA-AW. According to a standardized protocol, three endovascular surgeons experienced in aortic endograft planning, performed image analyses and data collection independently. We analyzed an internal assessment between observers (on the Aquarius 3DWS) and an external assessment comparing these results with the planning center (PC) data used to custom the fenestrated endograft of the patients enrolled in this study. Finally, we compared both 3DWS data to determine the accuracy and the reproducibility. A p-value < .05 was considered as statistically significant. Complete agreement between operators was defined as 1.0. RESULTS: Intra- and inter-observer variability (interclass correlation coefficients - ICC: 0.81-.091) was very low and confirmed the reliability of our planners. The ICC comparison between EA-AW and Aquarius was excellent (> 0.8 for both), thus confirming the reproducibility and reliability of the new EA-AW application. Aortic and iliac necks diameters and lengths were similarly reported with both workstations. In our study, the mean difference in distance and orientation evaluation of target vessels evaluated by the two workstations was marginal and has no impact on clinical practice in term of device manufacturing. CONCLUSIONS: We showed that complex EVAR planning can be performed with this new dedicated 3D workstation workflow with a good reproducibility.

Modern diagnostics for type B aortic dissection.

BACKGROUND: Undifferentiated chest pain is one of the most common complaints in the acute care setting. Type B aortic dissection is an important cause of chest pain and a complex clinical entity, which carries significant morbidity and mortality and requires accurate clinical and radiological evaluation. METHODS: Imaging technologies have become an irreplaceable tool to establish the diagnosis of aortic dissection and to plan treatment strategies. Computed tomography is an important component in this process, replacing catheter-based angiography as the most commonly used preoperative and postoperative imaging modality for the thoracic aorta. The use of functional imaging methods, such as magnetic resonance imaging and echocardiography is evolving. These methods are able to provide the clinically relevant anatomical, hemodynamic and biomechanical information that is necessary for accurate diagnosis, risk stratification and patient selection for treatment. CONCLUSION: Advanced image acquisition equipment and expertise are increasingly available in a growing number of institutions and as a consequence, existing strategies for the management of type B dissection are rapidly evolving.

[Risk evaluation of type B aortic dissection: importance for treatment of acute aortic syndrome]. / Risikoevaluation der Aortendissektion Typ B: Bedeutung für die Behandlung des akuten Aortensyndroms.

Acute aortic syndrome (AAS) is a modern term used to describe interrelated emergency aortic conditions with similar clinical characteristics and challenges including aortic dissection, intramural hematoma (IMH) and penetrating aortic ulcer (PAU). Population-based studies suggest that the incidence of aortic dissection ranges from 2.6 to 3.5 cases per 100,000 inhabitants per year; hypertension and a variety of genetic disorders with altered connective tissue are the most prevalent risk conditions. In general, open surgical repair is recommended when dissection involves the ascending aorta, whereas medical management and endovascular stent graft repair is the best option when the ascending aorta is spared. Pathological conditions involving the aortic arch may be treated using a hybrid approach combining debranching of supra-aortic vessels and stent graft placement. Stent graft-induced remodeling of a dissected aorta seems to have long-term benefits in complicated and so-called uncomplicated type B dissections as almost every case reveals a risk profile and one in eight patients diagnosed with acute type B aortic dissection has either an IMH or a PAU. Pain is the most commonly presenting symptom of AAS and should prompt immediate attention including diagnostic imaging modalities, such as multislice computed tomography, transesophageal ultrasound and magnetic resonance imaging. A specific therapeutic approach is necessary for IMH and PAU because without treatment they have a very poor outcome, are unpredictable in evolution and can be more severe than acute aortic dissection. All patients must receive the best medical treatment available at admission. High-risk but asymptomatic patients with IMH and PAU can probably be monitored without interventions. All symptomatic patients will need treatment. In many of these patients a direct surgical approach is often prohibitive due to age and multiple comorbidities. Endovascular treatment offers superior results and is becoming a recognized indication for such patients. Irrespective of the treatment modality close surveillance is mandatory in order to monitor disease progression.

Optimising pre- and postoperative imaging for thoracic aortic pathology.

Thoracic aortic pathology carries significant morbidity and mortality, which requires prompt and accurate clinical and radiological evaluation. Advances in imaging technologies have improved our knowledge of the mechanisms of growth and rupture and our understanding of endovascular repair. Computed tomography has become a crucial component in this process, replacing catheter-based angiography as the most commonly used pre- and postoperative imaging modality for the thoracic aorta. Functional imaging methods such as magnetic resonance and echocardiography are evolving and are able to provide the clinically relevant anatomic, haemodynamic and biomechanical information that is necessary for accurate diagnosis, risk stratification and selection of the appropriate treatment for an individual patient. The availability of advanced image acquisition expertise and equipment is spreading to a growing number of institutions worldwide and will greatly enhance existing imaging strategies for patients with thoracic aortic pathology.

