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CEUS demonstrated to be as accurate as CTA in endoleak detection and abdominal aortic aneurysm diameter measurements during EVAR follow-up, without carrying the risks of radiation exposure or nephrotoxicity. Even if it cannot be proposed as the sole imaging modality during follow-up, our analysis suggests that it should have a major role.

CEUS is as accurate as CTA in endoleak detection, abdominal aortic aneurysm diameter measurement, and the evaluation of target vessels during surveillance of fenestrated stent-grafts. Although it cannot yet be proposed as the only imaging modality during follow-up, CEUS could be usefully employed with the self-evident advantage of reducing lifetime exposure to ionizing radiation.

Indirect DAP values measured by the C-arm are accurate to evaluate radiation exposure. Compared to the literature, our values for standard procedures are significantly decreased by the usage of low dose and pulse mode. DAP for fenestrated and branched procedures was comparable to published DAP values with standard procedures using a regular fluoroscopic mode.

Endovascular treatment with fenestrated and branched endografts should be considered in challenging renal artery anatomies in patients unfit for open repair.

The design of 3D complex structures enables new correlation studies between the engineering parameters and the biological activity. Moreover, additive manufacturing technology could revolutionise the personalised medical pre-operative management due to its possibility to interplay with computer tomography. Here we present a method based on rapid freeze prototyping (RFP) 3D printer, reconstruction cutting, nano dry formulation, fast freeze gelation, disinfection and partial processes for the 5D digital models functionalisation. We elaborated the high-resolution computer tomography scan derived from a complex human peripheral artery and we reconstructed the 3D model of the vessel in order to obtain and verify the additive manufacturing processes. Then, based on the drug-eluting balloon selected for the percutaneous intervention, we reconstructed the biocompatible eluting-freeform coating containing 40 nm fluorescent nanoparticles (NPs) by means of RFP printer and we tested the in-vivo feasibility. We introduced the NPs-loaded 5D device in a rat's vena cava. The coating dissolved in a few minutes releasing NPs which were rapidly absorbed in vascular smooth muscle cell (VSMC) and human umbilical vein endothelial cell (HUVEC) in-vitro. We developed 5D highresolution self-dissolving devices incorporating NPs with the perspective to apply this method to the personalised medicine.Chronic lower extremity peripheral arterial disease (PAD) is a manifestation of systemic atherosclerosis, and one of the main causes in loss of walking ability. Two treatments for lower extremity PAD are currently available: surgical (primarily bypass surgery) and endovascular treatment (EVT) mainly through balloon angioplasty. In fact, due to its clear advantages at least in the short-term, EVT represents -at present -the most common treatment for PAD 1 . Drug-Coated Balloons are made up of a semi-compliant or non-compliant balloon catheter covered with an anti-proliferative agent (typically paclitaxel), and an excipient (e.g. urea) to facilitate drug transfer into the vessel wall after balloon inflation 2 . The BASIL (Bypass Versus Angioplasty for Severe Ischemia of the Leg) trial is the only multicentre, randomised and controlled trial (RCT) which compared these two treatments 3 . One of the major limitations of this RCT is that current endovascular technologies have not been included 4 . Important advances developed in endovascular technologies address a great variety of anatomic challenges, while current and future efforts are directed towards improving long-term patency rates.The 3D printing techniques demonstrate the high potentiality of interactive processes applied to medicine and associated toxicity/vitality studies 5,6 . Materials selected for bio-printed scaffolds are predominantly based on both naturally derived polymers (including gelatine, collagen, alginate, chitosan and hyaluronic acid) or synthetic molecules (polyethylene glycol) 7-9 , allowing precise control 10 of chemical and physical properties 11 .

Degenerative aneurysms of the SFA display peculiar characteristics (in terms of clinical onset, diagnostic timing, and clinical behavior) so that they differ from other peripheral aneurysms. In fact, they often grow to reach a considerable diameter before medical attention is sought, presenting with rupture or ischemia at diagnosis. SFA aneurysms preferentially affect elderly men and are often associated with aneurysms elsewhere. However, despite their rarity, the treatment is usually feasible, and long-term outcomes are good.

WHAT THIS PAPER ADDSLate open conversions for endovascular aneurysm repair complications have increased in number over the last 20 years. They are technically challenging operations, with high post-operative mortality and morbidity rates, especially for infection and urgent operations. Morbidity rates are lower when the endograft is clamped infrarenally.Objective: The aim was to report indications, technical aspects, and outcomes of a multicentre experience of late open conversions (LOCs) after endovascular abdominal aneurysm repair (EVAR), in order to identify risk factors which may influence early morbidity and mortality rates, and long term survival. Methods: Ten vascular centres retrospectively reviewed all patients requiring LOC (!30 days from initial EVAR, undergoing total or partial endograft explantation) from 1996 to 2017. Baseline characteristics, endograft data, indications, procedural details, post-operative outcomes, and follow up data were reviewed and analysed. Results: Included patients totalled 232 (90.1% males, mean age 74.3 AE 7.9 years). The number of LOC per year significantly increased during the study period, reaching 22 in 2017 (correlation r ¼ 0.867, p < .0001). Reasons for LOC were 80.2% endoleak (186/232), 15.5% endograft infection (36/232), and 9.9% endograft thrombosis (23/232). Sixty-nine patients (29.7%) were operated on urgently; rupture was present in 18.5% (43/232). Eighty-nine patients (38.4%) underwent endovascular re-interventions prior to LOC. The proximal aortic cross clamp site was infrarenal in 40.5% (94/232), suprarenal in 25.4% (59/232), supracoeliac in 32.8% (76/232), and thoracic in 1.3% (3/232). Endograft explantation was total in 164/232 patients (70.7%), and partial in the remaining 68/232 (29.3%). The overall 30 day mortality was 11.2% (26/232). Early mortality was significantly higher for patients operated on urgently (26.1% vs. 4.9%, p < .001). Suprarenal clamping (odds ratio (OR) 2.34, 95% CI 1.12e4.88) and pre-existing renal insufficiency (OR 2.11, 95% CI 1.03e4.31) were independent risk factors for post-operative renal failure on multivariable analysis. Median follow up was 24.1 months (IQR 4.4e60.6). The estimated overall one and five year survival rates were 79.7% and 58.6%, respectively. Survival estimates were significantly lower for patients with endograft infection (83.8% vs. 59% at one year, 65.2% vs. 28.9% at five years; log rank p ¼ .005), as well as for urgent patients (87.2% vs. 62.1% at one year, 65.1% vs. 43.7% at five years; log rank p < .0001). Conclusion:The annual number of LOC increased over time. LOCs performed urgently or for endograft infection are associated with poor survival. Infrarenal aortic clamping has lower post-operative complication rates.