Abdominal aortic aneurysm volume and relative intraluminal thrombus volume might be auxiliary predictors of rupture-an observational cross-sectional study

Objectives

The study aimed to identify differences and compare anatomical and biomechanical features between elective and ruptured abdominal aortic aneurysms (AAAs).

Methods

Data (clinical, anatomical, and biomechanical) of 98 patients with AAA, 75 (76.53%) asymptomatic (Group aAAA) and 23 (23.46%) ruptured AAA (Group rAAA), were prospectively collected and analyzed. Anatomical, morphological, and biomechanical imaging markers like peak wall stress (PWS) and rupture risk equivalent diameter (RRED), comorbid conditions, and demographics were compared between the groups. Biomechanical features were assessed by analysis of Digital Imaging and Communication in Medicine images by A4clinics (Vascops), and anatomical features were assessed by 3Surgery (Trimensio). Binary and multiple logistic regression analysis were used and adjusted for confounders. Accuracy was assessed using receiving operative characteristic (ROC) curve analysis.

Results

In a multivariable model, including gender and age as confounder variables, maximal aneurysm diameter [MAD, odds ratio (OR) = 1.063], relative intraluminal thrombus (rILT, OR = 1.039), and total aneurysm volume (TAV, OR = 1.006) continued to be significant predictors of AAA rupture with PWS (OR = 1.010) and RRED (OR = 1.031). Area under the ROC curve values and correct classification (cc) for the same parameters and the model that combines MAD, TAV, and rILT were measured: MAD (0.790, cc = 75%), PWS (0.713, cc = 73%), RRED (0.717, cc = 55%), TAV (0.756, cc = 79%), rILT (0.656, cc = 60%), and MAD + TAV + rILT (0.797, cc = 82%).

Conclusion

Based on our results, in addition to MAD, other important predictors of rupture that might be used during aneurysm surveillance are TAV and rILT. Biomechanical parameters (PWS, RRED) as valuable predictors should be assessed in prospective clinical trials. Similar studies on AAA smaller than 55 mm in diameter, even difficult to organize, would be of even greater clinical value.

Hybrid repair of aortic arch with zone zero endografting-Case series with review of the literature

INTRODUCTION

We present single-institution results of types I and II hybrid procedures for aortic arch disease with 30-day and long-term results and review of the literature.

MATERIALS AND METHODS

This is a retrospective study of all patients that underwent zone 0 endografting and open bypass from ascending aorta to the arch vessels at our institution between January 2013 and 2020. The following data for the systematic review were extracted from eligible studies: 30-day/in-hospital mortality, stroke rate, spinal cord ischemia (SCI) rate, renal failure requiring dialysis, development of retrograde dissection, early (<30 days) types I and III endoleak, follow-up length, late (>30 days) endoleak, and late (>30 days) mortality.

RESULTS

Twelve patients underwent hybrid aortic arch treatment in our institution. The most common aortic arch pathology was degenerative aortic aneurysm. The rate of retrograde dissection and SCI was 8.33%. Regarding the literature data, a total of 768 patients undergoing types I and II hybrid aortic arch debranching procedure. The pooled rate of 30-day/in-hospital mortality was 10.96% (95% confidence interval [CI], 8.21-14.06), SCI pooled rate was 2.91% (95% CI, 1.76%-4.33%), and retrograde dissection pooled rate was 3.22% (95% CI, 1.99-4.72).

CONCLUSION

Hybrid arch techniques provide safe alternative to open repair with acceptable short- and midterm results.

Open Surgical Treatment of Acute Spontaneous Isolated Abdominal Aortic Dissection

BACKGROUND

The aim of this paper is to report our single-center experience in the open surgical treatment of acute spontaneous infrarenal isolated abdominal aortic dissection (siIAAD).

METHODS

This was a single center retrospective study. Between January 2015 and 2020 ten patients were treated due to acute siIAAD with open surgery. There were no patients treated for chronic siIAAD in this time period. Patients who had concomitant thoracic aortic involvement were excluded from this report.

RESULTS

The group consisted of 7 male and 3 female patients. History of hypertension was present in nine patients and six were active smokers. The abdominal/back pain was described in 9 patients, two had acute limb ischemia and three had aortic rupture. Median dissection length was 91 mm (65.7 - 106), median distance from the lowest renal artery was 30 mm (20.7 - 49.3) and median abdominal aortic diameter was 58.5 mm (32.5 - 66.2). Supracoeliac clamp was used in three cases with a ruptured aorta and suprarenal in two patients. The mean duration of proximal clamping time was 24.3 ± 7.49 min. One patient died of postoperative acute myocardial infarction, one suffered nonfatal pulmonary embolism and one had deep venous thrombosis. No aortic-related deaths and/or reinterventions occurred during the median follow-up of 32 months.

CONCLUSIONS

Acute siIAAD is a rare event which affects mostly male smokers with hypertension. Open surgery is a technically demanding procedure with acceptable complication rates and should be performed in specialized high-volume centers for the treatment of aortic disease. Future efforts to establish a multicenter registry to evaluate the prevalence of the disease and treatment options could provide better and more comprehensive guidelines for the treatment of acute siIAAAD.

Impact of Bypass Flow Assessment on Long-Term Outcomes in Patients with Chronic Limb-Threatening Ischemia

BACKGROUND

Transit time flow meter (TTFM) allows quick and accurate intraoperative graft assessment. The main study goal is to evaluate the influence of graft flow measurements on long-term clinical outcomes in patients with chronic limb-threatening ischemia (CLTI) undergoing bellow the knee (BTK) vein bypass surgery.

METHODS

Between January 1st, 1999 and January 1st, 2006, 976 CLTI consecutive patients underwent lower extremity bypass surgery. When applying the exclusion criteria, 249 patients were included in the final analysis. Control measurements were performed at the end of the procedure. Patients were divided according to the mean (more/less than 100 ml/min) and diastolic graft flow (more/less than 40 ml/min) values in four groups. The primary endpoints were a major adverse limb event (male) and primary graft patency.

RESULTS

After the median follow-up of 68 months, a group with the mean graft flow below 100 ml/min and the diastolic graft flow below 40 ml/min had the highest rates of male (χ² = 36.60, DF = 1, P < 0.01, log-rank test) and the worst primary graft patency (χ² = 53.05, DF = 1, P < 0.01, log-rank test).

CONCLUSION

In patients with CLTI undergoing BTK vein bypass surgery, TTFM parameters, especially combined impact of mean graft flow less than 100 ml/min and diastolic graft flow less than 40 ml/min, were associated with an increased risk of poor long-term male and primary graft patency.

A deep learning oriented method for automated 3D reconstruction of carotid arterial trees from MR imaging

The scope of this paper is to present a new carotid vessel segmentation algorithm implementing the U-net based convolutional neural network architecture. With carotid atherosclerosis being the major cause of stroke in Europe, new methods that can provide more accurate image segmentation of the carotid arterial tree and plaque tissue can help improve early diagnosis, prevention and treatment of carotid disease. Herein, we present a novel methodology combining the U-net model and morphological active contours in an iterative framework that accurately segments the carotid lumen and outer wall. The method automatically produces a 3D meshed model of the carotid bifurcation and smaller branches, using multispectral MR image series obtained from two clinical centres of the TAXINOMISIS study. As indicated by a validation study, the algorithm succeeds high accuracy (99.1% for lumen area and 92.6% for the perimeter) for lumen segmentation. The proposed algorithm will be used in the TAXINOMISIS study to obtain more accurate 3D vessel models for improved computational fluid dynamics simulations and the development of models of atherosclerotic plaque progression.