Computational prediction of proximal sealing in endovascular abdominal aortic aneurysm repair with unfavorable necks.

BACKGROUND AND OBJECTIVE: Endovascular aortic aneurysm repair (EVAR) has become the standard treatment for abdominal aortic aneurysms in most centers. However, proximal sealing complications leading to endoleaks and migrations sometimes occur, particularly in unfavorable aortic anatomies and are strongly dependent on biomechanical interactions between the aortic wall and the endograft. The objective of the present work is to develop and validate a computational patient-specific model that can accurately predict these complications. METHODS: Based on pre-operative CT-scans, we developed finite element models of the aorta of 10 patients who underwent endovascular aortic aneurysm repair, 7 with standard morphologies and 3 with unfavorable anatomies. We simulated the deployment of stent grafts in each aorta by solving mechanical equilibrium with a virtual shell method. Eventually we compared the actual stent ring positions from post-operative computed-tomography-scans with the predicted simulated positions. RESULTS: A successful deployment simulation could be performed for each patient. Relative radial, transverse and longitudinal deviations were 6.3 ± 4.4%, 2.5 ± 0.9 mm and 1.4 ± 1.1 mm, respectively. CONCLUSIONS: The numerical model predicted accurately stent-graft positions in the aortic neck of 10 patients, even in complex anatomies. This shows the potential of computer simulation to anticipate possible proximal endoleak complications before EVAR interventions.

Ruptured infective native thoracic aortic aneurysm treated by endovascular repair as a bridge therapy to open repair.

We report the case of a 70-year-old woman who presented with a ruptured infective native thoracic aortic aneurysm (INTAA), associated with spondylodiscitis and posterior mediastinitis. She underwent a staged hybrid repair: urgent thoracic endovascular aortic repair was first performed as a bridge therapy in the context of septic shock. Allograft repair using cardiopulmonary bypass was performed five days later. Given the complexity of INTAA, multidisciplinary teamwork was paramount to determine the most appropriate treatment strategy, including procedure planning with multiple operators as well as perioperative care. Therapeutic alternatives are discussed.

Prehospital triage of acute aortic syndrome using a machine learning algorithm.

BACKGROUND: Acute aortic syndrome (AAS) comprises a complex and potentially fatal group of conditions requiring emergency specialist management. The aim of this study was to build a prediction algorithm to assist prehospital triage of AAS. METHODS: Details of consecutive patients enrolled in a regional specialist aortic network were collected prospectively. Two prediction algorithms for AAS based on logistic regression and an ensemble machine learning method called SuperLearner (SL) were developed. Undertriage was defined as the proportion of patients with AAS not transported to the specialist aortic centre, and overtriage as the proportion of patients with alternative diagnoses but transported to the specialist aortic centre. RESULTS: Data for 976 hospital admissions between February 2010 and June 2017 were included; 609 (62·4 per cent) had AAS. Overtriage and undertriage rates were 52·3 and 16·1 per cent respectively. The population was divided into a training cohort (743 patients) and a validation cohort (233). The area under the receiver operating characteristic (ROC) curve values for the logistic regression score and the SL were 0·68 (95 per cent c.i. 0·64 to 0·72) and 0·87 (0·84 to 0·89) respectively (P < 0·001) in the training cohort, and 0·67 (0·60 to 0·74) and 0·73 (0·66 to 0·79) in the validation cohort (P = 0·038). The logistic regression score was associated with undertriage and overtriage rates of 33·7 (bootstrapped 95 per cent c.i. 29·3 to 38·3) and 7·2 (4·8 to 9·8) per cent respectively, whereas the SL yielded undertriage and overtriage rates of 1·0 (0·3 to 2·0) and 30·2 (25·8 to 34·8) per cent respectively. CONCLUSION: A machine learning prediction model performed well in discriminating AAS and could be clinically useful in prehospital triage of patients with suspected AAS.