Endovascular repair of acute uncomplicated aortic type B dissection promotes aortic remodelling: 1 year results of the ADSORB trial.

OBJECTIVES: Uncomplicated acute type B aortic dissection (AD) treated conservatively has a 10% 30-day mortality and up to 25% need intervention within 4 years. In complicated AD, stent grafts have been encouraging. The aim of the present prospective randomised trial was to compare best medical treatment (BMT) with BMT and Gore TAG stent graft in patients with uncomplicated AD. The primary endpoint was a combination of incomplete/no false lumen thrombosis, aortic dilatation, or aortic rupture at 1 year. METHODS: The AD history had to be less than 14 days, and exclusion criteria were rupture, impending rupture, malperfusion. Of the 61 patients randomised, 80% were DeBakey type IIIB. RESULTS: Thirty-one patients were randomised to the BMT group and 30 to the BMT+TAG group. Mean age was 63 years for both groups. The left subclavian artery was completely covered in 47% and in part in 17% of the cases. During the first 30 days, no deaths occurred in either group, but there were three crossovers from the BMT to the BMT+TAG group, all due to progression of disease within 1 week. There were two withdrawals from the BMT+TAG group. At the 1-year follow up there had been another two failures in the BMT group: one malperfusion and one aneurysm formation (p = .056 for all). One death occurred in the BMT+TAG group. For the overall endpoint BMT+TAG was significantly different from BMT only (p < .001). Incomplete false lumen thrombosis, was found in 13 (43%) of the TAG+BMT group and 30 (97%) of the BMT group (p < .001). The false lumen reduced in size in the BMT+TAG group (p < .001) whereas in the BMT group it increased. The true lumen increased in the BMT+TAG (p < .001) whereas in the BMT group it remained unchanged. The overall transverse diameter was the same at the beginning and after 1 year in the BMT group (42.1 mm), but in the BMT+TAG it decreased (38.8 mm; p = .062). CONCLUSIONS: Uncomplicated AD can be safely treated with the Gore TAG device. Remodelling with thrombosis of the false lumen and reduction of its diameter is induced by the stent graft, but long term results are needed.

Pathology specific early outcome after thoracic endovascular aortic repair.

OBJECTIVES: Endovascular intervention is established for treatment of thoracic aortic dissection and aneurysm. The aim of this study was to compare the incidence of all-cause and aortic-related in-hospital mortality, stroke, spinal cord ischaemia, and major adverse event rate for patients undergoing thoracic aortic endovascular intervention to see if there is a pathology-specific effect. METHODS: Data were collected prospectively and analysed retrospectively for a cohort of 309 consecutive patients with either thoracic aortic dissection or aneurysm over a 14-year period. RESULTS: There were 209 men and 100 women with a median age of 72 years (interquartile range [IQR] 63-78 years). Aneurysm affected 62% (193/309) of patients and 37% (116/309) had complicated type B aortic dissection, of whom 43% (50/116) had acute and 57% (66/116) chronic presentations. In patients with aortic dissection compared to aneurysm, there was no significant difference in all-cause in-hospital mortality (6.9% vs. 8.3% respectively, p = 0.827, relative risk [RR] 0.83, 95% confidence interval [CI] 0.37-1.88), stroke (6.0% vs 6.2%, p = 1.00, RR 0.971, CI 0.39-2.39), spinal cord ischaemia (6.0% vs 6.2%, p = 1.00, RR 1.030, CI 0.42-2.54), or major adverse event rate (16.4% vs. 16.6%, p = 1.00, RR 0.988, CI 0.59-1.66). The rate of aortic related death was four times greater in the dissection than in the aneurysm group (4/8 = 50% vs 2/16 = 12.5%, p = 0.06, RR 6.99, CI 0.92-52.5) although this did not reach statistical significance. CONCLUSIONS: There was no difference in the incidence of in-hospital mortality, stroke, and spinal cord ischaemia between aneurysm and dissection. The higher rate of aortic related death in the dissection group may indicate the need to refine the clinical management of these patients, including procedural planning, endograft design, and operative technique.

Uncomplicated type B dissections: which patients should be treated? Lessons learned from the recent literature.

The management of type B aortic dissection is complex and decision-making is often based on physician experience and subjective clinical judgment. Thoracic endovascular aortic repair is considered first-line therapy for complicated type B aortic dissection but whether this should be performed in uncomplicated cases has been a matter of debate. Randomized controlled trials have demonstrated the long-term benefit of endovascular treatment to prevent aortic-related mortality, however pre-emptive surgery may not be the solution for all patients because of the occurrence of adverse events such death, stroke and paraplegia. Morphological and false lumen characteristics including aortic diameter, the position, size and number of entry tears and false lumen thrombus volume have been shown to serve as predictors of outcome and may be used to identify high-risk patients. Functional imaging methods such as magnetic resonance and echocardiography are evolving and may be able to provide the clinically-relevant structural, hemodynamic and biomechanical information that is needed for accurate risk stratification of individual patients. A patient-specific approach designed to intervene only in patients that are at high risk of developing complications should improve the long-term outcome of these patients.

