Abdominal aortic aneurysm (AAA) growth is a complex process that is incompletely understood. Significant heterogeneity in growth trajectories between patients has led to difficulties in accurately modeling aneurysm growth across cohorts of patients. We set out to compare four models of aneurysm growth commonly used in the literature and confirm which best fits the patient data of our AAA cohort. Patients with AAA were included in the study if they had two or more abdominal ultrasound scans greater than 3 months apart. Patients were censored from analysis once their AAA exceeded 5.5 cm. Four models were applied using the R environment for statistical computing. Growth estimates and goodness of fit (using the Akaike Information Criterion, AIC) were compared, with p-values based on likelihood ratio testing. Of 510 enrolled patients, 264 met the inclusion criteria, yielding a total of 1861 imaging studies during 932 cumulative years of surveillance. Overall, growth rates were: (1) 0.35 (0.31,0.39) cm/yr in the growth/time calculation, (2) 0.056 (0.042,0.068) cm/yr in the linear regression model, (3) 0.19 (0.17,0.21) cm/yr in the linear multilevel model, and (4) 0.21 (0.18,0.24) cm/yr in the quadratic multilevel model at time 0, slowing to 0.15 (0.12,0.17) cm/yr at 10 years. AIC was lowest in the quadratic multilevel model (1508) compared to other models (P < 0.0001). AAA growth was heterogeneous between patients; the nested nature of the data is most appropriately modeled by multilevel modeling techniques.

In the past decade, thoracic endovascular aortic repair (TEVAR) has become the primary treatment option in descending aneurysm and dissection. The clinical outcome of this minimally invasive technique is strictly related to an appropriate patient/stent graft selection, hemodynamic interactions, and operator skills. In this context, a quantitative assessment of the biomechanical stress induced in the aortic wall due to the stent graft may support the planning of the procedure. Different techniques of medical imaging, like computed tomography or magnetic resonance imaging, can be used to evaluate dynamics in the thoracic aorta. Such information can also be combined with dedicated patient-specific computer-based simulations, to provide a further insight into the biomechanical aspects. In clinical practice, computational analysis might show the development of aortic disease, such as the aortic wall segments which experience higher stress in places where rupture and dissection may occur. In aortic dissections, the intimal tear is usually located at the level of the sino-tubular junction and/or at the origin of the left subclavian artery. Besides, computational models may potentially be used preoperatively to predict stent graft behavior, virtually testing the optimal stent graft sizing, deployment, and conformability, in order to provide the best endovascular treatment. The present study reviews the current literature regarding the use of computational tools for TEVAR biomechanics, highlighting their potential clinical applications.

To evaluate the feasibility and the safety of performing urgent (within 24 hours) carotid endarterectomy in patients with carotid stenosis presenting with repetitive transient ischemic attacks or progressing stroke. Thirty consecutive patients underwent urgent carotid endarterectomy for repetitive transient ischemic attacks (N = 12) or progressing stroke (N = 18) according to the following criteria: two or more transient ischemic attacks or a fluctuating neurological deficit over a period of less than 24 hours (progressing stroke), no impairment of consciousness, no cerebral infarct larger than 1.5 cm in diameter on computed tomography and a carotid artery stenosis of 70% or more on the appropriate side, diagnosed by echodoppler ultrasonography and/or arteriography. Patients with cerebral hemorrhage were excluded. All patients were examined pre- and postoperatively by the same neurologist and surgery was performed by the same vascular surgeon. All the patients underwent a cerebral CT scan within 5 days after surgery. There were 19 men and 11 women. The mean age was 71 ± 7.6 years. The time delay of surgery after the onset of transient ischemic attacks or progressing stroke averaged 19.4 ± 11.5 hours. For patients suffering progressive stroke, one developed a fatal ischemic stroke 24 hours after surgery, five showed no improvement of their neurological status after surgery, but none worsened. Twelve patients experienced significant improvement of their neurological status with an European Stroke Scale of 77.9 ± 25.2 at admission and 95.8 ± 4.6 at discharge, and all but one of those patients had a Barthel's index value over 85/100 at discharge. The 12 patients with repetitive transient ischemic attacks had an uneventful postoperative outcome. The mean duration of follow-up was 3.4 ± 1.2 years. No patient developed another transient ischemic attack or ischemic stroke during the follow-up period. The results of our series documented the feasibility and the safety of performing urgent (within 24 hours) carotid endarterectomy in patients presenting with repetitive transient ischemic attacks or progressing stroke. This procedure seems to us to be justified by the fact that waiting for surgery may lead to the development of a more profound deficit or another stroke in these neurologically unstable patients whose only chance for neurological recovery is in the early phase.

Aortic dissection occurs in about 5% of patients with coexistent abdominal aortic aneurysm (AAA); combined type B dissection complicated with visceral malperfusion and AAA is an uncommon aortic emergency and patients presenting with complications of thoracic aortic dissection have a dismal prognosis related to difficulties in treatment strategies. Despite tremendous improvement of endovascular techniques, surgical aortic fenestration represents a quick, safe, and effective procedure able to restore flow in an otherwise malperfused aorta. This procedure has to be kept in mind because subsets of patients cannot be treated conventionally due to either prohibitive risk of aortic replacement, anatomic contraindication, or limitations of percutaneous procedures. Herein we report a case of a patient presenting with type B aortic dissection complicated by visceral malperfusion and AAA which was successfully treated simultaneously by open AAA repair and surgical fenestration. We focus on the mechanism of malperfusion and on the role of surgical fenestration.