ANTECEDENTES: Los síndromes aórticos agudos (aortic acute syndromes, AAS) constituyen un grupo complejo y potencialmente letal de entidades que requieren un tratamiento especializado en emergencias. El objetivo de este estudio fue construir un algoritmo de predicción para ayudar a la selección prehospitalaria de los AAS. MÉTODOS: Se recogieron prospectivamente una serie de pacientes consecutivos inscritos en una red regional especializada en patología aórtica. Se desarrollaron dos algoritmos de predicción para AAS basados en una regresión logística y en un método de aprendizaje automático denominado Super Learner (SL). Undertriage (infra-selección) se definió como la proporción de pacientes con AAS no transportados al centro especializado en patología aórtica y el overtriage (sobre-selección) como la proporción de pacientes con diagnósticos alternativos al AAS pero transportados al centro especializado en patología aórtica. RESULTADOS: Se incluyeron los datos de 976 ingresos hospitalarios entre febrero de 2010 y junio de 2017, con 609 (62,4%) AAS. Las tasas de overtriage y undertriage fueron del 52,3% y del 16,1%, respectivamente. La población se dividió en una cohorte de entrenamiento (n = 743) y en una cohorte de validación (n = 233). El área bajo la curva ROC para la puntuación de regresión logística y el SL fueron de 0,68 (0,64, 0,72) y de 0,87 (0,84, 0,89), respectivamente (P < 0,001) en la cohorte de entrenamiento, y de 0,67 (0,60, 0,74) y de 0,73 (0,66, 0,79) en la cohorte de validación (P = 0,038). La puntuación de regresión logística se asoció con tasas de undertriage y overtriage de 33,7% (i.c. del 95% bootstrapped 29,3%, 38,3%) y de 7,2% (4,8%, 9,8%), respectivamente, mientras que el SL presentó tasas de undertriage y overtriage de 1,0% (0,3%, 2,0%) y de 30,2% (25,8%, 34,8%), respectivamente. CONCLUSIÓN: El modelo de predicción de aprendizaje automático funcionó bien para discriminar AAS y podría ser clínicamente útil en la selección prehospitalaria de pacientes con sospecha de síndrome aórtico agudo.

Open Conversion After Endovascular Abdominal Aneurysm Repair: An 8 year Single Centre Experience.

OBJECTIVE: To report experience with open conversion (OC) after previous failed EVAR and to compare outcomes of patients undergoing elective OC with those operated on in an urgent setting. METHODS: Patients undergoing OC after EVAR between August 2008 and September 2016 were included in this retrospective and observational single institution study. Indications, demographic, anatomical, intra-operative and post-operative data were collected prospectively. Primary endpoints were 30 day and in hospital mortality. Secondary endpoints included moderate to severe complications, secondary interventions, length of intensive care unit, and hospital stay. RESULTS: OC was performed in 31 patients over the study period: 19 elective and 12 emergency OC, including six ruptures. Median time from index EVAR to delayed OC was 35 months (0-228 months). The most common indications for OC were endoleaks (n = 24, 77%), followed by stent graft infection (n = 3, 10%), thrombosis (n = 3, 10%) and kinking (n = 1, 3%). Eight of the removed stent grafts were Endurant, two were Talent, five Excluder, six Nellix, two AFX, five Zenith, one Vanguard, one Anaconda, and one Seta. Overall in hospital mortality was 10%, with significantly increased in hospital mortality in the emergency group compared with the elective group (25% vs. 0%, p = .049). Renal and pulmonary complications were significantly higher in the emergency group (42% vs. 5%, p = .02 and 42% vs. 0%, p = .005, respectively). No late complication or death was recorded after a mean follow-up of 18 ± 13 months. CONCLUSIONS: Emergency OC is associated with significantly increased in hospital mortality and morbidity compared with elective OC. Elective OC appears to be safer and effective, and should be considered as the best option in cases of EVAR failure to avoid further emergency OC procedures.

[Therapeutic endovascular procedures in aortitis]. / Place du traitement endovasculaire dans les aortites inflammatoires.

Aortitis is an inflammation of the aortic wall with an infectious or non-infectious origin, which often progresses to vascular complications. The open surgical approach is a high-risk procedure for these pathologies. Endovascular interventions have improved the prognosis of patients with aortitis complications. This manuscript describes the pathophysiology responsible for vascular complications and the role of endovascular approach for their treatment.

Proximal Scallop in Thoracic Endovascular Aortic Aneurysm Repair to Overcome Neck Issues in the Arch.