A 14-year experience with aortic endograft infection: management and results.

OBJECTIVES: The management of thoracic and abdominal aortic endograft infection is complex and associated with high mortality. Cases are rare: a recent systematic review identified 117 reported cases; the largest reported series comprises 12 infected endografts. METHODS: We report 22 consecutive patients with infected abdominal or thoracic aortic endovascular devices implanted from 1998 to 2012. Management included extension with new devices, aneurysm sac drainage of pus/irrigation with antibiotics, endograft explantation, and axillo-(bi)femoral reconstruction. RESULTS: Twenty-two patients (16 men) were identified. Median age was 71 years (range, 43-88 years). Index devices were infra-renal endovascular repair (n = 13), and thoracic endovascular repair (n = 9) all for aneurysmal or pseudoaneurysmal disease. Seven (32%) had prior aortic surgery. Follow-up was complete in all cases; in survivors follow-up was a median of 29 (range, 12-45) months. The mortality from explantation of ten infra-renal devices was 1/10 (10%) on-table and a further 2/10 (20%) within 30 days. Device retention led to disease progression and death in all patients with infected endografts. Sac drainage/irrigation provided only temporary control of sepsis. Device extension can treat rupture, but additional devices became infected. CONCLUSION: Abdominal endograft explantation is high risk but may be curative. Appropriate selection of patients for infected endograft explantation remains a major challenge.

Hybrid repair of complex thoracic aortic arch pathology: long-term outcomes of extra-anatomic bypass grafting of the supra-aortic trunk.

PURPOSE: Hybrid repair constitutes supra-aortic debranching before thoracic endovascular aortic repair (TEVAR). It offers improved short-term outcome compared with open surgery; however, longer-term studies are required to assess patient outcomes and patency of the extra-anatomic bypass grafts. METHODS: A prospectively maintained database of 380 elective and urgent patients who had undergone TEVAR (1997-2011) was analyzed retrospectively. Fifty-one patients (34 males; 17 females) underwent hybrid repair. Median age was 71 (range, 18-90) years with mean follow-up of 15 (range, 0-61) months. RESULTS: Perioperative complications included death: 10 % (5/51), stroke: 12 % (6/51), paraplegia: 6 % (3/51), endoleak: 16 % (8/51), rupture: 4 % (2/51), upper-limb ischemia: 2 % (1/51), bypass graft occlusion: 4 % (2/51), and cardiopulmonary complications in 14 % (7/51). Three patients (6 %) required emergency intervention for retrograde dissection: (2 aortic root repairs; 2 innominate stents). Early reintervention was performed for type 1 endoleak in two patients (2 proximal cuff extensions). One patient underwent innominate stenting and revision of their bypass for symptomatic restenosis. At 48 months, survival was 73 %. Endoleak was detected in three (6 %) patients (type 1 = 2; type 2 = 1) requiring debranching with proximal stent graft (n = 2) and proximal extension cuff (n = 1). One patient had a fatal rupture of a mycotic aneurysm and two arch aneurysms expanded. No bypass graft occluded after the perioperative period. CONCLUSIONS: Hybrid operations to treat aortic arch disease can be performed with results comparable to open surgery. The longer-term outcomes demonstrate low rates of reintervention and high rates of graft patency.

Predictors of outcome after endovascular repair for chronic type B dissection.

OBJECTIVES: To assess the durability of endovascular repair (TEVAR) in chronic type B dissection (CD) and identify factors predictive of outcome. DESIGN: Retrospective analysis of a prospective database. MATERIALS: Patients undergoing TEVAR for CD at a tertiary referral centre 2000-2010. METHODS: Analysis of pre-operative characteristics, operative outcome, false lumen thrombosis, aortic diameter and survival. RESULTS: 58 consecutive patients were included (49 elective, 9 urgent, mean age 66 years). Mean aortic diameter was 6.4 cm (Standard deviation SD 1.3 cm). Three patients died perioperatively (5%, 1 urgent, 2 elective). Complications included retrograde type A dissection (n = 3), paraplegia (1), and transient ischaemic attack (1). Estimated survival (Kaplan-Meier) was 89% (1-year) and 64% (3-years). Forty-seven patients had mid-term imaging follow-up at mean 38 months. Reintervention rate was 15% at 1-year and 29% at 3-years. Aortic diameter decreased in 24, was stable in 15 and increased in 8. Mid-term survival was higher in patients with aortic remodelling (reduction of aortic diameter >0.5 cm; 3-year 89%) than without (54%; Log Rank p = 0.005). Remodelling occurred with extensive false lumen thrombosis. CONCLUSION: Satisfactory mid-term outcome after TEVAR for CD remains a challenge. Survival is associated with aortic remodelling, which is related to persistence of flow in the false lumen.