OBJECTIVE: To evaluate initial experience with a custom made proximal scalloped stent graft for thoracic endovascular aortic repair (TEVAR) of aortic aneurysms involving the arch. METHODS: Between September 2012 and November 2014, patients presenting with a thoracic aortic aneurysm (TAA) with short or angulated neck were selected for treatment by custom made proximal scalloped Relay Plus stent grafts (ABS Bolton Medical, Barcelona, Spain). Prospectively acquired data relating to patient demographics, procedure details, clinical outcomes, and complications were analyzed retrospectively. RESULTS: Ten selected patients (50% male, mean age 77 ± 8 years) were treated using a thoracic custom made Relay Plus stent graft, three of whom underwent additional cervical supra-aortic trunk revascularizations. TAA were fusiform in four cases, saccular in three, and three patients were treated for proximal type I endoleaks after previous standard TEVAR. The graft was landed in zone 2 in 3 cases, in zone 1 in 4 cases, and in zone 0 in 3 cases. The custom made scallop was designed to preserve flow in the left subclavian artery in three patients, in the left common carotid artery in four, and in the innominate artery in three. No proximal type I endoleak occurred and proximal sealing was achieved in all cases, with a technical success rate of 100%. All targeted vessels were patent. During a mean follow up of 12 ± 5 months, no conversion to open surgical repair and no aortic rupture occurred. One patient died post-operatively from myocardial infarction and one patient suffered a stroke with complete recovery. One patient had a distal type I endoleak on the 6 month CT scan and is scheduled for distal extension. No paraplegia, retrograde dissection and no other aortic related complications were recorded. CONCLUSIONS: Proximal scalloped stent grafts appear to be an effective additional tool for TEVAR of TAA when dealing with short or angulated proximal necks.

[Peripheral artery occlusive disease of the lower limbs: Rapid aggravation in a patient taking nilotinib for chronic myeloid leukemia]. / Artériopathie des membres inférieurs d'aggravation rapide chez un patient traité par nilotinib pour leucémie myéloïde chronique.

The development of tyrosine kinase inhibitors (TKI) has revolutionized management of patients with chronic myeloid leukemia (CML), transforming this fatal disease into a chronic disease with nearly normal life expectancy. Nilotinib is a second generation TKI targeting the oncoprotein BCR-ABL used in patients in the chronic phase of CML. Several research teams have suggested over recent years that nilotinib might be the causal agent in the development or aggravation of vascular disease, particularly in patients with cardiovascular risk factors or an established cardiovascular disease. We report here the case of a patient who developed severe peripheral arterial disease of the lower limbs that worsened despite optimal medical and surgical care, presenting recurrent re-stenoses after different revascularization techniques (bypass, angioplasty…) associated with aggravation of severe trophic disorders to the point of potentially requiring amputation. Discontinuation of nilotinib enabled a stabilization of the arterial lesions and complete healing of the trophic lesions. This case illustrates the importance of recognizing co-morbid conditions in patients with severe vascular disease and to examine the possibility of drug interactions leading to rapid aggravation of arterial disease with no other cause. Studying the pathophysiological impact of TKIs on the vascular system may open new avenues of research for the investigation of factors triggering arteriosclerosis.

Editor's Choice - ECAR (Endovasculaire ou Chirurgie dans les Anévrysmes aorto-iliaques Rompus): A French Randomized Controlled Trial of Endovascular Versus Open Surgical Repair of Ruptured Aorto-iliac Aneurysms.

OBJECTIVES/BACKGROUND: ECAR (Endovasculaire ou Chirurgie dans les Anévrysmes aorto-iliaques Rompus) is a prospective multicentre randomized controlled trial including consecutive patients with ruptured aorto-iliac aneurysms (rAIA) eligible for treatment by either endovascular (EVAR) or open surgical repair (OSR). Inclusion criteria were hemodynamic stability and computed tomography scan demonstrating aorto-iliac rupture. METHODS: Randomization was done by week, synchronously in all centers. The primary end point was 30 day mortality. Secondary end points were post-operative morbidity, length of stay in the intensive care unit (ICU), amount of blood transfused (units) and 6 month mortality. RESULTS: From January 2008 to January 2013, 107 patients (97 men, 10 women; median age 74.4 years) were enrolled in 14 centers: 56 (52.3%) in the EVAR group and 51 (47.7%) in the OSR group. The groups were similar in terms of age, sex, consciousness, systolic blood pressure, Hardman index, IGSII score, type of rupture, use of endoclamping balloon, and levels of troponin, creatinine, and hemoglobin. Delay to treatment was higher in the EVAR group (2.9 vs. 1.3 hours; p < .005). Mortality at 30 days and 1 year were not different between the groups (18% in the EVAR group vs. 24% in the OSR group at 30 days, and 30% vs. 35%, respectively, at 1 year). Total respiratory support time was lower in the EVAR group than in the OSR group (59.3 hours vs. 180.3 hours; p = .007), as were pulmonary complications (15.4% vs. 41.5%, respectively; p = .050), total blood transfusion (6.8 vs. 10.9, respectively; p = .020), and duration of ICU stay (7 days vs. 11.9 days, respectively; p = .010). CONCLUSION: In this study, EVAR was found to be equal to OSR in terms of 30 day and 1 year mortality. However, EVAR was associated with less severe complications and less consumption of hospital resources than OSR.

[Massive hemoptysis following thoracic aortic rupture: an advancing field]. / Hémoptysie massive survenue après traitement endovasculaire d'un anévrisme aortique. Une prise en charge en pleine évolution.

We report the case of a 57-year-old woman who presented with massive hemoptysis and thoracic pain 3 years after the endovascular treatment of a thoracic aortic aneurysm. Emergency work up revealed the presence of an endoleak, leading to the pressurization of the aneurysm sac and its subsequent rupture into the lung parenchyma. The discussion includes presentation, clinical course, diagnosis, complications and new therapeutic options in the management of a massive hemoptysis secondary to aortic rupture. All together, the case and discussion highlight the classical rules of critical care and the recent advances in endovascular treatment of thoracic aortic rupture.

Downregulation of remodelling enzymatic activity induced by an angiotensin-converting enzyme inhibitor (perindopril) reduces the degeneration of experimental abdominal aortic aneurysms in a rat model.

AIMS: Angiotensin-converting enzyme (ACE) inhibitors have proven their ability to affect vascular wall remodelling, in addition to their anti-hypertensive effects. The aim of this study was to assess the impact of perindopril on the development of abdominal aortic aneurysm (AAA) in a rat model, and its correlation to enzyme activities involved in vascular wall remodelling. METHODS: The model of the decellularised aortic xenograft in Lewis rat was chosen. Rats were randomised to two groups: group P fed with 3 mg kg(-1) of perindopril daily during 30 days, or control group C (n = 15 per group)). Rats were euthanised at 30 days for analysis. AAA growth and histological changes in the aortic wall were measured by histomorphometry. Proteolytic activities were measured by gelatin zymography of conditioned medium for activematrix metalloproteinase 9/pro-matrix metalloproteinase 9 (MMP9/pro-MMP9) and activeMMP2/pro-MMP2, and by quantitative immunofluorescence tissue for elastase and plasmin. RESULTS: The mean maximal diameter of AAAs at 30 days was significantly lower in the treated group P compared with the control group C (2.5 ± 1.0 vs. 4.9 ± 2.1 mm; P < 0.01). The expansion rate of AAAs after 30 days was significantly reduced in group P compared with group C (36 ± 14% vs. 67 ± 23%; P < 0.01). Pro-MMP9 and MMP9 activities were significantly decreased in relative intensity (RI) in group P compared with group C (0.43 ± 0.64 RI vs. 1.02 ± 0.61 RI, P = 0.01; 0.18 ± 0.57 RI vs. 0.66 ± 1.19 RI, P = 0.004). The activation rate of MMP2 was also significantly lower in group P compared with group C (1.27 ± 0.42 vs. 1.67 ± 0.44; P = 0.002). Elastase and plasmin tissue activities were significantly lower in group P compared with group C, respectively (3.9 ± 3.3 vs. 5.8 ± 3.7 IF min(-1) g(-1),and 25.9 ± 23.9 vs. 49.1 ± 38.7 IF min(-1) g(-1); P < 0.05). CONCLUSION: After 30 days of treatment by perindopril, a significant decrease in aneurysmal degeneration of the decellularised aortic xenograft AAA model was observed. This phenomenon appears to be induced by a downregulation of enzymes involved in the aortic wall remodelling during aneurysmal degeneration.

[Acute traumatic rupture of the aortic isthmus]. / Rupture aiguë post-traumatique de l'isthme aortique.

Traumatic rupture of the aortic isthmus is a rare lesion occurring in patients subjected to violent deceleration. Because of the forces involved, it is frequently associated with concomitant life-threatening injuries. Non-invasive examinations such as CT and transesophageal echocardiography aid greatly in making the diagnosis. Urgent conventional repair is still considered the gold standard technique for cases of isolated rupture, or rupture without severe concomitant lesion where aortic clamping and heparinization will not impair post-operative outcomes. Urgent endovascular repair has been shown to be a feasible and efficient technique which may be proposed as a therapeutic option for patients with multiple trauma instead of delayed classical surgical repair after stabilization. Long-term results of endovascular repair need to be assessed before enlarging the indications of this technique in the emergency setting.