Nonrigid motion modeling of the liver from 3-D undersampled self-gated golden-radial phase encoded MRI.

Magnetic resonance imaging (MRI) has been commonly used for guiding and planning image guided interventions since it provides excellent soft tissue visualization of anatomy and allows motion modeling to predict the position of target tissues during the procedure. However, MRI-based motion modeling remains challenging due to the difficulty of acquiring multiple motion-free 3-D respiratory phases with adequate contrast and spatial resolution. Here, we propose a novel retrospective respiratory gating scheme from a 3-D undersampled high-resolution MRI acquisition combined with fast and robust image registrations to model the nonrigid deformation of the liver. The acquisition takes advantage of the recently introduced golden-radial phase encoding (G-RPE) trajectory. G-RPE is self-gated, i.e., the respiratory signal can be derived from the acquired data itself, and allows retrospective reconstructions of multiple respiratory phases at any arbitrary respiratory position. Nonrigid motion modeling is applied to predict the liver deformation of an average breathing cycle. The proposed approach was validated on 10 healthy volunteers. Motion model accuracy was assessed using similarity-, surface-, and landmark-based validation methods, demonstrating precise model predictions with an overall target registration error of TRE = 1.70 ± 0.94 mm which is within the range of the acquired resolution.

Total endovascular repair of thoracoabdominal aortic aneurysms.

BACKGROUND: Endovascular graft designs incorporating sidebranches, fenestrations and scallops offer a minimally-invasive alternative to open surgery and hybrid approaches for thoracoabdominal aortic aneurysms (TAAA). Our unit has offered total endovascular TAAA repair to selected higher-risk patients since 2008. We report the largest UK series to date of total endovascular TAAA repair. METHODS: Retrospective analysis of a prospectively-maintained operative database. RESULTS: 31 patients (21 male, 10 female) median age 71 years (range 58-84), with TAAA (12 Crawford type I, 13 type III, 6 type IV), median diameter 6.4 (4.3 (mycotic)- 9.9) underwent endovascular TAAA repair (total 48 sidebranches, 26 fenestrations, 13 scallops) between July 2008 and January 2011. Median operating time 225 min (65-540 min), X-ray screening time 58 min (4-212 min), contrast dose 175 ml (70-500 ml), blood loss 325 ml (100-400 ml). Median post-operative length of hospital stay 6 days (2-22 days). Three patients (3/31, 9.7%) died within 30 days of operation: multisystem organ failure (1) acute renal failure and paraplegia (1) and paraplegia (1). There were no other cases of in-hospital organ failure, paraplegia or major complications. The median change in pre-discharge from pre-operative renal function was 3.4% deterioration in eGFR (range: 32.7% deterioration to 73.0% improvement) One patient presented with late-onset paraparesis, a second developed acute renal failure 8 months after repair. One early high-pressure endoleak (type 3) required correction. Three patients had died by median follow-up 12 months (1-36), 2 from heart disease and one from haemopericardium secondary to acute dissection of the ascending aorta (the dissection did not involve, nor extend close to, the endovascular graft). CONCLUSIONS: Total endovascular repair of TAAA offers patients a minimally-invasive alternative to open surgery with early results at least comparable to those seen with open or hybrid surgical approaches.

Predictors of stroke and paraplegia in thoracic aortic endovascular intervention.

BACKGROUND: Endoluminal repair of thoracic aortic pathology has become established in clinical practice, but is associated with significant neurological complications. The aim of this study was to identify factors that were predictive of stroke and paraplegia. METHODS: Prospective data was collected for a cohort of 293 consecutive patients having thoracic aortic endovascular repair between August 1997 and September 2009. Patient and procedural characteristics were related to the incidence of stroke and paraplegia using multivariate logistic regression analysis. RESULTS: The median age was 68 years (18-87), there were 191 men and 102 women. Mortality was 5.1% for 195 elective and 13.4% for 98 urgent patients. Stroke affected 16 (5.5%) patients: 11 affected the anterior and 5 the posterior circulation. Coverage of the left subclavian artery with no revascularisation was the only significant factor predictive of stroke (OR 5.34 (1.42-20.40) P = 0.01). Paraplegia affected 16 patients (5.5%) but no independent risk factor was identified: 12 were identified perioperatively and 4 were delayed by up to 6 months. CONCLUSION: Covering the left subclavian artery without revascularisation increases the risk of stroke following endoluminal repair of thoracic pathology. Paraplegia appears to be more complex and no independent precipitating factor was identified.