Four-part fracture after intrathoracic displacement of the humeral head: a case report and review of the literature.

Displaced four-part fracture dislocation represents the highest risk of osteonecrosis of the humeral head due to a disruption of the blood supply. In a few cases, that dislocation can be intrathoracic which worsens prognosis with life-threatening injuries such as hemothorax or pneumothorax. This paper presents the case of a 77-year-old woman after having fallen down the stairs with an intrathoracic dislocation four-part fracture leaving the head in the thorax. We analyze mechanisms and review the literature in order to highlight this lesion and provide a take home message for the treatment.

Emergency endovascular repair for ruptured abdominal aortic aneurysms: feasibility and comparison of early results with conventional open repair.

PURPOSE: To assess the feasibility of endovascular aortic repair (EVAR) on patients presenting with a ruptured abdominal aortic aneurysm (AAA) in a teaching hospital, and to compare there post-operative outcomes with contemporaneous patients treated with open repair (OR). METHODS: A series of consecutive of patients presenting ruptured AAA with retro/intraperitoneal haematoma were included in the study. EVAR was attempted whenever possible. In all other cases (severe haemodynamic instability, adverse anatomy, device unavailability), ruptured AAA were treated by OR. RESULTS: Thirty-seven patients were enrolled between January 2001 and July 2004. Seventeen (46%) patients were treated using adapted designed aortoiliac endografts (eight bifurcated, eight aorto-uniiliac, one iliac extension). Twenty (54%) patients unfit for EVAR because of severe haemodynamic instability (n=8), adverse anatomical configuration (n=7), or unavailability of an appropriate endograft (n=5) were treated by OR. Twenty-seven (73%) had a retrospective suitable anatomy for EVAR. Three early conversions from EVAR to OR were performed. Blood loss, operating time, and intensive care stay were significantly decreased in EVAR patients (respectively: 156 min+/-60, 1520 ml+/-1175, 3 days for EVAR; vs. 222 min+/-82, 3075 ml+/-1750, 13 days for OS; P<.01). The 30-day mortality rate was 23.5% for EVAR vs. 50% for OR (P=0.09). CONCLUSION: EVAR of ruptured AAA is feasible for selected patients based on haemodynamic and morphologic criteria, and should be associated with improved immediate outcomes as compared with OR. These results should be tempered by the fact that these patients have heavy comorbidities which explains the absence of difference in mid-term mortality rates between the two groups, but should also encourage surgical institutions that are managing such life-threatening emergencies to introduce EVAR as part of their therapeutic arsenal for ruptured AAA.

Endovascular repair for ruptured AAA: a literature review.

The reduced physiological impact of endovascular aneurysm repair (EVAR) compared with conventional open repair has been demonstrated. If this technique could be used routinely in patients with ruptured abdominal aortic aneurysm (AAA) it may reduce the high peri-operative mortality. This review of the literature identified the current experience with EVAR of ruptured AAA. Only a small number of case series with selected patients are reported. These patients were selected for their haemodynamic stability, and their suitable aneurysm morphology. The overall anatomic suitability rates for EVAR reported, suggest an applicability of 58% to 80% from an intent-to-treat experience. The average post-operative mortality rate was 24%, ranging from 9 to 45% and may reflect increasing experience and patient selection. Important lessons have been learned from these first experiences that help to define a clear position of EVAR as an additional therapeutic option for ruptured AAA.

Short- and long-term outcome following endovascular aneurysm repair. How does it compare to open surgery?

The primary objective of aneurysm repair is to prevent aneurysm rupture while avoiding aneurysm-related death. This manuscript reviews the primary and secondary outcome measures following endovascular aneurysm repair (EVAR) in relation to similar outcome measures for open surgical repair. Both EVAR and open repair are effective in preventing aneurysm rupture, although late ruptures can occur with either treatment method. The late risk of rupture following EVAR is less that 1% per year using current endovascular devices. Aneurysm-related death rate appears to be lower following EVAR compared to open surgery, primarily due to a lower perioperative mortality rate. Actuarial 5-year survival after both endovascular and open aneurysm repair is approximately 70%. Perioperative outcome measures favor EVAR over open repair for patients with suitable anatomy with reduced morbidity and more rapid patient recovery. Short and long-term outcomes following endovascular repair compare favorably to open repair. However, prospective studies are needed to better define the long-term outcomes using comparable endpoints.